These results can be usefully compared to two recent modeling studies of the externalizing spectrum. In the Minnesota twin family study, Hicks et al. (2004) examined four disorders as indices of a genetic externalizing spectrum and found a pattern of loadings not dissimilar to those found in our sample: ASPD (+0.79), followed by AAD (+0.72), DAD (+0.59) and CD (+0.56). In a large male prisoner sample, Venables & Patrick (2012) compared various individual interview-based measures to the total phenotypic score of their extensive externalizing spectrum inventory (ESI). Their highest correlations (in order) were similar to those observed in our genetic analyses of the externalizing spectra: drug dependence, adult antisocial behavior and conduct disorder, followed by lower correlations with alcohol dependence and nicotine use disorder.
