Examination of aggression and self-injury in children with autism spectrum disorders and serious behavioral problems.

This study identified subtypes of aggression in a sample of 206 children with autism spectrum disorder (ASD) who participated in 2 risperidone trials. The narratives were derived from a parent interview about each child's 2 most pressing problems. Five subtypes of aggression emerged: hot aggression only, cold aggression only, self-injurious behavior (SIB) only, aggression and SIB, and nonaggressive. All groups showed a high rate of positive response to risperidone with no differences across subtypes. These study findings extend understanding of aggression in ASD and may be useful to guide further study on biological mechanisms and individualized treatment in ASD.