ABSTRACT
Objective: To study the current status of non-suicidal self-injury (NSSI) incidents among middle school students in Chengdu during the COVID-19 epidemic and to explore the mechanism of action of depression on the relationship between family environment and NSSI. Methods: Data were obtained from the Chengdu Positive Child Development (CDPD) cohort. In June and July 2020, after primary and secondary schools were reopened after the closure due to the COVID-19 epidemic, on-site questionnaire surveys were conducted with the Deliberate Self-Harm Inventory (DSHI), the Chinese Family Assessment Instrument (C-FAI), and Center for Epidemiologic Studies Depression Scale for Children (CES-DC), thereby obtaining the data of 3595 middle school students. Two-sample t-test and χ 2 test were used to compare the incidence of NSSI among middle school students of different grades and genders, and the Model 58 test of the SPSS PROCESS component was used to analyze the mediating effect of gender-mediated depression. Results: 1) The incidence of NSSI among middle school students in Chengdu during the COVID-19 epidemic was 49.67%. The incidence of NSSI among ninth-graders (80.70%) was significantly higher than those of the eighth graders (33.82%) and seventh graders (32.32%), and the incidence of NSSI among female middle school students (54.75%) was significantly higher than that of male students (44.52%). 2) Family environment ( r=0.34, P<0.001) and depression ( r=0.50, P<0.001) were positively correlated with NSSI. 3) Depression partially mediated the effect of family environment on NSSI, with the mediating effect accounting for 64.64% of the total effect. Compared with that of male students, the positive predictive effect between family environment and depression and that between depression and NSSI in female middle school students were more significant. Conclusion: During the COVID-19 pandemic, middle school students in Chengdu had a high incidence of NSSI, which indicates that the family environment should be improved, more attention should be given to gender differences, and early screening and intervention for depression should be strengthened to reduce the incidence of NSSI.