The sudden outbreak of COVID-19 has exerted a tremendous impact on the psyche of people around the world, especially adolescents. In order to provide a valuable theoretical basis for effective measures to prevent psychological problems in adolescents during public health emergencies in the future, this study examined the mediating effect of coping style (CS, including positive coping style (PCS) and negative coping style (NCS)) and the moderating effect of emotional management ability (EMA) on the relationship between the psychological stress response (PSR) and aggression (AGG) in adolescents during the COVID-19 epidemic in China. The Buss–Warren Aggression Questionnaire, Simplified Coping Style Questionnaire, and Emotion Management Questionnaire were employed to investigate the mental health of Chinese adolescents from April 10–20 (Time point 1, T1) and May 20–30 (Time point 2, T2), 2020. A total of 1,931 adolescents (aged 10–25 years, M = 19.18 years, 51.4% male) were examined at T1 and 334 adolescents (aged 11–25 years, M = 19.97 years, 48.7% male) were reinvestigated at T2. Overall, 17.6% of the participants at T1 and 16.8% at T2 reported obvious PSR activation. NCS partly mediated the relationship between the PSR and AGG, and the indirect effect was moderated by EMA reported at T2. There were regional differences in the moderated mediation model in low-risk areas at T1. The moderated effects of EMA at T1 and T2 were opposite. Specifically, high EMA resulted in a stronger relationship between NCS and AGG at T1, whereas high EMA resulted in a weaker relationship between NCS and AGG at T2. Psychological reactions resulting from sudden public health events may trigger AGG in younger individuals. However, EMA may have a buffering effect on the onset of AGG. This research expands our understanding of the development of AGG in adolescents during the pandemic.

Background The sudden outbreak of COVID-19 had a great impact on the physical and mental health of people all over the world, especially for students whose physical and mental development was not yet mature. In order to understand the physical and mental conditions of students during the epidemic period and provide a theoretical basis for coping with psychological problems in public health emergencies, this study explored the mediating role of sleep disorders in the effect of the psychological stress response (PSR) on non-suicidal self-injury (NSSI), along with the moderating role of emotional management ability (EMA). Methods The SRQ-20, Pittsburgh Sleep Quality Index, NSSI Behavior Questionnaire, and Emotional Management Questionnaire were used to investigate the mental health of Chinese students in April 10–20 (Time point 1, T1) and May 20–30 (Time point 2, T2), 2020. A total of 1,955 students (Mage = 19.64 years, 51.4% male) were examined at T1 and 342 students (Mage = 20.06 years, 48.2% male) were reassessed at T2. Results Overall, the detection rate of PSR and NSSI were 17.60% (n = 344) and 24.90% (n = 486) respectively in the T1 sample, and were 16.37% (n = 56) and 25.44% (n = 87), in the T2 sample. We also found that sleep disorders played a mediating role in the effect of PSR on NSSI in the T1 and T2 samples. In addition, EMA was shown to regulate the effect of PSR on sleep disorders and the effect of sleep disorders on NSSI in the T1 samples. Conclusion We found that PSR resulting from public health emergency might lead to NSSI behaviors in individuals. PSR may also cause sleep disorders, which can bring about NSSI. However, these effects were also moderated by the EMA. This research expands our understanding of PSR and NSSI in students during the pandemic.