The Cochrane Collaboration. Preparing, maintaining, and disseminating systematic reviews of the effects of health care

WHERE SHOULD a physician look to find accurate, up-to-date information about the effectiveness of a variety of clinical interventions? At the bedside or in the office, physicians should have instantaneous, up-to-date assistance from an affordable, universally available database of systematic reviews of the best evidence from clinical trials. Unfortunately, the physician who tries to seek the best evidence is often thwarted. Textbooks and reviews are often unreliable and years out of date.1The searcher may find the MEDLINE database, surely one of the greatest achievements of US medicine, daunting and incomplete. Although well over 1 million clinical trials have been conducted, hundreds of thousands remain See also pp 1942 and 1962. unpublished or are hard to find and may be in various languages. In the unlikely event that the physician finds all the relevant trials of a treatment, these are rarely accompanied by any comprehensive systematic review attempting to