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. 2022 May 19;12(5):e059207. doi: 10.1136/bmjopen-2021-059207

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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 flow diagram summarising the review and reasons for article exclusion. *Full text articles and snowballed articles excluded for the following reasons. Note that some articles were excluded for multiple reasons. Reasons for article exclusion are below.