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. 2021 Oct 25;8:753088. doi: 10.3389/fmed.2021.753088

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Copyright © 2021 Wang, Chen, Hu and Shen.

This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.

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Study flow diagram. Records identified by database searching and from gray literature. Sixty-five articles met the criteria for full-text review, with 11 finally included in the meta-analysis.