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)

This essay explores the role of informal logicand its application in the context of currentdebates regarding evidence-based medicine. This aim is achieved through a discussion ofthe goals and objectives of evidence-basedmedicine and a review of the criticisms raisedagainst evidence-based medicine. Thecontributions to informal logic by StephenToulmin and Douglas Walton are explicated andtheir relevance for evidence-based medicine isdiscussed in relation to a common clinicalscenario: hypertension management. This essayconcludes with a discussion on the relationshipbetween clinical reasoning, rationality, andevidence. It is argued that (...) informal logic hasthe virtue of bringing explicitness to the roleof evidence in clinical reasoning, and bringssensitivity to understanding the role ofdialogical context in the need for evidence inclinical decision making. (shrink)

Philosophy of medicine encompasses a broad range of methodological approaches and theoretical perspectives—from the uses of statistical reasoning and probability theory in epidemiology and evidence-based medicine to questions about how to recognize the uniqueness of individual patients in medical humanities, person-centered care, and values-based practice; and from debates about causal ontology to questions of how to cultivate epistemic and moral virtue in practice. Apart from being different ways of thinking about medical practices, do (and should) these different philosophical approaches have (...) anything in common? Are they committed to incompatible assumptions about the nature of science and its relationship to experience, value, and the art of medicine, or are different approaches nonetheless complementary? The chapter examines the questions these different approaches and perspectives raise and considers why so many theorists of medicine seek to find a “base” or “center” for medicine—as though there is, or should be, some general conceptual thread linking the things we call “usual clinical practice” in the real world. It further considers whether there are alternative approaches to the philosophy of medicine, which do not embody this philosophical assumption; and it suggests that a key tool for evaluating approaches must be their ability to contribute something of genuine value to clinical medicine. (shrink)

Contesting that a debate on evidence-based health care has taken place, this article charts three paths to the future: continuing avoidance of debate by proponents of evidence-based medicine (EBM); conflict, which the EBM movement courts and critics have espoused, and dialogue. The last portal allows for integration, which would end the disagreement between EBM and its critics and make a debate unnecessary. In search of integration, I sketch a bridge whose construction requires not compromise but a win- win approach. The (...) bridge is a medicine of meaning (MOM). Consolidating multiple pillars of evidence to unify questions that are not necessarily the same for protagonists and critics of EBM, a MOM contends that the purpose or meaning of medicine is always healing and helping, and each party finds meaning in medicine by contributing to this common purpose in its own distinctive way. (shrink)