Expert opinion outranks evidence in practice guidelines issued by the Infectious Diseases Society of America. More than half of the roughly 4,200 recommendations--culled from 41 IDSA guidelines issued over the last 16 years--are based on the lowest level of evidence, report researchers from Drexel University.
So physicians following practice guidelines are not necessarily practicing evidence-based medicine, says MedPage Today.
The researchers ranked the recommendations based on three levels of strength and three levels of evidence quality. In the strength category, 43 percent were rated at the highest level. Among these, just 23 percent were supported by top-level evidence from at least one randomized clinical trial. Thirty-seven percent, by contrast, were supported by low-level evidence; they were based only on the opinions of authorities based on clinical experience, descriptive studies or reports of expert committees.
- here's the article