2.4. | Quality assessment of studies
The risk of bias for RCTs in the included studies was performed using the Cochrane criteria [38]. The objects applied for the evaluation of any study were as follows: adequacy of sequence generation, allocation concealment, blinding addressing of dropouts (incomplete outcome data), selective outcome reporting, and other expected sources of bias. According to the Cochrane Handbook recommendation, studies were determining to low risk of bias, high risk of bias or unclear regarding any parameters (Table 1).