Evidence-Based Medicine is a relatively new movement that seeks to put clinical med- icine on a firmer scientific footing. I take it as uncontroversial that medical practice should be based on best evidence-the interesting questions concern the details. This paper tries to move towards a coherent and unified account of best evidence in medicine, by exploring in particular the EBM position on RCTs (randomized controlled trials).

Evidence-Based Medicine (EBM) developed from the work of clinical epidemiologists at McMaster University and Oxford University in the 1970s and 1980s and self-consciously presented itself as a "new paradigm" called "evidence-based medicine" in the early 1990s. The techniques of the randomized controlled trial, systematic review and meta-analysis have produced an extensive and powerful body of research. They have also generated a critical literature that raises general concerns about its methods. This paper is a systematic review of the critical literature. It (...) finds the description of EBM as a Kuhnian paradigm helpful and worth taking further. Three kinds of criticism are evaluated in detail: criticisms of procedural aspects of EBM (especially from Cartwright, Worrall and Howick), data showing the greater than expected fallibility of EBM (Ioaanidis and others), and concerns that EBM is incomplete as a philosophy of science (Ashcroft and others). The paper recommends a more instrumental or pragmatic approach to EBM, in which any ranking of evidence is done by reference to the actual, rather than the theoretically expected, reliability of results. Emphasis on EBM has eclipsed other necessary research methods in medicine. With the recent emphasis on translational medicine, we are seeing a restoration of the recognition that clinical research requires an engagement with basic theory (e.g. physiological, genetic, biochemical) and a range of empirical techniques such as bedside observation, laboratory and animal studies. EBM works best when used in this context. (shrink)

Within public health, and increasingly other areas of social policy, there are widespread calls to increase or improve the use of evidence for policy-making. Often these calls rest on an assumption that increased evidence utilisation will be a more efficient or effective means of achieving social goals. Yet a clear elucidation of what can be considered “good evidence” for policy is rarely articulated. Many of the current discussions of best practise in the health policy sector derive from the evidence-based medicine (...) movement, embracing the “hierarchy of evidence” that places experimental trials as pre-eminent in terms of methodological quality. However, a number of problems arise if these hierarchies are used to rank or prioritise policy relevance. Challenges in applying evidence hierarchies to policy questions arise from the fact that the EBM hierarchies rank evidence of intervention effect on a specified and limited number of outcomes. Previous authors have noted that evidence forms at the top of... (shrink)

The problem of collecting, analyzing and evaluating evidence on adverse drug reactions (ADRs) is an example of the more general class of epistemological problems related to scientific inference and prediction, as well as a central problem of the health-care practice. Philosophical discussions have critically analysed the methodological pitfalls and epistemological implications of evidence assessment in medicine, however they have mainly focused on evidence of treatment efficacy. Most of this work is devoted to statistical methods of causal inference with a special (...) attention to the privileged role assigned to randomized controlled trials in Evidence Based Medicine. Regardless of whether the RCT’s privilege holds for efficacy assessment, it is nevertheless important to make a distinction between causal inference of intended and unintended effects, in that the unknowns at stake are heterogonous in the two contexts. This point has been emphasized by epidemiologists in the last decade. Their main focus is methodological, and regards the fact that bias and confounding do not affect studies on intended and unintended effects in the same way. However, deeper concerns ground the intuition for such a distinction; these are related to the constraints which we impose on evidence and their epistemological justification. My thesis is that such constraints ought to be understood to be different in the case of evidence for risk vs. benefit assessment. I present the recent debate on the causal association between acetaminophen and asthma in order to illustrate the point at issue. (shrink)

Helen Longino seeks to break the current deadlock in the ongoing wars between philosophers of science and sociologists of science--academic battles founded on disagreement about the role of social forces in constructing scientific knowledge. While many philosophers of science downplay social forces, claiming that scientific knowledge is best considered as a product of cognitive processes, sociologists tend to argue that numerous noncognitive factors influence what scientists learn, how they package it, and how readily it is accepted. Underlying this disagreement, however, (...) is a common assumption that social forces are a source of bias and irrationality. Longino challenges this assumption, arguing that social interaction actually assists us in securing firm, rationally based knowledge. This important insight allows her to develop a durable and novel account of scientific knowledge that integrates the social and cognitive. Longino begins with a detailed discussion of a wide range of contemporary thinkers who write on scientific knowledge, clarifying the philosophical points at issue. She then critically analyzes the dichotomous understanding of the rational and the social that characterizes both sides of the science studies stalemate and the social account that she sees as necessary for an epistemology of science that includes the full spectrum of cognitive processes. Throughout, her account is responsive both to the normative uses of the term knowledge and to the social conditions in which scientific knowledge is produced. Building on ideas first advanced in her influential book Science as Social Knowledge, Longino brings her account into dialogue with current work in social epistemology and science studies and shows how her critical social approach can help solve a variety of stubborn problems. While the book focuses on epistemological concerns related to the sociality of inquiry, Longino also takes up its implications for scientific pluralism. The social approach, she concludes, best allows us to retain a meaningful concept of knowledge in the face of theoretical plurality and uncertainty. (shrink)

Casuistry and principlism are two of the leading contenders to be considered the methodology of bioethics. These methods may be incommensurable since the former emphasizes the examination of cases while the latter focuses on moral principles. Conversely, since both analyze cases in terms of mid-level principles, there is hope that these methods may be reconcilable or complementary. I analyze the role of principles in each and thereby show that these theories are virtually identical when interpreted in a certain light. That (...) is, if the gaps in each method are filled by a concept of judgment or Aristotelian practical wisdom, these methods converge. (shrink)

The claims of randomized controlled trials to be the gold standard rest on the fact that the ideal RCT is a deductive method: if the assumptions of the test are met, a positive result implies the appropriate causal conclusion. This is a feature that RCTs share with a variety of other methods, which thus have equal claim to being a gold standard. This article describes some of these other deductive methods and also some useful non-deductive methods, including the hypothetico-deductive method. (...) It argues that with all deductive methods, the benefit that the conclusions follow deductively in the ideal case comes with a great cost: narrowness of scope. This is an instance of the familiar trade-off between internal and external validity. RCTs have high internal validity but the formal methodology puts severe constraints on the assumptions a target population must meet to justify exporting a conclusion from the test population to the target. The article reviews one such set of assumptions to show the kind of knowledge required. The overall conclusion is that to draw causal inferences about a target population, which method is best depends case-by-case on what background knowledge we have or can come to obtain. There is no gold standard. (shrink)

This article examines the emergence of casuistical case analysis as a methodological alternative to more theory-driven approaches in bioethics research and education. Focusing on The Abuse of Casuistry by A. Jonsen and S. Toulmin, the article articulates the most characteristic features of this modernday casuistry (e.g., the priority allotted to case interpretation and analogical reasoning over abstract theory, the resemblance of casuistry to common law traditions, the ‘open texture’ of its principles, etc.) and discusses some problems with casuistry as an (...) ‘anti-theoretical’ method. It is argued that casuistry so defined is ‘theory modest’ rather than ‘theory free’ and that ethical theory can still play a significant role in casuistical analysis; that casuistical analyses will encounter conflicting ‘deep’ interpretations of our social practices and institutions, and are therefore unlikely sources of increased social consensus on controversial bioethical questions; that its conventionalism raises questions about casuistry's ability to criticize norms embedded in the societal consensus; and that casuistry's emphasis upon analogical reasoning may tend to reinforce the individualistic nature of much bioethical writing. It is concluded that, notwithstanding these problems, casuistry represents a promising alternative to the regnant model of ‘applied ethics’ (i.e., to the ritualistic invocation of the so-called ‘principles of bioethics’). The pedagogical implications of casuistry are addressed throughout the paper and include the following recommendations: (1) use real cases, (2) make them long, richly detailed and comprehensive, (3) present complex sequences of cases, (4) stress the problem of ‘moral diagnosis’, and (5) be ever mindful of the limits of casuistical analysis. Keywords: casuistry, interpretation, methodology, pedagogy CiteULike Connotea Del.icio.us What's this? (shrink)

Although cases are central to the epistemic practices utilized within clinical medicine, they appear to be limited in their ability to provide evidence about causal relations because they provide detailed accounts of particular patients without explicit filtering of those attributes most likely to be relevant for explaining the phenomena observed. This paper uses a series of recent case reports to explore the role of cases in casual attribution in medical diagnosis. It is argued that cases are brought together by practitioners (...) to generate causal attributions and testable predictions using a manipulability view of causation. (shrink)

The claims of RCTs to be the gold standard rest on the fact that the ideal RCT is a deductive method: if the assumptions of the test are met, a positive result implies the appropriate causal conclusion. This is a feature that RCTs share with a variety of other methods, which thus have equal claim to being a gold standard. This paper describes some of these other deductive methods and also some useful non-deductive methods, including the hypothetico-deductive method. It argues (...) that with all deductive methods, the benefit that the conclusions follow deductively in the ideal case comes with a great cost: narrowness of scope. This is an instance of the familiar trade-off between internal and external validity. RCTs have high internal validity but the formal methodology puts severe constraints on the assumptions a target population must meet to justify exporting a conclusion from the test population to the target. The paper reviews one such set of assumptions to show the kind of knowledge required. The overall conclusion is that to draw causal inferences about a target population, which method is best depends case-by-case on what background knowledge we have or can come to obtain. There is no gold standard. (shrink)

This essay focuses on how casuistry can become a useful technique of practical reasoning for the clinical ethicist or ethics consultant. Casuistry is defined, its relationship to rhetorical reasoning and its interpretation of cases, by employing three terms that, while they are not employed by the classical rhetoricians and casuists, conform, in a general way, to the features of their work. Those terms are (1) morphology, (2) taxonomy, (3) kinetics. The morphology of a case reveals the invariant structure of the (...) particular case whatever its contingent features, and also the invariant forms of argument relevant to any case of the same sort: these invariant features can be called topics. Taxonomy situates the instant case in a series of similar cases, allowing the similarities and differences between an instant case and a paradigm case to dictate the moral judgment about the instant case. This judgment is based, not merely on application of an ethical theory or principle, but upon the way in which circumstances and maxims appear in the morphology of the case itself and in comparison with other cases. Kinetics is an understanding of the way in which one case imparts a kind of moral movement to other cases, that is, different and sometimes unprecedented circumstances may move certain marginal or exceptional cases to the level of paradigm cases. In conclusion, casuistry is the exercise of prudential or practical reasoning in recognition of the relationship between maxims, circumstances and topics, as well as the relationship of paradigms to analogous cases. (shrink)