The development of overt aggression across adolescence: The role of temperamental and environmental risk factors and the contribution of overt aggression to the emergence of antisocial psychopathology

© 2020 Stephen Paul HalperinPurpose of the study: The research reported in this study aimed to model the stability and change in overt aggression in a community sample of Australian adolescents over six years, and to contribute to the development of a comprehensive etiological model of antisocial psychopathology. It examined the impact of sex, effortful control (a temperamental risk factor), callous and unemotional traits (a hypothesized primary factor associated with youth psychopathy) and conditional aversive parenting (an environmental risk factor) and their interactions, on latent trajectories of overt aggression. It was hypothesized that combinations of these risk factors will predict much of the variation in overt aggression across adolescence and that variation in overt aggression would predict features of Conduct Disorder and Antisocial Personality Disorder in early adulthood. Method: A risk-enriched community sample of 245 adolescents and their parents participated. Repeated measurement of overt aggression occurred at four time points using the Child Behaviour Checklist/6-18 and Youth Self Report, from early adolescence (mean age=12.4 years) to early adulthood (mean age= 18.9 years). At Time 1 self-report questionnaires were used to assess the individual difference factors, and an observational measure of parent-adolescent interactions were recorded. At Time 4, both semi structured interviews and questionnaires were used to assess antisocial psychopathology and the other dimensions examined. Latent growth curve modeling was used to examine the patterns of stability and change in overt aggression over time. Growth mixture modeling was then used to examine the relationships between the latent trajectories, the predictor covariates and the distal outcomes. Results: In the sample as whole, self-reported overt aggression remained stable across adolescence, while parent-reported overt aggression decreased slightly. Two trajectories (almost equal in size) of self-reported overt aggression were evident in the sample: a low and slightly increasing trajectory and a moderate to high, stable trajectory. Low effortful control was associated with the moderate-high trajectory, and while there was some evidence of an association between callous and unemotional trait and the moderate-high trajectory, this association was not significant in the final model. Neither sex nor conditional aversive parenting was found to predict trajectories of overt aggression. Moderate-high stable overt aggression across adolescence was found to be prospectively associated with higher levels of antisocial psychopathology in early adulthood. Conclusions: The findings reported in this study contribute to the understanding of the etiological factors involved in the persistence of overt aggression across adolescence. The findings suggest that low effortful control may be the most important individual difference factor contributing to the persistence of overt aggression in adolescence, and suggests that research examining the role of callous and unemotional traits should incorporate measures of normal temperament or personality. The absence of any sex differences in the current study suggests that persistent overt aggression in both male and female Australian children and adolescents is worthy of attention and treatment. The findings also have implications for the prevention, early intervention and treatment of overt aggression and antisocial psychopathology, in particular, the potential for adapting interventions based on temperamental differences, and targeting effortful control and its components in future prevention efforts