The philosophical limits of evidence-based medicine.

Evidence-based medicine (EBM) has already had a profound effect on both medical education and clinical practice. The benefits of EBM, which defines the value of medical interventions in terms of empirical evidence from clinical trials, are enormous and well described. Not clearly acknowledged, however, are the limits of EBM. An intrinsic gap exists between clinical research and clinical practice. Failure to recognize and account for this gap may lead to unintended and untoward consequences. Under the current understanding of EBM, the individuality of patients tends to be devalued, the focus of clinical practice is subtly shifted away from the care of individuals toward the care of populations, and the complex nature of sound clinical judgment is not fully appreciated. Despite its promise, EBM currently fails to provide an adequate account of optimal medical practice. A broader understanding of medical knowledge and reasoning is necessary.