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Risk of bias for each study [20,21,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43] using the revised Cochrane risk of bias tool for randomized trials. D1: Bias arising from the randomization process, D2: Bias due to deviations from intended interventions, D3: Bias due to missing outcome data, D4: Bias in measurement of the outcome, D5: Bias in selection of reported results.
