These findings build upon prior analyses across important demographic groups. Schroeder and Moolchan (2007) found some measurement non-invariance in FTND across European and African ancestry participants, which we confirmed but further found the FTND to have only minor measurement non-invariance by sex and race (Johnson et al., 2008). Altogether, the prior and current findings increase confidence for researchers concluding comparisons made across birth cohorts using the FTND, as manifest scores have similar relations with an underlying dependence dimension regardless of birth cohort. Likewise, meta-analyses incorporating results from different birth cohorts are unlikely biased by non-invariance–induced heterogeneity. The FTND, therefore, provides a robust basis for comparing nicotine dependence across populations and informing public health research.
