The incremental utility of callous-unemotional traits and conduct problems in predicting aggression and bullying in a community sample of boys and girls.

The current study tested whether callous-unemotional (CU) traits explained unique variance in measures of aggression and bullying, and in measures assessing cognitive and affective correlates to aggression, when controlling for conduct problem severity. In a sample of 284 ethnically diverse students (ages 9 to 14 years), a self-report measure of CU traits did not explain unique variance in self-report measures of reactive aggression but did interact with conduct problems in predicting proactive aggression, with conduct problems being more strongly related to proactive aggression in students high on CU traits. Conduct problems were also more strongly related to peer-reports of bullying in girls high on CU traits. Further, CU traits were negatively related to behaviors that defend victims of bullying, independent of conduct problem severity. Finally, conduct problems were more strongly related to anger dysregulation in students low on CU traits, and conduct problems were more strongly related to positive expectations for aggressive behavior in girls high on CU traits. These findings provide support for the proposal to include CU traits as a specifier for the diagnosis of conduct disorder.