LITERATURE SEARCHING FOR RANDOMIZED CONTROLLED TRIALS USED IN COCHRANE REVIEWS: RAPID VERSUS EXHAUSTIVE SEARCHES

To analyze sources searched in Cochrane reviews, to determine the proportion of trials included in reviews that are indexed in major databases, and to compare the quality of these trials with those from other sources.

All new systematic reviews in the Cochrane Library, Issue1 2001, that were restricted to randomized controlled trials (RCTs) or quasi-RCTs were selected. The sources searched in the reviews were recorded, and the trials included were checked to see whether they were indexed in four major databases. Trials not indexed were checked to determine how they could be identified. The quality of trials found in major databases was compared with those found from other sources.