© 2013 by The Johns Hopkins University Press The Limits of Evidence-Based Medicine in Psychiatry Philip Thomas, Pat Bracken, and Sami Timimi Abstract: Evidence-based medicine (EBM) has de- livered major benefits in somatic medicine, but the situation is less clear in psychiatry. Recent empirical evidence in psychiatry (from within the tradition of EBM) contradicts the fundamental assumption of this approach: the belief that mental health problems, and treatments for them, are best framed in a technical idiom. EBM is essentially an attempt to identify the most successful technical interventions for discretely defined medical conditions. This effectively renders the non-technical, nonspecific aspects of care as being of secondary importance. In this paper, we first consider some of the empirical evidence that challenges this perspective. We look at depression in particular and the results of randomized, controlled trials investigat- ing the effectiveness of modern antidepressant drugs as well as studies looking at the benefits of different forms of psychotherapy. These empirical studies (carried out according to the logic of EBM) indicate that the nonspe- cific factors are actually of primary importance. To tease out the implications of this, we first consider the work of Thomas Kuhn, who described scientific progress in terms of revolutions and changing paradigms, and then turn to the philosophy of Merleau-Ponty to describe the limitations of scientific accounts of experience. We argue that nonspecific factors have dual significance. They can be seen as Kuhnian anomalies, observations from within the EBM paradigm that are difficult to reconcile with the currently dominant paradigm. At the same time, as Merleau-Ponty argues, they reveal the limitations of scientific knowledge about human beings. They show that culture and meaning play a central role in mental health practice. Keywords: Cognitive therapy, depression, evidence- based medicine, Merleau-Ponty, antidepressants, Thomas Kuhn. It has often been emphasised that psychiatry is still an ‘expertise’ and has not yet reached the status of a science. Science calls for systematic, conceptual thinking which can be communicated to others. Only in so far as psychopathology does this can it claim to be regarded as a science. What in psychiatry is just expertise and art can never be accurately formulated and can at best be mutually sensed by another colleague. It is therefore hardly a matter for textbooks and we should not expect to find it there. (Jaspers 1963, 2) T his quotation indicates that Jaspers was immersed in a major debate in nine- teenth century philosophy of science: the Methodenstreit. His dismissive comments about the ‘art’ of psychiatry set the tone for arguments that continue today. What methods are best suited for use in psychiatry? Those of the natural or the human sciences? Is psychiatry truly a sci- ence, or does its subject matter—the suffering human being—mean that we must rely on other approaches? The ascendancy of clinical neurosci-