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. 2019 May 24;9(5):e024444. doi: 10.1136/bmjopen-2018-024444

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© Author(s) (or their employer(s)) 2019. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.

This is an open access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited, appropriate credit is given, any changes made indicated, and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/.

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Preferred Reporting Items for Systematic Reviews and Meta-Analyses flow diagram for Cochrane review updates demonstrating the outcomes of the search process, and the inclusion of studies in the updated Cochrane systematic review and meta-analysis. CDSR, Cochrane Database of Systematic Reviews; CENTRAL, Central Register of Controlled Trials; CINAHL, Cumulative Index to Nursing and Allied Health Literature; DARE, Database of Abstracts of Reviews of Effects; LILACS, Latin American and Caribbean Health Sciences Literature; NHSEED, NHS Economic Evaluation Database; RCT, randomised controlled trial; VTE, venous thromboembolism.