Partial Evidence in Medicine

Evidence plays a crucial role in scientific activity. In this chapter, we discuss this notion in the context of evidence-based approaches to medical research. Nancy Cartwright has correctly emphasized why randomized clinical trials (RCTs) are not the gold standard in medicine (see, e.g., Cartwright 2009, 2010; Cartwright and Hardie 2012; additional skepticism regarding the alleged epistemic superiority of RCTs can be found in Worrall (2002, 2007)). We develop an account of evidence that explains why RCTs are taken to be so central in several areas of medical research, even though they may fall short of being the gold standard after all. The account provided emphasizes the gradualist, partial nature of evidence gathering, and the uncertainty involved throughout the process of obtaining, assessing and applying evidence in clinical research. Orthodox theories of decision-making require that rational choice be governed by a neutrality norm to the effect that epistemic considerations should not be affected by value judgments. In particular, according to this norm, our considerations about what is likely to happen should not be influenced by the values assigned to particular states of affairs. We examine below to what extent this norm has been violated in randomized clinical trials. We focus on early termination of clinical trials AU1