“…The observational studies were classified using the ROBINS-E tool. Fourteen of the fifty-six included studies were rated as ‘low risk of bias’ [ 10 , 13 , 15 , 22 , 24 , 25 , 26 , 29 , 30 , 34 , 36 , 40 , 47 , 48 ], sixteen as ‘some concerns’ [ 8 , 9 , 11 , 14 , 17 , 19 , 32 , 39 , 44 , 49 , 52 , 53 , 54 , 55 , 56 , 67 ], twenty as ‘high risk’ [ 6 , 7 , 16 , 27 , 31 , 33 , 35 , 38 , 41 , 42 , 43 , 45 , 46 , 50 , 51 , 57 , 58 , 59 , 60 , 61 ], and five as ‘very high risk’ [ 62 , 63 , 64 ...…”