Writing a clinical case study on a patient follows a structured format that walks the reader through the patient’s story: who they are, what happened, how they were diagnosed, what treatment looked like, and what other clinicians can learn from the experience. Whether you’re preparing a case for a journal submission, a class assignment, or a conference presentation, the process involves selecting the right case, organizing it chronologically, protecting the patient’s identity, and connecting your findings to the broader medical literature.
What Makes a Case Worth Writing Up
Not every patient encounter warrants a formal case study. The cases that get published or earn strong marks in academic settings share a common trait: they teach something. The most commonly accepted reasons for writing up a case include an unexpected association between diseases or symptoms, an unusual presentation of a known disease, a rare adverse response to therapy, a novel treatment approach, or findings that challenge or support a current theory about how a disease works.
That said, a case doesn’t need to be one-in-a-million to be valuable. A case report can have a reasonable chance of publication even if the presentation isn’t entirely novel, as long as it’s authentic and carries educational value or leads to an incremental advance in clinical understanding. If you treated a patient whose course made you stop and think, or whose presentation confused the team before the diagnosis became clear, that diagnostic puzzle is often exactly what readers want to learn from.
The Standard Structure
Most clinical case studies follow a format outlined by the CARE (CAse REport) guidelines, a checklist originally developed to standardize case reporting across medical journals. The core sections are:
- Title: A concise description that names the condition and hints at what makes the case notable.
- Abstract: A brief summary of the case, usually 150 to 250 words, covering the key clinical details and the takeaway.
- Introduction: A short section explaining why this case is unique, with references to existing medical literature for context.
- Patient Information: De-identified demographics, the patient’s primary concerns and symptoms, and relevant medical, family, and psychosocial history.
- Clinical Findings: Significant findings from the physical examination.
- Timeline: A chronological overview of the episode of care, often presented as a figure or table.
- Diagnostic Assessment: The methods used (lab tests, imaging, surveys), any diagnostic challenges encountered, and the final diagnosis along with other diagnoses that were considered.
- Therapeutic Intervention: What treatment was given and how it was administered.
- Follow-up and Outcomes: How the patient responded, any complications, and their status at the end of the reporting period.
- Discussion: An analysis connecting this case to the existing literature, explaining what it adds to clinical knowledge.
- Conclusion: One or more “take-away” lessons from the case.
You don’t need to use every section for every case. Academic assignments may condense or combine some of these. But for journal submissions, the CARE checklist is the gold standard, and many journals explicitly require it.
Writing the Case Presentation
The case presentation is the heart of your report, and it should read chronologically. According to the American College of Physicians, the recommended flow moves through history, physical examination, investigations, and then the hospital or clinical course. Think of it as telling the patient’s story in the order it actually unfolded.
Start with the patient’s age, sex, and relevant background, then describe what brought them in. Present the physical exam findings next, followed by the results of any testing. When listing lab work or imaging, lead with the abnormal findings that matter to the case. You can note that routine labs were normal in a single sentence rather than listing every value. The goal is to give the reader enough information to follow your clinical reasoning without burying them in irrelevant data.
For the timeline, a simple table works well. List dates (or relative timepoints like “Day 1,” “Week 3”) in one column and the corresponding clinical events in the other. This helps readers quickly grasp how the case evolved, especially when the course was complex or stretched over months. The CARE guidelines specifically recommend presenting historical and current information as a visual timeline whenever possible.
The Discussion Section
The discussion is where your case study shifts from storytelling to analysis. This is the section where you explain why the case matters in the context of what’s already known. Start by briefly summarizing the key features of your case, then compare them to similar cases in the published literature. Where does your case align with what’s expected? Where does it diverge?
If there were diagnostic challenges, walk the reader through your reasoning. Explain which diagnoses you considered and why you ruled them out. This kind of transparency is one of the most valuable parts of a case study because it mirrors the real-world thought process that other clinicians will face with similar patients. End the discussion by identifying the limitations of your report. A single case can’t prove causation or establish treatment guidelines, and acknowledging that strengthens your credibility rather than weakening it.
Protecting Patient Identity
Every patient case study requires de-identification, and the rules are more specific than most people realize. Under HIPAA’s Safe Harbor method, you must remove 18 categories of identifying information. These include the patient’s name, any geographic detail smaller than a state (street address, city, ZIP code), all date elements except year (birth date, admission date, discharge date), phone and fax numbers, email addresses, Social Security numbers, medical record numbers, health plan numbers, account numbers, license or certificate numbers, vehicle identifiers, device serial numbers, URLs, IP addresses, biometric identifiers like fingerprints, full-face photographs, and any other unique identifying code.
A few nuances are worth noting. For dates, you can include the year but not the month or day. For age, anyone over 89 must be listed simply as “90 or older” rather than their exact age. For ZIP codes, you can include only the first three digits, and only if that three-digit area contains more than 20,000 people. These rules apply regardless of whether you’re publishing in a journal or submitting for a class. Getting de-identification wrong is one of the most common and most serious mistakes in case report writing.
Getting Informed Consent
Before writing up any patient’s case, you need their written informed consent. This is separate from the consent they gave for treatment. The consent form should explain that their case will be described in a written report, specify where it will be published or presented, and confirm that identifying information has been removed. Most journals require you to include a statement in your manuscript confirming that consent was obtained.
If the patient is a minor, consent must come from a parent or legal guardian. For research conducted under certain federal regulations, both parents need to give permission unless one parent is deceased, unknown, legally incompetent, or not reasonably available. If the patient has died or lacks the capacity to consent, a legally authorized representative can provide permission on their behalf. Your institution’s review board can guide you on which forms to use and whether your case report requires formal ethical review.
Choosing Where to Submit
If you’re aiming for publication, journal selection matters. A 2016 survey identified around 160 journals that accepted case reports. That list has since grown to over 1,028 journals covering 129 specialties, compiled and available on the Open Science Framework. Some major journals no longer accept case reports in their flagship publications but have launched dedicated companion journals for them. The Journal of the American College of Cardiology, for instance, directs case reports to JACC Case Reports rather than other JACC titles.
Specialty-specific case report journals tend to have higher acceptance rates and faster turnaround times than broad general medicine journals. The Journal of Medical Case Reports and BioMed Central Research Notes are two well-known open-access options that publish across disciplines. Before submitting anywhere, check the journal’s author guidelines for word count limits, reference caps, and whether they require the CARE checklist to be submitted alongside your manuscript.
Common Mistakes to Avoid
The most frequent problems with patient case studies come down to structure and focus. Including too much irrelevant clinical detail, like a full list of normal lab values or a lengthy social history that doesn’t connect to the diagnosis, dilutes the case. Every piece of information you include should either advance the clinical narrative or support your discussion.
Another common error is a weak discussion section that simply restates the case instead of analyzing it. The discussion should do real intellectual work: compare your case to published literature, address why certain diagnoses were considered and rejected, and clearly state what this case adds to clinical knowledge. A third pitfall is failing to organize the case chronologically, which forces readers to piece together the timeline themselves. If the sequence of events was complicated, a timeline table isn’t optional; it’s essential.