Examination of the Clinical Queries and Systematic Review "hedges'' in EMBASE and MEDLINE

Introduction - This investigation sought to determine whether the methodological search filters in place as Clinical Queries limits in OvidSP EMBASE and OvidSP MEDLINE had been modified from those written by Haynes et al. [1] and whether the translations of these in PubMed and EBSCO MEDLINE were reliable. The translated National Library of Medicine (NLM) Systematic Reviews hedges in place in OvidSP MEDLINE and EBSCO MEDLINE were also examined. Methods - Search queries were run using the Clinical Queries and Systematic Reviews hedges incorporated into OvidSP EMBASE, OvidSP MEDLINE, PubMed, and EBSCO MEDLINE to determine the reliability of these limits in comparison with the published hedge search strings. Results - Five of the OvidSP EMBASE Clinical Queries hedges produced results that were different from the published search strings. Three of the EBSCO MEDLINE and five of the PubMed translated Clinical Queries hedges yielded markedly different results (. 10% difference) than those obtained using the OvidSP MEDLINE hedge counterparts. The OvidSP MEDLINE Systematic Reviews subject subset hedge was found to have a major error, which has been corrected. Discussion - Translations of hedges to appropriate syntax for other database platforms may result in significantly different search results. The platform searched should ideally be the one for which the hedges were written and tested. Regardless, the hedges in place may not be the same as the published hedge search strings. Quality control place as limits are the same as those that have been published.