Ad. Oxman et al., EVIDENCE-BASED CARE .2. SETTING GUIDELINES - HOW SHOULD WE MANAGE THIS PROBLEM, CMAJ. Canadian Medical Association journal, 150(9), 1994, pp. 1417-1423
There are four steps in determining how to manage a clinical problem.
The first is to formulate questions that are answerable; the second is
to locate and synthesize the evidence needed to answer the questions;
the third is to estimate the expected benefits, harms and costs of ea
ch option based on the evidence; and the fourth is to judge the relati
ve value of the expected outcomes to conclude whether the benefits are
worth the harms and costs. It is impractical to repeat these steps fo
r every clinical decision. Therefore, implicitly or explicitly, physic
ians rely on guidelines, ''rules'' that simplify decision making about
complex problems. If the methods used to develop a guideline are not
explicit it is difficult or impossible to know how much confidence to
place in it. Therefore, for common and important clinical problems, ph
ysicians should rely on guidelines that are systematically developed u
sing explicit methods.