In defense of expert opinion.

Evidence-based medicine, centered on the incorporation of evidence from clinical trials and systematic reviews into the teaching and practice of clinical medicine, explicitly attempts to supplant expert opinion, which is viewed as an antiquated and unreliable form of medical authority. The epistemology of evidence-based medicine categorizes expert opinion as the lowest form of medical evidence, superseded even by methodologically flawed clinical research. When derived from direct clinical experience, however, expert opinion represents an alternative form of medical knowledge, one that may be complementary to empirical evidence. Input from clinical experts is vital to informing the context of clinical research and an appeal to alternate forms of medical knowledge, including expert opinion, is necessary to overcome the intrinsic gap between clinical research and the care of individual patients. Even when the quality and quantity of empirical medical evidence are ideal, expert opinion will remain an integral part of the multifaceted knowledge required for the optimal practice of clinical medicine.