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. 2019 May 9;4(3):e001309. doi: 10.1136/bmjgh-2018-001309

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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.

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Flowchart describing the process of paper assessment in this systematic review. PRISMA, Preferred Reporting Items for Systematic Reviews and Meta-Analyses.