Abstract
OBJECTIVES: The key economic evaluation (EE) databases, NHS EED and HEED, have closed. Which databases do we now need to search to identify economic evaluations for models and systematic reviews (SRs)? We assess which databases are now the best sources of EEs and whether typical search strategies are effective.
METHODS: A quasi-gold standard (QGS) set of economic evaluations was formed from studies included in SRs of EEs undertaken to inform HTA. 9 databases were searched for each QGS reference. Yield for each database, and combination of databases, was calculated. MEDLINE search strategies reported in source SRs were re-run to assess their performance in finding EEs.
RESULTS: We built a QGS of 351 records from 46 reviews. Embase had the highest yield (0.89), followed by Scopus (0.84) and MEDLINE and PubMed (both 0.81). The HTA database identified the highest number of unique records (13/351), despite a low overall yield (0.1). All 9 databases combined retrieved 337/351 records. The most efficient combination of databases which could be searched to find records for all 337 references was Embase, Scopus, HTA Database and (MEDLINE or PubMed). 10/29 (34.5%) of re-run strategies missed at least 1 of the included records available in MEDLINE (25 records missed in total). Only 1 of the missed records was due to failings of search terms used for the economics concept.
CONCLUSIONS: For most SRs Embase, HTA Database and either PubMed or MEDLINE are likely to be sufficient to identify EEs included in bibliographic databases. Additionally searching a multidisciplinary database may be useful, particularly in non-clinical topics. Beyond this, supplementary search techniques may be more efficient than extensive database searching. Weaknesses in reported MEDLINE search strategies were identified which impacted retrieval; these weaknesses appear to be associated with population and intervention concepts, rather than the economics concept.