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A fundamental aim of any systematic review is that all relevant studies should be identified and considered for inclusion. Limitations with searching bibliographic databases led the Cochrane Collaboration to search journals by hand for reports of trials. This article presents the results of a 3-year project to identify and make accessible reports of randomized trials published in European general health care journals. Overall, 21,620 reports of controlled trials were identified from 119 journals from 16 countries. More than three quarters (76%) were published in U.K. or German journals. Only 3,640 (17%) reports were indexed in MEDLINE as controlled trials, and 6,554 (30%) were not indexed in MEDLINE at all. Bibliographic details for all reports are available by searching The Cochrane Controlled Trials Register in The Cochrane Library. This project has ensured that a large proportion of trial reports not previously identifiable has been made accessible to those preparing systematic reviews.

Handsearching of medical journals for randomised trials can be a worthwhile effort. Clinicians and patients will become better informed about the value of different treatment options and researchers will reduce their risk of performing trials that are unnecessary.