“…The female/male sex ratio was 0.7 for the case-control studies. The subjects enrolled were hospitalised patients in 13 prevalence studies [ 46 , 48 , 50 , 53 , 54 , 57 , 64 , 67 , 71 , 76 , 78 – 80 ] and 3 analytical studies [ 47 , 49 , 74 ]. Non-hospitalised subjects had been studied in 18 prevalence studies [ 42 – 45 , 51 , 52 , 59 – 61 , 63 , 65 , 68 – 70 , 72 , 73 , 75 , 77 ] and 6 analytical studies [ 41 , 55 , 56 , 58 , 62 , 66 ].…”