Evidence-Based Medicine (EBM) or Evidence-Based Practice (EBP) involves a cycle of enquiry.
It begins with a patient dilemma, or problem. Then a question is asked.
The literature is searched to acquire information.
The results are appraised, then applied to the specific question and patient.
Source: Duke University Medical Center Library
Medical scientists and practitioners rank evidence in an hierarchy according to its quality.
The highest quality evidence is the systematic review. The lowest quality evidence is the editorials and expert opinion.
Reference: Evidence-Based Practice in the Health Sciences: Evidence-Based Nursing Tutorial,Information Services Department of the Library of the Health Sciences-Chicago, University of Illinois at Chicago. Creative Commons License