Rigor: Many Guidelines For Heart Care Rely On Weak Evidence

Richard Harris:

Doctors turn to professional guidelines to help them identify the latest thinking on appropriate medical treatments, but a study out Friday finds that in the realm of heart disease, most of those guidelines aren’t based on the highest level of evidence.

A paper in JAMA, the journal of the American Medical Association, that was released online ahead of print, finds that less than 10 percent of cardiovascular guidelines are based on the most carefully conducted scientific studies, known as randomized controlled trials. A lot of the rest are based on much weaker evidence.

Renato Lopes, a cardiologist at Duke University and his colleagues decided to dig into the guidelines from the American College of Cardiology and the American Heart Association. The scientists also reviewed the European Society of Cardiology guidelines, and found a similar pattern.

Colleagues who had done a similar analysis a decade ago came up with a surprising and disappointing observation: Only 12.5 percent of these guidelines are based on the highest level of evidence.