Evidence based guidelines - a step too far?

The growth of clinical guidelines has helped to improve the standard of patient care with the archetypal document being the British Thoracic Society's guidelines on asthma management. In recent Years however the fashion has evolved to style guidelines according to the tenants of 'evidence based medicine'. We examine the evidence behind this fashion and conclude that there is a grave danger of bias and distortion of the data from this approach. (c) 2005 Elsevier Ltd. All rights reserved.