Proponents of evidence-based medicine (EBM) provide the “hierarchy of evidence” as a criterion for judging the reliability of therapeutic decisions. EBM's hierarchy places randomized interventional studies (and systematic reviews of such studies) higher in the hierarchy than observational studies, unsystematic clinical experience, and basic science. Recent philosophical work has questioned whether EBM's special emphasis on evidence from randomized interventional studies can be justified. Following the critical literature, and in particular the work of John Worrall, I agree that many of the (...) arguments put forward by advocates of EBM do not justify the ambitious claims that are often made on behalf of randomization. However, in contrast to the recent philosophical work, I argue that a justification for EBM's hierarchy of evidence can be provided. The hierarchy should be viewed as a hierarchy of comparative internal validity. Although this justification is defensible, the claims that EBM's hierarchy substantiates when viewed in this way are considerably more circumscribed than some claims found in the EBM literature. (shrink)

Here I inquire into the status of the rules promulgated in the canonical pronouncements on human subjects research, such as the Declaration of Helsinki and the Belmont Report. The question is whether they are ethical rules or rules of policy. An ethical rule is supposed to accurately reflect the ethical fact (the fact that the action the rule prescribes is ethically obligatory), whereas rules of policy are implemented to achieve a goal. We should be skeptical, I argue, that the actions (...) prescribed by the rules are ethically obligatory, and consequently we should focus our attention on how to craft the rules so as to promote the legitimate goals of human subjects research. Unfortunately, this cannot be done without evidence about the likely effects of various candidate policies—evidence we currently lack. Therefore, we should take the rules as mere starting points, subject to revision as the evidence comes in. (shrink)