Classification of the level of evidence in international guidelines for acute and chronic heart failure

Abstract

Over the centuries, medicine has evolved as a system of care dependent on magic and superstition, fashion, a large placebo effect, self-confident physicians, the fears of patients, and some astute observations. More recently, attempts have begun to put medical care on a more scientific basis by making observations on large numbers of patients to evolve rational constructs for why treatments are effective or fail and ultimately by putting theory and observation to the test in randomized controlled trials. It will be a long time before the science of medicine has eliminated, replaced, or endorsed the current practices and dogma of medical treatment, but a start must be made if future generations of patients are to avoid potentially unnecessary or harmful traditional treatments. Chronic aspirin therapy (1, 2, 3, 4), cosmetic angioplasty (5), and intravenous inotropic therapy (6,7) are just three examples of unproven and potentially wasteful or harmful interventions that are widely practiced due to the failure of doctors to understand the evidence presented to the