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. 2022 Feb 22;12(2):e054417. doi: 10.1136/bmjopen-2021-054417

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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 diagram. *The original PRISMA flow diagram indicated the number of studies included in meta-analysis in this box. This has been revised for the purposes of this research.