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Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).
Methodological quality graph. (A) Risk of bias graph: authors’ assessments about each risk of bias item presented as percentages of all included studies. (B): Risk of bias summary: authors’ assessments about each risk of bias item for each included study. “+”:.