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. 2021 Nov 5;6(11):e007433. doi: 10.1136/bmjgh-2021-007433

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© Author(s) (or their employer(s)) 2021. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.

This is an open access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited, appropriate credit is given, any changes made indicated, and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/.

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Flow diagram for assessment of eligible studies in the systematic review and meta-analysis. EPPI Centre (COVID-19: a living systematic map of the evidence) was consulted up to 31 March 2020 (available through https://eppi.ioe.ac.uk/COVID19_MAP/covid_map_v5.html).