Students' and teachers' perceptions of aggressive behaviour in adolescents with intellectual disability and typically developing adolescents.

This study investigated aggressive behaviour in Serbian adolescents with intellectual disability (ID) compared to typically developing peers. The sample consisted of both male and female adolescents aged 12-18 years. One hundred of the adolescents had ID, and 348 adolescents did not have ID. The adolescents were asked to complete the Reactive-Proactive Aggression Questionnaire (RPQ), and their teachers provided ratings of aggression for the adolescents using the Children's Scale of Hostility and Aggression: Reactive-Proactive (C-SHARP). Results indicated that adolescents reported a higher prevalence of aggressive behaviour than their teachers. Reactive aggression was more prevalent than proactive aggression in both subsamples. In the subsample of adolescents with ID, there were no sex or age differences for aggression. However, in the normative subsample, boys and older adolescents scored significantly higher on aggression. According to adolescent self-reports the prevalence of aggression was higher in adolescents without ID, while teachers perceived aggressive behaviour to be more prevalent in adolescents with ID. Scientific and practical implications are discussed.