"Evidence based medicine is the conscientious, explicit, and judicious use of current best evidence in making decisions about the care of individual patients. The practice of evidence based medicine means integrating individual clinical expertise with the best available external clinical evidence from systematic research." (Sackett et al., 1996, p. 71).
Sackett, D.L., Rosenberg, W.M., Gray, J.A., Haynes, R.B., Richardson, W.S., 1996. Evidence-based medicine: What it is and what it isn’t. BMJ (Clinical Research Ed.), 312(7023), 71–2. http://dx.doi.org/10.1136/bmj.312.7023.71