Time Trends, Trajectories, and Demographic Predictors of Bullying: A Prospective Study in Korean Adolescents

To illustrate time trends and trajectories of bullying and identify demographic predictors of bullying. A prospective study of 1666 seventh- and eighth-grade students from two Korean middle schools was conducted between 2000 and 2001. Using the Korean-Peer Nomination Inventory, bullying was categorized into four groups: victim, perpetrator, victim-perpetrator, and neither. Only the prevalence of male victims significantly decreased over the course of the study. Most students uninvolved in bullying at baseline remained so over the study period. In all, 52–58% of baseline victims and perpetrators and 74% of victim-perpetrators continued to be involved in bullying. Significantly more boys were involved with bullying than girls; individual stability of bullying behavior did not differ by gender. Shorter, heavier boys and those from lower SES, whose fathers had lower educational levels or whose mothers had higher educational levels, as well as shorter girls from Seoul or non-intact families, were at an increased risk for bullying. Except for a modest decline in the number of male victims, participation in bullying (especially by victim-perpetrators) is stable over time. Along with disadvantaged background, distinct demographic profiles of bullying involvement by sex and bullying groups emerged, allowing early identification of bullying and targeting intervention and prevention.