“…According to the Cochrane tool ( 19 ), in the definition branch, six studies had a low risk of bias ( 27 â 29 , 31 , 32 , 39 ), 18 studies had a moderate risk of bias ( 24 , 26 , 30 , 33 â 36 , 38 , 43 â 46 , 48 , 50 , 52 , 58 , 69 , 79 ), 38 had an important risk of bias ( 21 , 22 , 37 , 40 â 42 , 49 , 51 , 54 , 56 , 57 , 59 â 68 , 70 â 72 , 74 â 78 , 80 â 88 ), and two studies had a very important risk of bias ( 23 , 73 ). Nine studies were not assessable with the tool (protocols or qualitative/mixed methods studies) ( 13 , 25 , 47 , 53 , 89 â 93 ).…”