A single, higher-order factor captured persistent involvement in externalizing behaviors and personality across emerging adulthood (ages 18 to 28). We tested for measurement invariance by biological sex and found that the model could be constrained to be equal across the sexes. Importantly, our model is largely consistent with a recent factor analytic examination of externalizing behavior in a genetic context (Latendresse et al., 2015). We extended the best-fitting model design (a bi-factor model) used by Latendresse and colleagues into a longitudinal framework, and included measures of hazardous alcohol use, cannabis use, property crime, tobacco use, and risky sex, as well as individual differences in sensation seeking and impulsive personality traits. Our phenotypic approach is also similar to that of an examination of polygenic risk for externalizing symptomology as captured by the first principal component extracted from a composite of clinical symptomology for externalizing disorders (Salvatore et al., 2015). However, our structured model allows for estimation of both common variance across the dimensions and unique domain-specific residual variances.
