Study objective: Although the Cochrane Library is promoted as a rigorous source of evidence, the relevance of this evidence to the out-of-hospital setting has not been assessed. The objective of this study is to identify existing controlled trials and systematic reviews in the Cochrane Library that have been conducted in or are relevant to out-of-hospital health care. The scope of out-of-hospital care, the years and trends of out-of-hospital research publication, and the journals of publication are also examined.
Methods: Using a search strategy developed by the Cochrane Prehospital and Emergency Health Field, 2 reviewers searched issue 4, 2005 of the Cochrane Library to identify reports of controlled trials and systematic reviews on out-of-hospital interventions. Three independent reviewers screened the titles identified by the search strategy and applied predetermined criteria to classify the reported study as out-of-hospital based or not out-of-hospital based. The out-of-hospital-based studies were then categorized as randomized or nonrandomized trials.
Results: Screening of the 19,759 titles retrieved by the search strategy identified 4,016 studies that were potentially out-of-hospital based. Abstract and full-text analysis of the 4,016 studies identified 400 reports of trials and 13 reviews or protocols that were out-of-hospital based. Of the 400 reports of trials identified, 299 (75%) were randomized trials. The number of out-of-hospital trials published increased steadily from the 1970s to the late 1990s, with the majority of trials (63%) covering interventions related to resuscitation and cardiac care. Annals of Emergency Medicine published more out-of-hospital trials than any other journal, followed by Resuscitation and Journal of the American Medical Association.
Conclusion: The Cochrane Library provides a useful resource of health care evidence; however, the relatively small number of out-of-hospital-based systematic reviews and trials does not comprehensively cover the broad scope of out-of-hospital health care.