Some would consider it synonymous with "proof", "fact" or "knowledge". Some define evidence as "grounds for belief".
In Evidence-Based Medicine examination of the totality of evidence, rather than by selecting a limited sample of evidence is the best method for pursuing the truth.
Not all evidence is equal, and a set of principles can identify more vs less trustworthy evidence.
Evidence is necessary but not sufficient. Clinical decision making requires the applicaiton of values and preferences.