In 1990, the Institute of Medicine proposed guideline development to reduce inappropriate health care variation by assisting patient and practitioner decisions.1 Unfortunately, too many current guidelines have become marketing and opinion-based pieces, delivering directive rather than assistive statements.
Current use of the term guideline has strayed far from the original intent of the Institute of Medicine. Most current articles called “guidelines” are actually expert consensus reports. It is not surprising, then, that the article by Tricoci et al2 in this issue of JAMA demonstrates that revisions of the American College of Cardiology (ACC)/American Heart Association (AHA) guidelines have shifted to more class II recommendations (conflicting evidence and/or divergence of opinion about the usefulness/efficacy of a procedure or treatment) and that 48% of the time, these recommendations are based on the lowest level of evidence (level C: expert opinion, case studies, or standards of care). This trend is especially disconcerting given the quantity of cardiovascular scientific literature published during the last decade.