Quality and reporting of literature search strategies in

Quality and reporting of literature search strategies in systematic reviews published by London School of Hygiene & Tropical Medicine affiliated authors: an assessment using PRISMA, AMSTAR and PRESS criteria Jane Falconer User Support Services Librarian

Question Yes No N/A Electronic search strategy is described for at least one database 59. 8% 40. 2% 0% Synonyms are used? 47. 5% 48. 4% 4. 1% A controlled vocabulary is used? 30. 3% 66. 4% 3. 3% Terms are truncated? 10. 7% 84. 4% 4. 9% The search syntax is adapted to each database? 13. 1% 68. 9% 18. 0%

Methodology Literature Search Web of Science Core Content • Organisation = LSHTM • Title contains “systematic review” • Year = 2015 or 2016 Random Sample n = 44 Analysis 58 item data extraction form with criteria from • PRISMA • AMSTAR • PRESS

PRISMA reporting characteristics Names of databases unambiguously stated Supplier of databases unambiguously stated Start/end dates clearly stated to at least mm/yy accuracy Fully repeatable search for one database Fully repeatable search for all databases Language not limited, or rationale for limit provided 68% 18% 32% 82% 34% 66% 55% 45% 36% 64% 55% 45% 50% Yes No

AMSTAR appraisal criteria Were both keywords and thesaurus terms provided? 52% 48% Yes No

PRESS quality criteria – basic skills 58% 64% 24% 18% 33% 3% AND OR NOT ADJ NEAR SAME used effectively truncat* used effectiv* 70% 45% 15% 24% ((brackets used appropriately) AND effectively) Yes No Unclear Not used 27% 3% search includes appropriate synonyms OR alternative words OR other words OR substitutes

PRESS quality criteria – subject headings Are the subject headings relevant? Are all relevant subject headings included, including previous terms? 67% 24% Are subject headings chosen at correct level? Not too broad/too narrow? Are subject headings exploded where necessary? Are both subject headings and terms in free text used for each concept? 6%6% 21% 49% 58% 36% 30% 64% Yes No 6% 21% 9% 12% 21% 30% Unclear 6% Not used n = 33

Overall quality score No search strategy was published 45% 11 Showed serious flaws Major problems leading to lack of confidence in study validity 20 Minor problems unlikely to impact study validity No problems with reporting or search quality 10 25% Could not be assessed due to lack of information 7% 3 Good quality search, clearly reported

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References • Gómez-Sánchez, A. F. , et al. (2016). Evaluating the information retrieval quality and methodological accuracy of systematic reviews and meta-analysis on congenital malformations (2004 -2014). Paper presented at the 15 th EAHIL Conference, Seville, Spain. http: //www. bvsspa. es/eahil 2016/wpcontent/uploads/2016/05/G 4. pdf • CWTS (Centre for Science and Technology Studies) (2017) CWTS Leiden Ranking 2017. [website]. Leiden University, Netherlands. http: //www. leidenranking. com/ranking/2017/list • THE (2014) REF 2014 results: table of excellence. [website] https: //www. timeshighereducation. com/news/ref-2014 -results-table-of-excellence/2017590. article • Page, M. J. , et al. (2016). Epidemiology and Reporting Characteristics of Systematic Reviews of Biomedical Research: A Cross-Sectional Study. PLo. S Med, 13(5), e 1002028. doi: 10. 1371/journal. pmed. 1002028 • Sampson, M. , & Mc. Gowan, J. (2006). Errors in search strategies were identified by type and frequency. J Clin Epidemiol, 59(10), 1057 -1063. doi: 10. 1016/j. jclinepi. 2006. 01. 007 • Bullers, K. , et al. (2018). It takes longer than you think: librarian time spent on systematic review tasks. J Med Libr Assoc, 106(2), 198 -207. • Page, M. J. , & Moher, D. (2017). Evaluations of the uptake and impact of the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) Statement and extensions: a scoping review. Systematic Reviews, 6(1), 263. doi: 10. 1186/s 13643 -017 -0663 -8 • Mead, T. L. , & Richards, D. T. (1995). Librarian participation in meta-analysis projects. Bull Med Libr Assoc, 83(4), 461 -464. • Rethlefsen, M. L. , et al. (2015). Librarian co-authors correlated with higher quality reported search strategies in general internal medicine systematic reviews. J Clin Epidemiol, 68(6), 617 -626. All photographs from Pexels (https: //www. pexels. com) unless otherwise noted and distributed under a CC 0 license.

Jane Falconer jane. falconer@lshtm. ac. uk @falkie 71 ORCID: 0000 -0002 -7329 -0577