Evidence-based medicine.

Clinical practice guidelines are an important product of the National Committee to Advise on Tropical Medicine and Travel (CATMAT). Recent guidelines have been published on the guiding principles for clinical practice guidelines. The ninth principle states: "Clinical practice guidelines should: (a) cite the specific evidence bearing upon the conclusion, (b) indicate the strength of the evidence [and] (c) specify the date of the most recent evidence considered." The following is CATMAT's statement on evidence-based medicine and the scales used to grade its recommendations.