Longitudinal trajectory classes and correlates of the Multidimensional Personality Questionnaire-triarchic psychopathy scales from adolescence to young adulthood

The present study examined longitudinal trajectory classes and correlates of triarchic psychopathy domains (boldness, meanness, and disinhibition) from age 16 to 22, leveraging Multidimensional Personality Questionnaire (MPQ)-based triarchic scales data gathered on a large community sample (<i>n</i>s ranging between 483 and 775 across waves) oversampled for parental substance use disorder (SUD). Growth mixture models were conducted to examine longitudinal trajectory classes for each domain, and their associations with environmental covariates (e.g., neighborhood disadvantage and parental SUD) and outcomes at age 22 (e.g., violent behavior, antisocial personality disorder, and an overall problem index capturing internalizing symptoms and social problems). For boldness, all participants fell in the same class showing relative stability over time. Comparable solutions were recovered for meanness and disinhibition (high-stable/increasing, mid-range decreasing, and low-decreasing). Links with external correlates supported well-known differences between boldness and both meanness and disinhibition and additionally revealed interesting differences between meanness and disinhibition, suggesting that environmental covariates better discriminated meanness trajectory classes. These results demonstrate considerable developmental heterogeneity in these traits across adolescence into young adulthood, which relates to outcomes associated with antisociality and general life struggles. Further, these findings support the adequacy of the MPQ as an operationalization tool for longitudinal investigations on psychopathy.