Objective: To gain a better understanding of the emotional and behavioral problems associated determinants of primary and middle school students from Guangdong Province during the COVID-19 pandemic, so as to provide a basis for developing targeted intervention strategies. Methods: Using the method of convenience sampling, an online questionnaire survey was carried out among primary and middle school students from Guangzhou, Zhanjiang and Zhongshan from March to April 2020. The emotional and behavioral problems of primary and middle school students were assessed using the Conners Parental Symptoms Questionnaire(PSQ), and a self compiled questionnaire was used to collect basic information related to the primary and middle school students and the influencing factors of emotional and behavioral problems. A total of 7 755 valid questionnaires were retrieved and statistically analyzed using the chi square test and multivariate Logistic regression. Results: The detection rate of emotional and behavioral problems among children and adolescents aged 6 to 17-years-old in Guangdong Province was 14.8%; that was 21.0%, 14.4%, 7.3 %, and 10.1% in lower primary school students, upper primary school students, junior high school students, and high school students, respectively. The detection rate of the psychosomatic and hyperactivity index in boys was higher than that observed in girls, and the detection rate of anxiety in boys was lower than that observed in girls( P <0.05). There were statistically significant differences in emotional and behavioral problems in children in different grades( P <0.05). The results of the regression analysis showed that male students were at risk of psychosomatic ( OR= 1.37 , 95%CI =1.04-1.82) and hyperactivity disorders( OR=1.58, 95%CI =1.21-2.06), whereas the male gender was a protective factor for anxiety( OR=0.50, 95%CI =0.39-0.64). Grades were identified as the influencing factors of all of the factors related to emotional and behavioral problems. Students who reported excessive screen time and insufficient sleep were more likely to experience emotional and behavioral problems. Conclusion The detection rate of emotional and behavioral problems among primary and middle school students in Guangdong Province during the COVID-19 epidemic was high, which was associated with sex, grade, screen time and sleep. It is necessary to develop and implement targeted intervention measures.

: To investigate the current status of online classes, screen time and its influencing factors among primary school students in Guangdong during the 2019 novel coronavirus pandemic. Methods: Using the convenience sampling method, a total of 5 266 pupils aged 6-12-years-old from Guangzhou, Zhanjiang, and Zhongshan participated in the online questionnaire. ANOVA or chi square tests were performed to compare differences in online classes and screen time between grades, and multinomial Logistic regression was performed to analyze the correlates of recreational screen time. Results: The prevalence of prolonged recreational screen time was 42.2% and 55.2% on weekdays and weekends, respectively. Recreational screen time increased by 40.31 min/d on weekdays and 33.07 min/d on weekends, compared to usual school semesters. The average duration of an online class was (26.07±9.62) min, which totaled (110.41±51.98)min per day. Sex, grade, being the only child, and parents education levels were identified as the influencing factors of prolonged recreational screen time. Children who practiced moderate levels (weekdays: OR =1.27; weekends: OR =1.40; P <0.05) or lower levels of physical activity (weekdays: OR =1.86; weekend: OR =1.84; P < 0.05 ) were at a higher risk of prolonged recreational screen time than those who practiced more vigorous physical activity. Children whose parents limited their screen time to a moderate (weekdays: OR=1.61, P <0.05) or lower level (weekdays: OR=1.32, P < 0.05 ) had a higher risk of prolonged recreational screen time than those with a higher frequency. Children with parents recreational screen time ≥ 2 h/d had a higher risk of prolonged recreational screen time than the reference group; children who exhibited moderate to vigorous levels of physical activity <1 h/d (weekdays: OR=1.31, P <0.05), and those used electronic devices for learning 1-2 h/d (weekdays: OR =2.65; weekend: OR =2.65; P <0.05) or for ≥2 h/d (weekdays: OR =4.05, weekend: OR=5.24, P < 0.05 ) were at a higher risk of prolonged recreational screen time than the reference group. Conclusion During the COVID-19 pandemic, the level of screen time among children in Guangdong was high. Behavioral monitoring and targeted interventions are needed to promote children s health.