This study is a meta-analysis of 94 050 individuals from 43 data sets. Written informed consent was obtained from all the participants. Inclusion in the study required (1) reported number of CPD and (2) the availability of genotype data for rs16969968 or its proxy (rs1051730). All the participants were ever-smokers of European descent aged 25 years or older; within each sample, only unrelated individuals were included. The sample sizes for each of the studies included in this meta-analysis are listed in the Table. A brief description of each sample is provided in eAppendix 1 (http://www.archgenpsychiatry.com).
