Sample sizes ranged from 2,372 (Netherlands) to 12,992 (New Zealand), with a total of 85,052 participating adults. Response rates range from a high value of 88% (Colombia) to a low value of 46% (France), with a weighted average response rate of 70%. As described in detail elsewhere [27], internal subsampling was used to reduce respondent burden by dividing the interview into two parts. All participants completed Part I, which included core standardised items to assess conditions of central interest, including whether the participant was a current or former tobacco smoker. Part II included standardised items about correlates and disorders of secondary interest. Part II was administered to an enriched subsample (n = 43,249) that included 100% of those who met criteria for any Part I disorder and a random subsample of approximately 25% of other Part I respondents. As alcohol and illicit drug use were assessed in Part II, the Part II sample is considered in this report. Part II cases were weighted by the inverse of their probability of selection in order to adjust for differential sampling. There was
