“…34 samples were analysed, from 34 studies ( appendix p 3 ). 11 , 15 , 19 , 20 , 21 , 22 , 23 , 29 , 31 , 32 , 33 , 35 , 36 , 37 , 38 , 39 , 46 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 , 61 , 62 , 63 , 64 , 65 In the total sample of smokers, prevalence of smoking in people presenting with their first episode of psychosis was 0·57 (95% CI 0·52–0·62; p<0·0001). Between-sample heterogeneity was significant, with an I 2 of 88·0%.…”