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. 2022 Mar 11;12(3):e058187. doi: 10.1136/bmjopen-2021-058187

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© Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.

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Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) flow chart of the study identification process for systematic reviews and meta-analyses.