Quality assessment of the included studies
The quality evaluation was conducted using the criteria of the Cochrane Collaboration tool for assessing the risk of bias in RCTs. All of the five included RCTs satisfied the required items, including random sequence generation, allocation concealment, blinding of the study participants and personnel, and blinding of outcome assessments [4–7,11]. The results of the publication quality assessment are shown in Figures 2 and 3.