Evidence-based medicine (EbM) is the conscientious, explicit and judicious use of the current best evidence in making decisions about the care of individual patients.
The practice of EbM means integrating individual clinical expertise and patient values and wishes with the best available external clinical evidence from systematic research.
Definition adapted from: Sackett, D.L., Rosenberg, W.M.C., Gray, J.A.M., Haynes, R.B:, Richardson, W.S. (1996). Evidence based medicine: what it is and what it isn't. BMJ, 312:71. Link.