Objective: To explore the association of screen time with self-injury behavior in primary school students in China, to provide evidence for prevention on self-injury behavior. Methods: From June to November in 2017, 1 090 primary school students were selected by stratified cluster sampling method from Zhejiang, Guangdong, Jiangxi, Sichuan and Guizhou province in China, to analyze the association between screen time and incidence of self-injury. Results: Totally 5.6% students reported screen time over 2 hours per day, boy, rural students, students with low health literacy, ever drinking had a higher rate of screen overuse(χ 2=12.35, 6.94, 6.86, 16.86, P<0.05). The prevalence of screen overuse varied significantly by amount of pocket money(P<0.01). The prevalence of self-injury was 11.3%, students from western areas, boy, grade three, from rural area, adult relatives as guardians, low health literacy, smoking, drinking and screen time over 2 hours per day had a higher rate of self-injury behavior(χ 2=27.31, 11.49, 23.91, 22.12, 15.11, 55.16，19.03, 25.16, 19.35, P<0.05). Compared with the students with screen time less than 2 hours per day, multiple Logistic regression analyses showed that, the OR(95%CI) values of self-injury was 2.62(1.31-5.23) among students with screen time less than 2 hours per day. Conclusion The risk of self-injury behavior is related to screen time in primary school students, specific health education should be conducted to reduce screen time.

Objective: To investigate the association of health literacy and incidence of self-injury, intentional injury in primary and middle school students in China, to provide guidance for prevention on self-injury and intentional injury in adolescence. Methods: From June to November in 2017, a total of 2 173 primary and middle school students were selected by stratified cluster sampling method from Zhejiang, Guangdong, Jiangxi, Sichuan and Guizhou province in China, The association between health literacy with incidence of self-injury, intentional injury was analyzed. Results: The score of health literacy among 2 173 students was(13.13±2.27), with primary school students (12.79±2.55) lower than middle school students (13.49±1.88) (t=-7.29，P<0.05), the prevalence of self-injuries was 11.1%, primary school students was 11.3% which was similar with that of middle school students was 11.0% (χ2=0.06，P>0.05), the prevalence of intentional injury was 17.8%, the primary school students was 22.4% which was significantly higher than that of middle school students (13.2%) (χ2=31.31，P<0.05). Compared with the students with high health literacy, multiple Logistic regression analyses showed that, the OR(95%CI) values of self-injury, intentional injury were 2.38(1.78-3.20) and 1.45(1.11-1.88). Conclusion The risk of self-injuries and intentional injury of primary and middle school students was related to health literacy, the health education should be conducted to improve their health literacy.