This paper explores some of the important parallels between recent reforms to legal rules for the admissibility of scientific and expert evidence, exemplified by the US Supreme Court's decision in Daubert v Merrell Dow Pharmaceuticals, Inc. in 1993, and similar calls for reforms to medical practice, that emerged around the same time as part of the Evidence-Based Medicine (EBM) movement. Similarities between the “movements” can be observed in that both emerged from a historical context where the quality of medicine and (...) legal approaches to science were being subjected to growing criticism, and in the ways that proponents of both movements have used appeals to “folk epistemologies” of science to help legitimate their reform aspirations. The term folk epistemology is used to describe the weaving together of formal and informal images of scientific method with normative and pragmatic concerns such as eradicating “junk science”, and promoting medical best practice. Perhaps unsurprisingly, given the unfocused breadth of these aspirations the implications of these “reforms” for medical and legal practice have not been straightforward, although they do represent an important new set of rhetorical resources to critique and or legitimate expertise in medical and legal domains. Discussion closes, by noting the growth of calls for these movements to reciprocate in areas where law and medicine intersect, such as medical negligence litigation. (shrink)

Hierarchies of evidence are an important and influential tool for appraising evidence in medicine. In recent years, hierarchies have been formally adopted by organizations including the Cochrane Collaboration [1], NICE [2,3], the WHO [4], the US Preventive Services Task Force [5], and the Australian NHMRC [6,7]. The development of such hierarchies has been regarded as a central part of Evidence-Based Medicine, a movement within healthcare which prioritises the use of epidemiological evidence such as that provided by Randomised Controlled Trials. Philosophical (...) work on the methodology of medicine has so far mostly focused on claims about the superiority of RCTs, and hence has largely neglected the questions of what hierarchies are, what assumptions they require, and how they affect clinical practice. This thesis shows that there is great variation in the hierarchies defended and in the interpretations they are, and can be, given. The interpretative assumptions made in using hierarchies are crucial to the content and defensibility of the underlying philosophical commitments concerning evidence and medical practice. Once this variation is been identified, it becomes clear that the little philosophical work that has been done so far affects only some hierarchies, under some interpretations. Modest interpretations offered by La Caze [11], conditional hierarchies like GRADE [12-14], and heuristic approaches such as that defended by Howick et al. [15,16] all survive previous philosophical criticism. This thesis extends previous criticisms by arguing that modest interpretations are so weak as to be unhelpful for clinical practice; that GRADE and similar conditional models omit clinically relevant information, such as information about variation in treatments’ effects and the causes of different responses to therapy; and that heuristic approaches lack the necessary empirical support. The conclusion is that hierarchies in general embed untenable philosophical assumptions: principally that information about average treatment effects backed by high-quality evidence can justify strong recommendations, and that the impact of evidence from individual studies can and should be appraised in isolation. Hierarchies are a poor basis for the application of evidence in clinical practice. The Evidence-Based Medicine movement should move beyond them and explore alternative tools for appraising the overall evidence for therapeutic claims. (shrink)