An evaluation of searching the German CCMed database for the production of systematic reviews.

ABSTRACT

OBJECTIVES: National databases may be useful sources in the production of a systematic review (SR). The aim of this study was to assess the potential benefit of a systematic search in the German database 'Current Contents Medizin' (CCMed). METHODS: The study was conducted on the basis of published SRs that included CCMed as a literature source. Eligible SRs were identified through a systematic search in medline, embase and The Cochrane Library. The websites of German Health Technology Assessment agencies were also screened. Citations of primary studies included as relevant in the SRs were extracted and then categorised. RESULTS: The search yielded 52 eligible SRs. A total of 1505 relevant citations were extracted. Seventy-seven of these articles were published in journals indexed in CCMed. Thirty-two of the 77 citations were indexed in CCMed, but only eight of the 32 were unique. Of these eight citations, seven were not identified by a systematic search, but by handsearching. Only one unique citation, an observational study, was identified in CCMed by a systematic search. CONCLUSIONS: In the production of SRs, a systematic search in CCMed identifies relevant studies only in exceptional cases. Therefore, the routine inclusion of this database in systematic searches does not appear meaningful.