Guidelines should reflect all knowledge, not just clinical trials

Over the past 20 years, evidence based medicine has had a substantial influence on clinical decision making throughout the developed world. It now underpins healthcare policy and the burgeoning industry of clinical guideline development. Two problems have resulted. Firstly, so called high level evidence is increasingly equated with strong recommendations; and secondly, evidence other than that derived from randomised controlled trials (RCTs) is seen as intrinsically less valuable or reliable.