What is a case report?
Medical case reports are typically about a rare condition, a novel treatment, or an observation that has not been described before. Typically, there are few human studies available, and more data are needed to substantiate or extend our current understanding. Here we explain how to write a medical case report.
Why case reports are important?
Case reports provide valuable information that cannot be studied in a large cohort, due to the rarity of the condition. Therefore, when clinicians come across a rare condition, treatment, or observation, it is difficult to find human studies in the literature.
Journal expectations for case reports
Not all journals publish case reports. Some only publish them online. Some publish them as a letter or short report. Most journals have strict requirements for case reports. Therefore, when writing a case report, is important to adhere to all the journal’s guidelines, especially the word limits.
The subject of a case reports
Case reports typically describe one patient, but they can include a small number of cases.
When you want to describe more than about four cases, you should consider reporting it as a case series. Case series have a small number of patients, typically 5 to 10 patients. In a case series, in addition to the novel observations, you should point out the common features among the patients. However, the small number of patients precludes statistics or risk calculations.
The purpose of a case report
There are three main types of case reports:
- A description of the features or course of a rare condition – for example:
- This study aimed to contribute information to the small pool of data currently available.
- The purpose of this study is to describe a unique feature (or course) that has not been reported previously.
- A new treatment approach for a rare condition – for example:
- The purpose of this study was to describe a new (or alternative) treatment that might be more appropriate than the conventional treatment for X.
- This study aimed to describe an intervention that might be more appropriate than the conventional treatments in patients with X that also have Y.
- A new diagnostic method for a rare condition – for example:
- The purpose of this study was to describe a new diagnostic approach that could facilitate the detection of X in patients with mild or indeterminate symptoms.
- This study describes a more appropriate diagnostic method for differentiating X from other conditions with similar features.
How to organize a case report
Case reports are meant to be short. Therefore, they typically do not include the methods or results sections. Otherwise, the organization is similar to an original study. Start with the abstract, then include the introduction for background, a case report section to describe the case, and a discussion/conclusion section. See our blog on case reports here for more detailed information.
How to write an abstract for a case report
The abstract of a case report is typically shorter than abstracts for original studies and reviews. Therefore, it is important to highlight the central message of the study.
Some journals require a structured abstract, and they typically give you the headings for the structure. For example, background, case description, conclusion. Other journals require an unstructured abstract (i.e., no headings). In either case, you should include the following information, in the following order (the headings are only for structured abstracts):
(Purpose/Background)
- Describe the rarity of the disease/condition
- Give the purpose of the study (see above)
(Case description)
- Briefly give the patient’s age, the duration of the disease/condition, and its severity (i.e., the disease stage or degree of deterioration)
- Describe the main features/course, treatment, or diagnosis; this should be related to the study purpose
- Indicate the outcome
(Conclusion)
- Summarize the main finding; this should be related to the purpose of the study
- Indicate the clinical significance of the study (i.e., the central message)
How to write the introduction for a case report
The introduction should be brief. It should provide just enough background to understand why the case report is important. Include the following points:
- Describe the disease or condition and emphasize its rarity.
- Briefly indicate what is currently known and cite the corresponding reports.
- Describe the knowledge gap (i.e., missing information) that this study addresses.
- Explain how that information could advance the field, improve treatment, or facilitate diagnosis.
- End the introduction with the purpose (aim) of the current case report.
How to write the case description
The case description is the main part of a case report. Be sure to highlight the unique aspects of the case.
- Start with the age and sex of the patient and the main complaint (and duration) that led to the visit to your department.
- Give the case history, including previous diagnoses related to your study and any previous procedures, diagnoses, or conditions that could be important to the present observations.
- Describe the condition, including the stage of progression or the severity
- Explain the examinations performed for the workup.
- Give the diagnosis or suspected diagnosis, based on your examination/workup
- Describe the treatment and/or the monitoring method
- Describe the salient observations and/or outcome of treatment
- Indicate the current status of the patient
How to write the discussion/conclusion for a case report
The discussion/conclusion section should be brief, but it should use the space to emphasize what can be learned from the study.
- State the main finding and relate it to the study purpose
- Describe any uncertainties or hypotheses associated with the study
- Compare your results to other studies or alternative approaches, with citations
- State what you learned from the study (central message)
- Suggest further studies
Patient confidentiality
In case reports, it is important to keep all information on patient identity confidential. Thus, any photographs should be carefully clipped to remove any identifying features. Typically, a black bar across the eyes is insufficient. In most cases, full facial or full body photographs are not necessary. A representative photograph of the lesion could be sufficient to complement the text description.
Moreover, X-ray, computed tomography, ultrasound, and magnetic resonance images should be clipped to remove any labels that indicate dates, names, initials, etc. In fact, it is best to remove all data generated by the software to avoid distraction. The views, patient positions, weighting, and contrast methods should be described in the figure legend.
When it is important to show the spread or the affected areas on the body, consider making a generic drawing of a human being and indicating the affected areas on the body. For more detail, photographs of different stages or different types of lesions can be shown separately, and these types of lesions can be color-coded on the drawing.
Be aware that some journals require a statement that the patient provided informed consent to publish the data.
