“…Ten studies [ 24 , 25 , 30 , 31 , 32 , 34 , 38 , 39 , 40 , 41 ] described the generation of a completely randomized sequence, and 6 studies [ 24 , 25 , 31 , 34 , 38 , 41 ] used a suitable allocation concealment method. Thirteen studies [ 25 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 ] described that participants signed an informed consent for the experiment so that participants were nonblinded, which is a common drawback of nondrug clinical trials. There were 9 studies [ 24 , 25 , 32 , 34 , 36 , 38 , 39 , 40 , 41 ] that were blinded to outcome evaluators.…”