"Clinical practice guidelines are systematically developed statements to assist practitioner and patient decisions about appropriate health care for specific clinical circumstances" (Institute of Medicine, 1990). They define the role of specific diagnostic and treatment modalities in the diagnosis and management of patients. The statements contain recommendations that are based on evidence from a rigorous systematic review and synthesis of the published medical literature.
National Heart, Lung, and Blood Institute (US). Clinical guidelines on the identification, evaluation, and treatment of overweight and obesity in adults: the evidence report [Internet]. Bethesda (MD): National Institutes of Health (US), National Heart, Lung, and Blood Institute; 1998 Sep [cited 2013 Jan 17]. (NIH publication no.98-4083). Available from: http://www.nhlbi.nih.gov/guidelines/obesity/ob_gdlns.pdf