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. 2021 Jun 17;14:2765–2773. doi: 10.2147/DMSO.S313873

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© 2021 Hajek et al.

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PRISMA flow chart. Note: Adapted from Moher D, Liberati A, Tetzlaff J, Altman DG, Group P. Preferred reporting items for systematic reviews and meta-analyses: the PRISMA statement. PLoS Med. 2009;6(7):e1000097.²⁵