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. 2021 Oct 19;18:14799731211041506. doi: 10.1177/14799731211041506

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© The Author(s) 2021

This article is distributed under the terms of the Creative Commons Attribution 4.0 License (https://creativecommons.org/licenses/by/4.0/) which permits any use, reproduction and distribution of the work without further permission provided the original work is attributed as specified on the SAGE and Open Access pages (https://us.sagepub.com/en-us/nam/open-access-at-sage).

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Figure 1. — Search and selection of studies for systematic review according to preferred reporting items for systematic reviews and meta-analyses (PRISMA).