Objective: To explore cyberbullying and risk factors of middle school students, and to provide a reference for cyberbullying prevention in school settings. Methods: A stratified cluster random sampling method was used to select 12 940 students from three junior high schools and four senior high schools in Yixing City of Jiangsu Province, China, to conduct a questionnaire survey from March 1 to May 31, 2019. The Chi -square test was performed to compare differences in the prevalence of cyberbullying among groups with different sociodemographic characteristics, and the multivariate Logistic regression model was employed to analyze the risk factors. A risk predictive nomogram model was constructed and then verified. Results: Middle school students were found to be victims of cyberbullying at a rate of 12.3%. The Logistic regression results showed that alcohol use ( OR =1.93), lack of emotional management ( OR =1.30), feeling unsafe ( OR =1.70), not trusting people ( OR =1.66), increased daily online time ( OR =1.39), higher frequency of using social software or websites ( OR =2.24), poor relationships with family members ( OR =1.46), parental neglect ( OR =1.50), class leadership ( OR =1.30) and poor relationships with classmates ( OR =1.34) were risk factors for middle school students who were victims of cyberbullying ( P <0.05). Based on these 10 independent risk factors, the nomogram prediction model, had good discrimination ( AUC =0.73). Conclusion Cyberbullying is common among middle school students. Internet use, parental neglect and class leadership all have an impact on cyberbullying.

Objective:To explore the mediating effect of smoking, emotional control, and family relationship on the association between relational bullying victimization and perpetration.Method:A total of 11 462 participants were included in the study. Mediating effect model was used to analyze the mediating effect of smoking, emotional control, and family relationship between relational bullying victimization and perpetration.Results:Family relationship (mediation effect value: 0.119, 95% CI: 0.075-0.165, mediation ratio: 8.5%) and smoking (mediation effect value: 0.061, 95% CI: 0.031-0.105, mediation ratio: 4.4%) constitute a separate mediating effect. Family relationship, emotional control, and smoking constitute a chain mediation effect (mediation effect value: 0.007, 95% CI: 0.003-0.013, mediation ratio: 0.5%); family relationship and smoking constitute a chain mediation effect (mediation effect value: 0.036, 95% CI: 0.020-0.056, mediation ratio: 2.6%); emotional control and smoking constitute a chain mediating effect (mediation effect value: 0.007, 95% CI: 0.003-0.013, mediation ratio: 0.5%). Conclusion:Smoking, emotional control, and family relationship partially mediate relational bullying victimization and perpetration.