case study for problems

173 Case Studies: Real Stories Of People Overcoming Struggles of Mental Health

At Tracking Happiness, we’re dedicated to helping others around the world overcome struggles of mental health.

In 2022, we published a survey of 5,521 respondents and found:

• 88% of our respondents experienced mental health issues in the past year.
• 25% of people don’t feel comfortable sharing their struggles with anyone, not even their closest friends.

In order to break the stigma that surrounds mental health struggles, we’re looking to share your stories.

Overcoming struggles

They say that everyone you meet is engaged in a great struggle. No matter how well someone manages to hide it, there’s always something to overcome, a struggle to deal with, an obstacle to climb.

And when someone is engaged in a struggle, that person is looking for others to join him. Because we, as human beings, don’t thrive when we feel alone in facing a struggle.

Let’s throw rocks together

Overcoming your struggles is like defeating an angry giant. You try to throw rocks at it, but how much damage is one little rock gonna do?

Tracking Happiness can become your partner in facing this giant. We are on a mission to share all your stories of overcoming mental health struggles. By doing so, we want to help inspire you to overcome the things that you’re struggling with, while also breaking the stigma of mental health.

Which explains the phrase: “Let’s throw rocks together”.

Let’s throw rocks together, and become better at overcoming our struggles collectively. If you’re interested in becoming a part of this and sharing your story, click this link!

Case studies

October 15, 2024

How I Stopped Obsessively Controlling My Body and Accepted My Values Instead

“I became interested in health and wellness and started to learn about healthy foods, nervous system exercises, energy, etc. And the same pattern of control started again disguised as health and wellness. Because of the way I was treated growing up and as a young adult, I felt there was something deeply wrong with me- like I was not loveable as I was. I needed to control my body to feel like I was enough, to make myself loveable so that I could be happy.”

Struggled with: Eating disorder Negative body image

Helped by: Self-acceptance Self-improvement

October 8, 2024

My Struggle with Depression While Finding Strength Through Mental Health Advocacy

“While I have a great support system, I did not feel like they truly understood what it felt like to be me. I really wished I could talk to people unfiltered about how sad I was and how I did not see a light at the end of the tunnel. I was still on my medicine and in therapy, but I had quit my fancy finance job, ended my relationship and urgently needed to work on myself.”

Struggled with: Depression

Helped by: Medication Self-Care

October 1, 2024

From Burnout to Balance: How I Found Happiness After Career Overload

“I experienced burnout. It was so severe that I could barely get out of bed or feed myself anything more than a bag of chips. I had also ground my teeth so badly that I was experiencing shooting pain in my jaw. When I saw the dentist, she told me that the damage to my teeth was permanent. To this day I often have pain when eating or drinking very hot or cold items.”

Struggled with: Burnout

Helped by: Self-Care Self-improvement

September 24, 2024

My Journey From Constant Self-Doubt and Anxiety to Becoming a Bestselling Author

“I’m honestly not sure if others knew or noticed because I kept it inside. People definitely noticed (and commented) that I was quiet or shy or didn’t speak up much – which didn’t help! But nobody knew what was really going on in my head and I didn’t talk about it, but I did write about it and writing has been my safe space ever since!”

Struggled with: Anxiety Self-doubt

Helped by: Self-improvement

September 17, 2024

My Fight Against Anxiety, PTSD, and Depression After Being Laid Off

“Neglect, abuse, and the profound impact of my mother’s involvement in the witness protection program marked my childhood. These experiences left deep emotional scars that have taken years to understand and manage. These challenges have ebbed and flowed over time. Yet, they’ve always been a constant presence, influencing how I see the world and interact with it.”

Struggled with: ADHD Anxiety Depression PTSD

Helped by: Reinventing yourself Self-improvement

September 10, 2024

My Journey of Overcoming Postpartum Depression and an Eating Disorder

“I was concerned about how my struggles might affect others’ perceptions of me and my competence as a mother and professional. This led me to mask my feelings and put on a brave face, even when I was feeling my lowest. Seeking help was a pivotal moment, but until then, I often felt like I had to navigate these challenges alone, despite the support and understanding that others might have been willing to offer.”

Struggled with: Eating disorder Postpartum depression

Helped by: Social support Therapy

September 3, 2024

Exercise, Therapy and Religion Helped Me Climb Out Of Alcoholism and Unhappiness

“The moment I felt something change for the better was when I was sitting at a bar sipping on a beer, and I called my father. I told him I truly didn’t want to drink anymore and really wanted to get sober. He sighed and said, “We tried to help you. Now it’s up to you just to stop drinking.” I asked him how that was going to be possible considering all of my options ran out. He screamed into the phone, “JUST STOP” and hung up.”

Struggled with: Addiction Assault

Helped by: Exercise God Therapy

August 27, 2024

A Bipolar Diagnosis Finally Helped Me understand How To Be Happy In Life

“After I was diagnosed, it took another 3 years before I found what balance of medication and therapy worked for me. I had to try to keep my grades up and maintain my friendships while battling severe mood swings and extreme tiredness, in addition to all of the regular drama that comes along with adolescence.”

Struggled with: Bipolar Disorder

Helped by: Medication Therapy

August 20, 2024

Overcoming Reactive Attachment Disorder and Depression with Self-Care and Therapy

“Despite experiencing severe depressive symptoms, including suicidal ideation, I made a concerted effort to appear upbeat and engaged in social settings. This involved forcing myself to smile, laugh, and participate in conversations as if everything was fine, even when I was internally battling intense emotional pain that I felt I was not safe to reveal.”

Struggled with: Childhood trauma Depression People-pleasing Reactive Attachment Disorder

Helped by: Self-Care Therapy

August 13, 2024

Finding Happiness At Sea As A Yacht Captain After Overcoming Depression and Anxiety

“If a situation is making you unhappy – a marriage, a job, a family member – anything – change the situation. You can leave, you can stop speaking to someone (yes, even a parent or another family member), and you can do so free of guilt because you are in charge of your own happiness, and life is too short to choose anything different for yourself.”

Struggled with: Anxiety Depression Suicidal

We use essential cookies to make Venngage work. By clicking “Accept All Cookies”, you agree to the storing of cookies on your device to enhance site navigation, analyze site usage, and assist in our marketing efforts.

Manage Cookies

Cookies and similar technologies collect certain information about how you’re using our website. Some of them are essential, and without them you wouldn’t be able to use Venngage. But others are optional, and you get to choose whether we use them or not.

Strictly Necessary Cookies

These cookies are always on, as they’re essential for making Venngage work, and making it safe. Without these cookies, services you’ve asked for can’t be provided.

Show cookie providers

• Google Login

Functionality Cookies

These cookies help us provide enhanced functionality and personalisation, and remember your settings. They may be set by us or by third party providers.

Performance Cookies

These cookies help us analyze how many people are using Venngage, where they come from and how they're using it. If you opt out of these cookies, we can’t get feedback to make Venngage better for you and all our users.

• Google Analytics

Targeting Cookies

These cookies are set by our advertising partners to track your activity and show you relevant Venngage ads on other sites as you browse the internet.

• Google Tag Manager
• Infographics
• Daily Infographics
• Popular Templates
• Accessibility
• Graphic Design
• Graphs and Charts
• Data Visualization
• Human Resources
• Beginner Guides

Blog Business How to Present a Case Study like a Pro (With Examples)

How to Present a Case Study like a Pro (With Examples)

Written by: Danesh Ramuthi Sep 07, 2023

Okay, let’s get real: case studies can be kinda snooze-worthy. But guess what? They don’t have to be!

In this article, I will cover every element that transforms a mere report into a compelling case study, from selecting the right metrics to using persuasive narrative techniques.

And if you’re feeling a little lost, don’t worry! There are cool tools like Venngage’s Case Study Creator to help you whip up something awesome, even if you’re short on time. Plus, the pre-designed case study templates are like instant polish because let’s be honest, everyone loves a shortcut.

Click to jump ahead: 

What is a case study presentation?

What is the purpose of presenting a case study, how to structure a case study presentation, how long should a case study presentation be, 5 case study presentation examples with templates, 6 tips for delivering an effective case study presentation, 5 common mistakes to avoid in a case study presentation, how to present a case study faqs.

A case study presentation involves a comprehensive examination of a specific subject, which could range from an individual, group, location, event, organization or phenomenon.

They’re like puzzles you get to solve with the audience, all while making you think outside the box.

Unlike a basic report or whitepaper, the purpose of a case study presentation is to stimulate critical thinking among the viewers. 

The primary objective of a case study is to provide an extensive and profound comprehension of the chosen topic. You don’t just throw numbers at your audience. You use examples and real-life cases to make you think and see things from different angles.

The primary purpose of presenting a case study is to offer a comprehensive, evidence-based argument that informs, persuades and engages your audience.

Here’s the juicy part: presenting that case study can be your secret weapon. Whether you’re pitching a groundbreaking idea to a room full of suits or trying to impress your professor with your A-game, a well-crafted case study can be the magic dust that sprinkles brilliance over your words.

Think of it like digging into a puzzle you can’t quite crack . A case study lets you explore every piece, turn it over and see how it fits together. This close-up look helps you understand the whole picture, not just a blurry snapshot.

It’s also your chance to showcase how you analyze things, step by step, until you reach a conclusion. It’s all about being open and honest about how you got there.

Besides, presenting a case study gives you an opportunity to connect data and real-world scenarios in a compelling narrative. It helps to make your argument more relatable and accessible, increasing its impact on your audience.

One of the contexts where case studies can be very helpful is during the job interview. In some job interviews, you as candidates may be asked to present a case study as part of the selection process.

Having a case study presentation prepared allows the candidate to demonstrate their ability to understand complex issues, formulate strategies and communicate their ideas effectively.

The way you present a case study can make all the difference in how it’s received. A well-structured presentation not only holds the attention of your audience but also ensures that your key points are communicated clearly and effectively.

In this section, let’s go through the key steps that’ll help you structure your case study presentation for maximum impact.

Let’s get into it. 

Open with an introductory overview 

Start by introducing the subject of your case study and its relevance. Explain why this case study is important and who would benefit from the insights gained. This is your opportunity to grab your audience’s attention.

Explain the problem in question

Dive into the problem or challenge that the case study focuses on. Provide enough background information for the audience to understand the issue. If possible, quantify the problem using data or metrics to show the magnitude or severity.

Detail the solutions to solve the problem

After outlining the problem, describe the steps taken to find a solution. This could include the methodology, any experiments or tests performed and the options that were considered. Make sure to elaborate on why the final solution was chosen over the others.

Key stakeholders Involved

Talk about the individuals, groups or organizations that were directly impacted by or involved in the problem and its solution. 

Stakeholders may experience a range of outcomes—some may benefit, while others could face setbacks.

For example, in a business transformation case study, employees could face job relocations or changes in work culture, while shareholders might be looking at potential gains or losses.

Discuss the key results & outcomes

Discuss the results of implementing the solution. Use data and metrics to back up your statements. Did the solution meet its objectives? What impact did it have on the stakeholders? Be honest about any setbacks or areas for improvement as well.

Include visuals to support your analysis

Visual aids can be incredibly effective in helping your audience grasp complex issues. Utilize charts, graphs, images or video clips to supplement your points. Make sure to explain each visual and how it contributes to your overall argument.

Pie charts illustrate the proportion of different components within a whole, useful for visualizing market share, budget allocation or user demographics.

This is particularly useful especially if you’re displaying survey results in your case study presentation.

Stacked charts on the other hand are perfect for visualizing composition and trends. This is great for analyzing things like customer demographics, product breakdowns or budget allocation in your case study.

Consider this example of a stacked bar chart template. It provides a straightforward summary of the top-selling cake flavors across various locations, offering a quick and comprehensive view of the data.

Not the chart you’re looking for? Browse Venngage’s gallery of chart templates to find the perfect one that’ll captivate your audience and level up your data storytelling.

Recommendations and next steps

Wrap up by providing recommendations based on the case study findings. Outline the next steps that stakeholders should take to either expand on the success of the project or address any remaining challenges.

Acknowledgments and references

Thank the people who contributed to the case study and helped in the problem-solving process. Cite any external resources, reports or data sets that contributed to your analysis.

Feedback & Q&A session

Open the floor for questions and feedback from your audience. This allows for further discussion and can provide additional insights that may not have been considered previously.

Closing remarks

Conclude the presentation by summarizing the key points and emphasizing the takeaways. Thank your audience for their time and participation and express your willingness to engage in further discussions or collaborations on the subject.

Well, the length of a case study presentation can vary depending on the complexity of the topic and the needs of your audience. However, a typical business or academic presentation often lasts between 15 to 30 minutes. 

This time frame usually allows for a thorough explanation of the case while maintaining audience engagement. However, always consider leaving a few minutes at the end for a Q&A session to address any questions or clarify points made during the presentation.

When it comes to presenting a compelling case study, having a well-structured template can be a game-changer. 

It helps you organize your thoughts, data and findings in a coherent and visually pleasing manner. 

Not all case studies are created equal and different scenarios require distinct approaches for maximum impact. 

To save you time and effort, I have curated a list of 5 versatile case study presentation templates, each designed for specific needs and audiences. 

Here are some best case study presentation examples that showcase effective strategies for engaging your audience and conveying complex information clearly.

1 . Lab report case study template

Ever feel like your research gets lost in a world of endless numbers and jargon? Lab case studies are your way out!

Think of it as building a bridge between your cool experiment and everyone else. It’s more than just reporting results – it’s explaining the “why” and “how” in a way that grabs attention and makes sense.

This lap report template acts as a blueprint for your report, guiding you through each essential section (introduction, methods, results, etc.) in a logical order.

Want to present your research like a pro? Browse our research presentation template gallery for creative inspiration!

2. Product case study template

It’s time you ditch those boring slideshows and bullet points because I’ve got a better way to win over clients: product case study templates.

Instead of just listing features and benefits, you get to create a clear and concise story that shows potential clients exactly what your product can do for them. It’s like painting a picture they can easily visualize, helping them understand the value your product brings to the table.

Grab the template below, fill in the details, and watch as your product’s impact comes to life!

3. Content marketing case study template

In digital marketing, showcasing your accomplishments is as vital as achieving them. 

A well-crafted case study not only acts as a testament to your successes but can also serve as an instructional tool for others. 

With this coral content marketing case study template—a perfect blend of vibrant design and structured documentation, you can narrate your marketing triumphs effectively.

4. Case study psychology template

Understanding how people tick is one of psychology’s biggest quests and case studies are like magnifying glasses for the mind. They offer in-depth looks at real-life behaviors, emotions and thought processes, revealing fascinating insights into what makes us human.

Writing a top-notch case study, though, can be a challenge. It requires careful organization, clear presentation and meticulous attention to detail. That’s where a good case study psychology template comes in handy.

Think of it as a helpful guide, taking care of formatting and structure while you focus on the juicy content. No more wrestling with layouts or margins – just pour your research magic into crafting a compelling narrative.

5. Lead generation case study template

Lead generation can be a real head-scratcher. But here’s a little help: a lead generation case study.

Think of it like a friendly handshake and a confident resume all rolled into one. It’s your chance to showcase your expertise, share real-world successes and offer valuable insights. Potential clients get to see your track record, understand your approach and decide if you’re the right fit.

No need to start from scratch, though. This lead generation case study template guides you step-by-step through crafting a clear, compelling narrative that highlights your wins and offers actionable tips for others. Fill in the gaps with your specific data and strategies, and voilà! You’ve got a powerful tool to attract new customers.

Related: 15+ Professional Case Study Examples [Design Tips + Templates]

So, you’ve spent hours crafting the perfect case study and are now tasked with presenting it. Crafting the case study is only half the battle; delivering it effectively is equally important. 

Whether you’re facing a room of executives, academics or potential clients, how you present your findings can make a significant difference in how your work is received. 

Forget boring reports and snooze-inducing presentations! Let’s make your case study sing. Here are some key pointers to turn information into an engaging and persuasive performance:

• Know your audience : Tailor your presentation to the knowledge level and interests of your audience. Remember to use language and examples that resonate with them.
• Rehearse : Rehearsing your case study presentation is the key to a smooth delivery and for ensuring that you stay within the allotted time. Practice helps you fine-tune your pacing, hone your speaking skills with good word pronunciations and become comfortable with the material, leading to a more confident, conversational and effective presentation.
• Start strong : Open with a compelling introduction that grabs your audience’s attention. You might want to use an interesting statistic, a provocative question or a brief story that sets the stage for your case study.
• Be clear and concise : Avoid jargon and overly complex sentences. Get to the point quickly and stay focused on your objectives.
• Use visual aids : Incorporate slides with graphics, charts or videos to supplement your verbal presentation. Make sure they are easy to read and understand.
• Tell a story : Use storytelling techniques to make the case study more engaging. A well-told narrative can help you make complex data more relatable and easier to digest.

Ditching the dry reports and slide decks? Venngage’s case study templates let you wow customers with your solutions and gain insights to improve your business plan. Pre-built templates, visual magic and customer captivation – all just a click away. Go tell your story and watch them say “wow!”

Nailed your case study, but want to make your presentation even stronger? Avoid these common mistakes to ensure your audience gets the most out of it:

Overloading with information

A case study is not an encyclopedia. Overloading your presentation with excessive data, text or jargon can make it cumbersome and difficult for the audience to digest the key points. Stick to what’s essential and impactful. Need help making your data clear and impactful? Our data presentation templates can help! Find clear and engaging visuals to showcase your findings.

Lack of structure

Jumping haphazardly between points or topics can confuse your audience. A well-structured presentation, with a logical flow from introduction to conclusion, is crucial for effective communication.

Ignoring the audience

Different audiences have different needs and levels of understanding. Failing to adapt your presentation to your audience can result in a disconnect and a less impactful presentation.

Poor visual elements

While content is king, poor design or lack of visual elements can make your case study dull or hard to follow. Make sure you use high-quality images, graphs and other visual aids to support your narrative.

Not focusing on results

A case study aims to showcase a problem and its solution, but what most people care about are the results. Failing to highlight or adequately explain the outcomes can make your presentation fall flat.

How to start a case study presentation?

Starting a case study presentation effectively involves a few key steps:

• Grab attention : Open with a hook—an intriguing statistic, a provocative question or a compelling visual—to engage your audience from the get-go.
• Set the stage : Briefly introduce the subject, context and relevance of the case study to give your audience an idea of what to expect.
• Outline objectives : Clearly state what the case study aims to achieve. Are you solving a problem, proving a point or showcasing a success?
• Agenda : Give a quick outline of the key sections or topics you’ll cover to help the audience follow along.
• Set expectations : Let your audience know what you want them to take away from the presentation, whether it’s knowledge, inspiration or a call to action.

How to present a case study on PowerPoint and on Google Slides?

Presenting a case study on PowerPoint and Google Slides involves a structured approach for clarity and impact using presentation slides :

• Title slide : Start with a title slide that includes the name of the case study, your name and any relevant institutional affiliations.
• Introduction : Follow with a slide that outlines the problem or situation your case study addresses. Include a hook to engage the audience.
• Objectives : Clearly state the goals of the case study in a dedicated slide.
• Findings : Use charts, graphs and bullet points to present your findings succinctly.
• Analysis : Discuss what the findings mean, drawing on supporting data or secondary research as necessary.
• Conclusion : Summarize key takeaways and results.
• Q&A : End with a slide inviting questions from the audience.

What’s the role of analysis in a case study presentation?

The role of analysis in a case study presentation is to interpret the data and findings, providing context and meaning to them. 

It helps your audience understand the implications of the case study, connects the dots between the problem and the solution and may offer recommendations for future action.

Is it important to include real data and results in the presentation?

Yes, including real data and results in a case study presentation is crucial to show experience,  credibility and impact. Authentic data lends weight to your findings and conclusions, enabling the audience to trust your analysis and take your recommendations more seriously

How do I conclude a case study presentation effectively?

To conclude a case study presentation effectively, summarize the key findings, insights and recommendations in a clear and concise manner. 

End with a strong call-to-action or a thought-provoking question to leave a lasting impression on your audience.

What’s the best way to showcase data in a case study presentation ?

The best way to showcase data in a case study presentation is through visual aids like charts, graphs and infographics which make complex information easily digestible, engaging and creative. 

Don’t just report results, visualize them! This template for example lets you transform your social media case study into a captivating infographic that sparks conversation.

Choose the type of visual that best represents the data you’re showing; for example, use bar charts for comparisons or pie charts for parts of a whole. 

Ensure that the visuals are high-quality and clearly labeled, so the audience can quickly grasp the key points. 

Keep the design consistent and simple, avoiding clutter or overly complex visuals that could distract from the message.

Choose a template that perfectly suits your case study where you can utilize different visual aids for maximum impact. 

Need more inspiration on how to turn numbers into impact with the help of infographics? Our ready-to-use infographic templates take the guesswork out of creating visual impact for your case studies with just a few clicks.

Related: 10+ Case Study Infographic Templates That Convert

Congrats on mastering the art of compelling case study presentations! This guide has equipped you with all the essentials, from structure and nuances to avoiding common pitfalls. You’re ready to impress any audience, whether in the boardroom, the classroom or beyond.

And remember, you’re not alone in this journey. Venngage’s Case Study Creator is your trusty companion, ready to elevate your presentations from ordinary to extraordinary. So, let your confidence shine, leverage your newly acquired skills and prepare to deliver presentations that truly resonate.

Go forth and make a lasting impact!

Discover popular designs

Infographic maker

Brochure maker

White paper online

Newsletter creator

Flyer maker

Timeline maker

Letterhead maker

Mind map maker

Ebook maker

Due to recent expansions in US sanctions against Russia and Belarus as well as existing country-level sanctions in Iran, North Korea, Syria, Cuba, and the Crimea region (each a “sanctioned country”), Zapier will no longer be able to provide services in any sanctioned country starting September 12, 2024. These sanctions prohibit US companies from offering certain IT and enterprise software services in a sanctioned region.

Starting September 12, 2024, Zapier customers will no longer be able to access Zapier services from a sanctioned country. We understand this may be inconvenient and appreciate your understanding as we navigate these regulatory requirements.

• Bipolar Disorder
• Therapy Center
• When To See a Therapist
• Types of Therapy
• Best Online Therapy
• Best Couples Therapy
• Managing Stress
• Sleep and Dreaming
• Understanding Emotions
• Self-Improvement
• Healthy Relationships
• Student Resources
• Personality Types
• Guided Meditations
• Verywell Mind Insights
• 2024 Verywell Mind 25
• Mental Health in the Classroom
• Editorial Process
• Meet Our Review Board
• Crisis Support

What Is a Case Study?

Weighing the pros and cons of this method of research

Kendra Cherry, MS, is a psychosocial rehabilitation specialist, psychology educator, and author of the "Everything Psychology Book."

Cara Lustik is a fact-checker and copywriter.

Verywell / Colleen Tighe

• Pros and Cons

What Types of Case Studies Are Out There?

Where do you find data for a case study, how do i write a psychology case study.

A case study is an in-depth study of one person, group, or event. In a case study, nearly every aspect of the subject's life and history is analyzed to seek patterns and causes of behavior. Case studies can be used in many different fields, including psychology, medicine, education, anthropology, political science, and social work.

The point of a case study is to learn as much as possible about an individual or group so that the information can be generalized to many others. Unfortunately, case studies tend to be highly subjective, and it is sometimes difficult to generalize results to a larger population.

While case studies focus on a single individual or group, they follow a format similar to other types of psychology writing. If you are writing a case study, we got you—here are some rules of APA format to reference.  

At a Glance

A case study, or an in-depth study of a person, group, or event, can be a useful research tool when used wisely. In many cases, case studies are best used in situations where it would be difficult or impossible for you to conduct an experiment. They are helpful for looking at unique situations and allow researchers to gather a lot of˜ information about a specific individual or group of people. However, it's important to be cautious of any bias we draw from them as they are highly subjective.

What Are the Benefits and Limitations of Case Studies?

A case study can have its strengths and weaknesses. Researchers must consider these pros and cons before deciding if this type of study is appropriate for their needs.

One of the greatest advantages of a case study is that it allows researchers to investigate things that are often difficult or impossible to replicate in a lab. Some other benefits of a case study:

• Allows researchers to capture information on the 'how,' 'what,' and 'why,' of something that's implemented
• Gives researchers the chance to collect information on why one strategy might be chosen over another
• Permits researchers to develop hypotheses that can be explored in experimental research

On the other hand, a case study can have some drawbacks:

• It cannot necessarily be generalized to the larger population
• Cannot demonstrate cause and effect
• It may not be scientifically rigorous
• It can lead to bias

Researchers may choose to perform a case study if they want to explore a unique or recently discovered phenomenon. Through their insights, researchers develop additional ideas and study questions that might be explored in future studies.

It's important to remember that the insights from case studies cannot be used to determine cause-and-effect relationships between variables. However, case studies may be used to develop hypotheses that can then be addressed in experimental research.

Case Study Examples

There have been a number of notable case studies in the history of psychology. Much of  Freud's work and theories were developed through individual case studies. Some great examples of case studies in psychology include:

• Anna O : Anna O. was a pseudonym of a woman named Bertha Pappenheim, a patient of a physician named Josef Breuer. While she was never a patient of Freud's, Freud and Breuer discussed her case extensively. The woman was experiencing symptoms of a condition that was then known as hysteria and found that talking about her problems helped relieve her symptoms. Her case played an important part in the development of talk therapy as an approach to mental health treatment.
• Phineas Gage : Phineas Gage was a railroad employee who experienced a terrible accident in which an explosion sent a metal rod through his skull, damaging important portions of his brain. Gage recovered from his accident but was left with serious changes in both personality and behavior.
• Genie : Genie was a young girl subjected to horrific abuse and isolation. The case study of Genie allowed researchers to study whether language learning was possible, even after missing critical periods for language development. Her case also served as an example of how scientific research may interfere with treatment and lead to further abuse of vulnerable individuals.

Such cases demonstrate how case research can be used to study things that researchers could not replicate in experimental settings. In Genie's case, her horrific abuse denied her the opportunity to learn a language at critical points in her development.

This is clearly not something researchers could ethically replicate, but conducting a case study on Genie allowed researchers to study phenomena that are otherwise impossible to reproduce.

There are a few different types of case studies that psychologists and other researchers might use:

• Collective case studies : These involve studying a group of individuals. Researchers might study a group of people in a certain setting or look at an entire community. For example, psychologists might explore how access to resources in a community has affected the collective mental well-being of those who live there.
• Descriptive case studies : These involve starting with a descriptive theory. The subjects are then observed, and the information gathered is compared to the pre-existing theory.
• Explanatory case studies : These   are often used to do causal investigations. In other words, researchers are interested in looking at factors that may have caused certain things to occur.
• Exploratory case studies : These are sometimes used as a prelude to further, more in-depth research. This allows researchers to gather more information before developing their research questions and hypotheses .
• Instrumental case studies : These occur when the individual or group allows researchers to understand more than what is initially obvious to observers.
• Intrinsic case studies : This type of case study is when the researcher has a personal interest in the case. Jean Piaget's observations of his own children are good examples of how an intrinsic case study can contribute to the development of a psychological theory.

The three main case study types often used are intrinsic, instrumental, and collective. Intrinsic case studies are useful for learning about unique cases. Instrumental case studies help look at an individual to learn more about a broader issue. A collective case study can be useful for looking at several cases simultaneously.

The type of case study that psychology researchers use depends on the unique characteristics of the situation and the case itself.

There are a number of different sources and methods that researchers can use to gather information about an individual or group. Six major sources that have been identified by researchers are:

• Archival records : Census records, survey records, and name lists are examples of archival records.
• Direct observation : This strategy involves observing the subject, often in a natural setting . While an individual observer is sometimes used, it is more common to utilize a group of observers.
• Documents : Letters, newspaper articles, administrative records, etc., are the types of documents often used as sources.
• Interviews : Interviews are one of the most important methods for gathering information in case studies. An interview can involve structured survey questions or more open-ended questions.
• Participant observation : When the researcher serves as a participant in events and observes the actions and outcomes, it is called participant observation.
• Physical artifacts : Tools, objects, instruments, and other artifacts are often observed during a direct observation of the subject.

If you have been directed to write a case study for a psychology course, be sure to check with your instructor for any specific guidelines you need to follow. If you are writing your case study for a professional publication, check with the publisher for their specific guidelines for submitting a case study.

Here is a general outline of what should be included in a case study.

Section 1: A Case History

This section will have the following structure and content:

Background information : The first section of your paper will present your client's background. Include factors such as age, gender, work, health status, family mental health history, family and social relationships, drug and alcohol history, life difficulties, goals, and coping skills and weaknesses.

Description of the presenting problem : In the next section of your case study, you will describe the problem or symptoms that the client presented with.

Describe any physical, emotional, or sensory symptoms reported by the client. Thoughts, feelings, and perceptions related to the symptoms should also be noted. Any screening or diagnostic assessments that are used should also be described in detail and all scores reported.

Your diagnosis : Provide your diagnosis and give the appropriate Diagnostic and Statistical Manual code. Explain how you reached your diagnosis, how the client's symptoms fit the diagnostic criteria for the disorder(s), or any possible difficulties in reaching a diagnosis.

Section 2: Treatment Plan

This portion of the paper will address the chosen treatment for the condition. This might also include the theoretical basis for the chosen treatment or any other evidence that might exist to support why this approach was chosen.

• Cognitive behavioral approach : Explain how a cognitive behavioral therapist would approach treatment. Offer background information on cognitive behavioral therapy and describe the treatment sessions, client response, and outcome of this type of treatment. Make note of any difficulties or successes encountered by your client during treatment.
• Humanistic approach : Describe a humanistic approach that could be used to treat your client, such as client-centered therapy . Provide information on the type of treatment you chose, the client's reaction to the treatment, and the end result of this approach. Explain why the treatment was successful or unsuccessful.
• Psychoanalytic approach : Describe how a psychoanalytic therapist would view the client's problem. Provide some background on the psychoanalytic approach and cite relevant references. Explain how psychoanalytic therapy would be used to treat the client, how the client would respond to therapy, and the effectiveness of this treatment approach.
• Pharmacological approach : If treatment primarily involves the use of medications, explain which medications were used and why. Provide background on the effectiveness of these medications and how monotherapy may compare with an approach that combines medications with therapy or other treatments.

This section of a case study should also include information about the treatment goals, process, and outcomes.

When you are writing a case study, you should also include a section where you discuss the case study itself, including the strengths and limitiations of the study. You should note how the findings of your case study might support previous research. 

In your discussion section, you should also describe some of the implications of your case study. What ideas or findings might require further exploration? How might researchers go about exploring some of these questions in additional studies?

Need More Tips?

Here are a few additional pointers to keep in mind when formatting your case study:

• Never refer to the subject of your case study as "the client." Instead, use their name or a pseudonym.
• Read examples of case studies to gain an idea about the style and format.
• Remember to use APA format when citing references .

Crowe S, Cresswell K, Robertson A, Huby G, Avery A, Sheikh A. The case study approach .  BMC Med Res Methodol . 2011;11:100.

Crowe S, Cresswell K, Robertson A, Huby G, Avery A, Sheikh A. The case study approach . BMC Med Res Methodol . 2011 Jun 27;11:100. doi:10.1186/1471-2288-11-100

Gagnon, Yves-Chantal.  The Case Study as Research Method: A Practical Handbook . Canada, Chicago Review Press Incorporated DBA Independent Pub Group, 2010.

Yin, Robert K. Case Study Research and Applications: Design and Methods . United States, SAGE Publications, 2017.

By Kendra Cherry, MSEd Kendra Cherry, MS, is a psychosocial rehabilitation specialist, psychology educator, and author of the "Everything Psychology Book."

• [email protected]

How to Write a Case Study: The Compelling Step-by-Step Guide

Is there a poignant pain point that needs to be addressed in your company or industry? Do you have a possible solution but want to test your theory? Why not turn this drive into a transformative learning experience and an opportunity to produce a high-quality business case study? However, before that occurs, you may wonder how to write a case study.

You may also be thinking about why you should produce one at all. Did you know that case studies are impactful and the fifth most used type of content in marketing , despite being more resource-intensive to produce?

Below, we’ll delve into what a case study is, its benefits, and how to approach business case study writing:

Definition of a Written case study and its Purpose

A case study is a research method that involves a detailed and comprehensive examination of a specific real-life situation. It’s often used in various fields, including business, education, economics, and sociology, to understand a complex issue better. 

It typically includes an in-depth analysis of the subject and an examination of its context and background information, incorporating data from multiple sources, such as interviews, observations, and existing literature. 

The ultimate aim is to provide a rich and detailed account of a situation to identify patterns and relationships, generate new insights and understanding, illustrate theories, or test hypotheses.

Importance of Business Case Study Writing

As such an in-depth exploration into a subject with potentially far-reaching consequences, a case study has benefits to offer various stakeholders in the organisation leading it.

• Business Founders: Use business case study writing to highlight real-life examples of companies or individuals who have benefited from their products or services, providing potential customers with a tangible demonstration of the value their business can bring. It can be effective for attracting new clients or investors by showcasing thought leadership and building trust and credibility.
• Marketers through case studies and encourage them to take action: Marketers use a case studies writer to showcase the success of a particular product, service, or marketing campaign. They can use persuasive storytelling to engage the reader, whether it’s consumers, clients, or potential partners.
• Researchers: They allow researchers to gain insight into real-world scenarios, explore a variety of perspectives, and develop a nuanced understanding of the factors that contribute to success or failure. Additionally, case studies provide practical business recommendations and help build a body of knowledge in a particular field.

How to Write a Case Study – The Key Elements 

Considering how to write a case study can seem overwhelming at first. However, looking at it in terms of its constituent parts will help you to get started, focus on the key issue(s), and execute it efficiently and effectively.

Problem or Challenge Statement

A problem statement concisely describes a specific issue or problem that a written case study aims to address. It sets the stage for the rest of the case study and provides context for the reader. 

Here are some steps to help you write a case study problem statement:

• Identify the problem or issue that the case study will focus on.
• Research the problem to better understand its context, causes, and effects.
• Define the problem clearly and concisely. Be specific and avoid generalisations.
• State the significance of the problem: Explain why the issue is worth solving. Consider the impact it has on the individual, organisation, or industry.
• Provide background information that will help the reader understand the context of the problem.
• Keep it concise: A problem statement should be brief and to the point. Avoid going into too much detail – leave this for the body of the case study!

Here is an example of a problem statement for a case study:

“ The XYZ Company is facing a problem with declining sales and increasing customer complaints. Despite improving the customer experience, the company has yet to reverse the trend . This case study will examine the causes of the problem and propose solutions to improve sales and customer satisfaction. “

Solutions and interventions

Business case study writing provides a solution or intervention that identifies the best course of action to address the problem or issue described in the problem statement. 

Here are some steps to help you write a case study solution or intervention:

• Identify the objective , which should be directly related to the problem statement.
• Analyse the data, which could include data from interviews, observations, and existing literature.
• Evaluate alternatives that have been proposed or implemented in similar situations, considering their strengths, weaknesses, and impact.
• Choose the best solution based on the objective and data analysis. Remember to consider factors such as feasibility, cost, and potential impact.
• Justify the solution by explaining how it addresses the problem and why it’s the best solution with supportive evidence.
• Provide a detailed, step-by-step plan of action that considers the resources required, timeline, and expected outcomes.

Example of a solution or intervention for a case study:

“ To address the problem of declining sales and increasing customer complaints at the XYZ Company, we propose a comprehensive customer experience improvement program. “

“ This program will involve the following steps:

• Conducting customer surveys to gather feedback and identify areas for improvement
• Implementing training programs for employees to improve customer service skills
• Revising the company’s product offerings to meet customer needs better
• Implementing a customer loyalty program to encourage repeat business “

“ These steps will improve customer satisfaction and increase sales. We expect a 10% increase in sales within the first year of implementation, based on similar programs implemented by other companies in the industry. “

Possible Results and outcomes

Writing case study results and outcomes involves presenting the impact of the proposed solution or intervention. 

Here are some steps to help you write case study results and outcomes:

• Evaluate the solution by measuring its effectiveness in addressing the problem statement. That could involve collecting data, conducting surveys, or monitoring key performance indicators.
• Present the results clearly and concisely, using graphs, charts, and tables to represent the data where applicable visually. Be sure to include both quantitative and qualitative results.
• Compare the results to the expectations set in the solution or intervention section. Explain any discrepancies and why they occurred.
• Discuss the outcomes and impact of the solution, considering the benefits and drawbacks and what lessons can be learned.
• Provide recommendations for future action based on the results. For example, what changes should be made to improve the solution, or what additional steps should be taken?

Example of results and outcomes for a case study:

“ The customer experience improvement program implemented at the XYZ Company was successful. We found significant improvement in employee health and productivity. The program, which included on-site exercise classes and healthy food options, led to a 25% decrease in employee absenteeism and a 15% increase in productivity . “

“ Employee satisfaction with the program was high, with 90% reporting an improved work-life balance. Despite initial costs, the program proved to be cost-effective in the long run, with decreased healthcare costs and increased employee retention. The company plans to continue the program and explore expanding it to other offices .”

Case Study Key takeaways

Key takeaways are the most important and relevant insights and lessons that can be drawn from a case study. Key takeaways can help readers understand the most significant outcomes and impacts of the solution or intervention. 

Here are some steps to help you write case study key takeaways:

• Summarise the problem that was addressed and the solution that was proposed.
• Highlight the most significant results from the case study.
• Identify the key insights and lessons , including what makes the case study unique and relevant to others.
• Consider the broader implications of the outcomes for the industry or field.
• Present the key takeaways clearly and concisely , using bullet points or a list format to make the information easy to understand.

Example of key takeaways for a case study:

• The customer experience improvement program at XYZ Company successfully increased customer satisfaction and sales.
• Employee training and product development were critical components of the program’s success.
• The program resulted in a 20% increase in repeat business, demonstrating the value of a customer loyalty program.
• Despite some initial challenges, the program proved cost-effective in the long run.
• The case study results demonstrate the importance of investing in customer experience to improve business outcomes.

Steps for a Case Study Writer to Follow

If you still feel lost, the good news is as a case studies writer; there is a blueprint you can follow to complete your work. It may be helpful at first to proceed step-by-step and let your research and analysis guide the process:

• Select a suitable case study subject: Ask yourself what the purpose of the business case study is. Is it to illustrate a specific problem and solution, showcase a success story, or demonstrate best practices in a particular field? Based on this, you can select a suitable subject by researching and evaluating various options.
• Research and gather information: We have already covered this in detail above. However, always ensure all data is relevant, valid, and comes from credible sources. Research is the crux of your written case study, and you can’t compromise on its quality.
• Develop a clear and concise problem statement: Follow the guide above, and don’t rush to finalise it. It will set the tone and lay the foundation for the entire study.
• Detail the solution or intervention: Follow the steps above to detail your proposed solution or intervention.
• Present the results and outcomes: Remember that a case study is an unbiased test of how effectively a particular solution addresses an issue. Not all case studies are meant to end in a resounding success. You can often learn more from a loss than a win.
• Include key takeaways and conclusions: Follow the steps above to detail your proposed business case study solution or intervention.

Tips for How to Write a Case Study

Here are some bonus tips for how to write a case study. These tips will help improve the quality of your work and the impact it will have on readers:

• Use a storytelling format: Just because a case study is research-based doesn’t mean it has to be boring and detached. Telling a story will engage readers and help them better identify with the problem statement and see the value in the outcomes. Framing it as a narrative in a real-world context will make it more relatable and memorable.
• Include quotes and testimonials from stakeholders: This will add credibility and depth to your written case study. It also helps improve engagement and will give your written work an emotional impact.
• Use visuals and graphics to support your narrative: Humans are better at processing visually presented data than endless walls of black-on-white text. Visual aids will make it easier to grasp key concepts and make your case study more engaging and enjoyable. It breaks up the text and allows readers to identify key findings and highlights quickly.
• Edit and revise your case study for clarity and impact: As a long and involved project, it can be easy to lose your narrative while in the midst of it. Multiple rounds of editing are vital to ensure your narrative holds, that your message gets across, and that your spelling and grammar are correct, of course!

Our Final Thoughts

A written case study can be a powerful tool in your writing arsenal. It’s a great way to showcase your knowledge in a particular business vertical, industry, or situation. Not only is it an effective way to build authority and engage an audience, but also to explore an important problem and the possible solutions to it. It’s a win-win, even if the proposed solution doesn’t have the outcome you expect. So now that you know more about how to write a case study, try it or talk to us for further guidance.

Are you ready to write your own case study?

Begin by bookmarking this article, so you can come back to it. And for more writing advice and support, read our resource guides  and  blog content . If you are unsure, please reach out with questions, and we will provide the answers or assistance you need.

Categorised in: Resources

This post was written by Premier Prose

© 2024 Copyright Premier Prose. Website Designed by Ubie

• Privacy Overview
• Strictly Necessary Cookies
• Cookie Policy

This website uses cookies so that we can provide you with the best user experience possible. Cookie information is stored in your browser and performs functions such as recognising you when you return to our website and helping our team to understand which sections of the website you find most interesting and useful.

Strictly Necessary Cookie should be enabled at all times so that we can save your preferences for cookie settings.

If you disable this cookie, we will not be able to save your preferences. This means that every time you visit this website you will need to enable or disable cookies again.

More information about our Cookie Policy

Do Your Students Know How to Analyze a Case—Really?

Explore more.

• Case Teaching
• Student Engagement

J ust as actors, athletes, and musicians spend thousands of hours practicing their craft, business students benefit from practicing their critical-thinking and decision-making skills. Students, however, often have limited exposure to real-world problem-solving scenarios; they need more opportunities to practice tackling tough business problems and deciding on—and executing—the best solutions.

To ensure students have ample opportunity to develop these critical-thinking and decision-making skills, we believe business faculty should shift from teaching mostly principles and ideas to mostly applications and practices. And in doing so, they should emphasize the case method, which simulates real-world management challenges and opportunities for students.

To help educators facilitate this shift and help students get the most out of case-based learning, we have developed a framework for analyzing cases. We call it PACADI (Problem, Alternatives, Criteria, Analysis, Decision, Implementation); it can improve learning outcomes by helping students better solve and analyze business problems, make decisions, and develop and implement strategy. Here, we’ll explain why we developed this framework, how it works, and what makes it an effective learning tool.

The Case for Cases: Helping Students Think Critically

Business students must develop critical-thinking and analytical skills, which are essential to their ability to make good decisions in functional areas such as marketing, finance, operations, and information technology, as well as to understand the relationships among these functions. For example, the decisions a marketing manager must make include strategic planning (segments, products, and channels); execution (digital messaging, media, branding, budgets, and pricing); and operations (integrated communications and technologies), as well as how to implement decisions across functional areas.

Faculty can use many types of cases to help students develop these skills. These include the prototypical “paper cases”; live cases , which feature guest lecturers such as entrepreneurs or corporate leaders and on-site visits; and multimedia cases , which immerse students into real situations. Most cases feature an explicit or implicit decision that a protagonist—whether it is an individual, a group, or an organization—must make.

For students new to learning by the case method—and even for those with case experience—some common issues can emerge; these issues can sometimes be a barrier for educators looking to ensure the best possible outcomes in their case classrooms. Unsure of how to dig into case analysis on their own, students may turn to the internet or rely on former students for “answers” to assigned cases. Or, when assigned to provide answers to assignment questions in teams, students might take a divide-and-conquer approach but not take the time to regroup and provide answers that are consistent with one other.

To help address these issues, which we commonly experienced in our classes, we wanted to provide our students with a more structured approach for how they analyze cases—and to really think about making decisions from the protagonists’ point of view. We developed the PACADI framework to address this need.

PACADI: A Six-Step Decision-Making Approach

The PACADI framework is a six-step decision-making approach that can be used in lieu of traditional end-of-case questions. It offers a structured, integrated, and iterative process that requires students to analyze case information, apply business concepts to derive valuable insights, and develop recommendations based on these insights.

Prior to beginning a PACADI assessment, which we’ll outline here, students should first prepare a two-paragraph summary—a situation analysis—that highlights the key case facts. Then, we task students with providing a five-page PACADI case analysis (excluding appendices) based on the following six steps.

Step 1: Problem definition. What is the major challenge, problem, opportunity, or decision that has to be made? If there is more than one problem, choose the most important one. Often when solving the key problem, other issues will surface and be addressed. The problem statement may be framed as a question; for example, How can brand X improve market share among millennials in Canada? Usually the problem statement has to be re-written several times during the analysis of a case as students peel back the layers of symptoms or causation.

Step 2: Alternatives. Identify in detail the strategic alternatives to address the problem; three to five options generally work best. Alternatives should be mutually exclusive, realistic, creative, and feasible given the constraints of the situation. Doing nothing or delaying the decision to a later date are not considered acceptable alternatives.

Step 3: Criteria. What are the key decision criteria that will guide decision-making? In a marketing course, for example, these may include relevant marketing criteria such as segmentation, positioning, advertising and sales, distribution, and pricing. Financial criteria useful in evaluating the alternatives should be included—for example, income statement variables, customer lifetime value, payback, etc. Students must discuss their rationale for selecting the decision criteria and the weights and importance for each factor.

Step 4: Analysis. Provide an in-depth analysis of each alternative based on the criteria chosen in step three. Decision tables using criteria as columns and alternatives as rows can be helpful. The pros and cons of the various choices as well as the short- and long-term implications of each may be evaluated. Best, worst, and most likely scenarios can also be insightful.

Step 5: Decision. Students propose their solution to the problem. This decision is justified based on an in-depth analysis. Explain why the recommendation made is the best fit for the criteria.

Step 6: Implementation plan. Sound business decisions may fail due to poor execution. To enhance the likeliness of a successful project outcome, students describe the key steps (activities) to implement the recommendation, timetable, projected costs, expected competitive reaction, success metrics, and risks in the plan.

“Students note that using the PACADI framework yields ‘aha moments’—they learned something surprising in the case that led them to think differently about the problem and their proposed solution.”

PACADI’s Benefits: Meaningfully and Thoughtfully Applying Business Concepts

The PACADI framework covers all of the major elements of business decision-making, including implementation, which is often overlooked. By stepping through the whole framework, students apply relevant business concepts and solve management problems via a systematic, comprehensive approach; they’re far less likely to surface piecemeal responses.

As students explore each part of the framework, they may realize that they need to make changes to a previous step. For instance, when working on implementation, students may realize that the alternative they selected cannot be executed or will not be profitable, and thus need to rethink their decision. Or, they may discover that the criteria need to be revised since the list of decision factors they identified is incomplete (for example, the factors may explain key marketing concerns but fail to address relevant financial considerations) or is unrealistic (for example, they suggest a 25 percent increase in revenues without proposing an increased promotional budget).

In addition, the PACADI framework can be used alongside quantitative assignments, in-class exercises, and business and management simulations. The structured, multi-step decision framework encourages careful and sequential analysis to solve business problems. Incorporating PACADI as an overarching decision-making method across different projects will ultimately help students achieve desired learning outcomes. As a practical “beyond-the-classroom” tool, the PACADI framework is not a contrived course assignment; it reflects the decision-making approach that managers, executives, and entrepreneurs exercise daily. Case analysis introduces students to the real-world process of making business decisions quickly and correctly, often with limited information. This framework supplies an organized and disciplined process that students can readily defend in writing and in class discussions.

PACADI in Action: An Example

Here’s an example of how students used the PACADI framework for a recent case analysis on CVS, a large North American drugstore chain.

The CVS Prescription for Customer Value*

PACADI Stage

Summary Response

How should CVS Health evolve from the “drugstore of your neighborhood” to the “drugstore of your future”?

Alternatives

A1. Kaizen (continuous improvement)

A2. Product development

A3. Market development

A4. Personalization (micro-targeting)

Criteria (include weights)

C1. Customer value: service, quality, image, and price (40%)

C2. Customer obsession (20%)

C3. Growth through related businesses (20%)

C4. Customer retention and customer lifetime value (20%)

Each alternative was analyzed by each criterion using a Customer Value Assessment Tool

Alternative 4 (A4): Personalization was selected. This is operationalized via: segmentation—move toward segment-of-1 marketing; geodemographics and lifestyle emphasis; predictive data analysis; relationship marketing; people, principles, and supply chain management; and exceptional customer service.

Implementation

Partner with leading medical school

Curbside pick-up

Pet pharmacy

E-newsletter for customers and employees

Employee incentive program

CVS beauty days

Expand to Latin America and Caribbean

Healthier/happier corner

Holiday toy drives/community outreach

*Source: A. Weinstein, Y. Rodriguez, K. Sims, R. Vergara, “The CVS Prescription for Superior Customer Value—A Case Study,” Back to the Future: Revisiting the Foundations of Marketing from Society for Marketing Advances, West Palm Beach, FL (November 2, 2018).

Results of Using the PACADI Framework

When faculty members at our respective institutions at Nova Southeastern University (NSU) and the University of North Carolina Wilmington have used the PACADI framework, our classes have been more structured and engaging. Students vigorously debate each element of their decision and note that this framework yields an “aha moment”—they learned something surprising in the case that led them to think differently about the problem and their proposed solution.

These lively discussions enhance individual and collective learning. As one external metric of this improvement, we have observed a 2.5 percent increase in student case grade performance at NSU since this framework was introduced.

Tips to Get Started

The PACADI approach works well in in-person, online, and hybrid courses. This is particularly important as more universities have moved to remote learning options. Because students have varied educational and cultural backgrounds, work experience, and familiarity with case analysis, we recommend that faculty members have students work on their first case using this new framework in small teams (two or three students). Additional analyses should then be solo efforts.

To use PACADI effectively in your classroom, we suggest the following:

Advise your students that your course will stress critical thinking and decision-making skills, not just course concepts and theory.

Use a varied mix of case studies. As marketing professors, we often address consumer and business markets; goods, services, and digital commerce; domestic and global business; and small and large companies in a single MBA course.

As a starting point, provide a short explanation (about 20 to 30 minutes) of the PACADI framework with a focus on the conceptual elements. You can deliver this face to face or through videoconferencing.

Give students an opportunity to practice the case analysis methodology via an ungraded sample case study. Designate groups of five to seven students to discuss the case and the six steps in breakout sessions (in class or via Zoom).

Ensure case analyses are weighted heavily as a grading component. We suggest 30–50 percent of the overall course grade.

Once cases are graded, debrief with the class on what they did right and areas needing improvement (30- to 40-minute in-person or Zoom session).

Encourage faculty teams that teach common courses to build appropriate instructional materials, grading rubrics, videos, sample cases, and teaching notes.

When selecting case studies, we have found that the best ones for PACADI analyses are about 15 pages long and revolve around a focal management decision. This length provides adequate depth yet is not protracted. Some of our tested and favorite marketing cases include Brand W , Hubspot , Kraft Foods Canada , TRSB(A) , and Whiskey & Cheddar .

Art Weinstein , Ph.D., is a professor of marketing at Nova Southeastern University, Fort Lauderdale, Florida. He has published more than 80 scholarly articles and papers and eight books on customer-focused marketing strategy. His latest book is Superior Customer Value—Finding and Keeping Customers in the Now Economy . Dr. Weinstein has consulted for many leading technology and service companies.

Herbert V. Brotspies , D.B.A., is an adjunct professor of marketing at Nova Southeastern University. He has over 30 years’ experience as a vice president in marketing, strategic planning, and acquisitions for Fortune 50 consumer products companies working in the United States and internationally. His research interests include return on marketing investment, consumer behavior, business-to-business strategy, and strategic planning.

John T. Gironda , Ph.D., is an assistant professor of marketing at the University of North Carolina Wilmington. His research has been published in Industrial Marketing Management, Psychology & Marketing , and Journal of Marketing Management . He has also presented at major marketing conferences including the American Marketing Association, Academy of Marketing Science, and Society for Marketing Advances.

Related Articles

We use cookies to understand how you use our site and to improve your experience, including personalizing content. Learn More . By continuing to use our site, you accept our use of cookies and revised Privacy Policy .

• SUGGESTED TOPICS
• The Magazine
• Newsletters
• Managing Yourself
• Managing Teams
• Work-life Balance
• The Big Idea
• Data & Visuals
• Case Selections
• HBR Learning
• Topic Feeds
• Account Settings
• Email Preferences

What the Case Study Method Really Teaches

• Nitin Nohria

Seven meta-skills that stick even if the cases fade from memory.

It’s been 100 years since Harvard Business School began using the case study method. Beyond teaching specific subject matter, the case study method excels in instilling meta-skills in students. This article explains the importance of seven such skills: preparation, discernment, bias recognition, judgement, collaboration, curiosity, and self-confidence.

During my decade as dean of Harvard Business School, I spent hundreds of hours talking with our alumni. To enliven these conversations, I relied on a favorite question: “What was the most important thing you learned from your time in our MBA program?”

• Nitin Nohria is the George F. Baker Jr. and Distinguished Service University Professor. He served as the 10th dean of Harvard Business School, from 2010 to 2020.

Partner Center

How to Write a Case Study Analysis

Before writing a case study analysis, it is important to identify a relevant subject and research problem. While preparing to write, the author should critically assess the potential problem and the need for in-depth analysis. For example, hidden problems, outdated information, or a feasible recommendation are all indications that a problem lends itself to a case study. The introduction should not only include a problem statement but should also note its importance, provide background information, supply a rationale for applying a case study method, and suggest potential advancement of knowledge in the given field.

Literature Review

The key purpose of the literature review in a case study analysis is to present the historical context of a problem and its background based on academic evidence. Synthesis of existing studies contributes to the subsequent substantial aspects that should be taken into account:

• Identify the context of the problem under consideration and locate related studies, showing the link between them. Each of the academic pieces used to write a case study should make a particular contribution to understanding or resolving the target problem.
• Connect all the studies together and provide a critical appraisal. One of the most common mistakes is to merely present existing evidence without any analysis or clarification of how one or another research investigation relates to the problem.
• Discover and discuss any gaps in the literature, demonstrating how the case study adds more value and credibility to the available evidence. For example, if the case study focuses on strategies used to promote feminism, it is possible to explore the gap of how this movement is developing in the Middle East, where it is not as evident as in Western countries.
• Identify conflicts and contradictory issues that can be found in the literature. This helps in coming closer to the resolution of the problem. If, for example, two different approaches are regarded as mutually exclusive in one study, and the same approaches are considered compatible in another, it is an evident conflict. A discussion of such contradictory issues should be placed in the case study to suggest feasible solutions.
• Locate the case study in the context of the literature and within the larger scale. More to the point, by synthesizing the pertinent literature and indicating the role of the case study, the researcher shows that he or she has made essential efforts toward addressing the problem.

In this section, it is important to clarify why a specific subject and problem were chosen for study. A range of subjects is possible, and the type chosen will impact how the method will be described. The key types of subjects include phenomena, places, persons, and events.

• The investigation of a phenomenon as a target of a case study implies that certain facts or circumstances exist and require change and improvement. The behavioral and social sciences often require the study of challenging issues such as the causes of high employee turnover or a low level of motivation on the part of managers. In such a case, cause-and-effect relationships should be established to evaluate the environment.
• If an accident or event composes the basis of the case study, its time and place will set the specifics of the research. A rare or critical event as well as any one of a number of common situations may be selected; in any case, a rationale should be provided to support the choice. As a rule, rare events require forging a new way of thinking regarding the occurrence, while dealing with a commonly encountered situation is associated with challenging existing hypotheses. In both types of cases, the following elements should be included in the case analysis: timeframe, circumstances, and consequences.
• A focus on a person as the subject of a study refers to scrutinizing the individual’s experience, relationships, and behaviors. For example, a discussion of Mark Zuckerberg as the creator of Facebook requires identifying the background, conflicts, and positive and negative consequences of his contributions to society.
• A place as the subject of a case study should be special, and it should be clear to readers why a particular area or neighborhood was chosen. What is, for example, the aim of focusing on China and Japan instead of the United States when exploring homelessness issues?

An important part of case study research or development in the field of the social and behavioral sciences involves discussing and interpreting findings. Therefore, after a thorough literature review, it is necessary to compare, reiterate, and revise the findings based on the experiences reported in previous studies along with the writer’s personal understanding of the subject studied.

• The discussion section may start with a brief summary of the findings that are of the greatest importance and particularly thought-provoking.
• The results should be assessed in terms of the hypothesis and objectives of the research. Briefly reiterating these, indicate whether the data obtained have confirmed the hypothesis, the goal has been achieved, and the research tasks have been addressed.
• The researcher should indicate how the findings are consistent with the conclusions of other researchers and theories described in the literature review. Comparing and contrasting the findings with the articles mentioned in the literature review will be beneficial as this will support the importance of the new study.
• To identify the possibilities and ways of applying the results to solve practical problems, recommendations for practical implementation should be as specific as possible and describe actions that organizations or individuals can take to put the findings into practice.
• The advantages of the research methodology used and the limitations of the generalization of the results obtained should be clarified. Such a discussion is especially necessary in a case study since it demonstrates an understanding of methodological nuances.
• It is advantageous to outline the prospects and suggestions for further research on the given problem to expand the scope of application of the results. It is also crucial to point out possible ways to improve the methodology and organization of a case study analysis.

In the conclusion, restating the key findings and noting their importance is essential to allow readers to understand the key points of the case study report. The conclusion should be written concisely, including a description of the problem and elaborating on solutions while presenting the expected future effect of the actions proposed for practical implementation. While the body of the case study paper focuses on details, the conclusion contains a generalized scope of the research problem. However, overgeneralization as well as failure to specify limitations should be avoided. Only the documentary evidence serves as a basis for assumptions, and the statement of limitations will help preclude unjustified conclusions.

• How to Write a Discussion Board Post
• How to Write a Case Study Like a Pro
• How to Write a Capstone Project Like an Expert
• Emails (Email Etiquette)
• Grant Proposal
• How to Write a Successful Motivation Letter

Organizing Your Social Sciences Research Assignments

• Annotated Bibliography
• Analyzing a Scholarly Journal Article
• Group Presentations
• Dealing with Nervousness
• Using Visual Aids
• Grading Someone Else's Paper
• Types of Structured Group Activities
• Group Project Survival Skills
• Leading a Class Discussion
• Multiple Book Review Essay
• Reviewing Collected Works
• Writing a Case Analysis Paper
• Writing a Case Study
• About Informed Consent
• Writing Field Notes
• Writing a Policy Memo
• Writing a Reflective Paper
• Writing a Research Proposal
• Generative AI and Writing
• Acknowledgments

A case study research paper examines a person, place, event, condition, phenomenon, or other type of subject of analysis in order to extrapolate  key themes and results that help predict future trends, illuminate previously hidden issues that can be applied to practice, and/or provide a means for understanding an important research problem with greater clarity. A case study research paper usually examines a single subject of analysis, but case study papers can also be designed as a comparative investigation that shows relationships between two or more subjects. The methods used to study a case can rest within a quantitative, qualitative, or mixed-method investigative paradigm.

Case Studies. Writing@CSU. Colorado State University; Mills, Albert J. , Gabrielle Durepos, and Eiden Wiebe, editors. Encyclopedia of Case Study Research . Thousand Oaks, CA: SAGE Publications, 2010 ; “What is a Case Study?” In Swanborn, Peter G. Case Study Research: What, Why and How? London: SAGE, 2010.

How to Approach Writing a Case Study Research Paper

General information about how to choose a topic to investigate can be found under the " Choosing a Research Problem " tab in the Organizing Your Social Sciences Research Paper writing guide. Review this page because it may help you identify a subject of analysis that can be investigated using a case study design.

However, identifying a case to investigate involves more than choosing the research problem . A case study encompasses a problem contextualized around the application of in-depth analysis, interpretation, and discussion, often resulting in specific recommendations for action or for improving existing conditions. As Seawright and Gerring note, practical considerations such as time and access to information can influence case selection, but these issues should not be the sole factors used in describing the methodological justification for identifying a particular case to study. Given this, selecting a case includes considering the following:

• The case represents an unusual or atypical example of a research problem that requires more in-depth analysis? Cases often represent a topic that rests on the fringes of prior investigations because the case may provide new ways of understanding the research problem. For example, if the research problem is to identify strategies to improve policies that support girl's access to secondary education in predominantly Muslim nations, you could consider using Azerbaijan as a case study rather than selecting a more obvious nation in the Middle East. Doing so may reveal important new insights into recommending how governments in other predominantly Muslim nations can formulate policies that support improved access to education for girls.
• The case provides important insight or illuminate a previously hidden problem? In-depth analysis of a case can be based on the hypothesis that the case study will reveal trends or issues that have not been exposed in prior research or will reveal new and important implications for practice. For example, anecdotal evidence may suggest drug use among homeless veterans is related to their patterns of travel throughout the day. Assuming prior studies have not looked at individual travel choices as a way to study access to illicit drug use, a case study that observes a homeless veteran could reveal how issues of personal mobility choices facilitate regular access to illicit drugs. Note that it is important to conduct a thorough literature review to ensure that your assumption about the need to reveal new insights or previously hidden problems is valid and evidence-based.
• The case challenges and offers a counter-point to prevailing assumptions? Over time, research on any given topic can fall into a trap of developing assumptions based on outdated studies that are still applied to new or changing conditions or the idea that something should simply be accepted as "common sense," even though the issue has not been thoroughly tested in current practice. A case study analysis may offer an opportunity to gather evidence that challenges prevailing assumptions about a research problem and provide a new set of recommendations applied to practice that have not been tested previously. For example, perhaps there has been a long practice among scholars to apply a particular theory in explaining the relationship between two subjects of analysis. Your case could challenge this assumption by applying an innovative theoretical framework [perhaps borrowed from another discipline] to explore whether this approach offers new ways of understanding the research problem. Taking a contrarian stance is one of the most important ways that new knowledge and understanding develops from existing literature.
• The case provides an opportunity to pursue action leading to the resolution of a problem? Another way to think about choosing a case to study is to consider how the results from investigating a particular case may result in findings that reveal ways in which to resolve an existing or emerging problem. For example, studying the case of an unforeseen incident, such as a fatal accident at a railroad crossing, can reveal hidden issues that could be applied to preventative measures that contribute to reducing the chance of accidents in the future. In this example, a case study investigating the accident could lead to a better understanding of where to strategically locate additional signals at other railroad crossings so as to better warn drivers of an approaching train, particularly when visibility is hindered by heavy rain, fog, or at night.
• The case offers a new direction in future research? A case study can be used as a tool for an exploratory investigation that highlights the need for further research about the problem. A case can be used when there are few studies that help predict an outcome or that establish a clear understanding about how best to proceed in addressing a problem. For example, after conducting a thorough literature review [very important!], you discover that little research exists showing the ways in which women contribute to promoting water conservation in rural communities of east central Africa. A case study of how women contribute to saving water in a rural village of Uganda can lay the foundation for understanding the need for more thorough research that documents how women in their roles as cooks and family caregivers think about water as a valuable resource within their community. This example of a case study could also point to the need for scholars to build new theoretical frameworks around the topic [e.g., applying feminist theories of work and family to the issue of water conservation].

Eisenhardt, Kathleen M. “Building Theories from Case Study Research.” Academy of Management Review 14 (October 1989): 532-550; Emmel, Nick. Sampling and Choosing Cases in Qualitative Research: A Realist Approach . Thousand Oaks, CA: SAGE Publications, 2013; Gerring, John. “What Is a Case Study and What Is It Good for?” American Political Science Review 98 (May 2004): 341-354; Mills, Albert J. , Gabrielle Durepos, and Eiden Wiebe, editors. Encyclopedia of Case Study Research . Thousand Oaks, CA: SAGE Publications, 2010; Seawright, Jason and John Gerring. "Case Selection Techniques in Case Study Research." Political Research Quarterly 61 (June 2008): 294-308.

Structure and Writing Style

The purpose of a paper in the social sciences designed around a case study is to thoroughly investigate a subject of analysis in order to reveal a new understanding about the research problem and, in so doing, contributing new knowledge to what is already known from previous studies. In applied social sciences disciplines [e.g., education, social work, public administration, etc.], case studies may also be used to reveal best practices, highlight key programs, or investigate interesting aspects of professional work.

In general, the structure of a case study research paper is not all that different from a standard college-level research paper. However, there are subtle differences you should be aware of. Here are the key elements to organizing and writing a case study research paper.

I.  Introduction

As with any research paper, your introduction should serve as a roadmap for your readers to ascertain the scope and purpose of your study . The introduction to a case study research paper, however, should not only describe the research problem and its significance, but you should also succinctly describe why the case is being used and how it relates to addressing the problem. The two elements should be linked. With this in mind, a good introduction answers these four questions:

• What is being studied? Describe the research problem and describe the subject of analysis [the case] you have chosen to address the problem. Explain how they are linked and what elements of the case will help to expand knowledge and understanding about the problem.
• Why is this topic important to investigate? Describe the significance of the research problem and state why a case study design and the subject of analysis that the paper is designed around is appropriate in addressing the problem.
• What did we know about this topic before I did this study? Provide background that helps lead the reader into the more in-depth literature review to follow. If applicable, summarize prior case study research applied to the research problem and why it fails to adequately address the problem. Describe why your case will be useful. If no prior case studies have been used to address the research problem, explain why you have selected this subject of analysis.
• How will this study advance new knowledge or new ways of understanding? Explain why your case study will be suitable in helping to expand knowledge and understanding about the research problem.

Each of these questions should be addressed in no more than a few paragraphs. Exceptions to this can be when you are addressing a complex research problem or subject of analysis that requires more in-depth background information.

II.  Literature Review

The literature review for a case study research paper is generally structured the same as it is for any college-level research paper. The difference, however, is that the literature review is focused on providing background information and  enabling historical interpretation of the subject of analysis in relation to the research problem the case is intended to address . This includes synthesizing studies that help to:

• Place relevant works in the context of their contribution to understanding the case study being investigated . This would involve summarizing studies that have used a similar subject of analysis to investigate the research problem. If there is literature using the same or a very similar case to study, you need to explain why duplicating past research is important [e.g., conditions have changed; prior studies were conducted long ago, etc.].
• Describe the relationship each work has to the others under consideration that informs the reader why this case is applicable . Your literature review should include a description of any works that support using the case to investigate the research problem and the underlying research questions.
• Identify new ways to interpret prior research using the case study . If applicable, review any research that has examined the research problem using a different research design. Explain how your use of a case study design may reveal new knowledge or a new perspective or that can redirect research in an important new direction.
• Resolve conflicts amongst seemingly contradictory previous studies . This refers to synthesizing any literature that points to unresolved issues of concern about the research problem and describing how the subject of analysis that forms the case study can help resolve these existing contradictions.
• Point the way in fulfilling a need for additional research . Your review should examine any literature that lays a foundation for understanding why your case study design and the subject of analysis around which you have designed your study may reveal a new way of approaching the research problem or offer a perspective that points to the need for additional research.
• Expose any gaps that exist in the literature that the case study could help to fill . Summarize any literature that not only shows how your subject of analysis contributes to understanding the research problem, but how your case contributes to a new way of understanding the problem that prior research has failed to do.
• Locate your own research within the context of existing literature [very important!] . Collectively, your literature review should always place your case study within the larger domain of prior research about the problem. The overarching purpose of reviewing pertinent literature in a case study paper is to demonstrate that you have thoroughly identified and synthesized prior studies in relation to explaining the relevance of the case in addressing the research problem.

III.  Method

In this section, you explain why you selected a particular case [i.e., subject of analysis] and the strategy you used to identify and ultimately decide that your case was appropriate in addressing the research problem. The way you describe the methods used varies depending on the type of subject of analysis that constitutes your case study.

If your subject of analysis is an incident or event . In the social and behavioral sciences, the event or incident that represents the case to be studied is usually bounded by time and place, with a clear beginning and end and with an identifiable location or position relative to its surroundings. The subject of analysis can be a rare or critical event or it can focus on a typical or regular event. The purpose of studying a rare event is to illuminate new ways of thinking about the broader research problem or to test a hypothesis. Critical incident case studies must describe the method by which you identified the event and explain the process by which you determined the validity of this case to inform broader perspectives about the research problem or to reveal new findings. However, the event does not have to be a rare or uniquely significant to support new thinking about the research problem or to challenge an existing hypothesis. For example, Walo, Bull, and Breen conducted a case study to identify and evaluate the direct and indirect economic benefits and costs of a local sports event in the City of Lismore, New South Wales, Australia. The purpose of their study was to provide new insights from measuring the impact of a typical local sports event that prior studies could not measure well because they focused on large "mega-events." Whether the event is rare or not, the methods section should include an explanation of the following characteristics of the event: a) when did it take place; b) what were the underlying circumstances leading to the event; and, c) what were the consequences of the event in relation to the research problem.

If your subject of analysis is a person. Explain why you selected this particular individual to be studied and describe what experiences they have had that provide an opportunity to advance new understandings about the research problem. Mention any background about this person which might help the reader understand the significance of their experiences that make them worthy of study. This includes describing the relationships this person has had with other people, institutions, and/or events that support using them as the subject for a case study research paper. It is particularly important to differentiate the person as the subject of analysis from others and to succinctly explain how the person relates to examining the research problem [e.g., why is one politician in a particular local election used to show an increase in voter turnout from any other candidate running in the election]. Note that these issues apply to a specific group of people used as a case study unit of analysis [e.g., a classroom of students].

If your subject of analysis is a place. In general, a case study that investigates a place suggests a subject of analysis that is unique or special in some way and that this uniqueness can be used to build new understanding or knowledge about the research problem. A case study of a place must not only describe its various attributes relevant to the research problem [e.g., physical, social, historical, cultural, economic, political], but you must state the method by which you determined that this place will illuminate new understandings about the research problem. It is also important to articulate why a particular place as the case for study is being used if similar places also exist [i.e., if you are studying patterns of homeless encampments of veterans in open spaces, explain why you are studying Echo Park in Los Angeles rather than Griffith Park?]. If applicable, describe what type of human activity involving this place makes it a good choice to study [e.g., prior research suggests Echo Park has more homeless veterans].

If your subject of analysis is a phenomenon. A phenomenon refers to a fact, occurrence, or circumstance that can be studied or observed but with the cause or explanation to be in question. In this sense, a phenomenon that forms your subject of analysis can encompass anything that can be observed or presumed to exist but is not fully understood. In the social and behavioral sciences, the case usually focuses on human interaction within a complex physical, social, economic, cultural, or political system. For example, the phenomenon could be the observation that many vehicles used by ISIS fighters are small trucks with English language advertisements on them. The research problem could be that ISIS fighters are difficult to combat because they are highly mobile. The research questions could be how and by what means are these vehicles used by ISIS being supplied to the militants and how might supply lines to these vehicles be cut off? How might knowing the suppliers of these trucks reveal larger networks of collaborators and financial support? A case study of a phenomenon most often encompasses an in-depth analysis of a cause and effect that is grounded in an interactive relationship between people and their environment in some way.

NOTE:   The choice of the case or set of cases to study cannot appear random. Evidence that supports the method by which you identified and chose your subject of analysis should clearly support investigation of the research problem and linked to key findings from your literature review. Be sure to cite any studies that helped you determine that the case you chose was appropriate for examining the problem.

IV.  Discussion

The main elements of your discussion section are generally the same as any research paper, but centered around interpreting and drawing conclusions about the key findings from your analysis of the case study. Note that a general social sciences research paper may contain a separate section to report findings. However, in a paper designed around a case study, it is common to combine a description of the results with the discussion about their implications. The objectives of your discussion section should include the following:

Reiterate the Research Problem/State the Major Findings Briefly reiterate the research problem you are investigating and explain why the subject of analysis around which you designed the case study were used. You should then describe the findings revealed from your study of the case using direct, declarative, and succinct proclamation of the study results. Highlight any findings that were unexpected or especially profound.

Explain the Meaning of the Findings and Why They are Important Systematically explain the meaning of your case study findings and why you believe they are important. Begin this part of the section by repeating what you consider to be your most important or surprising finding first, then systematically review each finding. Be sure to thoroughly extrapolate what your analysis of the case can tell the reader about situations or conditions beyond the actual case that was studied while, at the same time, being careful not to misconstrue or conflate a finding that undermines the external validity of your conclusions.

Relate the Findings to Similar Studies No study in the social sciences is so novel or possesses such a restricted focus that it has absolutely no relation to previously published research. The discussion section should relate your case study results to those found in other studies, particularly if questions raised from prior studies served as the motivation for choosing your subject of analysis. This is important because comparing and contrasting the findings of other studies helps support the overall importance of your results and it highlights how and in what ways your case study design and the subject of analysis differs from prior research about the topic.

Consider Alternative Explanations of the Findings Remember that the purpose of social science research is to discover and not to prove. When writing the discussion section, you should carefully consider all possible explanations revealed by the case study results, rather than just those that fit your hypothesis or prior assumptions and biases. Be alert to what the in-depth analysis of the case may reveal about the research problem, including offering a contrarian perspective to what scholars have stated in prior research if that is how the findings can be interpreted from your case.

Acknowledge the Study's Limitations You can state the study's limitations in the conclusion section of your paper but describing the limitations of your subject of analysis in the discussion section provides an opportunity to identify the limitations and explain why they are not significant. This part of the discussion section should also note any unanswered questions or issues your case study could not address. More detailed information about how to document any limitations to your research can be found here .

Suggest Areas for Further Research Although your case study may offer important insights about the research problem, there are likely additional questions related to the problem that remain unanswered or findings that unexpectedly revealed themselves as a result of your in-depth analysis of the case. Be sure that the recommendations for further research are linked to the research problem and that you explain why your recommendations are valid in other contexts and based on the original assumptions of your study.

V.  Conclusion

As with any research paper, you should summarize your conclusion in clear, simple language; emphasize how the findings from your case study differs from or supports prior research and why. Do not simply reiterate the discussion section. Provide a synthesis of key findings presented in the paper to show how these converge to address the research problem. If you haven't already done so in the discussion section, be sure to document the limitations of your case study and any need for further research.

The function of your paper's conclusion is to: 1) reiterate the main argument supported by the findings from your case study; 2) state clearly the context, background, and necessity of pursuing the research problem using a case study design in relation to an issue, controversy, or a gap found from reviewing the literature; and, 3) provide a place to persuasively and succinctly restate the significance of your research problem, given that the reader has now been presented with in-depth information about the topic.

Consider the following points to help ensure your conclusion is appropriate:

• If the argument or purpose of your paper is complex, you may need to summarize these points for your reader.
• If prior to your conclusion, you have not yet explained the significance of your findings or if you are proceeding inductively, use the conclusion of your paper to describe your main points and explain their significance.
• Move from a detailed to a general level of consideration of the case study's findings that returns the topic to the context provided by the introduction or within a new context that emerges from your case study findings.

Note that, depending on the discipline you are writing in or the preferences of your professor, the concluding paragraph may contain your final reflections on the evidence presented as it applies to practice or on the essay's central research problem. However, the nature of being introspective about the subject of analysis you have investigated will depend on whether you are explicitly asked to express your observations in this way.

Problems to Avoid

Overgeneralization One of the goals of a case study is to lay a foundation for understanding broader trends and issues applied to similar circumstances. However, be careful when drawing conclusions from your case study. They must be evidence-based and grounded in the results of the study; otherwise, it is merely speculation. Looking at a prior example, it would be incorrect to state that a factor in improving girls access to education in Azerbaijan and the policy implications this may have for improving access in other Muslim nations is due to girls access to social media if there is no documentary evidence from your case study to indicate this. There may be anecdotal evidence that retention rates were better for girls who were engaged with social media, but this observation would only point to the need for further research and would not be a definitive finding if this was not a part of your original research agenda.

Failure to Document Limitations No case is going to reveal all that needs to be understood about a research problem. Therefore, just as you have to clearly state the limitations of a general research study , you must describe the specific limitations inherent in the subject of analysis. For example, the case of studying how women conceptualize the need for water conservation in a village in Uganda could have limited application in other cultural contexts or in areas where fresh water from rivers or lakes is plentiful and, therefore, conservation is understood more in terms of managing access rather than preserving access to a scarce resource.

Failure to Extrapolate All Possible Implications Just as you don't want to over-generalize from your case study findings, you also have to be thorough in the consideration of all possible outcomes or recommendations derived from your findings. If you do not, your reader may question the validity of your analysis, particularly if you failed to document an obvious outcome from your case study research. For example, in the case of studying the accident at the railroad crossing to evaluate where and what types of warning signals should be located, you failed to take into consideration speed limit signage as well as warning signals. When designing your case study, be sure you have thoroughly addressed all aspects of the problem and do not leave gaps in your analysis that leave the reader questioning the results.

Case Studies. Writing@CSU. Colorado State University; Gerring, John. Case Study Research: Principles and Practices . New York: Cambridge University Press, 2007; Merriam, Sharan B. Qualitative Research and Case Study Applications in Education . Rev. ed. San Francisco, CA: Jossey-Bass, 1998; Miller, Lisa L. “The Use of Case Studies in Law and Social Science Research.” Annual Review of Law and Social Science 14 (2018): TBD; Mills, Albert J., Gabrielle Durepos, and Eiden Wiebe, editors. Encyclopedia of Case Study Research . Thousand Oaks, CA: SAGE Publications, 2010; Putney, LeAnn Grogan. "Case Study." In Encyclopedia of Research Design , Neil J. Salkind, editor. (Thousand Oaks, CA: SAGE Publications, 2010), pp. 116-120; Simons, Helen. Case Study Research in Practice . London: SAGE Publications, 2009;  Kratochwill,  Thomas R. and Joel R. Levin, editors. Single-Case Research Design and Analysis: New Development for Psychology and Education .  Hilldsale, NJ: Lawrence Erlbaum Associates, 1992; Swanborn, Peter G. Case Study Research: What, Why and How? London : SAGE, 2010; Yin, Robert K. Case Study Research: Design and Methods . 6th edition. Los Angeles, CA, SAGE Publications, 2014; Walo, Maree, Adrian Bull, and Helen Breen. “Achieving Economic Benefits at Local Events: A Case Study of a Local Sports Event.” Festival Management and Event Tourism 4 (1996): 95-106.

Writing Tip

At Least Five Misconceptions about Case Study Research

Social science case studies are often perceived as limited in their ability to create new knowledge because they are not randomly selected and findings cannot be generalized to larger populations. Flyvbjerg examines five misunderstandings about case study research and systematically "corrects" each one. To quote, these are:

Misunderstanding 1 :  General, theoretical [context-independent] knowledge is more valuable than concrete, practical [context-dependent] knowledge. Misunderstanding 2 :  One cannot generalize on the basis of an individual case; therefore, the case study cannot contribute to scientific development. Misunderstanding 3 :  The case study is most useful for generating hypotheses; that is, in the first stage of a total research process, whereas other methods are more suitable for hypotheses testing and theory building. Misunderstanding 4 :  The case study contains a bias toward verification, that is, a tendency to confirm the researcher’s preconceived notions. Misunderstanding 5 :  It is often difficult to summarize and develop general propositions and theories on the basis of specific case studies [p. 221].

While writing your paper, think introspectively about how you addressed these misconceptions because to do so can help you strengthen the validity and reliability of your research by clarifying issues of case selection, the testing and challenging of existing assumptions, the interpretation of key findings, and the summation of case outcomes. Think of a case study research paper as a complete, in-depth narrative about the specific properties and key characteristics of your subject of analysis applied to the research problem.

Flyvbjerg, Bent. “Five Misunderstandings About Case-Study Research.” Qualitative Inquiry 12 (April 2006): 219-245.

• << Previous: Writing a Case Analysis Paper
• Next: Writing a Field Report >>
• Last Updated: Jun 3, 2024 9:44 AM
• URL: https://libguides.usc.edu/writingguide/assignments

• College Essay
• Argumentative Essay
• Expository Essay
• Narrative Essay
• Descriptive Essay
• Scholarship Essay
• Admission Essay
• Reflective Essay
• Nursing Essay
• Economics Essay

Assignments

• Term Papers
• Research Papers
• Case Studies
• Dissertation
• Presentation
• Editing Help
• Cheap Essay Writing
• How to Order

Writing A Case Study

Case Study Examples

Brilliant Case Study Examples and Templates For Your Help

15 min read

People also read

A Complete Case Study Writing Guide With Examples

Simple Case Study Format for Students to Follow

Understand the Types of Case Study Here

It’s no surprise that writing a case study is one of the most challenging academic tasks for students. You’re definitely not alone here!

Most people don't realize that there are specific guidelines to follow when writing a case study. If you don't know where to start, it's easy to get overwhelmed and give up before you even begin.

Don't worry! Let us help you out!

We've collected over 25 free case study examples with solutions just for you. These samples with solutions will help you win over your panel and score high marks on your case studies.

So, what are you waiting for? Let's dive in and learn the secrets to writing a successful case study.

• 1. An Overview of Case Studies
• 2. Case Study Examples for Students
• 3. Business Case Study Examples
• 4. Medical Case Study Examples
• 5. Psychology Case Study Examples 
• 6. Sales Case Study Examples
• 7. Interview Case Study Examples
• 8. Marketing Case Study Examples
• 9. Tips to Write a Good Case Study

An Overview of Case Studies

A case study is a research method used to study a particular individual, group, or situation in depth. It involves analyzing and interpreting data from a variety of sources to gain insight into the subject being studied. 

Case studies are often used in psychology, business, and education to explore complicated problems and find solutions. They usually have detailed descriptions of the subject, background info, and an analysis of the main issues.

The goal of a case study is to provide a comprehensive understanding of the subject. Typically, case studies can be divided into three parts, challenges, solutions, and results. 

Here is a case study sample PDF so you can have a clearer understanding of what a case study actually is:

Case Study Sample PDF

How to Write a Case Study Examples

Learn how to write a case study with the help of our comprehensive case study guide.

Case Study Examples for Students

Quite often, students are asked to present case studies in their academic journeys. The reason instructors assign case studies is for students to sharpen their critical analysis skills, understand how companies make profits, etc.

Below are some case study examples in research, suitable for students:

Case Study Example in Software Engineering

Qualitative Research Case Study Sample

Software Quality Assurance Case Study

Social Work Case Study Example

Ethical Case Study

Case Study Example PDF

These examples can guide you on how to structure and format your own case studies.

Struggling with formatting your case study? Check this case study format guide and perfect your document’s structure today.

Business Case Study Examples

A business case study examines a business’s specific challenge or goal and how it should be solved. Business case studies usually focus on several details related to the initial challenge and proposed solution. 

To help you out, here are some samples so you can create case studies that are related to businesses: 

Here are some more business case study examples:

Business Case Studies PDF

Business Case Studies Example

Typically, a business case study discovers one of your customer's stories and how you solved a problem for them. It allows your prospects to see how your solutions address their needs. 

Medical Case Study Examples

Medical case studies are an essential part of medical education. They help students to understand how to diagnose and treat patients. 

Here are some medical case study examples to help you.

Medical Case Study Example

Nursing Case Study Example

Want to understand the various types of case studies? Check out our types of case study blog to select the perfect type.

Psychology Case Study Examples 

Case studies are a great way of investigating individuals with psychological abnormalities. This is why it is a very common assignment in psychology courses. 

By examining all the aspects of your subject’s life, you discover the possible causes of exhibiting such behavior. 

For your help, here are some interesting psychology case study examples:

Psychology Case Study Example

Mental Health Case Study Example

Sales Case Study Examples

Case studies are important tools for sales teams’ performance improvement. By examining sales successes, teams can gain insights into effective strategies and create action plans to employ similar tactics.

By researching case studies of successful sales campaigns, sales teams can more accurately identify challenges and develop solutions.

Sales Case Study Example

Interview Case Study Examples

Interview case studies provide businesses with invaluable information. This data allows them to make informed decisions related to certain markets or subjects.

Interview Case Study Example

Marketing Case Study Examples

Marketing case studies are real-life stories that showcase how a business solves a problem. They typically discuss how a business achieves a goal using a specific marketing strategy or tactic.

They typically describe a challenge faced by a business, the solution implemented, and the results achieved.

This is a short sample marketing case study for you to get an idea of what an actual marketing case study looks like.

 Here are some more popular marketing studies that show how companies use case studies as a means of marketing and promotion:

“Chevrolet Discover the Unexpected” by Carol H. Williams

This case study explores Chevrolet's “ DTU Journalism Fellows ” program. The case study uses the initials “DTU” to generate interest and encourage readers to learn more. 

Multiple types of media, such as images and videos, are used to explain the challenges faced. The case study concludes with an overview of the achievements that were met.

Key points from the case study include:

• Using a well-known brand name in the title can create interest.
• Combining different media types, such as headings, images, and videos, can help engage readers and make the content more memorable.
• Providing a summary of the key achievements at the end of the case study can help readers better understand the project's impact.

“The Met” by Fantasy

“ The Met ” by Fantasy is a fictional redesign of the Metropolitan Museum of Art in New York City, created by the design studio Fantasy. The case study clearly and simply showcases the museum's website redesign.

The Met emphasizes the website’s features and interface by showcasing each section of the interface individually, allowing the readers to concentrate on the significant elements.

For those who prefer text, each feature includes an objective description. The case study also includes a “Contact Us” call-to-action at the bottom of the page, inviting visitors to contact the company.

Key points from this “The Met” include:

• Keeping the case study simple and clean can help readers focus on the most important aspects.
• Presenting the features and solutions with a visual showcase can be more effective than writing a lot of text.
• Including a clear call-to-action at the end of the case study can encourage visitors to contact the company for more information.

“Better Experiences for All” by Herman Miller

Herman Miller's minimalist approach to furniture design translates to their case study, “ Better Experiences for All ”, for a Dubai hospital. The page features a captivating video with closed-captioning and expandable text for accessibility.

The case study presents a wealth of information in a concise format, enabling users to grasp the complexities of the strategy with ease. It concludes with a client testimonial and a list of furniture items purchased from the brand.

Key points from the “Better Experiences” include:

• Make sure your case study is user-friendly by including accessibility features like closed captioning and expandable text.
• Include a list of products that were used in the project to guide potential customers.

“NetApp” by Evisort 

Evisort's case study on “ NetApp ” stands out for its informative and compelling approach. The study begins with a client-centric overview of NetApp, strategically directing attention to the client rather than the company or team involved.

The case study incorporates client quotes and explores NetApp’s challenges during COVID-19. Evisort showcases its value as a client partner by showing how its services supported NetApp through difficult times. 

• Provide an overview of the company in the client’s words, and put focus on the customer. 
• Highlight how your services can help clients during challenging times.
• Make your case study accessible by providing it in various formats.

“Red Sox Season Campaign,” by CTP Boston

The “ Red Sox Season Campaign ” showcases a perfect blend of different media, such as video, text, and images. Upon visiting the page, the video plays automatically, there are videos of Red Sox players, their images, and print ads that can be enlarged with a click.

The page features an intuitive design and invites viewers to appreciate CTP's well-rounded campaign for Boston's beloved baseball team. There’s also a CTA that prompts viewers to learn how CTP can create a similar campaign for their brand.

Some key points to take away from the “Red Sox Season Campaign”: 

• Including a variety of media such as video, images, and text can make your case study more engaging and compelling.
• Include a call-to-action at the end of your study that encourages viewers to take the next step towards becoming a customer or prospect.

“Airbnb + Zendesk” by Zendesk

The case study by Zendesk, titled “ Airbnb + Zendesk : Building a powerful solution together,” showcases a true partnership between Airbnb and Zendesk. 

The article begins with an intriguing opening statement, “Halfway around the globe is a place to stay with your name on it. At least for a weekend,” and uses stunning images of beautiful Airbnb locations to captivate readers.

Instead of solely highlighting Zendesk's product, the case study is crafted to tell a good story and highlight Airbnb's service in detail. This strategy makes the case study more authentic and relatable.

Some key points to take away from this case study are:

• Use client's offerings' images rather than just screenshots of your own product or service.
• To begin the case study, it is recommended to include a distinct CTA. For instance, Zendesk presents two alternatives, namely to initiate a trial or seek a solution.

“Influencer Marketing” by Trend and WarbyParker

The case study "Influencer Marketing" by Trend and Warby Parker highlights the potential of influencer content marketing, even when working with a limited budget. 

The “Wearing Warby” campaign involved influencers wearing Warby Parker glasses during their daily activities, providing a glimpse of the brand's products in use. 

This strategy enhanced the brand's relatability with influencers' followers. While not detailing specific tactics, the case study effectively illustrates the impact of third-person case studies in showcasing campaign results.

Key points to take away from this case study are:

• Influencer marketing can be effective even with a limited budget.
• Showcasing products being used in everyday life can make a brand more approachable and relatable.
• Third-person case studies can be useful in highlighting the success of a campaign.

Marketing Case Study Template

Marketing Case Study Example

Now that you have read multiple case study examples, hop on to our tips.

Tips to Write a Good Case Study

Here are some note-worthy tips to craft a winning case study 

• Define the purpose of the case study This will help you to focus on the most important aspects of the case. The case study objective helps to ensure that your finished product is concise and to the point.
• Choose a real-life example. One of the best ways to write a successful case study is to choose a real-life example. This will give your readers a chance to see how the concepts apply in a real-world setting.
• Keep it brief. This means that you should only include information that is directly relevant to your topic and avoid adding unnecessary details.
• Use strong evidence. To make your case study convincing, you will need to use strong evidence. This can include statistics, data from research studies, or quotes from experts in the field.
• Edit and proofread your work. Before you submit your case study, be sure to edit and proofread your work carefully. This will help to ensure that there are no errors and that your paper is clear and concise.

There you go!

We’re sure that now you have secrets to writing a great case study at your fingertips! This blog teaches the key guidelines of various case studies with samples. So grab your pen and start crafting a winning case study right away!

Having said that, we do understand that some of you might be having a hard time writing compelling case studies.

But worry not! Our expert case study writing service is here to take all your case-writing blues away! 

With 100% thorough research guaranteed, we can craft an amazing case study within 24 hours!

Besides, if you're pressed for time, simply uttering the words just do my essay for me will get your essay done quickly and flawlessly!

So why delay? Let us help you shine in the eyes of your instructor!

Write Essay Within 60 Seconds!

Dr. Barbara is a highly experienced writer and author who holds a Ph.D. degree in public health from an Ivy League school. She has worked in the medical field for many years, conducting extensive research on various health topics. Her writing has been featured in several top-tier publications.

Struggling With Your Paper?

Get a custom paper written at

With a FREE Turnitin report, and a 100% money-back guarantee

LIMITED TIME ONLY!

Keep reading

OFFER EXPIRES SOON!

Educational resources and simple solutions for your research journey

What is a Case Study in Research? Definition, Methods, and Examples

Case study methodology offers researchers an exciting opportunity to explore intricate phenomena within specific contexts using a wide range of data sources and collection methods. It is highly pertinent in health and social sciences, environmental studies, social work, education, and business studies. Its diverse applications, such as advancing theory, program evaluation, and intervention development, make it an invaluable tool for driving meaningful research and fostering positive change.[ 1]  

Table of Contents

What is a Case Study?  

A case study method involves a detailed examination of a single subject, such as an individual, group, organization, event, or community, to explore and understand complex issues in real-life contexts. By focusing on one specific case, researchers can gain a deep understanding of the factors and dynamics at play, understanding their complex relationships, which might be missed in broader, more quantitative studies.  

When to do a Case Study?  

A case study design is useful when you want to explore a phenomenon in-depth and in its natural context. Here are some examples of when to use a case study :[ 2]  

• Exploratory Research: When you want to explore a new topic or phenomenon, a case study can help you understand the subject deeply. For example , a researcher studying a newly discovered plant species might use a case study to document its characteristics and behavior.  
• Descriptive Research: If you want to describe a complex phenomenon or process, a case study can provide a detailed and comprehensive description. For instance, a case study design   could describe the experiences of a group of individuals living with a rare disease.  
• Explanatory Research: When you want to understand why a particular phenomenon occurs, a case study can help you identify causal relationships. A case study design could investigate the reasons behind the success or failure of a particular business strategy.  
• Theory Building: Case studies can also be used to develop or refine theories. By systematically analyzing a series of cases, researchers can identify patterns and relationships that can contribute to developing new theories or refining existing ones.  
• Critical Instance: Sometimes, a single case can be used to study a rare or unusual phenomenon, but it is important for theoretical or practical reasons. For example , the case of Phineas Gage, a man who survived a severe brain injury, has been widely studied to understand the relationship between the brain and behavior.  
• Comparative Analysis: Case studies can also compare different cases or contexts. A case study example involves comparing the implementation of a particular policy in different countries to understand its effectiveness and identifying best practices.  

How to Create a Case Study – Step by Step  

Step 1: select a case  .

Careful case selection ensures relevance, insight, and meaningful contribution to existing knowledge in your field. Here’s how you can choose a case study design :[ 3]  

• Define Your Objectives: Clarify the purpose of your case study and what you hope to achieve. Do you want to provide new insights, challenge existing theories, propose solutions to a problem, or explore new research directions?  
• Consider Unusual or Outlying Cases: Focus on unusual, neglected, or outlying cases that can provide unique insights.  
• Choose a Representative Case: Alternatively, select a common or representative case to exemplify a particular category, experience, or phenomenon.   
• Avoid Bias: Ensure your selection process is unbiased using random or criteria-based selection.  
• Be Clear and Specific: Clearly define the boundaries of your study design , including the scope, timeframe, and key stakeholders.   
• Ethical Considerations: Consider ethical issues, such as confidentiality and informed consent.  

Step 2: Build a Theoretical Framework  

To ensure your case study has a solid academic foundation, it’s important to build a theoretical framework:   

• Conduct a Literature Review: Identify key concepts and theories relevant to your case study .  
• Establish Connections with Theory: Connect your case study with existing theories in the field.  
• Guide Your Analysis and Interpretation: Use your theoretical framework to guide your analysis, ensuring your findings are grounded in established theories and concepts.   

Step 3: Collect Your Data  

To conduct a comprehensive case study , you can use various research methods. These include interviews, observations, primary and secondary sources analysis, surveys, and a mixed methods approach. The aim is to gather rich and diverse data to enable a detailed analysis of your case study .  

Step 4: Describe and Analyze the Case  

How you report your findings will depend on the type of research you’re conducting. Here are two approaches:   

• Structured Approach: Follows a scientific paper format, making it easier for readers to follow your argument.  
• Narrative Approach: A more exploratory style aiming to analyze meanings and implications.  

Regardless of the approach you choose, it’s important to include the following elements in your case study :   

• Contextual Details: Provide background information about the case, including relevant historical, cultural, and social factors that may have influenced the outcome.  
• Literature and Theory: Connect your case study to existing literature and theory in the field. Discuss how your findings contribute to or challenge existing knowledge.  
• Wider Patterns or Debates: Consider how your case study fits into wider patterns or debates within the field. Discuss any implications your findings may have for future research or practice.  

What Are the Benefits of a Case Study   

Case studies offer a range of benefits , making them a powerful tool in research.  

1. In-Depth Analysis  

• Comprehensive Understanding: Case studies allow researchers to thoroughly explore a subject, understanding the complexities and nuances involved.  
• Rich Data: They offer rich qualitative and sometimes quantitative data, capturing the intricacies of real-life contexts.  

2. Contextual Insight  

• Real-World Application: Case studies provide insights into real-world applications, making the findings highly relevant and practical.  
• Context-Specific: They highlight how various factors interact within a specific context, offering a detailed picture of the situation.  

3. Flexibility  

• Methodological Diversity: Case studies can use various data collection methods, including interviews, observations, document analysis, and surveys.  
• Adaptability: Researchers can adapt the case study approach to fit the specific needs and circumstances of the research.  

4. Practical Solutions  

• Actionable Insights: The detailed findings from case studies can inform practical solutions and recommendations for practitioners and policymakers.  
• Problem-Solving: They help understand the root causes of problems and devise effective strategies to address them.  

5. Unique Cases  

• Rare Phenomena: Case studies are particularly valuable for studying rare or unique cases that other research methods may not capture.  
• Detailed Documentation: They document and preserve detailed information about specific instances that might otherwise be overlooked.  

What Are the Limitations of a Case Study   

While case studies offer valuable insights and a detailed understanding of complex issues, they have several limitations .  

1. Limited Generalizability  

• Specific Context: Case studies often focus on a single case or a small number of cases, which may limit the generalization of findings to broader populations or different contexts.  
• Unique Situations: The unique characteristics of the case may not be representative of other situations, reducing the applicability of the results.  

2. Subjectivity  

• Researcher Bias: The researcher’s perspectives and interpretations can influence the analysis and conclusions, potentially introducing bias.  
• Participant Bias: Participants’ responses and behaviors may be influenced by their awareness of being studied, known as the Hawthorne effect.  

3. Time-Consuming  

• Data Collection and Analysis: Gathering detailed, in-depth data requires significant time and effort, making case studies more time-consuming than other research methods.  
• Longitudinal Studies: If the case study observes changes over time, it can become even more prolonged.  

4. Resource Intensive  

• Financial and Human Resources: Conducting comprehensive case studies may require significant financial investment and human resources, including trained researchers and participant access.  
• Access to Data: Accessing relevant and reliable data sources can be challenging, particularly in sensitive or proprietary contexts.  

5. Replication Difficulties  

• Unique Contexts: A case study’s specific and detailed context makes it difficult to replicate the study exactly, limiting the ability to validate findings through repetition.  
• Variability: Differences in contexts, researchers, and methodologies can lead to variations in findings, complicating efforts to achieve consistent results.  

By acknowledging and addressing these limitations , researchers can enhance the rigor and reliability of their case study findings.  

Key Takeaways  

Case studies are valuable in research because they provide an in-depth, contextual analysis of a single subject, event, or organization. They allow researchers to explore complex issues in real-world settings, capturing detailed qualitative and quantitative data. This method is useful for generating insights, developing theories, and offering practical solutions to problems. They are versatile, applicable in diverse fields such as business, education, and health, and can complement other research methods by providing rich, contextual evidence. However, their findings may have limited generalizability due to the focus on a specific case.  

Frequently Asked Questions  

Q: What is a case study in research?  

A case study in research is an impactful tool for gaining a deep understanding of complex issues within their real-life context. It combines various data collection methods and provides rich, detailed insights that can inform theory development and practical applications.  

Q: What are the advantages of using case studies in research?  

Case studies are a powerful research method, offering advantages such as in-depth analysis, contextual insights, flexibility, rich data, and the ability to handle complex issues. They are particularly valuable for exploring new areas, generating hypotheses, and providing detailed, illustrative examples that can inform theory and practice.  

Q: Can case studies be used in quantitative research?  

While case studies are predominantly associated with qualitative research, they can effectively incorporate quantitative methods to provide a more comprehensive analysis. A mixed-methods approach leverages qualitative and quantitative research strengths, offering a powerful tool for exploring complex issues in a real-world context. For example , a new medical treatment case study can incorporate quantitative clinical outcomes (e.g., patient recovery rates and dosage levels) along with qualitative patient interviews.  

Q: What are the key components of a case study?  

A case study typically includes several key components:   

• Introductio n, which provides an overview and sets the context by presenting the problem statement and research objectives;  
• Literature review , which connects the study to existing theories and prior research;  
• Methodology , which details the case study design , data collection methods, and analysis techniques;   
• Findings , which present the data and results, including descriptions, patterns, and themes;   
• Discussion and conclusion , which interpret the findings, discuss their implications, and offer conclusions, practical applications, limitations, and suggestions for future research.  

Together, these components ensure a comprehensive, systematic, and insightful exploration of the case.  

References  

• de Vries, K. (2020). Case study methodology. In  Critical qualitative health research  (pp. 41-52). Routledge.  
• Fidel, R. (1984). The case study method: A case study.  Library and Information Science Research ,  6 (3), 273-288.  
• Thomas, G. (2021). How to do your case study.  How to do your case study , 1-320.  

Editage All Access is a subscription-based platform that unifies the best AI tools and services designed to speed up, simplify, and streamline every step of a researcher’s journey. The Editage All Access Pack is a one-of-a-kind subscription that unlocks full access to an AI writing assistant, literature recommender, journal finder, scientific illustration tool, and exclusive discounts on professional publication services from Editage.  

Based on 22+ years of experience in academia, Editage All Access empowers researchers to put their best research forward and move closer to success. Explore our top AI Tools pack, AI Tools + Publication Services pack, or Build Your Own Plan. Find everything a researcher needs to succeed, all in one place –  Get All Access now starting at just $14 a month !    

Related Posts

Paperpal Review: Key Features, Pricing Plans, and How-to-Use

How to Structure a Dissertation? 

• All Headlines

Top 40 Most Popular Case Studies of 2017

We generated a list of the 40 most popular Yale School of Management case studies in 2017 by combining data from our publishers, Google analytics, and other measures of interest and adoption. In compiling the list, we gave additional weight to usage outside Yale

We generated a list of the 40 most popular Yale School of Management case studies in 2017 by combining data from our publishers, Google analytics, and other measures of interest and adoption. In compiling the list, we gave additional weight to usage outside Yale.

Case topics represented on the list vary widely, but a number are drawn from the case team’s focus on healthcare, asset management, and sustainability. The cases also draw on Yale’s continued emphasis on corporate governance, ethics, and the role of business in state and society. Of note, nearly half of the most popular cases feature a woman as either the main protagonist or, in the case of raw cases where multiple characters take the place of a single protagonist, a major leader within the focal organization. While nearly a fourth of the cases were written in the past year, some of the most popular, including Cadbury and Design at Mayo, date from the early years of our program over a decade ago. Nearly two-thirds of the most popular cases were “raw” cases - Yale’s novel, web-based template which allows for a combination of text, documents, spreadsheets, and videos in a single case website.

Read on to learn more about the top 10 most popular cases followed by a complete list of the top 40 cases of 2017.  A selection of the top 40 cases are available for purchase through our online store . 

#1 - Coffee 2016

Faculty Supervision: Todd Cort

Coffee 2016 asks students to consider the coffee supply chain and generate ideas for what can be done to equalize returns across various stakeholders. The case draws a parallel between coffee and wine. Both beverages encourage connoisseurship, but only wine growers reap a premium for their efforts to ensure quality.  The case describes the history of coffee production across the world, the rise of the “third wave” of coffee consumption in the developed world, the efforts of the Illy Company to help coffee growers, and the differences between “fair” trade and direct trade. Faculty have found the case provides a wide canvas to discuss supply chain issues, examine marketing practices, and encourage creative solutions to business problems. 

#2 - AXA: Creating New Corporate Responsibility Metrics

Faculty Supervision: Todd Cort and David Bach

The case describes AXA’s corporate responsibility (CR) function. The company, a global leader in insurance and asset management, had distinguished itself in CR since formally establishing a CR unit in 2008. As the case opens, AXA’s CR unit is being moved from the marketing function to the strategy group occasioning a thorough review as to how CR should fit into AXA’s operations and strategy. Students are asked to identify CR issues of particular concern to the company, examine how addressing these issues would add value to the company, and then create metrics that would capture a business unit’s success or failure in addressing the concerns.

#3 - IBM Corporate Service Corps

Faculty Supervision: David Bach in cooperation with University of Ghana Business School and EGADE

The case considers IBM’s Corporate Service Corps (CSC), a program that had become the largest pro bono consulting program in the world. The case describes the program’s triple-benefit: leadership training to the brightest young IBMers, brand recognition for IBM in emerging markets, and community improvement in the areas served by IBM’s host organizations. As the program entered its second decade in 2016, students are asked to consider how the program can be improved. The case allows faculty to lead a discussion about training, marketing in emerging economies, and various ways of providing social benefit. The case highlights the synergies as well as trade-offs between pursuing these triple benefits.

#4 - Cadbury: An Ethical Company Struggles to Insure the Integrity of Its Supply Chain

Faculty Supervision: Ira Millstein

The case describes revelations that the production of cocoa in the Côte d’Ivoire involved child slave labor. These stories hit Cadbury especially hard. Cadbury's culture had been deeply rooted in the religious traditions of the company's founders, and the organization had paid close attention to the welfare of its workers and its sourcing practices. The US Congress was considering legislation that would allow chocolate grown on certified plantations to be labeled “slave labor free,” painting the rest of the industry in a bad light. Chocolate producers had asked for time to rectify the situation, but the extension they negotiated was running out. Students are asked whether Cadbury should join with the industry to lobby for more time?  What else could Cadbury do to ensure its supply chain was ethically managed?

#5 - 360 State Real Options

Faculty Supervision: Matthew Spiegel

In 2010 developer Bruce Becker (SOM ‘85) completed 360 State Street, a major new construction project in downtown New Haven. Just west of the apartment building, a 6,000-square-foot pocket of land from the original parcel remained undeveloped. Becker had a number of alternatives to consider in regards to the site. He also had no obligation to build. He could bide his time. But Becker worried about losing out on rents should he wait too long. Students are asked under what set of circumstances and at what time would it be most advantageous to proceed?

#6 - Design at Mayo

Faculty Supervision: Rodrigo Canales and William Drentell

The case describes how the Mayo Clinic, one of the most prominent hospitals in the world, engaged designers and built a research institute, the Center for Innovation (CFI), to study the processes of healthcare provision. The case documents the many incremental innovations the designers were able to implement and the way designers learned to interact with physicians and vice-versa.

In 2010 there were questions about how the CFI would achieve its stated aspiration of “transformational change” in the healthcare field. Students are asked what would a major change in health care delivery look like? How should the CFI's impact be measured? Were the center's structure and processes appropriate for transformational change? Faculty have found this a great case to discuss institutional obstacles to innovation, the importance of culture in organizational change efforts, and the differences in types of innovation.

This case is freely available to the public.

#7 - Ant Financial

Faculty Supervision: K. Sudhir in cooperation with Renmin University of China School of Business

In 2015, Ant Financial’s MYbank (an offshoot of Jack Ma’s Alibaba company) was looking to extend services to rural areas in China by providing small loans to farmers. Microloans have always been costly for financial institutions to offer to the unbanked (though important in development) but MYbank believed that fintech innovations such as using the internet to communicate with loan applicants and judge their credit worthiness would make the program sustainable. Students are asked whether MYbank could operate the program at scale? Would its big data and technical analysis provide an accurate measure of credit risk for loans to small customers? Could MYbank rely on its new credit-scoring system to reduce operating costs to make the program sustainable?

#8 - Business Leadership in South Africa’s 1994 Reforms

Faculty Supervision: Ian Shapiro

This case examines the role of business in South Africa's historic transition away from apartheid to popular sovereignty. The case provides a previously untold oral history of this key moment in world history, presenting extensive video interviews with business leaders who spearheaded behind-the-scenes negotiations between the African National Congress and the government. Faculty teaching the case have used the material to push students to consider business’s role in a divided society and ask: What factors led business leaders to act to push the country's future away from isolation toward a "high road" of participating in an increasingly globalized economy? What techniques and narratives did they use to keep the two sides talking and resolve the political impasse? And, if business leadership played an important role in the events in South Africa, could they take a similar role elsewhere?

#9 - Shake Shack IPO

Faculty Supervision: Jake Thomas and Geert Rouwenhorst

From an art project in a New York City park, Shake Shack developed a devoted fan base that greeted new Shake Shack locations with cheers and long lines. When Shake Shack went public on January 30, 2015, investors displayed a similar enthusiasm. Opening day investors bid up the $21 per share offering price by 118% to reach $45.90 at closing bell. By the end of May, investors were paying $92.86 per share. Students are asked if this price represented a realistic valuation of the enterprise and if not, what was Shake Shack truly worth? The case provides extensive information on Shake Shack’s marketing, competitors, operations and financials, allowing instructors to weave a wide variety of factors into a valuation of the company.

#10 - Searching for a Search Fund Structure

Faculty Supervision: AJ Wasserstein

This case considers how young entrepreneurs structure search funds to find businesses to take over. The case describes an MBA student who meets with a number of successful search fund entrepreneurs who have taken alternative routes to raising funds. The case considers the issues of partnering, soliciting funds vs. self-funding a search, and joining an incubator. The case provides a platform from which to discuss the pros and cons of various search fund structures.

40 Most Popular Case Studies of 2017

Click on the case title to learn more about the dilemma. A selection of our most popular cases are available for purchase via our online store .

Related Stories

Top 40 Case Studies of 2022-23

Top 40 Most Popular Case Studies of 2021

Top 40 Most Popular Case Studies of 2020

An official website of the United States government

Official websites use .gov A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS A lock ( Lock Locked padlock icon ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

• Publications
• Account settings
• Advanced Search
• Journal List

Isotretinoin, depression and suicide: a review of the evidence

Parker magin , fracgp, dimity pond , phd, fracgp, wayne smith , phd.

• Author information
• Article notes
• Copyright and License information

Address for correspondence Dr Parker Magin; Discipline of General Practice, Newbolds Building, University of Newcastle, University Drive, Callaghan 2308 New South Wales, Australia. E-mail: [email protected]

Received 2004 Mar 18; Revised 2004 May 28; Accepted 2004 Jul 1.

There is currently considerable controversy regarding a proposed causal relationship between the use of isotretinoin and depression and suicide. A search was made of the MEDLINE, EMBASE and PsychINFO databases using the search terms ‘isotretinoin’, ‘depression’ and ‘suicide’. Despite numerous case reports linking isotretinoin to depression, suicidal ideation and suicide, there is, as yet, no clear proof of an association. While isotretinoin, used to treat acne vulgaris, has not been demonstrated to be associated with depression or suicide, the possibility of a relatively rare idiosyncratic adverse effect remains. GPs have a role in the clinical application of these findings.

Keywords: acne vulgaris, depression, isotretinoin, suicide

INTRODUCTION

Isotretinoin is an efficacious and widely-used therapy for severe acne. 1 , 2 Its introduction has been hailed as ‘an incredible triumph … in the treatment of acne vulgaris’. 3 But it is recognised as having a wide range of adverse effects. The most notable of these is teratogenicity, 3 but mucocutaneous, ophthalmic, and musculoskeletal effects and effects on plasma lipids and liver function tests are also acknowledged side effects. 1 , 2 , 4 The relationship of isotretinoin to depression and suicide is more controversial and will be discussed in this article.

Searches were made of the MEDLINE, EMBASE and PsychINFO databases. Search terms used were isotretinoin, depression and suicide. The search was confined to English language articles. Reference lists of identified articles were examined for further relevant studies. There were no pre-specified quality criteria for study inclusion. Given the relative paucity of methodologically rigorous studies in this area, and the considerable influence on current practice of case reports, no evidence was excluded on methodological grounds.

Warnings regarding isotretinoin, depression and suicide

In 1998 the US Food and Drug Administration (FDA) issued a warning to physicians regarding a possible association with depression, psychosis, suicidal ideation and suicide. 5 , 6 The FDA recommends the use of signed informed consent forms and a printed patient medication guide for patients prescribed isotretinoin. 7 , 8 The FDA's 1998 warning was noted in the Lancet as being in response to a ‘possible connection … although there is no evidence’. 9

What is the evidence for an association?

Case reports.

A number of case reports and case series linking isotretinoin to depression or suicide have appeared in the medical and psychological literature since 1982. 10 - 19 Between 1982 and 2000 the FDA has received reports of 394 cases of depression, and 37 suicides occurring in patients exposed to isotretinoin. 7 , 20 It is the fifth most common drug reported to the US Adverse Event Reporting System (AERS) in association with depression, and the tenth most common (and the only non-psychotropic drug) in suicide reports. 7 In Canada, psychiatric adverse effects in patients taking isotretinoin have been reported to Health Canada 21 — 56 events between 1983 and 2003. 22 Forty-two psychiatric reactions were reported to the British Medicines Control Agency between 1982 and 1998, 23 including a small number of suicides. 24 In Australia from 1995 to 1998 the Adverse Drug Reactions Advisory Committee received 12 reports of depression in patients taking isotretinoin. 25 Two cases were described as severe, in four there were psychotic features, in three there was suicidal ideation and there were three suicide attempts (with one completed suicide).

In a number of these case reports, including 25 documented by the FDA, 7 , 20 cessation of the drug has been associated with resolution of the mood disturbance and reinstitution of treatment has been followed by recurrence of depression.

But pitfalls inherent in making inferences of causality from case reports or case series are illustrated by the case reported by Kovacs and Mallory. 26 They describe a 17-year-old Korean boy who developed mood and behaviour changes while taking isotretinoin. Symptoms resolved with isotretinoin withdrawal, but re-emerged with rechallenge, and the boy's psychological morbidity was attributed to isotretinoin. It later emerged that the boy's symptoms also coincided with periods of recreational LSD and cannabis use.

Secondary analyses of large data sets

Jick et al 27 analysed data from the Canadian Health Database and the UK General Practice Research Database and found no increase in relative risk of incident depression, psychosis, suicide or attempted suicide in users of isotretinoin over users of antibiotics for acne. Similarly, there was no increase in relative risk of these outcomes for prior treatment with isotretinoin versus post-treatment. This was an industry-sponsored study and its methodology has been criticised. 28 Specifically, possible underascertainment of psychiatric disorder and suicide, the lack of a non-acne control group, a lack of power for detecting differences in suicide rates, and lack of consideration of acne severity or of isotretinoin dose and duration were claimed to be methodological shortcomings. 28

Hersom et al 29 performed a retrospective prescription sequence symmetry analysis of isotretinoin and antidepressant pharmacotherapy using a large US database (examining which drug was prescribed first in patients prescribed both isotretinoin and an antidepressant) and demonstrated no support for an association between the use of isotretinoin and the onset of depression.

Wyskowski et al observed that a statistical data mining analysis of all adverse events and drug combinations in the AERS database had calculated that six reports of suicide were expected for isotretinoin compared with the 36 suicides actually reported 7 ( Table 1 ).

Studies examining isotretinoin, depression and suicide.

An extended version of this table can be found at http://www.rcgp.org.uk/journal/index.asp .

Assessments of depression as an adverse event in clinical trials and follow-up of treatment with isotretinoin

Prospective Canadian 30 and US 31 studies found an incidence of depression in patients during a course of isotretinoin therapy of 4% and 11%, respectively. However, these trials were uncontrolled and depression was self-reported in response to a questionnaire item. There was no objective measure of depression. The study of Scheinman et al 12 has been quoted as finding an 1% incidence of depression in isotretinoin therapy, 26 but did not specifically examine for depression or other psychiatric morbidity. It describes seven patients who spontaneously reported depressive symptoms during clinical trials of isotretinoin, and is best considered a case series (and is cited as such above). A British study 32 elicited no long-term side effects of isotretinoin in 88 patients up to 10 years post-therapy, but the authors do not seem to have specifically enquired about depression or other psychiatric effects. Similarly, Goulden et al 33 reported on 720 patients who had received one or more courses of isotretinoin and were followed up every 4–6 months for 2–12 years. They found only three cases of depression occurring in this population (all occurring in patients with dysmorphophobia and mild acne). But this was an uncontrolled study and, while adverse effects of the medication were enquired about generally, depression and suicidal ideation were not among the side effects specifically asked about. A further study of adverse effects in 466 isotretinoin recipients in the US 34 recorded no instances of depression or other psychiatric effects, but this was a study of data abstracted from clinical notes for self-reported side effects rather than an examination of psychiatric morbidity.

McLane 35 reports incidence of ‘psychiatric disorders’ as adverse events of isotretinoin therapy as being 0% and 0.3% in industry-sponsored trials with 69 and 300 subjects, respectively. But these trials were uncontrolled, and the means of ascertainment of psychiatric disorder is not specified ( Table 1 ).

Improvement in depression in clinical trials with isotretinoin

A number of studies have demonstrated an improvement in depression scores in patients with acne during and/or after treatment with isotretinoin. 36 - 38 Interpretation of these treatment studies with regard to the direction of causality in the association between acne and depression is limited by them being uncontrolled and/or not correlating changes in depression with changes in acne severity.

Further considerations

A plausible biological mechanism underlying the proposed causative relationship — the effect of retinoids on brain dopamine systems 39 , 40 — has been suggested, although this remains speculative. Etretinate, another retinoid used as therapy in cutaneous disease, has been linked in case reports with depression. 41 Additionally, it has been suggested that hypervitaminosis A is associated with psychiatric symptoms including depression, and hypervitaminosis A syndrome has been proposed as a paradigm of retinoid side effects. 17 , 42 Other ‘neuropsychological’ adverse effects — irritability, emotional lability, amnesia, abnormal thinking, headache, fatigue, lethargy, pseudotumour cerebri, incoordination and sustained dreaming — have been reported with use of isotretinoin. 1 , 2 , 21 , 30 , 31 , 34 , 35 , 43

How this fits in

There is currently a controversy regarding the risk of depression and suicide in treatment with isotretinoin. The controversy, thus far, has largely by-passed the general practice audience, but has significant implications for general practice approaches to the management of acne vulgaris.

It is likely that the surveillance systems cited above underestimate the true incidence of adverse effects. However, the background incidence of depression, suicide attempts and completed suicide in adolescents, and the number of patients who have used the drug must also be considered when interpreting the significance of case reports and adverse event monitoring in isotretinoin therapy. Over 8 million patients had used isotretinoin worldwide by 1998. 5 The 12-month prevalence of major depression in the US has been found to be 10.3% and of dysthymia to be 2.5% in a major study, 44 although prevalence has been somewhat lower in some studies. 45 Thirty–day prevalence among adolescents and young adults of major depression was 5.8% and minor depression was 2.1%. 46 Depression is more common in the age group affected by acne than in the general population. 44 , 45 , 47 In 1994, the US suicide rate was 12 per 100 000 population. 48 Reported lifetime suicidal ideation in the US is 13.5% and lifetime prevalence of suicide attempt is 4.6%. 49 In prospective studies of US 50 and Norwegian 51 high school students, the 12-month incidence of suicide attempt was 1.7% and 1.3 %, respectively.

It has also been suggested that many of the reported depressive adverse effects in isotretinoin therapy represent depressive or mood symptoms rather than major depression or other clinical depression syndromes. 52 In this context it should be noted that an Australian population-based study of high school students has shown 19% of students without clinical depression to have depressed mood. 53 Significantly, while in some of the case reports and study findings of depression cited in this review the diagnosis was confirmed by psychiatric opinion, 13 , 14 , 17 , 18 others seemed not to be, 10 , 11 , 19 , 30 , 31 while in one case series some diagnoses were psychiatrist-confirmed and some were not. 12

Prospective, controlled trials to examine the relationship might seem to be apposite. But recruitment of adequate numbers of subjects into studies powered to detect an increase in suicide would be a daunting prospect. Controlled trials of depression and suicidal ideation may also be problematic — it has been suggested that, given the superior efficacy of isotretinoin and the propensity for severe acne to cause permanent scarring, a randomised trial of isotretinoin compared with a less efficacious control in severe acne would be unethical. 32 In this situation, large case-control studies would be welcome.

The context of the debate

While acne may have been, in some quarters, considered a trivial complaint, there is convincing evidence that this is not so. Case reports have suggested depression as a sequela of acne. 54 Studies have suggested acne is associated with greater mental health impairment than asthma, epilepsy, diabetes, back pain or arthritis. 55 Acne has been associated with depression, 56 - 59 suicidal ideation 56 and (in a case series) with suicide, 60 along with a number of other psychological problems — anxiety, self-consciousness, emotional difficulties and embarrassment. 38 , 61 - 66 Studies of treatment with isotretinoin show improvements in depression scores following treatment (as above). The balance of evidence suggests that acne is associated with considerable psychological morbidity, possibly including depression, and that acne is more likely to cause psychological morbidity than to be caused by it.

In fact, the presence of psychological distress in a patient with acne has been proposed as an indication for a more aggressive approach to acne treatment, including the use of isotretinoin. 67

Interpretation of the available evidence and the clinical context

The evidence in this area is incomplete. The incidence of depression and suicide during isotretinoin therapy may be no greater than the background incidence. A causal relationship between isotretinioin and psychiatric morbidity, including depression and suicide, has not been demonstrated. In fact, there is evidence that acne itself is associated with psychiatric morbidity and that isotretinoin may attenuate the effect of acne on this psychiatric morbidity. Nevertheless, major depression and suicidal ideation occurring as an idiosyncratic reaction to isotretinoin, as suggested by case reports, remains a possibility — although, if so, this would seem to be a relatively rare occurrence.

Relevance to general practice

In Australia and the UK isotretinoin is not prescribed by GPs. 32 , 68 In the US, many family physicians choose not to prescribe it. 69 Referral of patients with acne who would benefit from isotretinoin is the responsibility of the GP, and, therefore, the debate about isotretinoin and depression and suicide in the media, 70 , 71 is of vital interest. GPs are in a position not only to make suggestions or recommendations to patients regarding referral for consideration of isotretinoin treatment, but also to ensure patient decisions are based on a realistic understanding of the benefits and risks of therapy.

It would seem prudent to carefully monitor patients undergoing treatment with isotretinoin for evidence of depression or suicidal ideation. GPs are likely to be better equipped than dermatologists to do so, 72 - 74 and to further manage, or refer for specialist psychiatric care, any emergent psychiatric symptoms or psychological morbidity. A close partnership between dermatologist and GP on a ‘shared-care’ basis is likely to be optimal in this situation.

Conclusions

Consideration of the limited data available would suggest that the incidence of depression and suicide during isotretinoin therapy may be no greater than the background incidence. A causal relationship has not been demonstrated. The occurrence of an idiosyncratic reaction to isotretinoin producing major depression and suicidal ideation, as suggested by case studies, remains a possibility — although, if so, this would seem to be a relatively rare occurrence. Given the evidence suggesting that isotretinoin treatment may attenuate psychiatric associations of acne, and given the evidence that acne is often not a trivial complaint, withholding therapy because of concerns regarding depression or potential for suicide is not justified. Nevertheless, there are grounds for carefully monitoring patients undergoing treatment with isotretinoin for the emergence of depressive and suicidal ideation. Ideally, the patient's GP, as well as their dermatologist, should be involved in this surveillance.

Supplementary Material

Funding body and reference number.

This article was written with support from a NHMRC post-graduate medical scholarship and a NSW Primary Health Care Research Bursary

Competing interests

• 1. Brecher AR, Orlow SJ. Oral retinoid therapy for dermatological conditions in children and adolescents. J Am Acad Dermatol. 2003;49:171–182. doi: 10.1067/s0190-9622(03)01564-0. [ DOI ] [ PubMed ] [ Google Scholar ]
• 2. Ellis CN, Krach KJ. Uses and complications of isotretinoin therapy. J Am Acad Dermatol. 2001;45(5):S150–S157. doi: 10.1067/mjd.2001.113717. [ DOI ] [ PubMed ] [ Google Scholar ]
• 3. Lowenstein EJ. Isotretinoin made S.M.A.R.T. and simple. Cutis. 2002;70(2):115–120. [ PubMed ] [ Google Scholar ]
• 4. Hanson N, Leachman S. Safety issues in isotretinoin therapy. Semin Cutan Med Surg. 2001;20(3):166–183. doi: 10.1053/sder.2001.28209. [ DOI ] [ PubMed ] [ Google Scholar ]
• 5. Josefson D. Acne drug is linked to severe depression. BMJ. 1998;316(7133):723. doi: 10.1136/bmj.316.7133.723a. [ DOI ] [ PubMed ] [ Google Scholar ]
• 6. Lamberg L. Acne drug depression warnings highlight need for expert care. JAMA. 1998;279(14):1057. [ PubMed ] [ Google Scholar ]
• 7. Wysowski D, Pitts M, Beitz J. An analysis of reports of depression and suicide in patients treated with isotretinoin. J Am Acad Dermatol. 2001;45:515–519. doi: 10.1067/mjd.2001.117730. [ DOI ] [ PubMed ] [ Google Scholar ]
• 8. Schwetz BA. New measures to manage risks associated with accutane. JAMA. 2001;285(5):1146. [ Google Scholar ]
• 9. Ault A. Isotretinoin use may be linked with depression. Lancet. 1998;351(9104):730. [ Google Scholar ]
• 10. Hazen PG, Carney JF, Walker AE, Stewart JJ. Depression — a side effect of 13-cis-retinoic acid therapy. J Am Acad Dermatol. 1983;9(2):278–279. doi: 10.1016/s0190-9622(83)80154-6. [ DOI ] [ PubMed ] [ Google Scholar ]
• 11. Meyskens FL. Short clinical reports. J Am Acad Dermatol. 1982;6(4[2]):732. [ PubMed ] [ Google Scholar ]
• 12. Scheinman PL, Peck GL, Rubinow DR, et al. Acute depression from isotretinoin [comment] J Am Acad Dermatol. 1990;22(6 Pt 1):1112–1114. doi: 10.1016/s0190-9622(08)81018-3. [ DOI ] [ PubMed ] [ Google Scholar ]
• 13. Gatti S, Serri F. Acute depression from isotretinoin [comment] J Am Acad Dermatol. 1991;25(1 Pt 1):132. doi: 10.1016/s0190-9622(08)80509-9. [ DOI ] [ PubMed ] [ Google Scholar ]
• 14. Byrne A, Hnatko G. Depression associated with isotretinoin therapy. Can J Psychiatry. 1995;40(9):567. doi: 10.1177/070674379504000915. [ DOI ] [ PubMed ] [ Google Scholar ]
• 15. Lindemayr H. Isotretinoin intoxication in attempted suicide. Acta Derm Venereol. 1986;66(5):452–453. [ PubMed ] [ Google Scholar ]
• 16. James M. Isotretinoin for severe acne [comment] Lancet. 1996;347(9017):1749–1750. doi: 10.1016/s0140-6736(96)90814-4. [ DOI ] [ PubMed ] [ Google Scholar ]
• 17. Ng CH, Tam MM, Hook SJ. Acne, isotretinoin treatment and acute depression. World J Biol Psychiatry. 2001;2(3):159–161. doi: 10.3109/15622970109026803. [ DOI ] [ PubMed ] [ Google Scholar ]
• 18. Byrne A, Costello M, Greene E, Zibin T. Isotretinoin therapy and depression — Evidence for an association. Ir J Psychol Med. 1998;15(2):58–60. [ Google Scholar ]
• 19. Duke EE, Guenther L. Psychiatric reactions to te retinoids. Canadian Journal of Dermatology. 1993;5(4):467. [ Google Scholar ]
• 20. Wysowski D, Pitts M, Beitz J. Depression and suicide in patients treated with isotretinoin. New Engl J Med. 2001;344(6):460–461. doi: 10.1056/NEJM200102083440616. [ DOI ] [ PubMed ] [ Google Scholar ]
• 21. Wray CM. Isotretinoin: depression. Canadian Adverse Drug Reaction Newsletter. 1999;9(1):1. [ Google Scholar ]
• 22. Wooltorton E. Accutane (isotretinoin) and psychiatric adverse effects. CMAJ. 2003;168(1):66. [ PMC free article ] [ PubMed ] [ Google Scholar ]
• 23. Medicines Control Agency. In focus: isotretinoin. Current Problems in Pharmacovigilence. 1998;24:2. [ Google Scholar ]
• 24. Chu A, Cunliffe WJ. The inter-relationship between isotretinoin/acne and depression. J Eur Acad Dermatol Venereol. 1999;12(3):263. doi: 10.1111/j.1468-3083.1999.tb01042.x. [ DOI ] [ PubMed ] [ Google Scholar ]
• 25. Adverse Drug Reactions Advisory Committee. Depression and isotretinoin. Australian Adverse Drug Reaction Bulletin. 1998;17(3):11. [ Google Scholar ]
• 26. Kovacs SO, Mallory SB. Mood changes associated with isotretinoin and substance abuse. Pediatr Dermatol. 1996;13(4):350. doi: 10.1111/j.1525-1470.1996.tb01255.x. [ DOI ] [ PubMed ] [ Google Scholar ]
• 27. Jick S, Kremers H, Vasilakis-Scaramozza C. Isotretinoin use and risk of depression, psychotic symptoms, suicide and attempted suicide. Arch Dermatol. 2000;136(10):1231. doi: 10.1001/archderm.136.10.1231. [ DOI ] [ PubMed ] [ Google Scholar ]
• 28. Wysowski D, Beitz J. Methodological limitations of the study ‘isotretinoin use and risk of depression psychotic symptoms, suicide and attempted suicide’. Arch Dermatol. 2001;137(8):1102. [ PubMed ] [ Google Scholar ]
• 29. Hersom K, Neary MP, Levaux HP, Klaskala W, Strauss JS. Isotretinoin and antidepressant pharmacotherapy: a prescription sequence symmetry analysis. J Am Acad Dermatol. 2003;49(3):424–32. doi: 10.1067/s0190-9622(03)02087-5. [ DOI ] [ PubMed ] [ Google Scholar ]
• 30. Hull PR, Demkiw-Bartel C. Isotretinoin use in acne: prospective evaluation of adverse events. J Cutan Med Surg. 2000;4(2):66–70. doi: 10.1177/120347540000400205. [ DOI ] [ PubMed ] [ Google Scholar ]
• 31. Bruno NP, Beacham BE, Burnett JW. Adverse effects of isotretinoin therapy. Cutis. 1984;33(5):484–486. 489. [ PubMed ] [ Google Scholar ]
• 32. Layton A, Knaggs H, Taylor J, Cunliffe WJ. Isotretinoin for acne vulgaris — ten years later: a safe and successful treatment. Br J Dermatol. 1993;129:292–296. doi: 10.1111/j.1365-2133.1993.tb11849.x. [ DOI ] [ PubMed ] [ Google Scholar ]
• 33. Goulden V, Layton AM, Cunliffe WJ. Long-term safety of isotretinoin as a treatment for acne vulgaris. Br J Dermatol. 1994;131(3):360–363. doi: 10.1111/j.1365-2133.1994.tb08524.x. [ DOI ] [ PubMed ] [ Google Scholar ]
• 34. McElwee NE, Schumacher MC, Johnson SC, et al. An observational study of isotretinoin recipients treated for acne in a health maintenance organization. Arch Dermatol. 1991;127(3):341–346. [ PubMed ] [ Google Scholar ]
• 35. McLane J. Analysis of common side effects of isotretinoin. J Am Acad Dermatol. 2001;45(5):S188–S194. doi: 10.1067/mjd.2001.113719. [ DOI ] [ PubMed ] [ Google Scholar ]
• 36. Strauss JS, Leyden JJ, Lucky AW, et al. Safety of a new micronized formulation of isotretinoin in patients with severe recalcitrant nodular acne: A randomized trial comparing micronized isotretinoin with standard isotretinoin [comment] J Am Acad Dermatol. 2001;45(2):196–207. doi: 10.1067/mjd.2001.115966. [ DOI ] [ PubMed ] [ Google Scholar ]
• 37. Rubinow DR, Peck GL, Squillace KM, Gantt GG. Reduced anxiety and depression in cystic acne patients after successful treatment with oral isotretinoin. J Am Acad Dermatol. 1987;17(1):25–32. doi: 10.1016/s0190-9622(87)70166-2. [ DOI ] [ PubMed ] [ Google Scholar ]
• 38. Schulpis K, Georgala S, Papakonstantinou ED, Michas T. Psychological and sympatho-adrenal status in patients with cystic acne. J Eur Acad Dermatol Venereol. 1999;13(1):24–27. [ PubMed ] [ Google Scholar ]
• 39. McCaffery P, Drager UC. High levels of a retinoic acid-generating dehydrogenase in the meso-telencephalic dopamine system. Proc Natl Acad Sci U S A. 1994;91(16):7772–7776. doi: 10.1073/pnas.91.16.7772. [ DOI ] [ PMC free article ] [ PubMed ] [ Google Scholar ]
• 40. Samad TA, Krezel W, Chambon P, Borrelli E. Regulation of dopaminergic pathways by retinoids: activation of the D2 receptor promoter by members of the retinoic acid receptor-retinoid X receptor family. Proc Natl Acad Sci USA. 1997;94(26):14349–14354. doi: 10.1073/pnas.94.26.14349. [ DOI ] [ PMC free article ] [ PubMed ] [ Google Scholar ]
• 41. Henderson CA, Highet AS. Depression induced by etretinate. BMJ. 1989;298(6678):964. doi: 10.1136/bmj.298.6678.964. [ DOI ] [ PMC free article ] [ PubMed ] [ Google Scholar ]
• 42. Silverman AK, Ellis CN, Voorhees JJ. Hypervitaminosis A syndrome: a paradigm of retinoid side effects. J Am Acad Dermatol. 1987;16(5 Pt 1):1027–1039. doi: 10.1016/s0190-9622(87)70133-9. [ DOI ] [ PubMed ] [ Google Scholar ]
• 43. Gupta MA, Gupta AK. Isotretinoin use and reports of sustained dreaming. Br J Dermatol. 2001;144(4):919–920. doi: 10.1046/j.1365-2133.2001.04171.x. [ DOI ] [ PubMed ] [ Google Scholar ]
• 44. Kessler RC, McGonagle KA, Zhao S, et al. Lifetime and 12-month prevalence of DSM-III-R psychiatric disorders in the United States. Results from the National Comorbidity Survey. Arch Gen Psychiatry. 1994;51(1):8–19. doi: 10.1001/archpsyc.1994.03950010008002. [ DOI ] [ PubMed ] [ Google Scholar ]
• 45. Kessler RC, Berglund P, Demler O, et al. The epidemiology of major depressive disorder: results from the National Comorbidity Survey Replication (NCS-R) [comment] JAMA. 2003;289(23):3095–3105. doi: 10.1001/jama.289.23.3095. [ DOI ] [ PubMed ] [ Google Scholar ]
• 46. Kessler RC, Walters EE. Epidemiology of DSM-III-R major depression and minor depression among adolescents and young adults in the National Comorbidity Survey. Depress Anxiety. 1998;7(1):3–14. doi: 10.1002/(sici)1520-6394(1998)7:1<3::aid-da2>3.0.co;2-f. [ DOI ] [ PubMed ] [ Google Scholar ]
• 47. Henderson S, Andrews G, Hall W. Australia's mental health: an overview of the general population survey. Aust N Z J Psychiatry. 2000;34(2):197–205. doi: 10.1080/j.1440-1614.2000.00686.x. [ DOI ] [ PubMed ] [ Google Scholar ]
• 48. Anonymous. From the Centers for Disease Control and Prevention. Regional variations in suicide rates — United States, 1990–1994. JAMA. 1997;278(12):974–975. [ PubMed ] [ Google Scholar ]
• 49. Kessler RC, Borges G, Walters EE. Prevalence of and risk factors for lifetime suicide attempts in the National Comorbidity Survey. Arch Gen Psychiatry. 1999;56(7):617–626. doi: 10.1001/archpsyc.56.7.617. [ DOI ] [ PubMed ] [ Google Scholar ]
• 50. Lewinsohn PM, Rohde P, Seeley JR. Psychosocial risk factors for future adolescent suicide attempts. J Consult Clin Psychol. 1994;62(2):297–305. doi: 10.1037//0022-006x.62.2.297. [ DOI ] [ PubMed ] [ Google Scholar ]
• 51. Wichstrom L. Predictors of adolescent suicide attempts: a nationally representative longitudinal study of Norwegian adolescents. J Am Acad Child Adolesc Psychiatry. 2000;39(5):603–610. doi: 10.1097/00004583-200005000-00014. [ DOI ] [ PubMed ] [ Google Scholar ]
• 52. Jacobs D, Deutsch N, Brewer M. Suicide, depression, and isotretinoin: is there a link? J Am Acad Dermatol. 2001;45:S168–S175. doi: 10.1067/mjd.2001.118233. [ DOI ] [ PubMed ] [ Google Scholar ]
• 53. Patton GC, Coffey C, Posterino M, et al. Adolescent depressive disorder: a population-based study of ICD-10 symptoms. Aust N Z J Psychiatry. 2000;34(5):741–747. doi: 10.1080/j.1440-1614.2000.00825.x. [ DOI ] [ PubMed ] [ Google Scholar ]
• 54. Finlay SE. Physical diseases in university students. BMJ. 1976;2(6047):1312–1314. doi: 10.1136/bmj.2.6047.1312. [ DOI ] [ PMC free article ] [ PubMed ] [ Google Scholar ]
• 55. Mallon E, Newton JN, Klassen A, et al. The quality of life in acne: a comparison with general medical conditions using generic questionnaires. Br J Dermatol. 1999;140(4):672–676. doi: 10.1046/j.1365-2133.1999.02768.x. [ DOI ] [ PubMed ] [ Google Scholar ]
• 56. Gupta MA, Gupta AK. Depression and suicidal ideation in dermatology patients with acne, alopecia areata, atopic dermatitis and psoriasis. Br J Dermatol. 1998;139(5):846–850. doi: 10.1046/j.1365-2133.1998.02511.x. [ DOI ] [ PubMed ] [ Google Scholar ]
• 57. Polenghi MM, Zizak S, Molinari E. Emotions and acne. Dermatology and Psychosomatics. 2002;3:20–25. [ Google Scholar ]
• 58. Koo J. The psychosocial impact of acne: patients' perceptions. J Am Acad Dermatol. 1995;32(5 Pt 3):S26–S30. doi: 10.1016/0190-9622(95)90417-4. [ DOI ] [ PubMed ] [ Google Scholar ]
• 59. Kellett SC, Gawkrodger DJ. The psychological and emotional impact of acne and the effect of treatment with isotretinoin. Br J Dermatol. 1999;140(2):273–282. doi: 10.1046/j.1365-2133.1999.02662.x. [ DOI ] [ PubMed ] [ Google Scholar ]
• 60. Cotterill JA, Cunliffe WJ. Suicide in dermatological patients. Br J Dermatol. 1997;137(2):246–250. doi: 10.1046/j.1365-2133.1997.18131897.x. [ DOI ] [ PubMed ] [ Google Scholar ]
• 61. Wu SF, Kinder BN, Trunnell TN, Fulton JE. Role of anxiety and anger in acne patients: a relationship with the severity of the disorder. J Am Acad Dermatol. 1988;18(2 Pt 1):325–333. doi: 10.1016/s0190-9622(88)70047-x. [ DOI ] [ PubMed ] [ Google Scholar ]
• 62. Grahame V, Dick DC, Morton CM, et al. The psychological correlates of treatment efficacy in acne. Dermatology and Psychosomatics. 2002;3:119–125. [ Google Scholar ]
• 63. Aktan S, Ozmen E, Sanli B. Anxiety, depression, and nature of acne vulgaris in adolescents. Int J Dermatol. 2000;39(5):354–357. doi: 10.1046/j.1365-4362.2000.00907.x. [ DOI ] [ PubMed ] [ Google Scholar ]
• 64. Smithard A, Glazebrook C, Williams HC. Acne prevalence, knowledge about acne and psychological morbidity in mid-adolescence: a community-based study. Br J Dermatol. 2001;145(2):274–279. doi: 10.1046/j.1365-2133.2001.04346.x. [ DOI ] [ PubMed ] [ Google Scholar ]
• 65. Pearl A, Arroll B, Lello J, Birchall NM. The impact of acne: a study of adolescents' attitudes, perception and knowledge. N Z Med J. 1998;111(1070):269–71. [ PubMed ] [ Google Scholar ]
• 66. Krowchuk DP, Stancin T, Keskinen R, et al. The psychosocial effects of acne on adolescents. Pediatr Dermatol. 1991;8(4):332–338. doi: 10.1111/j.1525-1470.1991.tb00945.x. [ DOI ] [ PubMed ] [ Google Scholar ]
• 67. Cooper AJ. Australian Roaccutane Advisory B. Treatment of acne with isotretinoin: recommendations based on Australian experience. Australas J Dermatol. 2003;44(2):97–105. doi: 10.1046/j.1440-0960.2003.00653.x. [ DOI ] [ PubMed ] [ Google Scholar ]
• 68. Writing Group for Therapeutics Guidelines. Dermatology. Therapeutics Guidelines: Dermatology. Melbourne: Therapeutics Guidelines Limited; 1999. [ Google Scholar ]
• 69. Van Durme DJ. Family physicians and accutane [comment] Am Fam Physician. 2000;62(8):1772, 1774, 1777. [ PubMed ] [ Google Scholar ]
• 70. Weinberg JM. Scars: the battle over isotretinoin. Cutis. 2001;68(1):18. [ PubMed ] [ Google Scholar ]
• 71. Duenwald M. Debate on acne drug's safety persists over two decades. The New York Times. 2002 Jan 22 Sect. 7. [ Google Scholar ]
• 72. Millard L. Suicide and the skin. Clin Exp Dermatol. 2001;26(2):211. [ Google Scholar ]
• 73. Bower P, Rowland N, Mellor C, Heywood P, Godfrey C, Hardy R. The Cochrane Library. Issue 4. Chichester: John Wiley & Sons; 2004. Effectiveness and cost effectiveness of counselling in primary care. Cochrane Collaboration. [ Google Scholar ]
• 74. Hickie IB. An approach to managing depression in general practice. Med J Aust. 2000;173(2):106–110. doi: 10.5694/j.1326-5377.2000.tb139255.x. [ DOI ] [ PubMed ] [ Google Scholar ]

Associated Data

This section collects any data citations, data availability statements, or supplementary materials included in this article.

Supplementary Materials

• PDF (91.3 KB)
• Collections

Similar articles

Cited by other articles, links to ncbi databases.

• Download .nbib .nbib
• Format: AMA APA MLA NLM

Add to Collections

Article  

• Volume 28, issue 20
• HESS, 28, 4559–4576, 2024

Multiple terms: term1 term2 red apples returns results with all terms like: Fructose levels in red and green apples

Precise match in quotes: "term1 term2" "red apples" returns results matching exactly like: Anthocyanin biosynthesis in red apples

Exclude a term with -: term1 -term2 apples -red returns results containing apples but not red : Malic acid in green apples

Network problems

Server timeout, empty search term, too many requests.

• Peer review
• Related articles

Solutions and case studies for thermally driven reactive transport and porosity evolution in geothermal systems (reactive Lauwerier problem)

Einat aharonov, piotr szymczak, manolis veveakis, laura e. dalton.

Subsurface non-isothermal fluid injection is a ubiquitous scenario in energy and water resource applications, which can lead to geochemical disequilibrium and thermally driven solubility changes and reactions. Depending on the nature of the solubility of a mineral, the thermal change can lead to either mineral dissolution or precipitation (due to undersaturation or supersaturation conditions). Here, by considering this thermo-hydro-chemical (THC) scenario and by calculating the temperature-dependent solubility using a non-isothermal solution (the so-called Lauwerier solution), thermally driven reactive transport solutions are derived for a confined aquifer. The coupled solutions, hereafter termed the “reactive Lauwerier problem”, are developed for axisymmetric and Cartesian symmetries and additionally provide the porosity evolution in the aquifer. The solutions are then used to study two common cases: (I) hot CO 2 -rich water injection into a carbonate aquifer and (II) hot silica-rich water injection into a sandstone aquifer, leading to mineral dissolution and precipitation, respectively. We discuss the timescales of such fluid–rock interactions and the changes in hydraulic system properties. The solutions and findings contribute to the understanding and management of subsurface energy and water resources, such as aquifer thermal energy storage, aquifer storage and recovery and reinjection of used geothermal water. The solutions are also useful for developing and benchmarking complex coupled numerical codes.

• Article (PDF, 1741 KB)
• Article (1741 KB)
• Full-text XML

Roded, R., Aharonov, E., Szymczak, P., Veveakis, M., Lazar, B., and Dalton, L. E.: Solutions and case studies for thermally driven reactive transport and porosity evolution in geothermal systems (reactive Lauwerier problem), Hydrol. Earth Syst. Sci., 28, 4559–4576, https://doi.org/10.5194/hess-28-4559-2024, 2024.

The recharge or injection of fluids in constrained physical and chemical states in geothermal systems and aquifers is a common phenomenon in both natural and applied systems (Phillips, 2009; Stauffer et al., 2013). In many instances, thermal changes within these systems can shift the system from a state of geochemical equilibrium to disequilibrium and lead to chemical reactions over extensive distances determined by the variations in temperature. These perturbations result from the changes in the solubility of minerals in groundwater, which can become supersaturated or undersaturated in response to thermal changes. These thermally driven reactions cause progressive changes in the rock porosity and hydraulic properties that result from accumulation, removal, or replacement of solid minerals and the accompanied volumetric changes (Phillips, 2009; Woods, 2015). Such processes are responsible for the natural transformations of rocks from diagenesis and metamorphism (Jamtveit and Yardley, 1996; Yardley et al., 2011) to the evolution of aquifers and reservoirs (Andre and Rajaram, 2005; Jones and Xiao, 2006) and melt migration in the Earth's mantle (Aharonov et al., 1995; Kelemen et al., 1995). In applied systems, fluid–rock interactions can significantly impact hydrothermal performance at a timescale of years (Huenges et al., 2013; Pandey et al., 2018).

Depending on the natural solubility of the minerals in the system, an increase in temperature can induce either dissolution or precipitation. This is because mineral solubilities can either increase with temperature (“prograde solubility”) or decrease with it (“retrograde solubility”; Jamtveit and Yardley, 1996; Woods, 2015). Flow and transport commonly influence the state of saturation by continuously introducing thermally disequilibriated fluid, which subsequently becomes geochemically disequilibriated. This occurs because, in many cases, advection serves as the dominant transport mechanism, characterized by a shorter timescale ( t A ) compared to diffusive heat ( t C ) or diffusive solute transport ( t D ) . These timescales are represented by t A = l A / u A , t C = l C 2 / α b , and t D = l D 2 / D , where  l A , l C , and l D  are characteristic length scales of advection, heat conduction, and ionic diffusion, respectively. Here, u A  denotes the characteristic Darcy flux [L T −1 ], while α b  and D  are the bulk thermal diffusivity and ionic diffusion coefficient, respectively. The ratio of these timescales defines the thermal Péclet number ( Pe T = t C / t A ) and the solute Péclet number ( Pe s = t D / t A ), which are used to characterize the transport regime in these systems. When Pe T  and Pe s  are high (i.e.,  ≫1 ), advective transport prevails (Ladd and Szymczak, 2021; Nield and Bejan, 2017; Roded et al., 2020).

The overall integrated action of these mechanisms results in a coupled thermo-hydro-chemical (THC) process (Huenges et al., 2013; Pandey et al., 2018; Phillips, 2009; Regenauer-Lieb et al., 2013). The tightly coupled feedbacks in THC processes commonly render them highly nonlinear. Fluid flow and diffusive heat and solute transport induce chemical reactions, which alter the pore structure and its transport properties, leading to further feedback on flow and transport (Chaudhuri et al., 2013; Phillips, 2009; Woods, 2015). Studying these coupled feedback alterations improves the understanding of reactive transport processes taking place in the Earth's upper crust. Specifically, these studies are integral to the sustainable planning and long-term management of water resources (Andre and Rajaram, 2005; Phillips, 2009), geothermal energy systems (on the scale of tens of years; Frick et al., 2011; Huenges et al., 2013; Pandey et al., 2018), and CO 2 geo-sequestration (Dávila et al., 2020; Steefel et al., 2013; Tutolo et al., 2015).

In enhanced geothermal systems (EGSs) in particular, channelized dissolution can create a short circuit and reduce the heat exchange between the rock and the fluid. Conversely, precipitation can significantly reduce permeability, leading to reduced production and potentially sealing reservoirs (Huenges et al., 2013; Olasolo et al., 2016; Pandey et al., 2018). Another challenge associated with geothermal utilization is the risk of groundwater contamination, where thermal changes can lead to the leaching of undesired chemical species from the rocks. Specifically, contamination may arise from the reinjection of fluids required to maintain reservoir pressure from aquifer thermal energy storage (ATES) systems that leverage seasonal temperature fluctuations (Bonte et al., 2014; Glassley, 2014; Possemiers et al., 2014). It may also result from substantial injections of hotter or colder water for groundwater management practices, such as aquifer storage and recovery (ASR) (Maliva, 2019; Zheng et al., 2021).

In terms of mineralogy, a range of thermally driven reactions occurs in the previously mentioned systems. Commonly reported precipitates accumulating in geothermal plant piping loops and natural spring deposits include carbonates (e.g., calcite, dolomite, and siderite), sulfates (e.g., gypsum and baryte), and amorphous silica (Glassley, 2014; Huenges et al., 2013). Particularly, geothermal systems composed of sandstones and carbonates are ubiquitous in the Earth's crust and are prone to alterations (Goldscheider et al., 2010; Pandey et al., 2018; Wood and Hewett, 1984). The solubility of silica is proportional to temperature (i.e., prograde solubility), and water pumping or injection can lead to substantial changes in reservoir transmissivity that can affect heat extraction (Pandey et al., 2018; Rawal and Ghassemi, 2014; Taron and Elsworth, 2009). In particular, silica precipitation can occur several orders of magnitude faster than the dissolution of either quartz minerals or amorphous silica (Rimstidt and Barnes, 1980). The exception is the dissolution of unconsolidated amorphous silica sediments (e.g., diatomite). Due to the high specific reactive surface area of the material, these sediments can be intensely dissolved when steam and hot water undersaturated with respect to silica are injected (Bhat and Kovscek, 1998). In contrast to silica, carbonate minerals demonstrate an inverse relation (i.e., retrograde solubility), which is often strong and influenced by CO 2 content. Consequently, limestone and dolomite aquifers and reservoirs subjected to geothermal flows, commonly rich in CO 2 , can evolve at relatively short timescales. Either rapid dissolution or rapid precipitation can occur in such systems depending on conditions (Andre and Rajaram, 2005; Coudrain-Ribstein et al., 1998; Roded et al., 2023).

Investigating the multi-physical systems of THC processes is complex and relies on numerical models facilitated by ongoing advancements in computational capabilities (Kolditz et al., 2016; Pandey et al., 2018; Steefel et al., 2015). Over recent decades, these models have improved the understanding of subsurface processes (Niemi et al., 2017; Regenauer-Lieb et al., 2013; Seigneur et al., 2019; Steefel et al., 2013); however, the validity of such models remains questionable if the results cannot be rigorously tested (Kolditz et al., 2016; Nield and Bejan, 2017). Particularly, analytical solutions allow for the establishment of functional relationships between variables and physical properties and provide robust reliability and accuracy tests for numerical models (Bear and Cheng, 2010; Diersch and Kolditz, 2002; Nield and Bejan, 2017). However, comprehensive testing of multi-coupled THC codes is often mathematically cumbersome and precluded by many different approaches. This limitation arises because existing theoretical solutions focus solely on scenarios related to heat and/or solute transport (Diersch and Kolditz, 2002; Nield and Bejan, 2017; Stauffer et al., 2013; Turcotte and Schubert, 2002) or reactive solute transport (Bear and Cheng, 2010; Nield and Bejan, 2017) and because complete solutions that involve coupled THC processes are scarce (White et al., 2018). To the best of the authors' knowledge, coupled THC solutions are limited to two scenarios: thermally driven reactive front development (Jupp and Woods, 2003, 2004) and thermal and/or solutal convection in a reactive medium (e.g., Rayleigh–Bénard equivalent in a reactive porous medium; Al-Sulaimi, 2015; Corson and Pritchard, 2017). Solutions for fundamental and practical situations in geothermal and groundwater systems, such as non-isothermal injection into a reservoir and consequent matrix modifications, are missing. This is despite the existence of the so-called “Lauwerier solution” (Lauwerier, 1955), which analytically predicts the thermal field resulting from hot (or cold) fluid injection into a thin non-reactive confined layer system. The Lauwerier solution has served as the basis for the development of multiple modified heat transport solutions, accounting for various boundary conditions and system geometries, considering conduction and dispersion, and even accommodating fractured media (Abbasi et al., 2017; Chen and Reddell, 1983; Lin et al., 2019; Shaw-Yang and Hund-Der, 2008; Voigt and Haefner, 1987; Yang et al., 2010; Zhou et al., 2019; Ziagos and Blackwell, 1986; see review in Stauffer et al., 2013).

In the present work, we present analytical solutions, invoking non-isothermal fluid injection from a point or planar source into a thin confined aquifer (essentially the same scenario as of the Lauwerier problem). However, in this study, thermal changes drive the reactions and porosity evolution. Here, we define and solve the coupled physics of the “reactive Lauwerier problem”. To achieve this, we employ a temperature-dependent solubility in a reactive-flow formulation, while accounting for the thermal field following the Lauwerier formulation. The equations are solved for radial and planar flows, and the general solutions are applied to two common scenarios: carbonate dissolution and silica precipitation with respective permeability evolutions of each.

2.1   Reactive Lauwerier scenario and the conceptual model

We consider Lauwerier problem settings (Lauwerier, 1955; Stauffer et al., 2013) involving the injection of hot (or cold) fluid into a confined aquifer located between bedrock and caprock, with lateral flow along the coordinate  φ . The latter can represent the radial coordinate in an axisymmetric setting or x  in Cartesian coordinates; i.e., φ = r or  x . Figure 1 illustrates a summary of the problem, while Appendix F provides a summary of the nomenclature.

Figure 1 Sketch of the reactive Lauwerier problem and the conceptual model for thermally driven reactive transport in geothermal systems (the radial case). Hot (or cold) fluid is injected into a confined aquifer between aquiclude bedrock and caprock at a constant flow rate,  Q , and temperature,  T in . The initial temperature of the aquifer is  T 0 , and its thickness is  H . Downstream, along the flow path, heat is conducted from the aquifer through the confining layers. Thermal variations in the aquifer (color gradients) induce a change in solubility,  c s ( T ) , and hence disequilibrium and reaction, which in turn drive the evolution of the porosity of the aquifer from its initial value,  θ 0 . z  represents the vertical coordinate. In the main text, both polar and Cartesian geometries are considered, with φ = r or  x , respectively. The origin of  φ and z  is defined at the center of the injection well. The injection well exhibits either axial (as shown in the sketch) or planar symmetry if Cartesian geometry is considered.

Downstream, along the flow path away from the injection point, heat is exchanged between the aquifer and the impermeable confining rock layers. Within the confining layers, heat is transported by conduction alone. The heat exchange and thermal variations in the aquifer induce changes in the solubility of the minerals (i.e., saturation concentration,  c s ( T ) ), which in turn trigger undersaturation and dissolution reactions or, conversely, supersaturation and precipitation reactions that modify the aquifer porosity,  θ . Both removal or accumulation of minerals can occur depending on the injection temperature (colder or warmer than ambient) and the prograde or retrograde nature of the reactive minerals. Our radial setup pertains to injection from a single well or mimics natural localized thermal upwelling in fractured/faulted media of deep origin, discharging into the shallower aquifer (Craw, 2000; Micklethwaite and Cox, 2006; Roded et al., 2013, 2023; Tripp and Vearncombe, 2004). The planar source setup simulates injection wells arranged in a straight line (Lauwerier, 1955).

2.2  Main model assumptions

Here, the THC conceptual model shown in Fig. 1 is mathematically described using conservation equations for heat and reactive transport along with initial and boundary conditions. The thermal Lauwerier solution and the mathematical model involve several simplifying assumptions, the major ones of which are listed below. For a more comprehensive overview, expanded versions of the conservation equations are provided in Appendix A.

The underlying thermal assumptions include negligible basal (background) geothermal heat flow and an initial geothermal gradient compared to the heat input by the injected fluid. The aquifer is located at a significant depth, preventing heat transport to the surface; otherwise, greater heat exchange would occur between the aquifer and the caprock. This assumption regarding the depth also depends on the timescale of interest: the thermal front, which ascends with time, may not reach the surface on a short timescale. However, it may transport heat to the surface after a longer time (which can be estimated using  t C ).

Heat transport in the layers confining the aquifer is described by conduction and only in the vertical direction ( z ) , neglecting lateral ( φ ) heat conduction. This assumption limits the applicability of the solution to scenarios involving large injected fluid fluxes. To assess the validity of this assumption, a thermal Péclet number, which compares heat advection in the aquifer to lateral heat conduction, Pe T = u A l / α b , is used. Pe T  involves a length scale,  l , at which substantial temperature variation occurs (e.g., larger than 2 % from the total temperature change,  Δ T ). An analysis using the parameter values in Table 1 and the results in Sect. 3 (i.e., a posteriori inspection) confirm that Pe T ≫1 at all times. Additionally, beyond the very early moments, the length scale of l should be larger than the vertical dimension of the aquifer,  H , at which complete thermal mixing is assumed ( l ≫ H ). This assumption may not be applicable if a thick aquifer (i.e., large  H ) is considered and substantial vertical temperature gradients are expected to develop.

Furthermore, conduction and solute diffusion within the aquifer groundwater are neglected because the respective thermal ( Pe T ) and solute ( Pe s ) Péclet numbers are assumed to be large. Fluid and solid properties, such as density and heat conductivity, are considered constant and independent of temperature. It is noted that for CO 2 applications, the assumption of constant density and incompressibility may not be appropriate for a CO 2 -rich phase (supercritical or gas) with moderate temperature changes (e.g., Δ T >40  °C).

Furthermore, the specific reactive surface area,  A s ( L 2 to L −3  of the porous medium), is considered constant here and assumed not to change as reaction progresses. In most instances, this assumption does not weaken the applicability of the solution since A s  may vary widely across different rock lithologies, e.g., from 10 −1  m −1 in fractured media (Deng and Spycher, 2019; Pacheco and Van der Weijden, 2014) to above 10 5  m −1 for porous rocks (Mostaghimi et al., 2013; Noiriel et al., 2012; Seigneur et al., 2019) and can often only be estimated very roughly (e.g., within an order of magnitude accuracy). Furthermore, A s  can evolve with the reactive flow in a way that is difficult to estimate (Noiriel, 2015; Seigneur et al., 2019). If large porosity changes occur, the inherent assumption of a constant  A s can limit the applicability of the solutions.

2.3  The basic conservation equations

Neglecting heat conduction in the radial direction,  r , the heat conduction equation in the rock confining the aquifer above and below is given by

where T  represents temperature; t  denotes time; z  is the vertical coordinate, with its origin at the center of the injection well; and H  is the aquifer thickness (see Fig. 1). The quantity α b = K b / C p b is the thermal diffusivity [L 2  T −1 ], where the subscript b indicates bulk rock, K  is the thermal conductivity, and C p  is the volumetric heat capacity (Chen and Reddell, 1983; Stauffer et al., 2013).

Assuming that heat transport in the fluid along the aquifer is governed by advection and that complete mixing occurs in the aquifer transverse direction ( z ), a depth-averaged heat-transport equation can then be formulated for the aquifer region:

where subscript f denotes fluid and u ( r )  is the radial superficial velocity (or Darcy flux), which can be determined from the total volumetric flow rate,  Q , using u = Q / ( H 2 π r ) (assuming u  to be uniform along the z  direction of the aquifer; Andre and Rajaram, 2005; Lauwerier, 1955). Function  Θ accounts for the heat exchange between the aquifer and the confining rock located above and below, calculated using Fourier's law, with continuous temperature assumed at the interfaces:

The factor of 2 accounts for the rock both above and below the horizon (Stauffer et al., 2013).

The solute transport advection–reaction equation in the aquifer is

Here, c  is the solute concentration [M L −3 ] and Ω  is the reaction term (Chaudhuri et al., 2013; Szymczak and Ladd, 2012). Equation (4) is derived by neglecting transient and diffusive terms in the advection–diffusion–reaction equation (Eq. A3). The justification for the quasi-static approximation used when deriving Eq. (4) lies in the separation of timescales between heat conduction ( t C ) in the confining rocks and mineral alteration ( t M ) and the relaxation of solute concentration ( t A ) (for in-depth analysis and discussion, see Appendix B and, e.g., Detwiler and Rajaram, 2007; Ladd and Szymczak, 2017; Lichtner, 1991; Roded et al., 2020; Sanford and Konikow, 1989).

Here, we assume a surface-controlled reaction and first-order kinetics:

where A s  is the specific reactive surface area and λ  is the kinetic reaction rate coefficient [L T −1 ], here assumed to be constant (Dreybrodt et al., 2005; Seigneur et al., 2019). Λ is denoted as the solute disequilibrium and is defined as the difference between the concentration of dissolved ions and saturation (equilibrium) concentrations,  c s ,

Thus, the solute disequilibrium,  Λ , is negative for undersaturation and positive for supersaturation. c s  is calculated as follows:

Here, T 0  represents the initial temperature in the aquifer and the parameter β = ∂ c s / ∂ T . Equation (7) assumes a linear relationship between  c s and  T , with a constant proportionality factor,  β , which is positive for minerals of prograde solubility and negative for minerals of retrograde solubility (Al-Sulaimi, 2015; Corson and Pritchard, 2017; Woods, 2015).

Given the reaction rate (Eq. 5), the change in porosity,  θ , can be calculated as follows:

where c sol  is the concentration of the soluble solid mineral and ν  accounts for the stoichiometry of the reaction. In the case of planar flow and Cartesian coordinates, r  can be replaced by  x in the equations above, while Eq. (2) takes the following form:

where u here is the spatially uniform fluid velocity in the x direction.

2.4  Initial and boundary conditions

The initial conditions involve a uniform value of temperature  T 0 throughout the medium. The boundary conditions at the injection well ( φ =0 ) include a constant rate of fluid injection at temperature  T in and initially zero solute disequilibrium, Λ=0 (Eq. 6). The caprock and bedrock thickness and aquifer extent are assumed to be infinite.

2.5  Solution of the reactive Lauwerier problem

2.5.1  axisymmetric (radial) flow, aquifer temperature.

The solution of Eqs. (1) and (2) for the temperature distribution in the aquifer (known as the Lauwerier solution) for the radial case is given by

Here, erfc is the complementary error function, Δ T = T in - T 0 is the difference between injection and initial aquifer temperature, and ζ  is defined as

The time variable, t ′ = t - 2 r C p b / ( C p f u ) , and the solution given by Eq. (10) holds when t ′ > 0 (Stauffer et al., 2013). We additionally assume long enough time and conditions where t ′ ≈ t (see Appendix C for analysis of the validity of this assumption). Furthermore, to simplify the equations, we assume equal heat capacities for both the confining rocks and the aquifer. To account for non-uniform heat capacities alternative form of Eq. (10) can be used (refer to Eqs. 3.122 and 3.131 and associated definitions in Stauffer et al., 2013).

Reactive solute transport

We begin by substituting Eq. (6) into Eq. (4) to obtain

The derivative ∂ c s / ∂ r can then be expressed by differentiating the relationship in Eq. (7),

and further substituting Lauwerier solution (Eq. 10), which provides

Next, substituting Eq. (14) into Eqs. (13) and (12) results in a linear inhomogeneous differential equation. Assuming saturation conditions at the inlet and the boundary condition of Λ ( r = 0 ) = 0 leads to the following solution:

where erf is the error function and η = H π A s λ / Q . Appendix D presents an approximation for Eq.  (15) which is useful for efficient computation and prevents integer overflow (Press et al., 2007).

Given the reaction rate (Eq. 5), the erosion and porosity change can be calculated using the solid erosion equation (Eq. 8). Substituting Eq. (15) into Eq. (8), integrating over time, and using the initial condition of θ ( t = 0 ) = θ 0 results in a closed-form expression for the temporal and spatial evolution of porosity,  θ :

2.5.2  Planar flow

In the Cartesian case, with injection along a line, the Lauwerier solution is

where ω  is defined as

and t ′ = t - x C p b / ( C p f u ) . Similarly, to the radial case, the solution holds at sufficiently long times, for which t ′ ≈ t .

Following the analogous steps as in the radial case, the solution is derived by

where σ = A s λ / u .

In this section, we use the radial solutions presented in the previous section to examine two common scenarios: (I) injection of CO 2 -rich hot water into a carbonate aquifer and (II) injection of silica-rich hot water into a sandstone aquifer. These scenarios result in cooling-induced calcite dissolution and silica precipitation, respectively. The subsequent porosity evolution within these systems (Eqs. 16 and 20) is then used to estimate the evolution of aquifer permeability. These scenarios are pertinent, for instance, in aquifer thermal storage, reinjection of geothermal water at shallow depths, or applications of groundwater storage and recovery (Diaz et al., 2016; Fleuchaus et al., 2018; Maliva, 2019).

3.1  Aquifer properties and injection conditions

Here, we discuss conditions for thermally induced reactivity in carbonates and sandstone aquifers and the parameter values assigned in the simulations (Table 1). Regarding the description of the kinetics of these systems, calcite dissolution can often be complex, involving various chemical species and reactions of varying orders (Dreybrodt, 1988; Plummer et al., 1978). However, for a wide range of pH values, it can be simplified and described by assuming a linear dependence on undersaturation or acid concentration. Specifically, first-order kinetics are commonly employed to study natural karst formations (pH  ∼  6; Dreybrodt et al., 2005; Palmer, 1991), and dissolution under the acidic conditions common in engineering applications (pH  ∼  3; Hoefner and Fogler, 1988; Peng et al., 2015) or in geothermal systems of high CO 2 partial pressure, PCO 2 (pH ∼  5; Coudrain-Ribstein et al., 1998; Lu et al., 2020; Roded et al., 2023). Silica precipitation can be well described by first-order kinetics (Carroll et al., 1998; Ji et al., 2023; Pandey et al., 2015; Rimstidt and Barnes, 1980).

Table 1 Parameter values used in the simulations.

a  Glassley (2014). b  Huenges and Ledru (2011). c  Palmer (1991). d  Rimstidt and Barnes (1980). e  See text. f  Hussaini and Dvorkin (2021) and Lai et al. (2015). g  Roded et al. (2023).

Download Print Version | Download XLSX

We also exploit approximately linear temperature–solubility dependence over the temperature range studied here (between T 0 =20  °C and T in =60  °C) and assign a constant value to β  (Eq. 7; Andre and Rajaram, 2005; Glassley, 2014; Rimstidt and Barnes, 1980; Roded et al., 2023). Additionally, it should be noted that in carbonates, the temperature–solubility relation strongly depends on PCO 2 : higher PCO 2 values result in larger increases in  c s as the water cools (i.e., the magnitude of  β is larger; see Fig. 2b in Roded et al., 2023, and Andre and Rajaram, 2005; Palmer, 1991). Here, in accordance with typical conditions in geothermal systems, we consider injection of water with PCO 2   =  0.03 MPa (Coudrain-Ribstein et al., 1998; Lu et al., 2020).

In the simulations, we assign characteristic porosity ( θ ) and reactive surface area ( A s ) for the different aquifer types. In accordance with common field observations, we consider a carbonate aquifer in which flow and dissolution are focused in the permeable fracture network and a porous sandstone aquifer characterized by high intergranular permeability (Bear and Cheng, 2010; Jamtveit and Yardley, 1996). The different aquifer characteristics are reflected in significant differences in θ  and A s  for the different aquifer types. Specifically, carbonates are often characterized by permeability contrasts spanning orders of magnitudes between the fractures and the rock matrix (Dreybrodt et al., 2005; Lucia, 2007). Consequently, transport in the matrix occurs mostly by slow diffusion, and the reaction within the matrix can be neglected. Hence, only the reactive surface area,  A s , of the fractures effectively participates in the reaction (Deng and Spycher, 2019; Maher et al., 2006; Pacheco and Alencoão, 2006; Seigneur et al., 2019). In this case, θ  can be minimal (Lucia, 2007) and A s  is orders of magnitude smaller compared to its value in porous sandstones (Hussaini and Dvorkin, 2021; Lai et al., 2015; Pacheco and Alencoão, 2006; Pacheco and Van der Weijden, 2014; Seigneur et al., 2019). This disparity can lead to substantial differences in characteristic alteration rates and Damköhler numbers in these systems (Ladd and Szymczak, 2021; Lucia, 2007; Seigneur et al., 2019).

Specifically, in the case of fractured rocks as described above, we calculate the reactive surface area using A s = 2 ⋅ κ ⋅ RF , where κ  is the fracture density (defined as the number of fractures per unit volume), the factor of 2 accounts for the presence of two surfaces, and RF is the roughness factor (Deng et al., 2018). Assuming κ = 1 / 3 3  m −3 and RF  =  1.35 results in A s =0.1  m −1 . Typical values of  κ and fracture spacing can span a substantial range and may be higher or lower (Narr and Suppe, 1991; Scholz, 2019). Here, it is further assumed that the fracture density is high and the network is of high connectivity, allowing it to be treated as a continuum (Anderson et al., 2015; Sahimi, 2011). We consider here an injection flow rate of Q =500  m 3  d −1 , which falls within the typical range of flow rates observed in relevant applications, such as geothermal systems (Glassley, 2014) or groundwater storage and recovery (Maliva, 2019). The injection temperature is set to T in =60  °C, and aquifer ambient temperature is set to T 0 =20  °C ( Δ T =40  °C). To obtain the results, in this section, the solutions were implemented in MATLAB code (MATLAB, 2022). Appendix D details the use of the approximated Eq. (D2) in calculating the results in Figs. 2 and 3.

Figure 2 Carbonate aquifer dissolution by cooling hot water. Temperature,  T ; solute disequilibrium,  Λ ; and porosity, θ , in the aquifer are plotted as functions of the radial position,  r , at different times (computed using Eqs. 10, 16, and D2). (a)  The hot flow cools gradually as it travels through the aquifer, transferring heat to the confining rocks, thereby causing them to warm over time and the thermal front to progress downstream. (b)  Cooling induces undersaturation (negative disequilibrium,  Λ ; see Eq. 6), which is of a relatively small magnitude due to the rapid kinetics of calcite dissolution. Λ  is normalized by the total solubility change in the system,  Δ c s (refer to the text for the definition of  Δ c s ). The water is hot and saturated at the inlet, c = c s ( T in ) . Undersaturation quickly develops near the inlet ( r ≈20  m, as shown in the magnification) and then gradually diminishes due to dissolution reactions further along the flow path ( Λ  approaches zero). As the thermal front propagates over time, and thermal gradients diminish, the Λ  curves also flatten. (c)  Corresponding to Λ  variations, a porosity profile develops over time (see the magnification for the inlet-adjacent region).

Figure 3 Silica precipitation in a sandstone aquifer by cooling hot water. The calculated solute disequilibrium,  Λ , and porosity,  θ , as functions of the lateral position,  r , are shown at different times since the beginning of the injection (calculated using Eqs. 16 and D2; the temperature profile is given in Fig. 2a). The reactive transport processes in this case are similar to the carbonate dissolution system shown in Fig. 2, with insets Fig. 2b and c being approximately mirror images of panels  (a) and  (b) , showing supersaturation and porosity reduction. (a)  As a result of cooling, solute disequilibrium corresponding to supersaturation ( Λ ; Eq. 6) develops, which is of a small magnitude due to the high reaction rates ( Λ  is scaled by the total solubility change in the system,  Δ c s ; refer to the text for the definition of Δ c s ). The water enters hot and saturated at the inlet, c = c s ( T in ) , and, subsequently, Λ  increases rapidly and then gradually diminishes downstream due to the reaction. The advancement of the thermal front over time and lower gradients lead to the flattening of Λ  curves. (b)  In accordance with  Λ , an extensive porosity profile develops over time.

3.2  Carbonate aquifer dissolution by cooling water

In Fig. 2, the results of CO 2 -rich hot water injection into a carbonate aquifer at successive times since the beginning of the injection are shown (Eqs. 10, 16, and D2 are solved for t =0.2 , 10, and 100 kyr). During the radial flow within the aquifer, the hot fluid cools by transferring heat into the confining layers, which heat up with time, resulting in the gradual advancement of the thermal front downstream (Fig. 2a). The cooling induces solute disequilibrium ( Λ ) associated with undersaturation (note that Λ  is negative for undersaturation and positive for supersaturation; see Eq. 6). The magnitude of  Λ in the aquifer is small compared to the absolute solubility change in the system, Δ c s = | c s ( T in ) - c s ( T 0 ) | , i.e., between c s ( T in ) at the injection point and c s ( T 0 ) at ambient conditions ( | Λ | / Δ c s ≪ 1  %; see Fig. 2b). The small magnitude of disequilibrium is associated with relatively high PCO 2 considered here (0.03 MPa) and rapid kinetics under these conditions. The quasi-equilibrium conditions may allow for the simplification and calculation of the local reaction rate from transport processes alone, regardless of kinetics, referred to as the so-called “equilibrium model” (Andre and Rajaram, 2005; Bekri et al., 1995; Golfier et al., 2002; Lichtner, 1991), which will be the subject of a future research.

Although the magnitude of disequilibrium,  Λ , is small, it controls the alteration of the aquifer and the evolution of its properties. Significantly, because the water at the inlet is hot and saturated with calcite, c = c s ( T in ) , disequilibrium, and reaction rate are zero at the inlet, leading to no change in the porosity there (see Figs. 2b and 3c and their magnifications). Disequilibrium (undersaturation) sharply develops downstream of the injection site, first forming a small minimum (at r ≈20  m) and gradually increasing to zero at greater distances. Undersaturation and dissolution along the flow path are controlled by the interplay of three processes: (I) dissolution reducing undersaturation (i.e., Λ  becomes closer to zero), (II) progressive cooling increasing undersaturation, and (III) advection–transport–reaction products (i.e., calcium ions) radially outward from the well, helping maintain undersaturation. Here, the effect of fluid velocity and advection decays with a distance of  1 / r .

High advection and cooling rates near the inlet result in the abrupt formation of undersaturation (i.e., negative  Λ ). Further downstream, undersaturation diminishes due to dissolution reactions. As the thermal front advances downstream over time and the temperature gradients diminish along the aquifer, the Λ  curve flattens and becomes more elongated (see curves for t =10 and 100 kyr in Fig. 2b). Due to the disequilibrium, porosity grows with time. The porosity sharply increases near the inlet and then gradually decreases downstream (Fig. 2c). The porosity changes are extensive and take place over an aquifer area of ∼30  km 2 within a relatively short geological timescale of 100 kyr, resulting in the addition of significant void space of thousands of cubic meters ( ∼ 5 × 10 3  m 3 ).

An essential assumption underlying the solutions in Sect. 2 and the results depicted in Fig. 2 is the assumption of spatial uniformity and symmetry of reactive flow. In practical scenarios, however, dissolution instabilities can emerge at the reaction front. These instabilities, owing to the positive feedback between reaction and transport, may evolve into dissolution channels, often referred to as wormholes (Aharonov et al., 1997; Budek and Szymczak, 2012; Chadam et al., 1986; Ortoleva et al., 1987; Roded et al., 2018, 2021). The wormholes concentrate reactive flow, resulting in heterogeneous flow fields that cannot be accurately represented by assuming symmetry and uniformity. In such a case, the results of Fig. 2 can only be regarded as an average solution, which is not accurate locally.

Isothermal dissolution, driven by undersaturation of the incoming solution is known to be unstable in the radial geometry for a large-enough solute Péclet number,  Pe s , and intermediate Damköhler numbers. The Damköhler number here is given by D a = A s λ l A / u A and represents the ratio between advective and reactive timescales (Daccord, 1987; Grodzki and Szymczak, 2019; Kalia and Balakotaiah, 2007; Xu et al., 2020). However, in our case, the cooling of the solution renews its aggressiveness, hence extending the penetration length in the system which may influence the stability of the reactive front (Xu et al., 2020). The effect of renewed aggressiveness by considering solubility gradients was studied for planar reactive flow in Aharonov et al. (1997) and Spiegelman et al. (2001) but requires further investigation for radial flow and taking into account coupling with heat transfer.

3.3  Silica precipitation by cooling water

Here, we consider the injection of hot silica-rich water that cools, becoming supersaturated and leading to silica precipitation, consequently reducing void space and permeability. While the previous case involved dissolution, this one involves precipitation; however, the thermal and reactive transport processes are similar in both cases (with approximately mirror-image  Λ and θ  profiles; see Figs. 2b, c and 3a, b).

Similarly to the previous section, the low magnitude of  Λ suggests that the reaction rate (Eq. 5) is relatively high compared to transport processes, effectively reducing disequilibrium,  Λ . It is noted that the reaction rates are high in both systems despite the orders-of-magnitude differences in the kinetic rate coefficient ( λ = 10 - 6  m s −1 for calcite dissolution compared to 5 × 10 - 10  m s −1 for silica precipitation). However, this difference is largely compensated by the contrast between the reactive surface area of the porous sandstone and fractured carbonate aquifers ( A s =10 4  m −1 compared to 10 m −1 , respectively). It should also be noted that while precipitation of crystalline and non-crystalline (amorphous) silica is characterized by relatively high rates, dissolution of quartz and silica polymorphs is typically slower by several orders of magnitude (Rimstidt and Barnes, 1980).

While the reaction rates are high in both systems, differences exist in the absolute magnitude of porosity change resulting from the injection. For example, the maximal porosity change in the aquifer due to silica precipitation is approximately Δ θ max ≈0.03 , whereas for the carbonate case it is around Δ θ max ≈0.08 (where Δ θ max = | θ max ( t = 100 kyr ) - θ 0 | and θ max  denote the maximal porosity change along the profile). The predicted lower porosity change in silica arises mostly due to its lower total solubility change,  Δ c s , and the reduced dependence of mineral solubility on temperature, expressed here by the β  parameter (see Table 1). This conclusion is further supported by the fact that no disequilibriated fluid exits the system: the fluid flows out from the system at r =3000  m at a temperature that is close to the ambient temperature,  T 0 (Fig. 2a), and chemically equilibrated ( Λ=0 ; Figs. 2b and 3a).

3.4  Permeability evolution of the aquifers

The porosity changes affect the aquifer hydraulics. Here, we calculate the effective aquifer permeability,  k eff , within a distance,  R , around the well. k eff  is calculated based on the relationship between the local porosity and permeability, utilizing the power-law relation k ( r ) / k 0 = ( θ ( r ) / θ 0 ) n , where k 0  and θ 0  are the initial permeability and porosity (the steps for the calculation of  k eff are presented in Appendix E). The exponent  n depends on various factors, such as medium microstructural details and the nature of the alteration processes (Seigneur et al., 2019; Steefel et al., 2015; Vafaie et al., 2023). The limited predictive capabilities of k – θ relations, including instances where counter trends of porosity and permeability changes occur (Garing et al., 2015), have been previously noted (e.g., Sabo and Beckingham, 2021). Here, it is applied to evaluate general trends, which, with the exception of unique cases, remain valid regardless of the porosity–permeability relation used.

The wide range of heterogeneous microstructures in rocks and sediments and their response to different reactive-flow regimes lead to a large variability in the exponent n  values. For example, for relatively uniform spatial dissolution, n  can range from  ∼3 to a few dozen for the early stages of flow or when wormholes develop (Hao et al., 2013; Roded et al., 2020; Vafaie et al., 2023). For precipitation, n  typically ranges from  ∼2 up to above 10 (Aharonov et al., 1998; Hommel et al., 2018; Seigneur et al., 2019).

Figure 4 shows k eff  evolution over time for representative exponent values within a distance of R =3  km. The rapid increase in carbonate aquifer permeability indicates (in agreement with previous works, Agar and Geiger, 2015; Andre and Rajaram, 2005; Dreybrodt et al., 2005) that k eff  can be substantially altered within relatively short geological timescales. Specifically, the results suggest that k eff  can even increase by several tens of percents within tens to hundreds of years. Conversely, significant k eff  alterations due to silica precipitations (10 %–50 % reduction) involve typical timescales of tens of thousands of years. These findings are consistent with previous observations of dissolution and precipitation driven by a solubility gradient (e.g., Aharonov et al., 1997), emphasizing differences between these processes, as embodied in the exponent  n . Moreover, under constant pressure (instead of constant flux) boundary conditions, this effect will be enhanced due to a positive (negative) feedback during dissolution (precipitation) (Aharonov et al., 1997).

Figure 4 Evolution of aquifer effective permeability due to dissolution and precipitation. The effective permeability is  k eff , and t  is time; red and blue curves designate carbonate dissolution and silica precipitation, respectively. k eff  is calculated within a radius of R =3  km from the well and is normalized by its initial value, k 0 . The power-law θ – k relation is used to determine  k eff from the local porosity,  θ ( r ) , and permeability,  k ( r ) , with typical exponent values of n =3 –20 for dissolution and n =2 –8 for precipitation. k eff  can be substantially altered in carbonate aquifers due to dissolution even within tens to hundreds of years, while tens of thousands of years are required for similar magnitudes of change caused by silica precipitation.

In this paper, we considered non-isothermal injection into a confined aquifer and the settings and solution of the so-called Lauwerier problem to derive coupled thermally driven reactive transport solutions (reactive Lauwerier problem). The presented solution is among the very limited number of analytical solutions available in the field of thermo-hydro-chemical (THC) flows in porous media. The THC scenarios considered here involved geochemical disequilibrium and reactions induced by thermally driven solubility changes, leading to mineral dissolution or precipitation. In the first section, solutions were derived for the evolution of solute concentration in radial and planar cases. These derivations utilized the non-isothermal Lauwerier solution to calculate the temperature-dependent solubility, which was then substituted into the reactive transport equation. Subsequently, the obtained concentration closed-form solutions were used to derive expressions for the porosity change in the aquifer.

In the second section, these solutions were employed to study two common cases in geothermal and water resource systems, exhibiting opposite feedback on porosity evolution: (I) injection of hot CO 2 -rich water into a fractured carbonate aquifer, leading to cooling and dissolution, and (II) injection of hot silica-rich water into a sandstone aquifer, leading to silica precipitation. The resulting porosity profiles were then used to calculate the hydraulic changes and effective aquifer permeabilities. The results show that the timescale of porosity development in these systems is on the order of thousands to tens of thousands of years depending on the THC conditions (in agreement with previous works, Andre and Rajaram, 2005; Roded et al., 2023). Despite the often faster kinetics of carbonate dissolution compared to silica precipitation, similar timescales are observed in both systems. This is attributed to the high specific reactive surface area of sandstones, which enhances the reaction rate, compensating for the differences in kinetics between carbonate dissolution and silica precipitation. However, substantial hydraulic changes occur much faster in dissolving carbonate aquifers, possibly within tens to hundreds of years, primarily due to the rapid enhancement of permeability resulting from dissolution and a flow-enhanced feedback.

It is worth noting that under the typical conditions considered, the reaction rates are high and the geochemical disequilibrium in these systems is minimal (i.e., quasi-equilibrium). In such conditions, the equilibrium assumption, which simplifies calculations in the reactive Lauwerier problem and comprises an ongoing area of inquiry, may be applied. The solutions and analyses provided contribute to the understanding of natural and engineered hydrothermal systems, such as aquifer storage and recovery (ASR) and thermal energy storage (ATES) applications. Additionally, these solutions can aid in the development and benchmarking of coupled numerical models.

A1  Aquifer temperature

Assuming radial symmetry and that heat transport through the rocks confining the aquifer is governed by conduction, the heat equation in polar coordinates becomes

where T  is the temperature; t  is time; r  and z  are the radial and vertical coordinates, respectively, with their origin at the injection well center; and H  is aquifer thickness (see Fig. 1). The quantity α b = K b / C p b is the thermal diffusivity, where the subscript b denotes bulk rock, K  is the thermal conductivity, and C p  is the volumetric heat capacity (Stauffer et al., 2013).

Assuming that heat transport in the fluid within the aquifer is governed by advection and conduction, the heat-transport equation can then be expressed as

where subscript f denotes fluid and u ( r )  is the radial superficial velocity (or Darcy flux) and can be calculated from the total volumetric flow rate,  Q , using u = Q / ( H 2 π r ) (assuming uniformity of  u along the z  direction of the aquifer; Andre and Rajaram, 2005; Chaudhuri et al., 2013).

Assuming complete thermal mixing in the transverse direction ( z ) of the aquifer allows us to establish the depth-averaged Eq. (2) in the main text. In this case, the heat exchange between the aquifer and the confining rocks is integrated within the heat exchange term ( Θ ).

A2  Reactive transport

Similarly, the solute transport advection–diffusion–reaction equation in the aquifer is

where c  is the solute concentration [M L −3 ], D  is the molecular diffusion coefficient, and Ω  is the reaction term (Chaudhuri et al., 2013; Szymczak and Ladd, 2012). The equations describing the reaction term,  Ω ; saturation concentration, c s ; dependence on the temperature; and porosity change are given in Sect. 2.3 in the main text (Eqs. 5, 7, and 8, respectively).

In the case of planar flow and Cartesian coordinates, Eqs. (A1)–(A3) above take the following form:

Here u is the constant velocity in the x direction.

In our reactive transport calculations and Eq. (4) used for developing the solutions in Sect. 2, we adopt the quasi-static approach (Detwiler and Rajaram, 2007; Ladd and Szymczak, 2017; Lichtner, 1991; Roded et al., 2020; Sanford and Konikow, 1989) and neglect the transient term (present in Eqs. A3 and A6). However, it is noted that temporal variations may take place due to changes in the temperature field and their effect on the solubility, as arises from Eq. (7).

The justification for the quasi-static assumption lies in the significant separation of characteristic timescales in the system. There are three important timescales in our problem: (I) the timescale governing reactant transport ( t A ), (II) the timescale of mineral chemical alteration ( t M ), and (III) the characteristic timescale of conductive heat transport ( t C ). The latter affects the solubility of aquifer minerals, thus influencing reaction and solute transport. Specifically, the conditions for the validity of quasi-static assumption are that t C  and t M  are several orders of magnitude larger compared to reactant transport relaxation time,  t A (i.e., t A ≪ t M and t A ≪ t C ).

For example, in relatively fast-reacting natural carbonate systems, the doubling of initial pore size or fracture aperture due to dissolution typically occurs over a timescale of months to years. In silicate minerals, these timescales are of the order of thousands of years (Dove and Crerar, 1990; Ladd and Szymczak, 2021; Szymczak and Ladd, 2012; Zhu, 2005). Similarly, the characteristic timescale for the conduction processes in the confining rocks ( t C ) is commonly several orders of magnitude longer than the relaxation time for reactant transport ( t A ), which essentially maintains a steady state throughout the aquifer evolution. These timescales are given by

where l A and l C  are characteristic length scales of advection and heat conduction, respectively, u A denotes the characteristic Darcy flux [L T −1 ], α b  is the bulk thermal diffusivity, θ 0  represents the initial porosity, A s  stands for the specific surface area of the reacting mineral [L 2  L −3 ], and λ  is the kinetic reaction rate coefficient [L T −1 ]. Here, γ = Δ c s / c sol ν , where c sol  is the mineral concentration in the solid, ν  accounts for the stoichiometry of the reaction, and Δ c s is the variation in solubility induced by thermal changes along the flow path. Δ c s  is calculated here using the difference between the injected saturated fluid concentration, c ( φ = 0 ) = c s ( T in ) , and the downstream saturation at the background aquifer temperature, c = c s ( T 0 ) (i.e., Δ c s = | c s ( T in ) - c s ( T 0 ) | ). γ  is often referred to as the acid capacity number, representing the ratio between (I) under(super)-saturation created when cooling or heating the solution from T in to T 0 and (II) the number of molecules in a unit volume of a mineral,  c sol (see parameter values in Table 1; Ladd and Szymczak, 2017; Roded et al., 2020).

In the calculation of timescale  t A , the characteristic length scale,  l A , can be set to be equal to the reactive front length, which in turn is affected by the thermal front length along the aquifer ( φ direction). The length scale,  l C (used in t C  calculation) corresponds to the thermal front that develops in the confining insulating layers in the z direction, which elongates over time. In practice, the timescale separation between  t A and  t M and  t C can also be validated a posteriori. Under a large set of conditions, the reaction rate is limited solely by advective transport (i.e., regardless of kinetics), which leads to small geochemical disequilibrium (Andre and Rajaram, 2005). In such conditions, the actual timescale of matrix deformation will be much longer than predicted by the expression given above for  t M .

In this Appendix, the solution of Eq. (10) is compared to its approximated solution, when t ′ ≈ t is assumed (Fig. C1). The results demonstrate that for times longer than 100 years, the differences between the solutions diminish, with a maximal error of 1.5 %, where the error is defined as err = 100 ⋅ ( | T Ext - T Apr | ) / Δ T , with T Ext  and T Apr  being the exact and approximated solutions. These results confirm the validity of the assumption of t ′ ≈ t and the derived solutions for times longer than 100 years under the conditions considered.

Figure C1 Comparison of the full and approximate solution for the temperature profile. The approximate solution considers t ′ = t (Eq. 10). The results demonstrate that for times longer than 100 years, the differences between the solutions diminish, with a maximal error of 1.5 % (see text).

To obtain a solution by computational means and prevent an integer overflow (Press et al., 2007), it is useful to derive an approximate solution for Eq. (15) using the first-order asymptotic expansion of erf. Substituting this expansion into Eq. (15) leads to

and after further rearrangement, we finally arrive at

For the planar injection case, we obtain the following from Eq. (19):

To avoid integer overflow errors, Eq. (D2) is used to obtain the undersaturation profiles in Figs. 2b and 3a and is numerically iterated to solve for the porosity profile at later times ( t ≈100  kyr). The accuracy of the approximation of Eq. (D2) was verified by comparing it to the full solution in Eq. (15), which can be solved for early times ( t ≈1  yr). Furthermore, the accuracy of Eq. (D2) and the iterative solutions was further confirmed by solving for the porosity profile and comparing these results to those obtained using the full solution in Eq. (16) for t =10  kyr.

Using Darcy's law, we calculate an effective permeability,  k eff , for the aquifer around the well within a radius of r = R . The Darcy's law under these conditions is

where p  and μ  are the fluid pressure and viscosity and k  the permeability. Integrating Eq. (E1) between r =0 and r = R leads to

and the effective permeability is

which is calculated by numerical integration over the porosity profile and the power law given in Sect. 3.4.

The MATLAB codes and data produced in this study are available at https://doi.org/10.5281/zenodo.12531720 (Roded, 2024).

EA, RR, and PS: theoretical analysis. RR, EA, and PS: conceptualization. RR: numerical analysis and writing (original draft). RR, BL, and LED: geochemical modeling. RR, EA, LED, PS, MV, and BL: writing (review and editing).

The contact author has declared that none of the authors has any competing interests.

Publisher's note: Copernicus Publications remains neutral with regard to jurisdictional claims made in the text, published maps, institutional affiliations, or any other geographical representation in this paper. While Copernicus Publications makes every effort to include appropriate place names, the final responsibility lies with the authors.

This research has been supported by the Israel Science Foundation (ISF; grant no. 910/17 awarded to Einat Aharonov) and the National Science Centre (NCN, Poland) under CEUS-UNISONO grant no. 2020/02/Y/ST3/00121 awarded to Piotr Szymczak. The author thanks Atefeh Vafaie and an additional anonymous referee for their constructive comments.

This research has been supported by the Israel Science Foundation (grant no. 910/17) and the Polish National Science Centre (CEUS-UNISONO grant no. 2020/02/Y/ST3/00121).

This paper was edited by Alberto Guadagnini and reviewed by Atefeh Vafaie and one anonymous referee.

Abbasi, M., Khazali, N., and Sharifi, M.: Analytical model for convection-conduction heat transfer during water injection in fractured geothermal reservoirs with variable rock matrix block size, Geothermics, 69, 1–14, 2017. 

Agar, S. M. and Geiger, S.: Fundamental controls on fluid flow in carbonates: current workflows to emerging technologies, Geol. Soc. Lond. Spec. Publ., 406, 1–59, 2015. 

Aharonov, E., Whitehead, J. A., Kelemen, P. B., and Spiegelman, M.: Channeling instability of upwelling melt in the mantle, J. Geophys. Res.-Solid, 100, 20433, https://doi.org/10.1029/95JB01307 , 1995. 

Aharonov, E., Spiegelman, M., and Kelemen, P.: Three-dimensional flow and reaction in porous media: Implications for the Earth's mantle and sedimentary basins, J. Geophys. Res.-Solid, 102, 14821–14833, 1997. 

Aharonov, E., Tenthorey, E., and Scholz, C. H.: Precipitation sealing and diagenesis: 2. Theoretical analysis, J. Geophys. Res.-Solid, 103, 969–981, 1998. 

Al-Sulaimi, B.: The energy stability of Darcy thermosolutal convection with reaction, Int. J. Heat Mass Transf., 86, 369–376, 2015. 

Anderson, M. P., Woessner, W. W., and Hunt, R. J.: Applied groundwater modeling: simulation of flow and advective transport, Academic Press, ISBN 978-0-12-058103-0, 2015. 

Andre, B. J. and Rajaram, H.: Dissolution of limestone fractures by cooling waters: Early development of hypogene karst systems, Water Resour. Res., 41, W01015, https://doi.org/10.1029/2004WR003331 , 2005. 

Bear, J. and Cheng, A. H.-D.: Modeling groundwater flow and contaminant transport, Springer Science & Business Media, https://doi.org/10.1007/978-1-4020-6682-5 , 2010. 

Bekri, S., Thovert, J. F., and Adler, P. M.: Dissolution of porous media, Chem. Eng. Sci., 50, 2765–2791, 1995. 

Bhat, S. and Kovscek, A.: Permeability modification of diatomite during hot fluid injection, in: SPE Western Regional Meeting, Bakersfield, California, May 1998, https://doi.org/10.2118/46210-MS , 1998. 

Bonte, M., Stuyfzand, P. J., and Breukelen, B. M. van: Reactive transport modeling of thermal column experiments to investigate the impacts of aquifer thermal energy storage on groundwater quality, Environ. Sci. Technol., 48, 12099–12107, 2014. 

Budek, A. and Szymczak, P.: Network models of dissolution of porous media, Phys. Rev. E, 86, 056318, https://doi.org/10.1103/PhysRevE.86.056318 , 2012. 

Carroll, S., Mroczek, E., Alai, M., and Ebert, M.: Amorphous silica precipitation (60 to 120 °C): Comparison of laboratory and field rates, Geochim. Cosmochim. Ac., 62, 1379–1396, 1998. 

Chadam, J., Hoff, D., Merino, E., Ortoleva, P., and Sen, A.: Reactive infiltration instabilities, IMA J. Appl. Math., 36, 207–221, 1986. 

Chaudhuri, A., Rajaram, H., and Viswanathan, H.: Early-stage hypogene karstification in a mountain hydrologic system: A coupled thermohydrochemical model incorporating buoyant convection, Water Resour. Res., 49, 5880–5899, 2013. 

Chen, C. and Reddell, D. L.: Temperature distribution around a well during thermal injection and a graphical technique for evaluating aquifer thermal properties, Water Resour. Res., 19, 351–363, 1983. 

Corson, L. T. and Pritchard, D.: Thermosolutal convection in an evolving soluble porous medium, J. Fluid Mech., 832, 666–696, 2017. 

Coudrain-Ribstein, A., Gouze, P., and de Marsily, G.: Temperature-carbon dioxide partial pressure trends in confined aquifers, Chem. Geol., 145, 73–89, 1998. 

Craw, D.: Fluid flow at fault intersections in an active oblique collision zone, Southern Alps, New Zealand, J. Geochem. Explor., 69, 523–526, 2000. 

Daccord, G.: Chemical Dissolution of a Porous Medium by a Reactive Fluid, Phys. Rev. Lett., 58, 479–482, 1987. 

Dávila, G., Dalton, L., Crandall, D. M., Garing, C., Werth, C. J., and Druhan, J. L.: Reactive alteration of a Mt. Simon Sandstone due to CO 2 -rich brine displacement, Geochim. Cosmochim. Ac., 271, 227–247, https://doi.org/10.1016/j.gca.2019.12.015 , 2020. 

Deng, H. and Spycher, N.: Modeling reactive transport processes in fractures, Rev. Mineral. Geochem., 85, 49–74, 2019. 

Deng, H., Molins, S., Trebotich, D., Steefel, C., and DePaolo, D.: Pore-scale numerical investigation of the impacts of surface roughness: Upscaling of reaction rates in rough fractures, Geochim. Cosmochim. Ac., 239, 374–389, 2018. 

Detwiler, R. L. and Rajaram, H.: Predicting dissolution patterns in variable aperture fractures: Evaluation of an enhanced depth-averaged computational model, Water Resour. Res., 43, W04403, https://doi.org/10.1029/2006WR005147 , 2007. 

Diaz, A. R., Kaya, E., and Zarrouk, S. J.: Reinjection in geothermal fields- A worldwide review update, Renew. Sustain. Energ. Rev., 53, 105–162, 2016. 

Diersch, H.-J. and Kolditz, O.: Variable-density flow and transport in porous media: approaches and challenges, Adv. Water Resour., 25, 899–944, 2002. 

Dove, P. M. and Crerar, D. A.: Kinetics of quartz dissolution in electrolyte solutions using a hydrothermal mixed flow reactor, Geochim. Cosmochim. Ac., 54, 955–969, 1990. 

Dreybrodt, W.: Processes in karst systems: physics, chemistry, and geology, Springer Verlag, Berlin, New York, xii, 288 pp., https://doi.org/10.1007/978-3-642-83352-6 , 1988. 

Dreybrodt, W., Gabrovšek, F., and Romanov, D.: Processes of speleogenesis: A modeling approach, Carsologica, edited by: Gabrovšek, F., Založba ZRC, Ljubljana, 375 pp., ISBN 961-6500-91-0, 2005. 

Fleuchaus, P., Godschalk, B., Stober, I., and Blum, P.: Worldwide application of aquifer thermal energy storage – A review, Renew. Sustain. Energ. Rev., 94, 861–876, 2018. 

Frick, S., Regenspurg, S., Kranz, S., Milsch, H., Saadat, A., Francke, H., Brandt, W., and Huenges, E.: Geochemical and process engineering challenges for geothermal power generation, Chem. Ing. Tech., 83, 2093–2104, https://doi.org/10.1002/cite.201100131 , 2011. 

Garing, C., Gouze, P., Kassab, M., Riva, M., and Guadagnini, A.: Anti-correlated porosity–permeability changes during th e dissolution of carbonate rocks: experimental evidences and modeling, Transp. Porous Media, 107, 595–621, 2015. 

Glassley, W. E.: Geothermal energy: renewable energy and the environment, CRC Press, https://doi.org/10.1201/b17521 , 2014. 

Goldscheider, N., Mádl-Szőnyi, J., Erőss, A., and Schill, E.: Thermal water resources in carbonate rock aquifers, Hydrogeol. J., 18, 1303–1318, 2010. 

Golfier, F., Zarcone, C., Bazin, B., Lenormand, R., Lasseux, D., and Quintard, M.: On the ability of a Darcy-scale model to capture wormhole formation during the dissolution of a porous medium, J. Fluid Mech., 457, 213–254, 2002. 

Grodzki, P. and Szymczak, P.: Reactive-infiltration instability in radial geometry: From dissolution fingers to star patterns, Phys. Rev. E, 100, 033108, https://doi.org/10.1103/PhysRevE.100.033108 , 2019. 

Hao, Y., Smith, M., Sholokhova, Y., and Carroll, S.: CO 2 -induced dissolution of low permeability carbonates. Part II: Numerical modeling of experiments, Adv. Water Resour., 62, 388–408, 2013. 

Hoefner, M. L. and Fogler, H. S.: Pore evolution and channel formation during flow and reaction in porous media, AICHE J., 34, 45–54, 1988. 

Hommel, J., Coltman, E., and Class, H.: Porosity–permeability relations for evolving pore space: a review with a focus on (bio-) geochemically altered porous media, Transp. Porous Media, 124, 589–629, 2018. 

Huenges, E. and Ledru, P.: Geothermal energy systems: exploration, development, and utilization, John Wiley & Sons, https://doi.org/10.1002/9783527630479 , 2011. 

Huenges, E., Kohl, T., Kolditz, O., Bremer, J., Scheck-Wenderoth, M., and Vienken, T.: Geothermal energy systems: research perspective for domestic energy provision, Environ. Earth Sci., 70, 3927–3933, 2013. 

Hussaini, S. R. and Dvorkin, J.: Specific surface area versus porosity from digital images, J. Petrol. Sci. Eng., 196, 107773, https://doi.org/10.1016/j.petrol.2020.107773 , 2021. 

Jamtveit, B. and Yardley, B.: Fluid flow and transport in rocks: mechanisms and effects, Springer Science & Business Media, https://doi.org/10.1007/978-94-009-1533-6 , 1996. 

Ji, J., Song, X., Song, G., Xu, F., Shi, Y., Lv, Z., Li, S., and Yi, J.: Study on fracture evolution model of the enhanced geothermal system under thermal-hydraulic-chemical-deformation coupling, Energy, 269, 126604, https://doi.org/10.1016/j.energy.2022.126604 , 2023. 

Jones, G. D. and Xiao, Y.: Geothermal convection in the Tengiz carbonate platform, Kazakhstan: Reactive transport models of diagenesis and reservoir quality, AAPG Bull., 90, 1251–1272, 2006. 

Jupp, T. and Woods, A.: Thermally driven reaction fronts in porous media, J. Fluid Mech., 484, 329–346, 2003. 

Jupp, T. and Woods, A.: Reaction fronts in a porous medium following injection along a temperature gradient, J. Fluid Mech., 513, 343–361, 2004. 

Kalia, N. and Balakotaiah, V.: Modeling and analysis of wormhole formation in reactive dissolution of carbonate rocks, Chem. Eng. Sci., 62, 919–928, 2007. 

Kelemen, P. B., Whitehead, J. A., Aharonov, E., and Jordahl, K. A.: Experiments on flow focusing in soluble porous media, with applications to melt extraction from the mantle, J. Geophys. Res.-Solid, 100, 475–496, 1995. 

Kolditz, O., Shao, H., Wang, W., and Bauer, S.: Thermo-Hydro-Mechanical Chemical Processes in Fractured Porous Media: Modelling and Benchmarking, Springer, https://doi.org/10.1007/978-3-319-29224-3 , 2016. 

Ladd, A. J. and Szymczak, P.: Reactive Flows in Porous Media: Challenges in Theoretical and Numerical Methods, Annu. Rev. Chem. Biomol. Eng., 12, 543–571, https://doi.org/10.1146/annurev-chembioeng-092920-102703 , 2021. 

Ladd, A. J. C. and Szymczak, P.: Use and misuse of large-density asymptotics in the reaction-infiltration instability, Water Resour. Res., 53, 2419–2430, 2017. 

Lai, P., Moulton, K., and Krevor, S.: Pore-scale heterogeneity in the mineral distribution and reactive surface area of porous rocks, Chem. Geol., 411, 260–273, 2015. 

Lauwerier, H.: The transport of heat in an oil layer caused by the injection of hot fluid, Appl. Sci. Res. Sect. A, 5, 145–150, 1955. 

Lichtner, P. C.: The Quasi-Stationary State Approximation to Fluid/Rock Reaction: Local Equilibrium Revisited, in: Diffusion, Atomic Ordering, and Mass Transport: Selected Topics in Geochemistry, edited by: Ganguly, J., Springer US, New York, NY, 452–560, https://doi.org/10.1007/978-1-4613-9019-0_13 , 1991. 

Lin, Y., Hu, T., and Yeh, H.: Analytical model for heat transfer accounting for both conduction and dispersion in aquifers with a Robin-type boundary condition at the injection well, Water Resour. Res., 55, 7379–7399, 2019. 

Lu, P., Luo, P., Zhang, G., Zhang, S., and Zhu, C.: A mineral-water-gas interaction model of p CO 2 as a function of temperature in sedimentary basins, Chem. Geol., 558, 119868, https://doi.org/10.1016/j.chemgeo.2020.119868 , 2020. 

Lucia, F. J.: Carbonate reservoir characterization: An integrated approach, in 2nd Edn., Springer-Verlag, Berlin, Heidelberg, ISBN 978-3-540-72740-8, 2007. 

Maher, K., Steefel, C. I., DePaolo, D. J., and Viani, B. E.: The mineral dissolution rate conundrum: Insights from reactive transport modeling of U isotopes and pore fluid chemistry in marine sediments, Geochim. Cosmochim. Ac., 70, 337–363, 2006. 

Maliva, R. G.: Anthropogenic aquifer recharge: WSP methods in water resources evaluation series no. 5, Springer, https://doi.org/10.1007/978-3-030-11084-0 , 2019. 

MATLAB: Version R2022b, Natick Mass. MathWorks Inc, https://www.mathworks.com (last access: 6 Septeber 2023), 2022. 

Micklethwaite, S. and Cox, S. F.: Progressive fault triggering and fluid flow in aftershock domains: Examples from mineralized Archaean fault systems, Earth Planet. Sc. Lett., 250, 318–330, 2006. 

Mostaghimi, P., Blunt, M. J., and Bijeljic, B.: Computations of absolute permeability on micro-CT images, Math. Geosci., 45, 103–125, 2013. 

Narr, W. and Suppe, J.: Joint spacing in sedimentary rocks, J. Struct. Geol., 13, 1037–1048, 1991. 

Nield, D. A. and Bejan, A.: Convection in Porous Media, Springer, https://doi.org/10.1007/978-3-319-49562-0_4 , 2017. 

Niemi, A., Bear, J., and Bensabat, J.: Geological Storage of CO 2 in Deep Saline Formations, Springer, https://doi.org/10.1007/978-94-024-0996-3 , 2017. 

Noiriel, C.: Resolving Time-dependent Evolution of Pore-Scale Structure, Permeability and Reactivity using X-ray Microtomography, Rev. Miner. Geochem., 80, 247–285, 2015. 

Noiriel, C., Steefel, C. I., Yang, L., and Ajo-Franklin, J.: Upscaling calcium carbonate precipitation rates from pore to continuum scale, Chem. Geol., 318–319, 60–74, 2012. 

Olasolo, P., Juárez, M., Morales, M., and Liarte, I.: Enhanced geothermal systems (EGS): A review, Renew. Sustain. Energ. Rev., 56, 133–144, 2016. 

Ortoleva, P., Chadam, J., Merino, E., and Sen, A.: Geochemical self-organization II; the reactive-infiltration instability, Am. J. Sci., 287, 1008–1040, 1987. 

Pacheco, F. A. L. and Alencoão, A. M. P.: Role of fractures in weathering of solid rocks: narrowing the gap between laboratory and field weathering rates, J. Hydrol., 316, 248–265, 2006. 

Pacheco, F. A. L. and Van der Weijden, C. H.: Role of hydraulic diffusivity in the decrease of weathering rates over time, J. Hydrol., 512, 87–106, 2014. 

Palmer, A. N.: Origin and morphology of limestone caves, Geol. Soc. Am. Bull., 103, 1–21, 1991. 

Pandey, S., Chaudhuri, A., Rajaram, H., and Kelkar, S.: Fracture transmissivity evolution due to silica dissolution/precipitation during geothermal heat extraction, Geothermics, 57, 111–126, 2015. 

Pandey, S., Vishal, V., and Chaudhuri, A.: Geothermal reservoir modeling in a coupled thermo-hydro-mechanical-chemical approach: a review, Earth-Sci. Rev., 185, 1157–1169, 2018. 

Peng, C., Crawshaw, J. P., Maitland, G. C., and Trusler, J. P. M.: Kinetics of calcite dissolution in CO 2 -saturated water at temperatures between (323 and 373) K and pressures up to 13.8 MPa, Chem. Geol., 403, 74–85, 2015. 

Phillips, O. M.: Geological fluid dynamics: sub-surface flow and reactions, Cambridge University Press, https://doi.org/10.1017/CBO9780511807473 , 2009. 

Plummer, L. N., Wigley, T. M. L., and Parkhurst, D. L.: The kinetics of calcite dissolution in CO 2 -water systems at 5 degrees to 60 degrees C and 0.0 to 1.0 atm CO 2 , Am. J. Sci., 278, 179–216, https://doi.org/10.2475/ajs.278.2.179 , 1978. 

Possemiers, M., Huysmans, M., and Batelaan, O.: Influence of Aquifer Thermal Energy Storage on groundwater quality: A review illustrated by seven case studies from Belgium, J. Hydrol.: Reg. Stud., 2, 20–34, 2014. 

Press, W. H., Teukolsky, S. A., Vetterling, W. T., and Flannery, B. P.: Numerical recipes: The art of scientific computing, Cambridge University Press, ISBN 13 978-0-511-33555-6, 2007. 

Rawal, C. and Ghassemi, A.: A reactive thermo-poroelastic analysis of water injection into an enhanced geothermal reservoir, Geothermics, 50, 10–23, 2014. 

Regenauer-Lieb, K., Veveakis, M., Poulet, T., Wellmann, F., Karrech, A., Liu, J., Hauser, J., Schrank, C., Gaede, O., and Fusseis, F.: Multiscale coupling and multiphysics approaches in earth sciences: Applications, J. Coupl. Syst. Multisc. Dyn., 1, 281–323, 2013. 

Rimstidt, J. D. and Barnes, H.: The kinetics of silica-water reactions, Geochim. Cosmochim. Ac., 44, 1683–1699, 1980. 

Roded, R.: MATLAB codes and data compiled here, Zenodo [code] and [data set], https://doi.org/10.5281/zenodo.12531720 , 2024. 

Roded, R., Shalev, E., and Katoshevski, D.: Basal heat-flow and hydrothermal regime at the Golan-Ajloun hydrological basins, J. Hydrol., 476, 200–211, 2013. 

Roded, R., Paredes, X., and Holtzman, R.: Reactive transport under stress: Permeability evolution in deformable porous media, Earth Planet. Sc. Lett., 493, 198–207, 2018. 

Roded, R., Aharonov, E., Holtzman, R., and Szymczak, P.: Reactive flow and homogenization in anisotropic media, Water Resour. Res., 56, e2020WR027518, https://doi.org/10.1029/2020WR027518 , 2020. 

Roded, R., Szymczak, P., and Holtzman, R.: Wormholing in anisotropic media: Pore-scale effect on large-scale patterns, Geophys. Res. Lett., 48, e2021GL093659, https://doi.org/10.1029/2021GL093659 , 2021. 

Roded, R., Aharonov, E., Frumkin, A., Weber, N., Lazar, B., and Szymczak, P.: Cooling of hydrothermal fluids rich in carbon dioxide can create large karst cave systems in carbonate rocks, Commun. Earth Environ., 4, 465, https://doi.org/10.1038/s43247-023-01082-z , 2023. 

Sabo, M. S. and Beckingham, L. E.: Porosity-Permeability Evolution During Simultaneous Mineral Dissolution and Precipitation, Water Resour. Res., 57, e2020WR029072, https://doi.org/10.1029/2020WR029072 , 2021. 

Sahimi, M.: Flow and transport in porous media and fractured rock: from classical methods to modern approaches, John Wiley & Sons, https://doi.org/10.1002/9783527636693 , 2011. 

Sanford, W. E. and Konikow, L. F.: Simulation of calcite dissolution and porosity changes in saltwater mixing zones in coastal aquifers, Water Resour. Res., 25, 655–667, 1989. 

Scholz, C. H.: The mechanics of earthquakes and faulting, Cambridge University Press, https://doi.org/10.1017/9781316681473 , 2019. 

Seigneur, N., Mayer, K. U., and Steefel, C. I.: Reactive transport in evolving porous media, Rev. Mineral. Geochem., 85, 197–238, 2019. 

Shaw-Yang, Y. and Hund-Der, Y.: An analytical solution for modeling thermal energy transfer in a confined aquifer system, Hydrogeol. J., 16, 1507–1515, 2008. 

Spiegelman, M., Kelemen, P. B., and Aharonov, E.: Causes and consequences of flow organization during melt transport: The reaction infiltration instability in compactible media, J. Geophys. Res.-Solid, 106, 2061–2077, 2001. 

Stauffer, F., Bayer, P., Blum, P., Molina Giraldo, N., and Kinzelbach, W.: Thermal Use of Shallow Groundwater, 1st Edition, CRC Press, https://doi.org/10.1201/b16239 , 2013. 

Steefel, C. I., Molins, S., and Trebotich, D.: Pore scale processes associated with subsurface CO 2 injection and sequestration, Rev. Miner. Geochem., 77, 259–303, 2013. 

Steefel, C. I., Appelo, C. A. J., Arora, B., Jacques, D., Kalbacher, T., Kolditz, O., Lagneau, V., Lichtner, P. C., Mayer, K. U., and Meeussen, J. C. L.: Reactive transport codes for subsurface environmental simulation, Comput. Geosci., 19, 445–478, 2015. 

Szymczak, P. and Ladd, A. J. C.: Reactive-infiltration instabilities in rocks. Fracture dissolution, J. Fluid Mech., 702, 239–264, 2012. 

Taron, J. and Elsworth, D.: Thermal–hydrologic–mechanical–chemical processes in the evolution of engineered geothermal reservoirs, Int. J. Rock Mech. Min. Sci., 46, 855–864, 2009. 

Tripp, G. I. and Vearncombe, J. R.: Fault/fracture density and mineralization: a contouring method for targeting in gold exploration, J. Struct. Geol., 26, 1087–1108, 2004. 

Turcotte, D. L. and Schubert, G.: Geodynamics, Cambridge University Press, https://doi.org/10.1017/CBO9780511807442 , 2002. 

Tutolo, B. M., Kong, X.-Z., Seyfried Jr., W. E., and Saar, M. O.: High performance reactive transport simulations examining the effects of thermal, hydraulic, and chemical (THC) gradients on fluid injectivity at carbonate CCUS reservoir scales, Int. J. Greenh. Gas Con., 39, 285–301, https://doi.org/10.1016/j.ijggc.2015.05.026 , 2015. 

Vafaie, A., Cama, J., Soler, J. M., Kivi, I. R., and Vilarrasa, V.: Chemo-hydro-mechanical effects of CO 2 injection on reservoir and seal rocks: A review on laboratory experiments, Renew. Sustain. Energ. Rev., 178, 113270, https://doi.org/10.1016/j.rser.2023.113270 , 2023. 

Voigt, H. and Haefner, F.: Heat transfer in aquifers with finite caprock thickness during a thermal injection process, Water Resour. Res., 23, 2286–2292, 1987. 

White, M., Fu, P., McClure, M., Danko, G., Elsworth, D., Sonnenthal, E., Kelkar, S., and Podgorney, R.: A suite of benchmark and challenge problems for enhanced geothermal systems, Geomech. Geophys. Geo-Energ. Geo-Resour., 4, 79–117, 2018. 

Wood, J. R. and Hewett, T. A.: Reservoir diagenesis and convective fluid flow, AAPG Memoir., 37, 99–110, https://doi.org/10.1306/M37435C6 , 1984. 

Woods, A. W.: Flow in porous rocks, Cambridge University Press, https://doi.org/10.1017/CBO9781107588677 , 2015. 

Xu, L., Szymczak, P., Toussaint, R., Flekkøy, E. G., and Måløy, K. J.: Dissolution Phase Diagram in Radial Geometry, Front. Phys., 8, 369, https://doi.org/10.3389/fphy.2020.00369 , 2020.  

Yang, S.-Y., Yeh, H.-D., and Li, K.-Y.: Modelling transient temperature distribution for injecting hot water through a well to an aquifer thermal energy storage system, Geophys. J. Int., 183, 237–251, 2010. 

Yardley, B. W., Manning, C. E., and Garven, G.: Frontiers in geofluids, John Wiley & Sons, https://doi.org/10.1002/9781444394900 , 2011. 

Zheng, Y., Ross, A., Villholth, K. G., and Dillon, P.: Managing Aquifer Recharge. A Showcase for Resilience and Sustainability, UNESCO, Paris, ISBN 978-92-3-100488-9, 2021. 

Zhou, Q., Oldenburg, C. M., and Rutqvist, J.: Revisiting the analytical solutions of heat transport in fractured reservoirs using a generalized multirate memory function, Water Resour. Res., 55, 1405–1428, 2019. 

Zhu, C.: In situ feldspar dissolution rates in an aquifer, Geochim. Cosmochim. Ac., 69, 1435–1453, 2005. 

Ziagos, J. P. and Blackwell, D. D.: A model for the transient temperature effects of horizontal fluid flow in geothermal systems, J. Volcanol. Geoth. Res., 27, 371–397, 1986. 

• Introduction
• Mathematical analyses
• Thermally driven reactive flow in geothermal systems
• Summary and conclusions
• Appendix A:  An extended form of the conservation equations
• Appendix B:  Timescale analysis to validate the quasi-static assumption
• Appendix C:  Lauwerier solution validity assuming  t ′ ≈ t
• Appendix D:  Asymptotic expansion for the disequilibrium solutions
• Appendix E:  Permeability of an aquifer with non-uniform porosity profile
• Appendix F:  Nomenclature
• Code and data availability
• Author contributions
• Competing interests
• Acknowledgements
• Financial support
• Review statement