Screen time and health issues in Chinese school-aged children and adolescents: a systematic review and meta-analysis

Screen exposure, mental health and emotional well-being in the adolescent population: is it time for governments to take action

During the last decade, a multitude of epidemiological studies with different designs have been published assessing the association between the use of digital media and psychological well-being, including the incidence of mental disorders and suicidal behaviours. Particularly, available research has very often focused on smartphone use in teenagers, with highly addictive potential, coining the term 'problematic smartphone use' and developing specific scales to measure the addictive or problematic use of smartphones. Available studies, despite some methodological limitations and gaps in knowledge, suggest that higher screen time is associated with impaired psychological well-being, lower self-esteem, higher levels of body dissatisfaction, higher incidence of eating disorders, poorer sleeping outcomes and higher odds of depressive symptoms in adolescents. Moreover, a significant association has also been found between screen time and higher suicide risk. Finally, problematic pornography has been shown to be highly prevalent and it is a strong cause of concern to many public health departments and national governments because it might be eventually associated with aggressive sexual behaviours.

Replacing screen time, with physical activity and sleep time: influence on cardiovascular indicators and inflammatory markers in Brazilian children

OBJECTIVE

To examine if the substitution of different screen time intervals with light physical activity (LPA), moderate to vigorous physical activity (MVPA) and sleep is associated with cardiovascular indicators and inflammatory markers in children.

METHODS

This is a cross-sectional study developed with 186 children aged between six and 11 years old from public schools in southern Brazil. CRF was measured with the 6-minute running and walking test, following the Brazil Sports Project procedures. The percentage of fat was evaluated through DXA. LPA and MVPA were measured using accelerometers. Sleep and screen time were assessed by questionnaires answered by parents. Leptin and C-reactive protein were measured by fasting blood collection. Systolic and diastolic blood pressure were determined through a digital sphygmomanometer. Isotemporal substitution models were used for statistical analysis.

RESULTS

Replacing 1 h of screen time with MVPA was associated with lower BMI, systolic and diastolic blood pressure, fat percentage, leptin, and C-reactive protein. When screen time was substituted for sleep time, lower waist circumference was observed. Regarding the substitution of 1 h of screen time with LPA, significant values were found only for leptin.

CONCLUSION

The replacement of screen time with physical activities of different intensities and sleep time was associated with benefits in cardiovascular indicators and inflammatory markers in childhood.

Evaluation of physical fitness and health of young children aged between 3 and 6 based on cluster and factor analyses

BACKGROUND

As life improves and sedentary time increases, young children's physical fitness gradually declines.

METHODS

Multi-stage stratified whole cluster sampling was utilized to sample 5584 preschoolers. Young infants' morphology, function, and quality were revealed using cluster and factor analysis.

RESULTS

The cluster analysis separated 3-6-year-olds into two genders: 1,551 men in group A "high physical fitness" 1,499 men in group B "low physical fitness"; 1,213 women in group A and 1,321 women in group B. Young children's fitness was measured by standing long jump(1.00), weight(1.00), and height(1.00). A cluster analysis of 3-4-year-olds classified them into three groups: 272 "muscular strength," 75 "average physical fitness," and 250 "low agility." Young children's health depends on weight (1.00), height (0.57), and chest circumference (0.54). A cluster analysis of the 4-5-year-olds classified them into two groups: 1070 "balance" and 806 "muscular strength." Young children's health depends on weight (1.00), height (0.74), and chest circumference (0.71). A cluster analysis of the 5-6-year-olds divided them into three groups: 1762 "high physical fitness," 384 "obese," and 105 "low physical fitness." Young children's physical health depends on BMI (1.00), weight (1.00), and chest circumference (1.00). Factor analysis demonstrated that muscle strength, body shape, cardiovascular variables, and physical fitness composite components affected young children's health.

CONCLUSION

Women should focus on motor function and strength, while men on flexibility. Male group B "low physical fitness" should focus on strength, motor function, and balance, whereas male group A "high physical fitness" should focus on flexibility. Then, female group A "high physical fitness" should emphasize variety.2) For 3-4-year-olds, group A "muscular strength" should focus on flexibility, and group C "low agility" on motor function. 3) For 4-5-year-olds, group A "balanced" should focus on strength and motor function; 4) For 5-6-year-olds, group B "obese" should emphasize weight loss, and group C "low fitness" should emphasize strength, motor function, and flexibility; 5) Young children's physical fitness depends on muscle strength, body shape, cardiovascular factors, and physical fitness composite.

An umbrella review of the benefits and risks associated with youths' interactions with electronic screens

The influence of electronic screens on the health of children and adolescents and their education is not well understood. In this prospectively registered umbrella review (PROSPERO identifier CRD42017076051 ), we harmonized effects from 102 meta-analyses (2,451 primary studies; 1,937,501 participants) of screen time and outcomes. In total, 43 effects from 32 meta-analyses met our criteria for statistical certainty. Meta-analyses of associations between screen use and outcomes showed small-to-moderate effects (range: r = -0.14 to 0.33). In education, results were mixed; for example, screen use was negatively associated with literacy (r = -0.14, 95% confidence interval (CI) = -0.20 to -0.09, P ≤ 0.001, k = 38, N = 18,318), but this effect was positive when parents watched with their children (r = 0.15, 95% CI = 0.02 to 0.28, P = 0.028, k = 12, N = 6,083). In health, we found evidence for several small negative associations; for example, social media was associated with depression (r = 0.12, 95% CI = 0.05 to 0.19, P ≤ 0.001, k = 12, N = 93,740). Limitations of our review include the limited number of studies for each outcome, medium-to-high risk of bias in 95 out of 102 included meta-analyses and high heterogeneity (17 out of 22 in education and 20 out of 21 in health with I2 > 50%). We recommend that caregivers and policymakers carefully weigh the evidence for potential harms and benefits of specific types of screen use.

Adolescent Screen Use: Problematic Internet Use and the Impact of Gender

OBJECTIVE

The relationship between screen use and problematic internet use (PIU; i.e., internet addiction) amongst adolescents has not been sufficiently explored. Further, there is even less research on how gender is associated with this relationship. The goal of the study was to examine adolescent screen use, PIU, and its impact on day-to-day routines of adolescents.

METHODS

Participants were recruited from an outpatient pediatric clinic in São Paulo, Brazil. A total of 180 adolescents completed questionnaires related to their screen use, extracurricular activities, and symptoms of PIU. Univariate and multivariate statistics were used to determine correlates and predictors of PIU, and to explore gender differences.

RESULTS

A total of 26.1% of adolescents met the criteria for PIU. There were no significant differences between boys and girls in PIU severity. However, there were significant gender differences in preferred use of the Internet, with boys being more likely to access the Internet to play video games (odds ratio [OR]=27.1) and girls being more likely to socialize with friends (OR=4.51). PIU severity increased proportionally to the number of hours of use of all screen devices with moderate-to-large effect sizes (η2=0.060-0.157). Using screens during meals and missing extracurricular activities were both associated with PIU.

CONCLUSION

Though gender was not associated with PIU, both excessive use of screen devices during meals and neglect of offline extracurriculars activities were identified as risk factors for PIU. Prevention measures should consider the impact of gender and associated patterns of motivation and Internet use.

Prospective associations between adherence to 24-hour movement guidelines and mental well-being in Chinese adolescents

Most evidence regarding the relationships between adherence to 24-hour movement guidelines and adolescent mental health have been derived from cross-sectional studies or have ignored positive mental health indicators. The current prospective study examined the associations between adherence to 24-hour movement guidelines and changes in mental well-being among Chinese adolescents over three months. 816 Chinese adolescents (Mage = 14.76 years; SD = 0.81) completed baseline and follow-up scales of 24-hour movement behaviours, mental well-being, and covariates. Linear mixed-effects models were used for data analyses, with adjustments for covariates and mental well-being at baseline. There was a significant improvement in mental well-being across the three months, and the improvement in mental well-being was positively associated with meeting any single guidelines and both physical activity and sleep guidelines but not adherence to all three guidelines. Meeting both physical activity and sleep recommendations appears to exert more significant benefits on mental well-being than meeting one or two other recommendations. An integrative approach to mental health promotion by focusing on 24-hour movement behaviours (at least physical activity and sleep) may be more effective than focusing on a single behaviour alone.

Advances in myopia prevention strategies for school-aged children: a comprehensive review

Myopia has significantly risen in East and Southeast Asia, and the pathological outcomes of this condition, such as myopic maculopathy and optic neuropathy linked to high myopia, have emerged as leading causes of irreversible vision loss. Addressing this issue requires strategies to reduce myopia prevalence and prevent progression to high myopia. Encouraging outdoor activities for schoolchildren and reducing near-work and screen time can effectively prevent myopia development, offering a safe intervention that promotes healthier habits. Several clinical approaches can be employed to decelerate myopia progression, such as administering low-dose atropine eye drops (0.05%), utilizing orthokeratology lenses, implementing soft contact lenses equipped with myopia control features, and incorporating spectacle lenses with aspherical lenslets. When choosing an appropriate strategy, factors such as age, ethnicity, and the rate of myopia progression should be considered. However, some treatments may encounter obstacles such as adverse side effects, high costs, complex procedures, or limited effectiveness. Presently, low-dose atropine (0.05%), soft contact lenses with myopia control features, and orthokeratology lenses appear as promising options for managing myopia. The measures mentioned above are not necessarily mutually exclusive, and researchers are increasingly exploring their combined effects. By advocating for a personalized approach based on individual risk factors and the unique needs of each child, this review aims to contribute to the development of targeted and effective myopia prevention strategies, thereby minimizing the impact of myopia and its related complications among school-aged children in affected regions.

Objective Evaluation of Active Interactions between the Operator and Display Screen Equipment Using an Innovative Acquisition System

The occupational risk of operators using display screen equipment (DSE) is usually evaluated according to the extent of time spent in active operator-DSE interactions. Risk assessment is based on activity data collected through questionnaires. We evaluated an original and innovative system that can objectively assess active operator-DSE interactions by collecting electrical impulses generated by the activation of mouse, keyboard and a camera that collects attentive eye-screen fixation. The main aim of this study was to evaluate the system's performance on an employee sample involved in the task of active reading and copying at a DSE workstation connected to the system. In the context of mandatory health surveillance at work, we enrolled 38 DSE operators with normal neuropsychological and eye assessments who were required to complete two predefined reading and writing tasks. The obtained results show that the system is able to collect activity data derived from operator-DSE interactions through screen fixation, keyboard tapping and mouse handling. In the copying task, the session duration as recorded by the system was highly related to the screen fixation time. In the copying task, mouse and keyboard activities were more strongly related to session duration than screen fixation. For the copying task, it was also possible to obtain individual profiles of operator-DSE interactions while performing the same standardized tasks. Collected data can allow an objective evaluation of active time spent by DSE operators at their workstations, thus allowing a more accurate occupational health risk assessment and management. Prospective analysis of individual operator-DSE interaction profiles can favor the setup of targeted preventive and organizational interventions from an of even wider worker wellbeing perspective.

Combinations of physical activity, screen time and sleep, and their association with subjective wellbeing in children

BACKGROUND

Subjective wellbeing is an important indicator of health outcomes in children. 24-hour movement behaviours (i.e., physical activity, sedentary behaviour, sleep and their combination), a set of modifiable lifestyle behaviours, have been demonstrated to be associated with subjective wellbeing. Thus, the aim of this study was to investigate the relationship between the compliance of the 24-h movement guidelines and subjective wellbeing in a sample of Chinese children.

METHODS

Cross-sectional data from primary and secondary school students in Anhui Province, China were used for the analysis. A total of 1098 study participants (mean age: 11.6 years, body mass index: 19.7 ± 2.9) were included, of which 51.5% were boys. Physical activity, screen time, sleep, and subjective wellbeing were measured using validated self-reported questionnaires. Multivariable logistic regression analysis was used to assess the relationships between the compliance of different combinations of 24-h movement guidelines and subjective wellbeing in participants.

RESULTS

The compliance of (i.e., physical activity recommendations, screen time recommendations and sleep recommendations) 24-h movement guidelines was associated with better subjective wellbeing (OR: 2.09; 95CI%: 1.01-5.90) compared to the compliance of none of the guidelines. Furthermore, there was a dose-response relationship between the number of guidelines met (3 > 2 > 1 > 0) and improved subjective wellbeing (p < 0.05). Despite some exceptions, there was a significant relationship between the compliance of different combinations of the guidelines and better subjective wellbeing.

CONCLUSION

This study found that the compliance of 24-h movement guidelines was associated with greater subjective wellbeing in Chinese children.

The association between meeting physical activity guidelines and academic performance among junior high school adolescents in China-evidence from the China education tracking survey

Purpose

To examine how well Chinese adolescents meet the physical exercise time and screen time recommendations in the Physical Activity Guidelines for Chinese Residents (2021), and the relationship between adolescents' physical exercise time, screen time and their academic performance.

Method

Daily physical exercise time, screen time and academic performance were collected from Grade 8 adolescents (n = 9,449). Academic performance included standardized scores on Chinese, Math and English tests and responses to the School Life Experience Scale.

Results

Meeting the physical activity time and screen time in the Physical Activity Guidelines for Chinese Residents was associated with adolescents' academic performance. Specifically, having at least 60 min of physical exercise per day was associated with adolescents' school life experiences compared to adolescents who did not meet the physical exercise time and screen time in the Chinese Residents' Physical Activity Guidelines. Less than 2  h of cumulative screen time per day was associated with adolescent mathematics test scores, English test scores and school life experiences. Meeting both physical exercise time and screen time to be recommended had more significant effects on adolescents' mathematics, Chinese, English and school life experiences. Meeting both the physical exercise time and screen time recommendations in the Physical Activity Guidelines for Chinese Residents was more significantly associated with boys' mathematics test scores, Chinese test scores and School life experience. Meeting both the physical exercise time and screen time requirements in the Physical Activity Guidelines for Chinese Residents had a more significant effect on School life experience for girls.

Conclusion

Physical exercise participation of at least 60 min per day and/or less than 2  h of cumulative screen time per day were both associated with adolescent academic performance. Stakeholders should actively promote adolescents to follow the Physical Activity Guidelines for Chinese Residents (2021).

Screen time and its correlates among children aged 3–10 years during COVID-19 pandemic in Nepal: a community-based cross-sectional study

Objective

This study aims to determine the prevalence of high screen time among schoolchildren aged 3–10 years in Bhaktapur, its correlates and the parents’ strategies to reduce screen time during the COVID-19 pandemic in Nepal.

Methods and analysis

This cross-sectional descriptive study was conducted during March 2021. A total of 630 households were selected for the study from 21 randomly selected clusters in Bhaktapur, Nepal. Correlates of high screen time were determined using a logistic model. P<0.002 was taken as significant.

Results

Among all the participants, the mean (SD) age was 7.0 (2.2) years, with 50.3% male participation. Few participants had online classes (n=24, 3.8%). The prevalence of high screen time among the participants was very high (55.2%, 95% CI=51.3% to 59.1%), which is even higher in boys (61.8%, 95% CI=58.0% to 65.6%). The median screen time before the COVID-19 pandemic was 1.0 hours (mean rank=275.8) which increased to 2.2 hours (mean rank=116.6) during the pandemic (p<0.001). Participants having smartphones were about seven times (adjusted OR=6.9, 95% CI=1.5 to 31.3, p=0.013) more likely to have high screen time than those who did not have the device. Most parents used to reprimand and urge their children to play outside to limit their screen usage.

Conclusion

During the COVID-19 pandemic, about one in two schoolchildren of 3–10 years had higher screen time than before the COVID-19 pandemic. Parents’ strategies to reduce screen time were not effective. An intervention study is recommended to design and test effective strategies to reduce screen time and its negative effects on children’s health.