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. 2020 Feb 21;8(3):E313–E325. doi: 10.1055/a-1073-7593

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Fig. 1 — Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) flow diagram. From: Moher D, Liberati A, Tetzlaff J, Altman DG, The PRISMA Group (2009). Preferred Reporting Items for Systematic Reviews and Meta-Analyses: The PRISMA Statement. PLoS Med 6(7): e1000097. doi:10.1371/journal.pmed1000097