“…All were cohort studies, reporting original data [ 11 , 12 , 19 , 20 , 21 , 22 , 23 , 25 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 ]. Seven were prospective studies [ 12 , 25 , 30 , 37 , 48 , 49 , 50 ]. Nineteen were retrospective studies [ 19 , 21 , 22 , 23 , 28 , 29 , 31 , 32 , 33 , 34 , 35 , 38 , 39 , 40 , 43 , 44 …”