In medicine, a case report is a detailed report of the symptoms, signs, diagnosis, treatment, and follow-up of an individual patient. Case reports may contain a demographic profile of the patient, but usually describe an unusual or novel occurrence. Some case reports also contain a literature review of other reported cases. Case reports are professional narratives that provide feedback on clinical practice guidelines and offer a framework for early signals of effectiveness, adverse events, and cost. They can be shared for medical, scientific, or educational purposes.
Types
Most case reports are on one of six topics:
An unexpected association between diseases or symptoms.
An unexpected event in the course of observing or treating a patient.
A case report is generally considered a type of anecdotal evidence. Given their intrinsic methodological limitations, including lack of statistical sampling, case reports are placed at the bottom of the hierarchy of clinical evidence, together with case series. Nevertheless, case reports do have genuinely useful roles in medical research and evidence-based medicine. In particular, they have facilitated recognition of new diseases and adverse effects of treatments. Case reports have a role in pharmacovigilance. They can also help understand the clinical spectrum of rare diseases as well as unusual presentations of common diseases. They can help generate study hypotheses, including plausible mechanisms of disease. Case reports may also have a role to play in guiding the personalization of treatments in clinical practice. Proponents of case reports have outlined some particular advantages of the format. Case reports and series have a high sensitivity for detecting novelty and therefore remain one of the cornerstones of medical progress; they provide many new ideas in medicine. Whereas randomized clinical trials usually only inspect one variable or very few variables, rarely reflecting the full picture of a complicated medical situation, the case report can detail many different aspects of the patient's medical situation. Because typical, unremarkable cases are less likely to be published, use of case reports as scientific evidence must take into account publication bias. Some case reports also contain an extensive review of the relevant literature on the topic at-hand. Reports adopting this sort of approach can be identified by terms such as a "case report and review of the literature". Reports containing broader active research such as this might be considered case studies in the true definition of the term. Case reports can also play a relevant role in medical education, providing a structure for case-based learning. A particular attraction of case reports is the possibility of quick publication, allowing them to act as a kind of rapid short communication between busy clinicians who may not have the time or resources to conduct large scale research.
Reporting guidelines
The quality of the scientific reporting of case reports is variable, and sub-optimal reporting hinders the use of case reports to inform research design or help guide clinical practice. In response to these issues, reporting guidelines are under development to facilitate greater transparency and completeness in the provision of relevant information for individual cases. The CARE guidelines include a reporting checklist that is listed on the EQUATOR Network, an international initiative aimed at promoting transparent and accurate reporting of health research studies to enhance the value and reliability of medical research literature. This 13-item checklist includes indications regarding the title, key words, abstract, introduction, patient information, clinical findings, timeline, diagnostic assessment, therapeutic interventions, follow-up and outcomes, discussion, patient perspective, and informed consent. An explanation and elaboration article was published in the Journal of Clinical Epidemiology in 2017.
Publishing
Many international journals publish case reports, but they restrict the number that appear in the print run because this has an adverse effect on the journal's impact factor. Case reports are often published online, and there is often still a requirement for a subscription to access them. However, an increasing number of journals are devoted to publishing case reports alone, most of which are open access. The first of these to start publishing, in 2001, was Grand Rounds. There are a number of websites that allow patients to submit and share their own patient case reports with other people. PatientsLikeMe and Treatment Report are two such sites.
Use of terminology outside science
The term is also used to describe non-scientific reports usually prepared for educational reasons.
