Internalizing and externalizing problems in adolescent aggression perpetrators, victims, and perpetrator-victims.

The aims of this study were to examine the risks of internalizing and externalizing problems in aggression perpetrators, victims, and perpetrator-victims and their sex differences, and to examine the effects of the level of aggression involvement on internalizing and externalizing problems. Eight thousand eighty-five adolescents in Taiwan completed the questionnaires. The associations of aggression involvement and the level of aggression involvement with internalizing and externalizing problems were examined. Compared with the neutrals, pure aggression perpetrators and perpetrator-victims had higher risks for internalizing and externalizing problems and pure victims had higher risks for internalizing problems and theft. Differences in the risks for internalizing and externalizing problems were found among 3 groups with aggression involvement. Levels of aggression involvement increased the risks for some internalizing and externalizing problems. Sex differences were also found. Internalizing and externalizing problems need to be detected among adolescents involved in aggression, especially among perpetrator-victims, those with high levels of aggression involvements, and females.