Longitudinal effects of insufficient sleep on psychological problems among adolescent bullies based on Korean Child and Youth Panel Survey

This study was performed to investigate longitudinal effects of insufficient sleep on psychological problems among bullies and neutral students using the Korean Child and Youth Panel Survey (KCYPS) collected from 8th to 10th graders. At the first wave, 6.4% of students reported that they had bullied other students two or more times. Bullies having insufficient sleep duration at the first wave exhibited significantly higher aggression levels than bullies with sufficient sleep over time. Among neutral students, sleep insufficiency showed no longitudinal relationship with aggression. Our findings confirm that insufficient sleep was an associated factor for chronically elevated aggression among bullies.