In sum, the results provide good support for the two-factor (Detachment-Antisocial) Minnesota Temperament Inventory (MTI) model and the invariance of the item-to-factor relations in this model across adolescence into young adulthood. Furthermore, the MTI Detachment and Antisocial factors showed moderate to strong stability across time, and were associated with family and externalizing factors at late adolescence. We recommend future longitudinal studies of psychopathic traits employ similar SEM-based approaches to estimate the patterns of stability and change in psychopathic traits over time. Additionally, the current study examined a critical period in the life-course of personality development (Roberts & Mroczek, 2008). Furthermore, given that this is one of the first studies in the psychopathy literature to examine cross-lagged effects, we encourage future efforts to estimate the within- and across-time relations between correlated psychopathic trait domains (e.g., Interpersonal, Affective, Impulsive Lifestyle, overt Antisocial), as well as explore whether other external correlates relevant to the expression of psychopathic traits during adolescence (e.g., peer relations; Munoz, Kerr, & Besic, 2008) may moderate the course of antisocial and other psychopathic tendencies during the transition into adulthood.
