Abstract Chinese children and adolescents are experiencing dramatic changes in their lifestyle and the environment. Given the growing burden of myopia, obesity, and mental health problems among school age children, school health services are presented with new challenges. It is essential to promote and implement the underlying principle of "health first" for society as a whole, while aiming to improve the collective health literacy of schools, optimizing school health management systems, and adopting a comprehensive healthy school program in order to support every school to become a foundation for healthy living.

Abstract Myopia is a complex disease influenced by multiple factors, and its prevention and control require a thorough identification and monitoring of its risk factors. The paper examines the defocus characteristics of the visual environment and their association with myopia among children and adolescents, and further describes their role in the prevention and control of myopia, as well as analyses the limitations of the current study and proposes directions for further research. Finally, the paper calls attention to the etiological significance of the defocus characteristics in the visual environment during the development of myopia among children and adolescents, which could provide a scientific basis for optimizing the learning environment and designing other measures to promote myopia prevention and control among children and adolescents.

Abstract The physical and mental health issues of children and adolescents in China are becoming increasingly prominent. Integrating physical education deeply into the educational system and maximizing its role in fostering personal development, preventing common illnesses among students, and promoting mental health has emerged as the intersection of school health and sports. The article systematically arranges the development history and patterns of physical education in Chinese schools, summarizes the existing difficulties in the integration of physical education and educational system, and presents improvement suggestions to provide a basis for enhancing the integration system and promote the comprehensive development of children and adolescents.

Objective: To study the correlation between short sleep duration and screening myopia among primary and middle school students in Beijing, so as to provide a scientific basis for the comprehensive prevention and control of myopia among students. Methods: Using a stratified cluster random sampling, 25 593 primary and middle school students from 16 districts of Beijing were selected from September to November 2023. The National Common Diseases and Health Influencing Factors Monitoring Survey Questionnaire was used to conduct a questionnaire survey, and visual acuity was tested according to the Specification for the Screening of Refractive Error in Primary and Middle School Students. The reporting rates of short sleep duration and detection rates of screening myopia among primary and middle school students were compared using the Chi square test. Binary Logistic regression was used to analyze the correlation between short sleep duration and screening myopia. Results: About 68.63% of students reported short sleep duration. There was a statistically significant difference in the reporting rate of short sleep duration among students in different school stages ( χ 2=981.18, P <0.01), with the lowest reporting rate of vocational high school students (47.07%) and the highest reporting rate of ordinary high school students (76.17%). The detection rates of screening myopia among primary school students ( 57.09% ) and middle school students (76.53%) who reported short sleep duration were higher than those who reported enough sleep duration (52.65%, 71.94%), with satistically significant differences ( χ 2=14.83, 17.96, P <0.01). The results of binary Logistic regression analysis showed that primary and middle school students with short sleep duration had a higher risk of developing screening myopia, compared to students with enough sleep duration ( OR =1.25); after adjusting for confounding factors such as educational stage, gender, region, boarding situation, primary and secondary school students with short sleep duration still had a higher risk of screening myopia ( OR =1.26) ( P <0.01). The analysis results stratified by educational stage showed that primary school students from grades 4-6 and middle school students with short sleep duration had a higher risk of screening myopia ( OR=1.18, 1.20, P <0.01). Conclusions Primary and secondary school students in Beijing with short sleep duration sleep have a higher risk of developing screening myopia. Families, schools, and society should ensure enough sleep duration to reduce the occurrence of myopia among students.

Objective: To analyze the status of outdoor activities on weekends among children and adolescents of different educational stages in Shanghai and their impact on myopia, so as to provide a basis for formulating more specific prevention and control protocol of myopia. Methods: From September to October 2022, a stratified cluster random sampling method was employed to select 84 schools (27 kindergartens, 21 primary schools, 15 junior high schools and 21 high schools) across Shanghai, enrolling a total of 28 654 children and adolescents aged 4 to 18 for the study. Ophthalmic examinations were conducted to ascertain the prevalence of myopia among children and adolescents. Additionally, a questionnaire survey was administered to collect data on outdoor activity duration and associated factors. Multivariate Logistic regression analysis was utilized to investigate the associated factors of outdoor activity levels on weekends. Results: The overall myopia detection rate among children and adolescents was 58.4%, with a higher rate observed in girls (59.2%) compared to boys (57.6%). The myopia detection rates for children and adolescents with an average daily outdoor activity duration of ≥2 h and <2 h on weekends were 54.6% and 68.8%, and the differences were statistically significant ( χ 2=8.12,460.89, P <0.01). Multivariable Logistic regression analysis revealed that girls ( OR =0.80), those with a myopic parent ( OR =0.68), schools from urban districts ( OR =0.72), higher education stages (primary school: OR =0.65, junior high school: OR =0.24, high school: OR =0.14) and spending≥2 h/d on homework during weekends ( OR =0.57) among children and adolescents were less likely to engage in outdoor activities for ≥2 h on weekends ( P <0.01). After incorporating gender, parental myopia status, educational stage, school location, average daily duration on weekends for spending on homework, electronic product usage and outdoor activities as dependent variables in a multivariate Logistic regression analysis, the results showed that children and adolescents with an average outdoor activity duration for ≥2 h on weekends had a lower risk of myopia ( OR =0.86, P < 0.01). Conclusions The level of outdoor activity among children and adolescents on weekends needs to be improved. Outdoor activities on weekends is an associated factor for myopia among children and adolescents. Particularly, girls, those with myopic parents, schools from urban districts, and spending long hours on homework during weekends among children and adolescents require increased attention.

Objective: To investigate the visual acuity and correction conditions of children and adolescents in Shanghai, so as to provide a scientific basis for developing intervention measures to prevent myopia and protect vision among children and adolescents. Methods: From October to December 2022, a stratified cluster random sampling survey was conducted, involving 47 034 students from 16 municipal districts in Shanghai, covering kindergartens (≥5 years), primary schools, middle schools, general high schools and vocational high schools. According to the Guidelines for Screening Refractive Errors in Primary and Secondary School Students, the Standard Logarithmic Visual acuity Chart was used to examine naked vision and corrected vision of students, and general information was collected. The distribution and severity of visual impairment in different age groups were analyzed, and χ 2 tests and multivariate Logistic regression were used to explore factors associated with visual impairment. Results: The detection rate of visual impairment among children and adolescents was 76.2%, with a higher rate among females (78.8%) than males ( 73.8 %), higher among Han ethic students ( 76.2 %) than minority students (71.2%), and higher among urban students (76.7%) than suburban students (75.8%), all with statistically significant differences ( χ 2=162.6, 10.4, 5.5, P <0.05). The rate of visual impairment initially decreased and then increased with age, reaching its lowest at age 7 (53.8%) and peaking at age 17 (89.6%) ( χ 2 trend = 3 467.0 , P <0.05). Severe visual impairment accounted for the majority, at 56.6%, and there was a positive correlation between the severity of visual impairment and age among children and adolescents ( r =0.45, P <0.05). Multivariate Logistic regression showed that age, BMI, gender, ethnicity and urban suburban status were associated with visual impairment ( OR =1.18, 1.01, 1.38 , 0.79, 0.88, P <0.05). Among those with moderate to severe visual impairment, the rate of spectacle lens usage was 62.8%, yet only 44.8 % of those who used spectacle lens had fully corrected visual acuity. Females (64.9%) had higher spectacle lens usage rates than males (60.6%), and general high school students had the highest spectacle lens usage (83.9%), and there were statistically significant differences in gender and academic stages ( χ 2=57.7, 4 592.8, P <0.05). Conclusions The rate of spectacle lens usage among students with moderate to severe visual impairment is relatively low, and even after using spectacle lens, some students still do not achieve adequate corrected visual acuity. Efforts should focus on enhancing public awareness of eye health and refractive correction and improving the accessibility of related health services.

Objective: To analyze the space time characteristics of poor vision among primary and secondary school students in Chengdu, in order to provide the reference for formulating myopia prevention and control policies for students. Methods: The data relating to poor vision among primary and secondary school students in Chengdu from 2021 to 2023 were sourced from the Sichuan Students Physical Health Big Data Center. The districts and counties of Chengdu were divided into three circles, including the main urban area, suburban districts and counties, and suburban districts and counties. The Chi square test was used for inter group comparison, and the Cochran-Armitage test was used to analyze the trend of changes. Global and local Moran s I were used to analyze spatial clustering. Results: The detection rates of poor vision among primary and secondary school students in Chengdu from 2021 to 2023 were 62.47%, 61.61% and 60.78%, respectively, showing a decreasing trend ( Z=-32.01, P <0.01). For each year, the higher detection rate of poor vision among students was detected in the higher level of education, and differences were statistically significant ( χ 2=161 549.47, 173 471.87, 233 459.09, P <0.01). The rate of poor vision among primary and secondary school students gradually decreased from the central districts and counties of Chengdu to the surrounding districts and counties for each year, and the differences were statistically significant ( χ 2=299.20, 776.22, 633.16, P <0.01). The spatial autocorrelation analysis showed that the first circle of Chengdu City was mainly characterized by high-high agglomeration ( P <0.01), with the rate of poor vision among primary school students in Wuhou District in 2023 exhibiting a low-high anomaly. The third circle was mainly characterized by low-low aggregation ( P <0.01), while the spatial clusterings of the second circle was not significant ( P >0.05). Conclusions The myopia prevention and control work in Chengdu has achieved preliminary results. It should continue to consolidate existing achievements and implement targeted myopia prevention and control measures based on regional characteristics.

Objective: To understand the prevalence of myopia among primary and secondary school students in minority areas of Yunnan Province, and to explore the influence of outdoor activities and short-distance use of eyes, so as to provide a basis for early myopia intervention. Methods: In October 2020, the survey was conducted among 1 782 primary and secondary school students in three cities of Yunnan through a multi stage random cluster sampling method. All subjects underwent a questionnaire survey and the visual acuity examination at baseline. The first follow-up was conducted in October 2021 to obtain 1 691 valid samples, and the second follow-up was conducted in May 2023 to obtain 1 367 valid samples. Factors associated with myopia among primary and secondary school students were explored by using generalized estimating equations. Results: The prevalence rates of myopia in 2020, 2021 and 2023 were 52.64%, 61.62% and 69.35%, respectively, showing an increasing trend ( χ 2 trend =91.77, P <0.05). The results of multivariate regression analysis on the generalized estimation equations showed that age at baseline ( OR =1.31), girls ( OR =1.76), Hani ethnicity ( OR =0.75), Bai ethnicity ( OR =0.69), parental myopia ( OR =1.97-2.29), parents often reducing children s exercise time for homework or tutoring ( OR =1.35), less than 1 time or 2-3 times of ball sports per week ( OR =1.27, 1.20 ), reading and writing in the classroom during the break ( OR =1.27), reading in direct sunlight occasionally ( OR =1.20), using only desk lamp for writing at home ( OR =0.71), more than 1 hours of short-distance eye use for a break once ( OR =1.23) were associated with myopia among primary and secondary school students ( P <0.05). Conclusions Outdoor activities and short-distance use of eye among primary and middle school students in minority areas in Yunnan province are suboptimal. Enhancing the related environmental and behavioral factors can effectively mitigate the occurrence and progression of myopia.

Objective: To evaluate the intervention effectiveness of co-occurrence and prevention for myopia and obesity among primary and secondary school students, so as to provide a scientific basis for the development of comprehensive intervention measures in myopia and obesity. Methods: From September 2022 to September 2023, a cluster random sampling method was used to select 6 primary schools and 6 junior high schools from Tongzhou District, Beijing. Participants were randomly assigned to an intervention group (914 before intervention and 754 after intervention) and a control group (868 before intervention and 652 after intervention), with an expected duration of one academic year. Based on the RE-AIM framework, integrate resources from families, schools, communities, and medical institutions to develop a school-based intervention technology packagefor the co-occurrence and prevention of myopia and obesity in children. The intervention group received intervention according to the comprehensive intervention technology package, while the control group did not receive any intervention measures. Relevant health indicators during the baseline period and after intervention were measured and collected, and groups were compared by Chi quest test, t-test and Wilcoxon rank sum test. Results: After intervention, the uncorrected visual acuity of primary and secondary school students in the intervention group (4.79±0.30) and the control group (4.77±0.33) both decreased compared to those before intervention (4.80±0.30, 4.90±0.32) ( t =-7.00,-5.24); the decrease in uncorrected visual acuity in the intervention group was smaller than that in the control group( t =5.33)( P <0.01). After intervention, body mass index, waist circumference, hip circumference, and body fat percentage of primary and secondary school students in the intervention group decreased compared to those before intervention. However, the changes in these indicators were not statistically significant ( t/Z =-0.03, - 0.36，- 0.30，- 0.01, P >0.05); the above indicators in the control group increased compared to those before intervention, but only hip circumference and body fat percentage showed statistically significant changes ( t/Z =2.17, 2.62, P <0.05). After intervention, both the intervention group and the control group showed increases in systolic and diastolic blood pressure compared to those before intervention(intervention group: t =2.16,5.29; control group: t =6.84,5.07); the intervention group had lower systolic and diastolic blood pressure than the control group( t = -5.27 , -2.08)( P <0.05). After intervention, the intervention and the control groups had statistically significant differences in cognitive accuracy(92.48%, 69.33%) in terms of "outdoor exercise can prevent myopia" and "having 5 servings of adult fist sized vegetables and fruits every day" ( χ 2=6.30, 7.86, P <0.05). There was a statistically significant difference in the proportion of primary and secondary school students in the intervention group (40.98%) and the control group (35.43%) for "who did not drink sugary drinks for every day in the past 7 days" ( χ 2=4.32, P <0.05). After intervention, the intervention group and the control group showed increases in "school outdoor activity duration on school days" and "outdoor activity duration on rest days" compared to those before intervention ( t/Z =-13.32,-9.71;- 2.59，-2.69）；the behavior rate of "visual acuity measurement frequency at least once every 3 months" in the intervention group (46.68%) and the control group (52.76%) increased compared to those before intervention (36.43%, 44.01%), and the increases in the intervention group were greater than that in the control group ( χ 2=17.52,11.08) ( P <0.05). Conclusions Comprehensive intervention measures have significant intervention effects on controlling the occurrence and development of comorbidity of myopia and obesity in children. It could actively promote collaboration and cooperation among families, schools, communities and medical institutions to reduce the occurrence of myopia and obesity among primary and secondary school students.

Objective: To explore the relative importance of different food attributes and levels in food decision making of school aged children, and to understand their meal preferences, so as to provide the evidence for formulating precise intervention strategies for dietary behaviours of school aged children. Methods: From May to June 2024, a total of 854 children aged 11 to 15 years old were selected from 2 middle schools (each school in urban and rural areas) in both Hubei Province and Anhui Province by stratified cluster random sampling method to conduct a D-optimal discrete choice experiment. The mixed Logit model was used to analyze children s preference for meal attributes and different levels, and to calculate the relative importance (RI) of attributes and willingness to pay (WTP) in meal choices. Results: The included five food attributes had statistical significance on meal choice of school aged children ( P <0.05). The relative importance of food attributes affecting the meal choices of school aged children in descending order were dining mode ( RI =31.26%), food varieties ( RI =30.56%), cooking method( RI =23.84%), taste( RI =8.06%) and price ( RI =6.27%). Among them, school aged children preferred home cooked meals ( β =0.74) (WTP=86.3 yuan),varied foods(grain/tubers+vegetables+fish, meat, eggs and beans) ( β =0.61) (WTP=71.9 yuan), fried/roasted cooking ( β =0.51) and spicy taste ( β =0.33).Price was negatively correlated with meal choices( β =-0.01) ( P <0.05). Based on residential area and body mass index (BMI), the stratified analysis showed that dining mode was highest in the relative importance for rural children with overweight and obese children ( RI =31.28%,34.17%), both of whom preferred home cooked meals ( β =0.76, 0.91), and meals containing fish, meat, eggs and beans with grain/tubers or grain/tubers and vegetables in terms of food choice (area: β =0.53, 0.53 ; BMI: β =0.55, 0.56) ( P <0.05). Conclusions School aged children have different preferences for different attributes of meals. The quality of school meals should be improved,the cost of buying healthy meals should be reduced,targeted family health education should be carried out,and healthy cooking methods should be advocated.