Descriptive statistics.

This study examines whether the experience of being bullied at school has a long-term impact on three health outcomes in adulthood in Japan: subjective health, mental health, and activity restriction due to health conditions. We employed a random effects model and the Karlson-Holm-Breen method to decompose the total effect of being bullied at school on health inequality into a direct effect and an indirect effect working through intervening factors including education, marriage, economic well-being, and social networks. We used the Japanese Life Course Panel Surveys 2007–2020 (waves 1–14), a nationally representative panel data set that includes 2,260 male and 2,608 female respondents. The results demonstrate that for both men and women, the direct effect of being bullied at school was strong and significant. Bullying experiences in childhood had a long-term impact on health outcomes in adulthood, regardless of social background and mediating factors of education, marriage, economic well-being, and social networks. Bullying victimization increased the risk of poor subjective health, low mental health scores, and activity restriction due to health conditions. Intervening factors (especially economic well-being and friendship) mediated the association between bullying experiences and all health outcomes, but their contributions were modest. Policy measures not only to prevent bullying during childhood but also to alleviate its negative consequences in adulthood should be considered to help people who have encountered adverse childhood experiences.