The prevalence of obesity among children and adolescents has been rapidly rising in Mainland China in recent decades, both in urban and rural areas. There is an urgent need to develop effective interventions to prevent childhood obesity. Limited rigid data regarding children and adolescent overweight prevention in China are available. A national random controlled school-based obesity intervention program was developed in the mainland of China. The study was designed as a national multi-centered cluster randomized controlled trial involving more than 70,000 children and adolescents aged 7–18 years from 7 provinces in China. In each center, about 12–16 primary and secondary schools, with totally at least 10000 participants were randomly selected (Primary: Secondary = 1:1). All of the selected schools were randomly allocated to either intervention or control group (Intervention: Control = 1:1).The multi-components school-based and family-involved scheme was conducted within the intervention group for 9 month, while students in the control group followed their usual health practice. The intervention consisted of four components: a) Create supportive school and family environment, b) Health lifestyles education and related compulsory physical activities, c) Instruct and promote school physical education, d) Self-monitor obesity related behaviors. Four types of outcomes including anthropometric, behavioral, blood chemical and physical fitness were measured to assess the effectiveness of the intervention program. This is the first and largest multi-centered school-based obesity intervention program with the consideration of geographical and social-demographic characteristics of the rapidly increased obesity prevalence of Chinese children and adolescent. The intervention is based on Social Cognitive Theory and Social-Ecological Model of Health, and follows a stepwise approach guided by PRECEDE-PROCEED (P-P) Model and Intervention Map. The results of and lesson learned from this study will help guide future school-based national childhood obesity prevention programs in Mainland China. January 22, 2015; Registration number: NCT02343588

To understand the prevalence of myopia in primary and middle school students in 6 provinces and the possible influencing factors. Primary and middle school students were selected through multistage cluster sampling in 60 primary and middle schools in 6 provinces in China. The questionnaire survey and eyesight test were conducted among all the students selected according to the national student's physique and health survey protocol. Pearson chi-square test and binary multivariate logistic regression analysis were done to identify the influencing factors for myopia in students. The prevalence of myopia among primary and middle school students surveyed was 55.7%, the gender specific difference was statistically significant (59.7% for girls, 51.9% for boys) (P<0.01). The prevalence of myopia increased with age obviously. The prevalence was 35.8% in age group 6-8 years, 58.9% in age group 10-12 years, 73.4% in age group 13-15 years and 81.2% in age group 16-18 years, the differences were statistically significant (P<0.001). Single factor and multivariate analysis showed that parents' myopia, distance between computer screen and eyes, distance less than 30 cm between eyes and book while reading, distance less than 10 cm between chest and the table edge while studying, distance less than 3 cm between fingers and pen tip, sleep time, average outdoor activity time during last week, school sport activities in the afternoon, the size of television set at home, time spent on watching TV and playing computer were the influencing factors for myopia. The prevalence of myopia is till high in primary and middle school students. Myopia is associated with both genetic factors and individual eye health related behaviors.

We set up a series of school-based interventions on the basis of an ecological model targeting sugar-sweetened beverage (SSB) reduction in Chinese elementary and middle schools and evaluated the effects. A total of 1046 students from Chinese elementary and middle schools were randomly recruited in an intervention group, as were 1156 counterparts in a control group. The interventions were conducted in the intervention schools for one year. The participants were orally instructed to answer all the questionnaires by themselves at baseline and after intervention. The difference in difference statistical approach was used to identify the effects exclusively attributable to the interventions. There were differences in grade composition and no difference in sex distribution between the intervention and control groups. After adjusting for age, sex, and group differences at baseline, a significant reduction in SSB intake was found in the intervention group post intervention, with a decrease of 35.0 mL/day (p = 0.034). Additionally, the frequency of SSB consumption decreased by 0.2 times/day (p = 0.071). The students in the elementary schools with interventions significantly reduced their SSB intake by 61.6 mL/day (p = 0.002) and their frequency of SSB consumption by 0.3 times/day (p = 0.017) after the intervention. The boys in the intervention group had an intervention effect of a 50.2 mL/day reduction in their SSB intake (p = 0.036). School-based interventions were effective in reducing SSB consumption, especially among younger ones. The boys were more responsive to the interventions than the girls. (ChiCTR, ChiCTR1900020781.)

Adolescence is a susceptible period to establish health-risk behaviors, which may have an impact on academic performance. The aim of this study was to investigate the association between health-risk behaviors (HRBs) and perceived academic performance (PAP) of adolescents in Shanghai, China. The data of the present study included three-round Shanghai Youth Health-risk Behavior Survey (SYHBS). This cross-sectional survey investigated multiple HRBs of students involved in dietary behaviors, physical activity and sedentary behaviors, intentional and unintentional injury behaviors, and substance abuse behaviors, as well as PAP by using self-reported questionnaire. Using a multistage random sampling method, 40,593 middle and high school students aged 12 to 18 years were involved. Only participants with complete data on HRBs information, academic performance and covariates were included. A total of 35,740 participants were involved in analysis. We used ordinal logistic regression to analyze the association between each HRB and PAP adjusting for sociodemographic, family environment and duration of extracurricular study. The results showed that students who did not eat breakfast or drink milk everyday were more likely to have a lower PAP, with a decreased odds of 0.89 (95%CI: 0.86–0.93, P<0.001) and 0.82 (95%CI: 0.79–0.85, P<0.001), respectively. The similar association was also found in students who did exercise ≥60 minutes for less than 5 days/week, spend time on watch TV beyond 3 hours/day and other sedentary behaviors. Most intentional and unintentional injuries, and ever smoked were associated with a lower PAP. Our finding suggests that multiple HRBs negatively associated with PAP of adolescents. It needs to raise public health concerns with HRBs in adolescents, and to develop and implement comprehensive interventions on HRBs.