Appraisal of: "Arber M, Glanville J, Isojarvi J, Baragula E, Edwards M, Shaw A, Wood H. Which databases should be used to identify studies for systematic reviews of economic evaluations? Int J Technol Assess Health Care. 2018 Jan;34(6):547-54."
NHS EED and HEED, two key databases for retrieving health economics information, have closed. Based on this changed landscape, this article assesses which databases are now the best sources of information for retrieving economic evaluations to inform systematic reviews. The authors built a quasi-gold standard database of 351 records compiled from 46 systematic reviews of economic evaluations. Nine databases were searched for each record. Embase had the highest yield (89%), followed by Scopus (84%) and MEDLINE and PubMed (both 81%). The HTA database identified the highest number of unique citations (13/351). Embase also uniquely identified two conference abstracts, an important consideration if this type of material is eligible for inclusion in a review. All nine database combined retrieved 337/351 (96%) records. Searching a combination of Embase, the HTA database and either PubMed or MEDLINE identified 95% of the quasi-gold standard records (333/351). The authors concluded that searching additional database outside the core group may be inefficient because of limited incremental yield. Searchers should not rely on PubMed or MEDLINE alone. Searching a multi-disciplinary database may also be useful, especially for non-clinical or public health topics. The authors conclude that searchers should focus on developing suitable search strategies in these key databases to ensure high sensitivity and adequate precision. Supplementary search techniques such as grey literature searching may be more efficient than searching a larger number of databases, as 14/351 (4%) citations were not identified in any of the databases.
MEDLINE search strategies reported in source systematic reviews were also assessed. 10/29 (34.5%) of re-run search strategies missed at least one of the included records found in MEDLINE (with 25 citations missed in total). Weaknesses in the population or intervention concepts, rather than the economics concept, were identified as negatively impacting search retrieval.