British Academy: The UK's National Academy for the Humanities and Social Sciences
Enquiry, Evidence and Facts: An Interdisciplinary Conference
The Role of the Case in the EBM Era: Evidence, Warrant, and Practice in Contemporary Medicine
Professor Rachel A. Ankeny,
School of History & Politics, The University of Adelaide, Napier 423,
Adelaide 5005 SA, Australia
An abstract presented to the conference
‘Enquiry, Evidence and Facts: An Interdisciplinary conference’
at the British Academy, London, on 13 December 2007
Biography
Rachel A. Ankeny has a BA in Liberal Arts, MA degrees in Philosophy, Bioethics, and Gastronomy, and a PhD in the History and Philosophy of Science (HPS). Prior to joining the University of Adelaide in 2006 as senior lecturer, she was director and lecturer/senior lecturer in the Unit for HPS at the University of Sydney from 2000. In HPS, her research focuses on the roles of models and case-based reasoning in science, model organisms, the philosophy of medicine, and the history of contemporary life sciences. Her research in bioethics examines ethical and policy issues in genetics, reproduction, women’s health, and embryo and stem cell research, among other topics. She serves as Treasurer of the History of Science Society, on several editorial boards for scholarly journals in HPS and bioethics, as associate editor of the Journal of the History of Biology, and as a faculty associate of the ‘Facts’ project at LSE.
Abstract
Cases, whether individual case reports or even case series, recently have been described as the “lowest form of intellectual life” (Vandenbroucke 1999). Due to their focus on individual patients, they typically are thought to be unscientific, anecdotal, and clearly inferior to other forms of evidence. Case studies and medical anecdotes have traditionally been held in disrepute, a trend which is associated with the historical shift away from single cases to more scientific, reductionistic explanations of disease (Hunter 1986). In recent times this tendency has been strengthened by the increasing popularity of evidence-based medicine (EBM), which itself represents a turn away from the rationalism of the 19th century which considered individual cases as worthy of examination using existing principles and theories.
Despite these trends, the case report still is exceedingly popular: it is estimated that 40,000 new case report publications are entered into the Medline database each year, with the core 120 clinical journals on average having 13.5% of their references devoted to case reports (Rosselli & Otero 2002). In most of these journals, there are very specific guidelines for what must be presented in a case report and what warrants reporting. For instance although The Lancet had a long history of publishing case reports, it began a peer-reviewed section in 1995 which was aimed at allowing clinicians an outlet for publication with a particular focus on reports that have a “striking message” (Bignall & Horton 1995). The overwhelming majority of case reports depict complaints arising in specialty or subspeciality settings, and describe uncommon or even ‘unique’ clinical occurrences (McCarthy & Reilly 2000). A good case study “begets awareness, jogs the memory and aids understanding” (Morgan 1985), a description which indicates the mixture of educative and epistemologic goals inherent in cases.
Thus it is clear that medicine has a notoriously complex and conflicted relationship with regard to its use of cases and their epistemic status. On the one hand, case studies and reports, and at the extreme, so-called ‘syndrome’ letters or pedagogical anecdotes (see Hunter 1986, 1990) remain essential ways of providing information about particular clinical phenomena, usually as observed in a single or a few individuals under uncontrolled circumstances (Simpson & Griggs 1985). They allow practitioners to recognize similar patterns as new patients present themselves, and to expand their background knowledge beyond their experiences of the typical or the usual in the clinic. On the other hand, single cases are seen as problematic in as much as they are deviations even from the norm of what is abnormal, as it were. They capture exceptions rather than rules, and heighten practitioners’ awareness that their field is in fact a ‘science of particulars’ (to use the term coined by Gorovitz & Macintyre 1976), or even as often claimed, an art rather than a science.
This paper presents a series of examples in order to develop a typology of circumstances where cases serve productive purposes even if we accept many of the principles of EBM. I reflect more generally on why our typical views of medical science and practice and of EBM cause us to overlook these key examples of cases and case-based reasoning as a form of evidence.
References
Bignall J. and Horton R. Learning from stories—The Lancet’s case reports. The Lancet 346: 1246, 1995.
Gorovitz S. and MacIntyre A. Toward a theory of medical fallibility. Journal of Medicine and Philosophy 1: 51–71, 1976.
Hunter K.M. ‘There was this one guy…’: the uses of anecdotes in medicine. Perspectives in Biology and Medicine 29: 619–630, 1986.
Hunter K.M. An n of 1: syndrome letters in The New England Journal of Medicine. Perspectives in Biology and Medicine 33: 237–251, 1990.
McCarthy L.H. and Reilly K.E. How to write a case report. Family Medicine 32: 190–195, 2000.
Morgan P.P. Why case reports? (editorial) Canadian Medical Association Journal 133: 353, 1985.
Rosselli D. and Otero A. The case report is far from dead (letter). The Lancet 359: 84, 2002.
Simpson R.J. and Griggs T.R. Case reports and medical progress. Perspectives in Biology and Medicine 28: 402–406, 1985.
Vandenbroucke J.P. Case reports in an evidence-based world. Journal of the Royal Society of Medicine 92: 159–163, 1999.