“…Of the 66 studies, 16 studies were restricted to low-risk patients [1,5,6,9,13,17,21,24,26,28,29,[31][32][33][34]41] and were thus included in this analysis. For these 16 studies, the number of studies that demonstrated low risk of bias was as follows: 13 (81%) for study participation, 14 (88%) for study attrition, 2 (13%) for confounding, and 7 (44%) for measurement of outcomes.…”