Evidence-based surgery

Surgical practice has been considered an art: ask 50 surgeons how to manage a patient and you will probably get 50 different answers. There is so much clinical information available that no surgeon can know it all. Evidence-based surgery is a move to find the best ways of managing patients using clinical evidence from collected studies. It was estimated that sufficient evidence to justify routine myocardial thrombolysis for heart attacks was available years before the ISIS studies which finally made it clinically acceptable. No one had gathered all the available information together. Centres such as the Cochrane Collaboration have been collecting randomised trials and reviews to provide up-to-date information for clinicians. The Cochrane Library presently includes a data­base of systematic reviews, reviews of surgical effectiveness and a register of controlled trials. It is expected that this will gradually smooth out the differences between clinicians as the best way of managing patients becomes more evident.

Collecting published evidence together and analysing it often requires reviews of multiple randomised trials. These meta­analyses involve complex statistical analyses designed to interpret multiple findings and synthesise the results of multiple studies.