Objective: To develop a 24 hour physical activity index for school aged children, and to analyze the association of 24 hour physical activity index with screening myopia and obesity, so as to provide a more effective assessment tool for student health risk screening. Methods: From April to June 2024, a total of 451 students in Grades 3-4 from two monitored primary schools in Shanghai were selected using stratified cluster random sampling method. Data on eight core indicators, including daily moderate to vigorous physical activity time, total physical activity time, outdoor activity time, screen time, sleep duration, sleep efficiency, social jetlag and daytime sleepiness, were collected through questionnaires and accelerometer monitoring. Each indicator was standardized and synthesized into a 0-80 point school aged children s 24 hour physical activity index. Spearman correlation analysis and t-test were used to assess consistency between questionnaire and accelerometer derived indices. Multivariate Logistic regression was applied to analyze the association of strength of the composite index with single behavior indicators in screening myopia and overweight/obesity. Results: The compliance rates were higher for moderate to vigorous physical activity time and screen time (50.8%, 98.7%), while the compliance rate for outdoor activity time was only 42.6%, and that for sufficient sleep duration was merely 10.2%. There was no significant difference between the total scores derived from the questionnaire and accelerometer methods (45.13±5.83, 45.05±6.87, t=0.29, P >0.05), but they showed a strong positive correlation ( r=0.58, P <0.01). Multivariate Logistic regression revealed that adjusting for individual behaviors such as grade, gender and both parents being myopic, among single behavior indicators of 24 hour physical activity index, only insufficient outdoor activity time was significantly associated with screening myopia among school aged children ( OR=1.50, 95%CI =1.01-2.21); the detection risk of screening myopia and obesity in the low index group were higher than those in the high index group ( OR=2.47, 95%CI =1.02-5.96; OR=16.63,95%CI = 5.99- 46.20) (all P <0.05). Conclusion The developed 24 hour physical activity index for school aged children demonstrates good measurement accuracy and shows stronger associations with screening myopia and obesity than single behavior indicator.

Objective: To analyze the independent and interaction effects of daytime outdoor light exposure and moderate to vigorous physical activity (MVPA) duration on sleep quality of primary school students, so as to provide scientific evidence for interventions on children s sleep health. Methods: From April to June 2024, a total of 444 students from grades 3 and 4 in 2 primary schools in Jiading District, Shanghai were selected using stratified random cluster sampling method for continuous 7 day monitoring. Wearable devices "Clouclip" were used to monitor daytime outdoor activity time (represented by time with light intensity ≥ 1 000 lx ), and accelerometers were used to monitor MVPA time and sleep quality related indicators. Multiple linear regression was used to analyze the associations of daytime outdoor activity and MVPA with sleep quality. Results: Both daytime outdoor light exposure and MVPA duration(longer actual sleep duration per night,longer time in bed,fewer awakening and shorter post sleep awakening shic) were independently associated with multiple sleep indicators( β =0.52, 0.46, -0.83, -2.19, all P <0.05), with no significant interaction between the associations ( P >0.05). After controlling for MVPA, more daytime outdoor light exposure was significantly and independently associated with longer actual sleep time ( β =0.50, 95% CI =0.21-0.79, P <0.05). After controlling for light exposure, longer MVPA duration was independently associated with shorter post-sleep awakening duration ( β=-4.15, 95% CI = -6.33 to -1.96, P <0.05). Conclusion Increased daytime outdoor activity and MVPA are both associated with better sleep quality in primary school students.

Objective To assess the dietary quality of preschool children and explore the relationship between feeding practices and dietary quality.Methods Relying on the Shanghai Maternal-Child Pairs Cohort,3 177 preschool children were selected as the subjects for this study,and questionnaire were surveyed on their dietary intake and feeding practice.The diet balance index was used to evaluate dietary quality among preschool children.High bound score(HBS),the low bound score(LBS),and the dietary quality distance(DQD)were calculated to respectively reflect overall dietary overconsumption,insufficiency,and imbalance.Logistic regression was utilized to analyze the association between feeding practice and dietary quality in preschool children.Results The HBS,LBS,and DQD of the subjects were 2(0,8),22.19±10.80,and 26.78±9.57,respectively.Only 7.68%of the children had a balanced dietary intake,with 74.73%and 33.99%of overall dietary intake being inadequate and excessive,respectively.Parental perceived weight were negatively associated with the risk of moderate to high over intake among children(aOR=0.79,95%CI:0.63-0.98).The higher the perceived responsibility(aOR=1.19,95%CI:1.03-1.37)score,the lower the monitoring score(aOR=0.83,95%CI:0.74-0.93),and the higher the likelihood that the child had a moderate to high under intake.The scores of pressure to eat were also positively correlated with the risks of under intake and moderate to high overall unbalance in preschool children(aOR=1.15-1.39,95%CI:1.02-1.63).Conclusion Preschool children commonly experience dietary imbalance,with inadequate and excessive intake coexisting.Parental perceived weight and monitoring were positively associated with preschoolers'dietary quality,whereas perceived responsibility and pressure to eat were negatively associated with it.

Objective To explore the association between psychological resilience and internet addiction among senior primary school students,so as to provide a scientific basis for formulating strategies for preventing internet addiction and enhancing psychological resilience in this group.Methods A stratified cluster sampling method was employed.In May 2021,a total of 1 618 fourth-and fifth-grade students from 5 primary schools in Jiading District,Shanghai were surveyed on psychological resilience and internet addiction through questionnaires.Independent sample t-tests,chi-square tests,and Logistic regression models were used for data analysis.Results Among the 1 618 students,the prevalence rate of internet addiction was 8.8%(142 students).The total score of psychological resilience(t=6.215,P<0.001)and the scores of three dimensions,namely family support(t=3.509,P<0.001),goal focus(t=6.965,P<0.001),and positive perception(t=5.887,P<0.001),of those reported with internet addiction were all significantly lower than those without internet addiction.Multivariate logistic regression analysis showed that compared with individuals with low psychological resilience,those with moderate(aOR=0.395,95%CI:0.267-0.584,P<0.001)and high psychological resilience(aOR=0.167,95%CI:0.077-0.365,P<0.001)had a lower probability of internet addiction.The three sub-dimensions of psychological resilience,namely goal focus,positive perception and family support,also showed a statistically significant negative association with internet addiction in these students.Conclusion Nearly one-tenth senior primary school students in Jiading District self-reported internet addiction.Higher levels of psychological resilience were associated with a lower probability of internet addiction among senior primary school students.Focusing on enhancing the goal focus,positive perception and family support dimensions in psychological resilience may be of great significance for preventing internet addiction among senior primary school students.

Objective: To explore the role of outdoor activity in the relationship between infancy responsive caregiving trajectories and early childhood development, so as to provide a theoretical basis for the promotion of early child development. Methods: The study participants were drawn from the Shanghai Maternal-Child Pairs Cohort and 4 723 mother-child pairs who completed responsive caregiving questionnaires at 2, 6 and 12 months old were included. Questionnaires were used to assess children s responsive caregiving and average daily hours of outdoor activity at 2 years of age. The Age-Stage Questionnaire, Third Edition (ASQ-3) was used to evaluate children s development problems at 2-5 years old. Group based trajectory model was applied to fit infancy responsive caregiving trajectory. Modified Poisson regression was used to analyze associations between different responsive caregiving trajectory groups and child development, and moderating effects were tested for hours of outdoor activity. Results: Infancy responsive caregiving trajectories were categorized into general group ( n =3 871), declining group( n =160), and fluctuating group( n =646). After adjusting for confounding factors, such as parents educational level, annual household income, maternal progestation body mass index,maternal tobacco exposure during pregnancy,maternal anxiety and depression during pregnancy, maternal age at delivery,maternal gestational age,maternal mode of delivery, children s gender,children s birth weight, and duration of breastfeeding, the results of modified Poission regression analysis showed that compared with the general group, children at the age of 2 in declining and fluctuating group had increased risks of suspected developmental delays in communication, gross motor, fine motor, problem solving, and personal-social scales ( OR =1.41,1.31,1.35,1.23,1.21；1.07,1.08,1.08,1.09,1.06);but children only had increased risk of suspected developmental delays in communication of declining group ( OR =1.08), personal-social scales of fluctuating group ( OR =1.06) at 3-5 years of age ( P <0.05). At lower levels of outdoor activity, children in fluctuating group had reduced scores in communication ( β =-1.41), fine motor ( β =-2.34), problem solving ( β =-1.11) and personal-social scales ( β =-1.99) as compared to general group; and children in declining group had reduced scores in gross motor ( β =-4.78)( P <0.05). While at higher levels of outdoor activity, no differences were found between children in fluctuating, declining groups and those in general group in scores of different scales ( P >0.05). Conclusion Prolonged outdoor activity attenuates the adverse effects of declining and fluctuating trajectories of infancy responsive caregiving on early childhood development.

Objective: To understand 24 h physical activity levels of children aged 8-9 years in Pudong New Area and to explore its association with metabolic syndrome, so as to provide scientific basis for children s participation in physical activities and reducing the risk of metabolic syndrome. Methods: A stratified cluster random sampling method was adopted to select 13 schools in Pudong New Area, Shanghai. A total of 2 013 primary school students aged 8-9 years old were included as the research subjects. During September 2021 to December 2022, Actigraph GT3X accelerometer, height measuring gauge, electronic sphygmomanometer and waist circumference tape was used to measure physical activity, height, blood pressure and waist circumference, respectively. A total of 5 mL of venous blood was collected from students, and the levels of triglycerides (TG), highdensity lipoprotein cholesterol (HDL-C) and fasting plasma glucose (FPG) were detected, and online questionnaires were conducted. The ttest and oneway ANOVA were employed to compare the differences in 24 h physical activity levels among children with different characteristics. Multivariate Logistic regression was used to analyze the association between the 24 h physical activity levels and metabolic syndrome as well as its components. Results: Among primary school students, the average daily time of moderate to vigorous physical activity (MVPA) was (34.25±13.49)min, the attainment rate was 1.59%. The average daily sleep (SLP) time was (538.27±28.53) min, attainment rate was 1.89%. The detection rates of metabolic syndrome, abdominal obesity (AO), elevated blood pressure (BP), elevated TG, low HDL-C, and elevated FPG were 2.48%, 34.53%, 10.38%, 10.73%, 1.24% and 0.70%, respectively. Multivariate Logistic regression analysis showed that, for every 10minute increase in sedentary behavior (SB) time, the risks of AO, elevated BP, and elevated TG increased by 2% ( OR=1.02, 95%CI =1.01-1.04), 5% ( OR=1.05, 95%CI =1.01-1.08), and 6% ( OR= 1.06, 95%CI =1.02-1.11), respectively ( P <0.05). For every 10minute increase in MVPA time, the risk of metabolic syndrome decreased by 27% ( OR=0.73, 95%CI=0.57-0.93, P <0.05). For every 10 minute increase in SLP time, the risks of AO, elevated BP, and metabolic syndrome decreased by 16% ( OR=0.84, 95%CI =0.80-0.88), 9% ( OR=0.91, 95%CI =0.82- 0.99 ), and 15% ( OR=0.85, 95%CI =0.77-0.94), respectively （P <0.05). Conclusions The time of MVPA and SLP are seriously insufficient among children aged 8-9 years in Pudong New Area. There is an association between physical activity levels and metabolic syndrome as well as its components. Increasing the time of MVPA and SLP is of great significance for maintaining a relatively low risk of metabolic syndrome in children.

Objective To explore the association between psychological resilience and internet addiction among senior primary school students,so as to provide a scientific basis for formulating strategies for preventing internet addiction and enhancing psychological resilience in this group.Methods A stratified cluster sampling method was employed.In May 2021,a total of 1 618 fourth-and fifth-grade students from 5 primary schools in Jiading District,Shanghai were surveyed on psychological resilience and internet addiction through questionnaires.Independent sample t-tests,chi-square tests,and Logistic regression models were used for data analysis.Results Among the 1 618 students,the prevalence rate of internet addiction was 8.8%(142 students).The total score of psychological resilience(t=6.215,P<0.001)and the scores of three dimensions,namely family support(t=3.509,P<0.001),goal focus(t=6.965,P<0.001),and positive perception(t=5.887,P<0.001),of those reported with internet addiction were all significantly lower than those without internet addiction.Multivariate logistic regression analysis showed that compared with individuals with low psychological resilience,those with moderate(aOR=0.395,95%CI:0.267-0.584,P<0.001)and high psychological resilience(aOR=0.167,95%CI:0.077-0.365,P<0.001)had a lower probability of internet addiction.The three sub-dimensions of psychological resilience,namely goal focus,positive perception and family support,also showed a statistically significant negative association with internet addiction in these students.Conclusion Nearly one-tenth senior primary school students in Jiading District self-reported internet addiction.Higher levels of psychological resilience were associated with a lower probability of internet addiction among senior primary school students.Focusing on enhancing the goal focus,positive perception and family support dimensions in psychological resilience may be of great significance for preventing internet addiction among senior primary school students.

Objective To assess the dietary quality of preschool children and explore the relationship between feeding practices and dietary quality.Methods Relying on the Shanghai Maternal-Child Pairs Cohort,3 177 preschool children were selected as the subjects for this study,and questionnaire were surveyed on their dietary intake and feeding practice.The diet balance index was used to evaluate dietary quality among preschool children.High bound score(HBS),the low bound score(LBS),and the dietary quality distance(DQD)were calculated to respectively reflect overall dietary overconsumption,insufficiency,and imbalance.Logistic regression was utilized to analyze the association between feeding practice and dietary quality in preschool children.Results The HBS,LBS,and DQD of the subjects were 2(0,8),22.19±10.80,and 26.78±9.57,respectively.Only 7.68%of the children had a balanced dietary intake,with 74.73%and 33.99%of overall dietary intake being inadequate and excessive,respectively.Parental perceived weight were negatively associated with the risk of moderate to high over intake among children(aOR=0.79,95%CI:0.63-0.98).The higher the perceived responsibility(aOR=1.19,95%CI:1.03-1.37)score,the lower the monitoring score(aOR=0.83,95%CI:0.74-0.93),and the higher the likelihood that the child had a moderate to high under intake.The scores of pressure to eat were also positively correlated with the risks of under intake and moderate to high overall unbalance in preschool children(aOR=1.15-1.39,95%CI:1.02-1.63).Conclusion Preschool children commonly experience dietary imbalance,with inadequate and excessive intake coexisting.Parental perceived weight and monitoring were positively associated with preschoolers'dietary quality,whereas perceived responsibility and pressure to eat were negatively associated with it.

Objective: To develop the Daily Stressor Evaluation Questionnaire for Primary School Students and to evaluate the reliability and validity of the questionnaire. Methods: In November 2020, a convenience sampling method was used to conduct semi structured interviews with 10 primary school students in Jiading District, Shanghai. Through literature review, semi structured interviews, and expert consultation, 59 question items were developed, and 138 elementary school students in 2 districts in Shanghai were selected for a pre survey in March 2021, and the formal questionnaire was formed after item screening and parallel analysis. Stratified cluster sampling was used to survey a total of 1 618 fourth and fifth grade students enrolled in five elementary schools in Jiading District, Shanghai from April to May, 2021, to further test the reliability of the questionnaire. Results: The Daily Stressor Evaluation Questionnaire for Primary School Students contained 4 dimensions and 22 items in total. The internal consistency test showed that cronbach α coefficient of the questionnaire was 0.904 and Cronbach α coefficient of each dimension was between 0.689 to 0.803. The Guttman split half reliability was 0.885 and ranged from 0.582 to 0.732 for each dimension. The results of the validation factor analysis showed that the χ 2/df of the questionnaire was less than 4, the root mean square error of approximation was less than 0.08, and the Tueker Lewis index and comparative fit index were above 0.80. The critical value of using the ROC curve to evaluate the questionnaire was 31 points. At this point, the area under the curve was determined to be 0.783, while the sensitivity and specificity were found to be 71.43% and 73.39%, respectively. Additionally, the positive predictive value and negative predictive value were calculated to be 23.26% and 95.79%, respectively. Conclusion The Daily Stressor Evaluation Questionnaire for Primary School Students developed in this study has good reliability and validity and can be used as an assessment tool for evaluating stressors in primary school students.