Background This study aimed to explore the mechanism by which school bullying among middle school students influences negative emotions and to test a moderated mediation model. Methods An anonymous cross-sectional survey employed a convenience sampling method among secondary school students in Anhui Province, eastern China, conducted from October to December 2023. Data were collected using a sociodemographic information questionnaire, the Core Self-Evaluation Scale (CSES), the Depression-Anxiety-Stress Scale-21 (DASS-21), and the Secondary School Students' Interpersonal Relationships Questionnaire. Statistical analysis was performed using AMOS 24.0 and SPSS 25.0. Results A total of 1,340 middle school students participated in this study. According to a simple mediation analysis based on Model 4, core self-evaluation partially mediated the relationships between school bullying and depression, anxiety, and stress, with indirect effect sizes of 0.32, 0.31, and 0.31, respectively, accounting for 37.67%, 34.07%, and 36.47% of the total effect. A moderated mediation analysis based on Model 14 further indicated that interpersonal relationships significantly moderated the relationship between core self-evaluation and depression, anxiety, and stress (interaction terms β = 0.11–0.22, p 0.001), with the strongest moderating effect observed for depression. After distinguishing the various dimensions of interpersonal relationships, it was found that peer, teacher-student, parent-child, and self relationships all significantly moderated the relationship between core self-evaluation and depression, anxiety, and stress (interaction terms β = 0.06–0.22, p 0.001), with the moderating effects of self and parent-child relationships being the most pronounced. Conclusion This study found that core self-evaluation partially mediated the relationship between school bullying and depression, anxiety, and stress; interpersonal relationships significantly moderated this mediating pathway. These findings provide empirical evidence for understanding the mechanisms through which school bullying affects the negative emotions of middle school students and for implementing targeted interventions.
Dai et al. (2026) studied this question.