Objective: To explore the longitudinal correlation between smartphone multitasking and depressive symptoms, so as to provide an evidence based basis for promoting the mental health of college students. Methods: A total of 967 college students were recruited from one university in Taiyuan, Chongqing, and Shenzhen cities, China, by using multi stage randomized cluster sampling from October to December 2021 at baseline, and a follow up survey was conducted in May 2022. Smartphone multitasking behaviors were assessed by means of the Assessment of Smartphone Multitasking for Adolescents (ASMA), and depressive symptoms were assessed using the Patient Health Questionnaire-9 (PHQ-9) among college students. Chi square tests were performed to compare the differences in depressive symptoms between different groups of demographic characteristics, and binary Logistic regression models were employed to analyze the associations between smartphone multitasking and depressive symptoms among college students. Results: The rates of depressive symptoms among college students at baseline and follow up were 35.2% and 42.3%, respectively. Compared to the low level smartphone multitasking index group at baseline, the moderate and high level groups were more likely to experience depressive symptoms at baseline (moderate level group: OR=1.74, 95%CI =1.22-2.50, high level group: OR=2.77, 95%CI =1.94-3.95) and followup (moderate level group: OR=1.41, 95%CI =1.01-1.95, high level group: OR=1.64, 95%CI =1.17-2.29) ( P <0.05). In addition, compared to the persistently low smartphone multitasking index, increased risk of depressive symptoms was associated with maintaining a moderate to high ( OR=2.94, 95%CI =1.83-4.71), and a higher ( OR=2.07, 95%CI =1.31-3.27) or lower smartphone multitasking index ( OR=2.02, 95%CI =1.27-3.19) ( P <0.05). Moreover, higher smartphone multitasking index scores were positively associated with the risk of new-onset depressive symptoms at follow up ( OR=1.87, 95%CI=1.07-3.27, P <0.05). Conclusions Smartphone multitasking behaviors are find to be associated with an increased risk of depressive symptoms in college students. There is a need to reduce smartphone multitasking in order to decrease depressive symptoms and promote students mental health.

Objective: To elucidate the association between biorhythm disorders and health risk behaviors in adolescence, so as to provide reference for appropriate interventions. Methods: From March to April 2023, 2 381 adolescents in Shanghai were selected as research objects using convenience sampling and stratified random cluster sampling methods. The Self rating Questionnaire of Biological Rhythm Disorders for Adolescents (SQBRDA) and the self report health risk behaviors questionnaire were used to investigate the status of adolescent biorhythm disorders and nine kinds of health risk behaviors, while a multivariate Logistic regression model was employed to analyze the association between the two variables. Results: The average SQBRDA score was (68.25±0.42) The incidence and detection rates of health risk behaviors in the groups with no co occurrence, mild co occurrence, moderate co occurrence, and severe co occurrence were 234(9.83%), 1 176(49.39%), 830(34.86%) and 141(5.92%), respectively. The total SQBRDA score was positively correlated with the risk of co occurrence of health risk behaviors. The risk of mild co occurrence, moderate co occurrence, and severe co occurrence of health risk behaviors was 9.05 times (95% CI =4.25-19.15, P <0.01), 44.55 times (95% CI =20.75-96.05, P <0.01) and 110.05 times (95% CI =40.65-297.95, P <0.01) higher, respectively, among adolescents with higher scores of biorhythm disorders compared to adolescents with lower scores of biorhythm disorders. Conclusions Health risk behaviors among adolescents in Shanghai draw attention to a serious phenomenon whereby biorhythm disorders are positively correlated with the risk of co occurrence. Comprehensive interventions aimed at addressing adolescent health risk behaviors should focus on regulating biorhythm disorders.

Objective: To explore the association among neck-shoulder pain (NSP), low back pain (LBP) and co occurring symptoms with mental sub health in adolescents, so as to provide evidence for improving physical and mental health of adolescents. Methods: Stratified cluster random sampling method was used to select 7 986 students from 12 middle and high schools in Shenzhen, Nanchang, and Shenyang cities from October to December 2019. The Assessment of Spinal Health of Youth (ASHY) and the Brief Instrument on Psychological Health of Youth (BIOPHY) were used to assess NSP, LBP and mental sub health. Binary Logistic regression model was used to analyze the association between NSP, LBP and co occurring symptoms with mental sub health in adolescents. Results: The detection rates of adolescents with NSP, LBP and co occurring symptoms and mental sub health were 9.1% , 9.8%, 9.5%, and 10.0%, respectively. The co occurring rate of neck shoulder pain, low back pain and mental sub health was 3.2%. After adjusting for confounding variables such as gender, age, being an only child, family residence, and parental education level, NSP ( OR=6.01, 95%CI =5.02-7.19), LBP ( OR=5.08, 95%CI =4.25-6.07), and co occurring symptoms ( OR= 5.96 , 95%CI =4.98-7.12) in adolescents were positively correlated with mental sub health risk ( P <0.01). Stratifying the gender, boys with NSP, LBP and co occurring symptoms ( OR =6.84, 5.80, 6.74)had a higher risk of mental sub health compared to girls ( OR =5.52, 4.65, 5.49) ( P <0.01). Conclusions NSP, LBP and co occurring symptoms in adolescents are associated with mental sub health. The mental health status of boys is more affected by NSP, LBP and their co occurring symptoms. Measures should be taken to improve spinal health in adolescents to reduce the incidence of mental sub health.

Objective: To describe the prevalence and association of dietary rhythm and depressive symptoms among adolescents, so as to provide a basis for improving unhealthy behavioral habits,and to promote adolescent physical and mental health. Methods: From October to December 2021, a total of 22 868 students were selected from one middle school and high school in urban and rural areas of eight cities, namely, Shenyang, Xuzhou, Shenzhen, Taiyuan, Nanchang, Zhengzhou, Chongqing, and Kunming cities, China, using a combination of purposive sampling and stratified cluster random sampling. A self administered questionnaire was used to assess adolescents dietary rhythm, and the Patient Health Questionnaire-9 (PHQ-9) was used to assess depressive symptoms. Binary Logistic regression model was employed to analyze the associations between adolescent dietary rhythm and depressive symptoms, while the associations between adolescent dietary rhythm and depressive symptoms across gender and physical activity levels were stratified by gender and physical activity levels. Results: The detection rate of depressive symptoms in adolescents was 44.4%. The respective differences in the detection rates of depressive symptoms among adolescents of different genders, physical activity levels, and dietary rhythm disorders were statistically significant ( χ 2=157.51, 105.02, 3 282.50, P <0.01). Taking the low disordered dietary rhythm group as the reference, binary Logistic regression analyses showed that after adjusting for confounding factors such as age, gender，family location, family economic situation, whether only child, parental education level, and learning burden, physical activity levels, depressive symptoms were positively correlated with adolescents in the moderate disordered dietary rhythm group ( OR=2.63, 95%CI =2.45-2.83) and the high disordered dietary rhythm group ( OR=6.38, 95%CI = 5.93- 6.86). In addition, after stratifying by gender, dietary rhythm were positively correlated with depressive symptoms. The moderate disordered group (male: OR=2.62, 95%CI =2.37-2.89, female: OR=2.67, 95%CI =2.40-2.97) and the highly disordered group (male: OR=5.74, 95%CI =5.19-6.35, female: OR=7.11, 95%CI =6.40-7.89) were positively correlated with depressive symptoms. After stratification by physical activity levels, low, moderate and above physical activity levels among adolescents in the disordered dietary rhythm group (low physical activity: OR=2.91, 95%CI =2.58-3.29, moderate and above physical activity: OR= 2.50, 95%CI =2.28-2.74), high disordered group (low physical activity: OR=6.51, 95%CI =5.94- 7.13 , moderate and higher physical activity: OR=6.18, 95%CI =5.47-6.97) were positively associated with depressive symptoms ( P <0.01). There was an interaction between dietary rhythm and physical activity levels in regard to the development of depressive symptoms in adolescents, taking the group with moderate and above physical activity levels and low disordered dietary rhythm as the reference,the detection rate of which was higher in adolescents with low levels of physical activity and those in the moderate or high disordered dietary rhythm group ( OR=1.50, 3.90, 95%CI=1.39-1.61, 3.63-4.19, P <0.01). Conclusions Dietary rhythm disorders were found to be positively associated with depressive symptoms in adolescents. Regular dietary behaviors and increased physical activity play an important positive role in promoting adolescent mental health.

Abstract The roles of social and environmental factors in psychological and behavioral problems among children and adolescents have been repeatedly demonstrated, and the relationship between the natural environment and mental health has received increasing attention. On the basis of research on the relationships of social and natural environmental factors and psychological with behavioral problems in children and adolescents, the article attempts to unravel the compound health effects of these factors on psychological and behavioral problems, and proposes research directions to promote research and interventions regarding risk factors for psychological and behavioral problems arising from co-exposure to social and natural environmental factors among children and adolescents.

Objective: To analyze the association between non-school sedentary time and myopia among primary and secondary school students with different levels of physical activity, so as to provide data for precise measures to prevent and control myopia. Methods: From September to December 2019, stratified cluster sampling was used to select 7 872 primary and secondary students in grades 4 to 12, middle and high school students from Hefei, Suzhou, Chizhou and Wuhu Cities in Anhui Province. Face-to-face questionnaires and vision examinations were conducted to collect demographic information, physical activity time, sedentary study time and visual health status. Potential categories were analyzed for different types of physical activity time, and Logistic regression was used to assess the relationship between non-school sedentary time and myopia at different levels of physical activity. Results: A total of 2 976 primary and secondary school students were found with high physical activity levels and 4 896 primary and secondary school students with low physical activity levels. The proportion of low physical activity was higher in girls than in boys (68.7% vs . 55.6%), and the differences were statistically significant ( χ 2=143.97, P <0.01). The overall screening myopia rate was 48.2%, with statistically significant differences among female students (53.0%) compared with male students (43.3%), urban students ( 51.8 %) compared with rural students (44.5%), and longer non-school sedentary time students (60.6%) compared with average (45.1%) and shorter (42.1%) non-school sedentary time students, and the differences were statistically significant ( χ 2=73.15, 41.96 , 161.74, P <0.01). Adjusting for confounders such as residence, grade, gender, age, father s education, mother s education, and body mass index (BMI), multivariate Logistic regression analysis revealed that prolonged after-school sedentary study was positivety correlated with myopia among primary and secondary school students of low physical activity levels ( OR=1.52, 95%CI=1.27-1.83, P <0.01), and there was no statistical association between after-school sedentary time and myopia in primary and secondary school students with high physical activity levels ( P >0.05). Conclusion Attention should be paid to non-school sedentary time for primary and secondary school students with low physical activity levels. And students who spend a lot of time sitting outside of school should be encouraged to maintain high physical activity levels to reduce the risk of myopia.

Abstract With the socio economic development and urbanization, obesity increased dramatically worldwide among children and adolescents over the past years. The determinants of obesity are complicated, and its association with built environment in community has received great concern in recent years. To provide theoretical basis for building supportive environment beneficial for obesity prevention, the review summarizes obesity related built environment, including food environment, physical activity environment, road traffic environment, lighting at night.

Objective: To develop the Assessment of Smartphone Multitasking for Adolescents (ASMA) and evaluate its reliability and construct validity, so that to provide an evaluation tool for relevant epidemiological studies. Methods: Based on literature review, expert based judgement, and group discussion, the self administered ASMA identified 3 dimensions named smartphone activities and non-media activities multitasking, smartphone activities and other media activities multitasking, and smartphone functional use multitasking, which initially included 27 items. From October to December 2021, 5 566 college students were selected from 7 regions, including Liaoning, Shanxi, Henan, Shanghai, Chongqing, Shenzhen, and Yunnan by multi stage cluster sampling method, and item analysis, factor analysis, and reliability evaluation were used to screen items and evaluate reliability and validity. Results: The final version of AMSA contained 3 dimensions covering 26 items. The variance cumulative contribution rate was 59.63 %. The internal consistency test showed that Cronbach s alpha coefficient for the questionnaire was 0.944, and ranged from 0.838 to 0.928 for each dimension. The split half coefficient of the questionnaire was 0.849 and ranging from 0.781 to 0.874 for each dimension. The results of confirmatory factor analysis showed that the root mean square error of approximation (RMSEA), comparative fit index (CFI), and Tucker Lewis index (TLI) of the questionnaire were 0.068, 0.901, and 0.891, respectively, which had which had a good fitting degree. The results of Pearson correlation analysis showed that the criterion validity of the questionnaire was good ( r=0.206-0.351, P <0.01). Conclusion The ASMA is consistent with the evaluation standard of psychometrics and can be used as an assessment tool to evaluate smartphone multitasking behaviors in adolescents.

Objective: To develop a simplified Rating Questionnaire of Social Ecological Risks in Adolescents and to evaluate the reliability and predictive validity of the brief questionnaire, so as to provide data and evidence support for building the evaluation system of cumulative social ecological risk exposure. Methods: A large cross sectional was conducted in eight areas, including Shenzhen, Zhengzhou, Xuzhou, Nanchang, Shenyang, Taiyuan, Kunming and Chongqing, from October to December 2021. A total of 22 868 adolescents were included in the analysis. Data on healthy behaviors from 10 838 adolescents from Shenyang, Taiyuan, Kunming, Chongqing were used for item selection, based on factor analysis, validity and reliability evaluation. The data from Shenzhen, Zhengzhou, Xuzhou, Nanchang, including 12 030 adolescents, were used to define the partition values of the brief questionnaire, and evaluate the predictive validity. Results: The brief questionnaire containing 25-item were developed by analyzing and choosing all items of original questionnaire, and covered seven dimensions including individual, family, school, community, policy, time and culture. The cumulative contribution rate of variance was 54.95%, the Cronbach coefficient was 0.79, and the split half coefficient was 0.70. Participants in the higher risk group had significantly higher risk of smoking ( OR =4.05, 95% CI = 2.78 -5.92), drinking ( OR =3.47, 95% CI =2.86-4.19), suicidal ideation ( OR =8.85, 95% CI =7.68-10.21), suicidal plans ( OR = 8.85, 95% CI =7.27-10.78), suicidal attempt ( OR = 8.86 , 95% CI =6.67-11.78) than individual in the lower risk group ( P < 0.05). After stratified by gender, the above positive correlations still remained significant( P <0.05). Conclusion The brief questionnaire, with good reliability and predictive validity, could be widely applicated in the further researches on social ecological risk factors.

Objective: To analyze the association between eye use behavior and self reported myopia in middle and high school students, and provide the scientific basis for the prevention and control of myopia. Methods: A total of 14 872 middle and high school students was selected from four provinces and cities from December 2015 to March 2016, including Jiangxi(Nanchang,Yintan,Dexing), Liaoning(Shenyang), Guangdong(Shenzhen), Henan(Zhengzhou) provinces. A self administrated questionnaire was used to collect the basic information, self reported myopia and eye use behaviors among middle and high school students. The Chi square tests were applied to compare the differences in self reported myopia among middle and high school students with different characteristics. Multivariate binary Logistic regression models were used to analyze the association between eye use behavior and self reported myopia in middle and high school students. Results: The self reported myopia rate of middle and high school students was 68.5%, with 59.7% and 78.6% for junior high school students and senior high school students, respectively. After adjusting for the potential confounders, the Logistic regression models showed that middle and high school students who read and write with their heads down ( OR =1.94, 2.32),middle and high school students who lie down or lie on stomach when using their eyes ( OR =1.27, 1.28) had a higher risk of self reported myopia ( P <0.01). There was a negative correlation between eye use distance (reading and writing distance, distance from eyes to TV, mobile phone, or tablet) and self reported myopia ( OR =0.73, 0.70, 0.81; 0.61, 0.66 , 0.76) in middle and high school students ( P <0.01). In addition, the risk of self reported myopia was lower in middle school students with longer eye to computer distance ( OR=0.77, P <0.01). Conclusion There is a significant association between eye use postures, eye use distance and self reported myopia in middle and high school students. Health education for the risk and behavior factors of myopia should be actively promoted to ensure the visual health of children and adolescents.