Evidence based medicine: a movement in crisis?

Abstract

Trisha Greenhalgh and colleagues argue that, although evidence based medicine has had many benefits, it has also had some negative unintended consequences. They offer a preliminary agenda for the movement’s renaissance, refocusing on providing useable evidence that can be combined with context and professional expertise so that individual patients get optimal treatment It is more than 20 years since the evidence based medicine working group announced a “new paradigm” for teaching and practising clinical medicine.1 Tradition, anecdote, and theoretical reasoning from basic sciences would be replaced by evidence from high quality randomised controlled trials and observational studies, in combination with clinical expertise and the needs and wishes of patients. Evidence based medicine quickly became an energetic intellectual community committed to making clinical practice more scientific and empirically grounded and thereby achieving safer, more consistent, and more cost effective care.2 Achievements included establishing the Cochrane Collaboration to collate and summarise evidence from clinical trials;3 setting methodological and publication standards for primary and secondary research;4 building national and international infrastructures for developing and updating clinical practice guidelines;5 developing resources and courses for teaching critical appraisal;6 and building the knowledge base for implementation and knowledge translation.7 From the outset, critics were concerned that the emphasis on experimental evidence could devalue basic sciences and the tacit knowledge that accumulates with clinical experience; they also questioned whether findings from average results in clinical studies could inform decisions about real patients, who seldom fit the textbook description of disease and differ from those included in research trials.8 But others argued that evidence based medicine, if practised knowledgably and compassionately, could accommodate basic scientific principles, the subtleties of clinical judgment, and the patient’s clinical and personal idiosyncrasies.1 Two decades of enthusiasm and funding have produced numerous successes for …