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Risk of bias of studies included in the meta-analysis. (a) Risk of bias summary: review of the authors’ own judgments about each risk of bias item for each included study. (b) Risk of bias graph: review the authors’ own judgments about each risk of bias item presented as percentages across all included studies. Figure generated by Cochrane Risk of Bias 2 (RoB 2) tool, [6,7,15,16,17,19,20,33,34,35,37,42,43,44,45,46,47,48,49].
