Have you seen our latest Insider's Insight on Case Reports? Once a staple of medical journals, the case report had, until recently, laid buried at the bottom, of the evidence-based medicine hierarchy, destined for a pauper’s grave. The age of ‘medical enlightenment’ in the form of the evidence-based medicine revolution placed its emphasis on the randomized controlled trial (RCT) and the data super-tanker, the meta-analysis. From the 1970s through the 1990s, research methodology expanded to include an ever more sophisticated array of techniques that we still use today, from ‘power calculations’ to the Holms-Bonferroni method. If you didn’t experience the deification of the RCT yourself there are plenty of accounts detailing the reasons for its rise in popularity, its strengths, and its limitations [1,2].

As with the RCT, the limitations and disadvantages of case reports have been well discussed and documented [3]. And pitfalls associated with the data recorded in case reports are many, including:

• Lack of generalisability to the wider patient population
• Inability to link cause with effect
• Potential for over interpretation of a single observation or even a case series linking several similar observations (the so-called anecdotal fallacy)
• Publication bias (medical journals have still not addressed their toxic addiction to limiting publication to positive findings) coupled with limited journal guidance on submission requirements [4]
• Focus on difficult to reproduce (rare) episodes
• Lack of relevance, with most cases being submitted by specialists focusing on rare presentations of conditions rarely seen in family medicine

In our most recent Insider’s Insight providing background and instruction on how to create winning articles. Over recent years the case report has risen again like a phoenix, as reflected in the number of medical journals exclusively dedicated to publishing case reports. As observed in the Bible (Book of Ecclesiastes), “there's nothing new under the sun,” or ironically by Chaucer, “There’s never a new fashion but it’s old.” Nowadays we might note “What goes around comes around.” The first international, PubMed-indexed medical journal publishing only case reports was launched in 2007 quickly followed by others [5,6]. Our summary of case reports details some of the many examples of new discoveries or advances that began with a chance ‘interesting’ observation first to appear in case report format, as in the discovery of the congenital abnormalities caused by thalidomide reported in The Lancet in 1961 [3].

Case reports still have a powerful impact on clinicians because they frequently present cases in narrative form that reflects the traditional patient note format – something they can easily connect with. The case report is the optimal approach by which unusual, uncontrolled observations about symptoms, clinical findings, the natural history of an illness, or the complications of treatments or interventions, for example, can be presented to the audience [3]. Fundamentally, case reports are a scientific tool that excels in reporting novelty and in stimulating hypothesis generation. Perhaps the key characteristic of case reports is their capacity to anchor novelty in the public record. Cometh the time, cometh the technology – where in the past obscure observations might have been consigned to haunting the zombie literature, never to re-emerge from ‘the stacks’, the ability to search the depths of the known literature (an ability that has tracked the same time period of the case report’s rehabilitation) means that long forgotten observations can continue to contribute to our understanding.

One specific area where case reports or case series are useful is when other research methods are not feasible; the narrative approach of case reports facilitates a clearer clinical appreciation and patient perspective (e.g. journals like BMJ Case Reports include descriptions of the patient’s journey). If survival is any measure of value; case reports (and it might otherwise be difficult to explain their endurance and recent resurgence), then case reports have deep clinical, scientific and educational value. Many physicians, especially those without years of specialisation, case reports are the gateway to clinical discovery (and possibly research) [7, 8].

Rehabilitation of the case report as a channel for communication has opened the floodgates on a new (ahem) form of scientific reporting by seasoned specialists to medical students. Cases can include unusual or unexpected presentations of commonly seen illnesses; new associations or variations in disease processes; presentations, diagnoses, or management of new or emerging diseases. Perhaps a option of interest for those working in the pharmaceutical industry is observations around unexpected events seen in the course of treating or observing a patient or a novel or useful approach to managing patients with complex chronic condition. Clearly every aspect of scientific endeavour offers an opportunity for discovery.

References

1. Riley D. Case reports in the era of clinical trials. Glob Adv Health Med 2013;2:10-1.
2. Yitschaky O, et al. Case report on trial: do you, doctor, swear to tell the truth, the whole truth and nothing but the truth? J Med Case Rep 2011;5:179-80.
3. Nissen T, Wynn R. The clinical case report: a review of its merits and limitations. BMC Res Notes 2014;7:264-71.
4. Sorinola O, Olufowobi O, Coomarasamy A, Khan KS. Instructions to authors for case reporting are limited: a review of a core journal list. BMC Med Educ 2004;4:4-9.
5. Kidd M, Hubbard C. Introducing Journal of Medical Case Reports. J Med Case Rep 2007;1:1.
6. Kidd MR, Saltman D. Case reports at the vanguard of 21st century medicine. J Med Case Rep 2012;6:156.
7. McWhinney IR. Assessing clinical discoveries. Ann Fam Med 2008;6(1):3.
8. Pimlott N, Upshur REG. From clinical observation to clinical discovery. The challenge for family medicine research. Can Fam Physician 2014;60:14-6 (Eng), 27-9 (Fr).