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. 2022 Feb 10;7(1):e000915. doi: 10.1136/bmjophth-2021-000915

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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 a Systematic Review and Meta-analysis flow diagram for transparent reporting of study selection process and meta-analysis.