Which resources should be used to identify RCT/CCTs for systematic reviews: a systematic review

摘要: Systematic reviewers seek to comprehensively search for relevant studies and summarize these present the most valid estimate of intervention effectiveness. The more resources searched, higher yield, thus time costs required conduct a systematic review. While there is an abundance evidence suggest how extensive randomized controlled trials (RCTs) should be, it neither conclusive nor consistent. This review was conducted in order assess value different identify inclusion reviews. Seven electronic databases, four journals Cochrane Colloquia were searched. Key authors contacted references articles screened. Included compared two or sources find RCTs clinical (CCTs). A checklist developed applied quality reporting. Data extracted by one reviewer checked second. Medians ranges precision recall calculated; results grouped comparison. Meta-analysis not performed due large heterogeneity. Subgroup analyses for: strategy (Cochrane, Simple, Complex, Index), expertise searcher librarian, non-librarian), study design (RCT CCT). Sixty-four representing 13 databases met criteria. common comparisons MEDLINE vs. handsearching (n = 23), MEDLINE+handsearching 13), reference standard 13). Quality low, particularly reporting selection methodology. Overall, varied substantially comparison ranged from 0 100% 99%, respectively. trial registries best with median 89% (range 84, 95) 96.5% (96, 97), although are based on small number studies. Inadequate inappropriate indexing reason cited missing Complex strategies (SS) better than Simple SS. Multiple-source comprehensive searches necessary all review, needs be improved. Although demonstrated highest precision, SS consultation librarian recommended. Continued efforts develop CENTRAL supported.