Errors in search strategies used in systematic reviews and their effects on information retrieval




Systematic Reviews, Information Retrieval, Search Strategies


Objectives: Errors in search strategies negatively affect the quality and validity of systematic reviews. The primary objective of this study was to evaluate searches performed in MEDLINE/PubMed to identify errors and determine their effects on information retrieval.

Methods: A PubMed search was conducted using the systematic review filter to identify articles that were published in January of 2018. Systematic reviews or meta-analyses were selected from a systematic search for literature containing reproducible and explicit search strategies in MEDLINE/PubMed. Data were extracted from these studies related to ten types of errors and to the terms and phrases search modes.

Results: The study included 137 systematic reviews in which the number of search strategies containing some type of error was very high (92.7%). Errors that affected recall were the most frequent (78.1%), and the most common search errors involved missing terms in both natural language and controlled language and those related to Medical Subject Headings (MeSH) search terms and the non-retrieval of their more specific terms.

Conclusions: To improve the quality of searches and avoid errors, it is essential to plan the search strategy carefully, which includes consulting the MeSH database to identify the concepts and choose all appropriate terms, both descriptors and synonyms, and combining search techniques in the free-text and controlled-language fields, truncating the terms appropriately to retrieve all their variants.

Author Biographies

José Antonio Salvador-Oliván, Professor, Department of Library and Information Science and Faculty of Medicine, University of Zaragoza, Zaragoza

Professor, Department of Library and Information Science, University of Zaragoza, Spain.

MD. Professor. Faculty of Medicine. University of Zaragoza. Spain.

Gonzalo Marco-Cuenca, Professor, Department of Library and Information Science and Faculty of Medicine, University of Zaragoza, Zaragoza

Professor, Department of Library and Information Science, University of Zaragoza, Spain.

Professor. Faculty of Medicine. University of Zaragoza. Spain.

Rosario Arquero-Avilés, Professor, Department of Library and Information Science, University Complutense of Madrid, Madrid

Faculty of Library and Information Science. University Complutense of Madrid, Spain.


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Original Investigation