The reciprocal relationship between body mass index categories and physical fitness: a 4‐year prospective cohort study of 20 000 Chinese children

Introduction: Body mass index (BMI) categories and physical fitness are associated but the reciprocal relationship between BMI categories and physical fitness has not been investigated. This study aims to investigate the longitudinal reciprocal relationship between BMI categories and physical fitness. Methods: This is a population-based 4-year cohort study in 48 elementary schools. Children aged 6 to 9 years at recruitment were included. BMI categories and physical fitness including handgrip strength, core muscle endurance, flexibility, and cardiorespiratory fitness were measured using standard equipment and protocol. Results: Among 26 392 eligible participants, 19 504 (73.9%) were successfully followed for 3 years. Baseline obesity prevalence was 5.9%. After 3 years, those who were unfit at baseline had an increased risk of obesity (risk ratio [RR] 1.41, 95% CI 1.16-1.71, P < .001) and those who were fit at baseline had a decreased risk of obesity (RR 0.69, 95% CI 0.60-0.80, P < .001) compared with moderately fit children. Furthermore, improvement of fitness predicted decreased risk of obesity. Similarly, normal body weight also predicted better physical fitness. The path analysis confirmed a strong reciprocal relationship between physical fitness and obesity. Conclusions: Better physical fitness was prospectively associated with normal weight and vice versa. Physically fit children were more likely to maintain a healthy weight and those with a healthy weight were more likely to be physically fit, which is important for healthy development

A mobile game (safe city) designed to promote children's safety knowledge and behaviors: protocol for a randomized controlled trial

Background: Children have high levels of curiosity and eagerness to explore. This makes them more vulnerable to danger and hazards, and they thus have a higher risk of injury. Safety education such as teaching safety rules and tips is vital to prevent children from injuries. Although game-based approaches have the potential to capture children’s attention and sustain their interest in learning, whether these new instructional approaches are more effective than traditional approaches in delivering safety messages to children remains uncertain. Objective: The aim of this study is to test the effectiveness of a game-based intervention in promoting safety knowledge and behaviors among Hong Kong school children in Grades 4-6. It will also examine the potential effect of the game-based intervention on these children’s functioning and psychosocial difficulties. Methods: This study comprises the development of a city-based role-playing game Safe City, where players are immersed as safety inspectors to prevent dangerous situations and promote safety behavior in a virtual city environment. The usability and acceptability tests will be conducted with children in Grades 4-6 who will trial the gameplay on a mobile phone. Adjustments will be made based on their feedback. A 4-week randomized controlled trial with children studying in Grades 4-6 in Hong Kong elementary schools will be conducted to assess the effectiveness of the Safe City game–based intervention. In this trial, 504 children will play Safe City, and 504 children will receive traditional instructional materials (electronic and printed safety information). The evaluation will be conducted using both child self-report and parent proxy-report data. Specifically, child safety knowledge and behaviors will be assessed by a questionnaire involving items on knowledge and behaviors, respectively, for home safety, road safety, and sport-related safety; child functioning will be assessed by PedsQL Generic Core Scales; and psychosocial difficulties will be assessed by the Strength and Difficulties Questionnaire. These questionnaires will be administered at 3 time points: before, 1 month, and 3 months after the intervention. Game usage statistics will also be reviewed. Results: This project was funded in September 2019. The design and development of the Safe City game are currently under way. Recruitment and data collection will begin from September 2020 and will continue up to March 1, 2021. Full analysis will be conducted after the end of the data collection period. Conclusions: If the Safe City game is found to be an effective tool to deliver safety education, it could be used to promote safety in children in the community and upgraded to incorporate more health-related topics to support education and empowerment for the larger public. Trial Registration: ClinicalTrials.gov NCT04096196; https://clinicaltrials.gov/ct2/show/NCT04096196 International Registered Report Identifier (IRRID): PRR1-10.2196/1775

Association of early nutritional status With child development in the Asia Pacific region

Importance: Stunting was used as a proxy for underdevelopment in early childhood in previous studies, but the associations between child development and other growth and body composition parameters were rarely studied. Objective: To estimate the association between malnutrition and early child development (ECD) at an individual level. Design, Setting, and Participants: This population-based, cross-sectional study used data from the East Asia Pacific Early Child Development Scales, a population-representative survey of children aged 3 to 5 years old, conducted in 2012 to 2014 in communities in Cambodia, China, Mongolia, Papua New Guinea, and Vanuatu. Data analysis was performed from November 2019 to April 2021. Exposures: Stunting (height-for-age [HFA] z score less than −2), wasting (weight-for-height z score less than −2), overweight (weight-for-height z score greater than 2), body mass index (BMI)–for-age z score, and body fat proportion based on existing growth standard and formula. Main Outcomes and Measures: ECD directly assessed using the validated East Asia–Pacific ECD Scales. Results: A total of 7108 children (3547 girls; mean [SD], age 4.48 [0.84] years) were included in this study. The prevalence of stunting was 27.1% (range across countries, 1.2%-55.0%), that of wasting was 13.7% (range, 5.4%-35.9%), and that of overweight was 15.9% (range, 2.2%-53.7%). Adjusted for country variations, age, sex, urbanicity, family socioeconomic status, and body fat proportion, ECD was linearly associated with HFA (β, 1.57; 95% CI, 1.35-1.80) and BMI-for-age (β, 0.64; 95% CI, 0.45-0.82). After adjustment for BMI and height, better ECD was associated with low body fat proportion (β, 0.93; 95% CI, 0.45-1.42). The association of HFA was more pronounced in Southeast Asia and the Pacific region than in East Asia, and the association of fat proportion was specific to children living in urban environments. Conclusions and Relevance: HFA, BMI-for-age, and body fat proportion were independently associated with ECD, and these findings suggest that future studies should consider using these parameters to estimate the prevalence of child underdevelopment; nutritional trials should examine to what extent the associations are causal

Age- and sex-specific physical fitness reference and association with body mass index in Hong Kong Chinese schoolchildren

There is lacking a population-based study on the fitness level of Hong Kong schoolchildren, and it seems that increasing childhood obesity prevalence has shifted the classification of healthy fitness, with ‘underfit’ as normal. This cross-sectional territory study aimed to develop an age- and sex-specific physical fitness reference using a representative sample of children aged 6–17 and to determine the associations with body mass index in schoolchildren. The study analyzed Hong Kong School Physical Fitness Award Scheme data covering grade 1 to grade 12 students’ physical fitness and anthropometric measurements from 2017 to 2018. This reference was established without the impact due to COVID-19. Four aspects of physical fitness tests were measured using a standardized protocol, including (i) upper limb muscle strength, (ii) one-minute sit-up, (iii) sit-and-reach, and (iv) endurance run tests. The generalized additive model for location, scale, and shape was used to construct the reference charts. A Mann–Whitney U test was used to compare the mean differences in age, weight, and height, and a Pearson’s chi-square test was used to examine the distributions of sex groups. A Kruskal–Wallis test was used to compare the group differences in BMI status, followed by the Dunn test for pairwise comparisons. A 5% level of significance was regarded as statistically significant. Data of 119,693 students before the COVID-19 pandemic were included in the analysis. The association between physical fitness level and BMI status varied depending on the test used, and there were significant differences in fitness test scores among BMI groups. The mean test scores of the obese group were lower in most of the tests for both boys and girls, except for handgrip strength. The underweight group outperformed the obese group in push-ups, one-minute sit-ups, and endurance run tests, but not in handgrip strength. In conclusion, a sex- and age-specific physical fitness reference value for Hong Kong Chinese children aged 6 to 17 years old is established, and this study demonstrated a nonlinear relationship between BMI status and physical fitness. The reference will help to identify children with poor physical fitness to offer support and guidance on exercise training. It also serves as a baseline for assessing the impact of the COVID-19 pandemic on Hong Kong students’ physical fitness

An Internet quiz game intervention for adolescent alcohol drinking: a clustered RCT

Background and Objectives: Interventions on adolescent drinking have yielded mixed results. We assessed the effectiveness of an Internet quiz game intervention compared to conventional health education. Methods: In this cluster randomized controlled trial with parallel group design, we randomly allocated 30 participating schools to the Internet quiz game intervention or the conventional health education (comparison) group, with 1:1 ratio. Students of Hong Kong secondary schools (aged 12–15 years) were recruited. The intervention was a 4-week Web-based quiz game competition in which participating students answered 1000 alcohol-related multiple-choice quiz questions. The comparison group received a printed promotional leaflet and hyperlinks to alcohol-related information. Results: Of 30 eligible schools, 15 (4294 students) were randomly assigned to the Internet quiz game intervention group and 15 (3498 students) to the comparison group. Average age of participants was 13.30 years. No significant between-group differences were identified at baseline. Overall retention rate for students was 86.0%. At 1-month follow-up, fewer students in the intervention group reported drinking (9.8% vs 12.1%, risk ratio 0.79, 95% confidence interval [CI] 0.68 to 0.92; P = .003), and those who drank reported drinking less alcohol (standardized difference β −0.06, 95% CI −0.11 to −0.01; P = .02). Between-group differences remained statistically significant at 3-month follow-up (10.4% vs 11.6%, risk ratio 0.86, 95% CI 0.74 to 0.999; P = .048; β −0.06, 95% CI −0.11 to −0.01; P = .02). Conclusions: The Internet quiz game intervention reduced underage drinking by 21% at 1-month and 14% at 3-month follow-up compared with conventional health education

Association of harsh parenting and maltreatment with internet addiction, and the mediating role of bullying and social support

Growing evidence has shown that exposure to harsh parenting and child maltreatment elevate the risk of Internet addiction in adolescence. Yet, limited research has examined the mechanisms underlying this association. The present study was a cross-sectional school survey of 1204 adolescents (52.2 % male and 47.8 % female; mean age, 13.36 years) in Hong Kong. The adolescents completed a self-reported questionnaire about their exposure to bullying victimization, bullying perpetration, child maltreatment, Internet addiction, and social support. The findings showed that harsh parenting and maltreatment was significantly associated with Internet addiction. After controlling for a number of confounding factors, the results of the mediation analyses showed that family support and bullying perpetration, and family support and bullying victimization accounted for 36 % and 25 % of the effect of harsh discipline and maltreatment on Internet addiction, respectively. Effective prevention and intervention strategies for Internet addiction should target family and social vulnerabilities in adolescents

Exploring the role of family communication time in the association between family dinner frequency and adolescent psychological distress

Although research shows that family dinner is associated with adolescent psychological well-being, it is unclear whether this association still exists when parent-adolescent communication is limited particularly in today’s high-tech society where frequent family meals may not necessarily co-exist with frequent family communication. We therefore examined the relationships among adolescent psychological distress, parent-adolescent dinner frequency, and parent-adolescent communication time using data from 826 parent-adolescent dyads. Adolescents self-reported symptoms of anxiety, depression, and stress in the preceding month using the validated Chinese version of the Depression Anxiety and Stress Scale – 21 (DASS-21). Their parents reported the frequency of breakfasts and dinners, duration of daily communication with the adolescent, and other family sociodemographic characteristics. Moderated regression analysis was used to examine associations of adolescent psychological distress with parent-adolescent dinner frequency and parent-adolescent non-conflictual communication time. We found that parent-adolescent non-conflictual communication time was independently and significantly associated with adolescent DASS Depression (β = -1.31, p < 0.001), Anxiety (β = -0.84, p < 0.001), and Stress (β = -1.00, p < 0.001) scores, but parent-adolescent dinner frequency was not. Furthermore, adolescents reported lower levels of depression and stress only when they concurrently engaged in both everyday dinner and regular non-conflictual communication with parents. Findings emphasize the importance of regular dinner and non-conflictual communication with parents for adolescent psychological well-being

Mortality among children with Down syndrome in Hong Kong: a population-based cohort study from birth

Objectives: To describe the mortality patterns, comorbidities, and attendance at accident and emergency departments among children with Down syndrome in Hong Kong. Study design: This is a population-based, retrospective cohort study of live births of children with Down syndrome delivered between 1995 and 2014, as identified from territory-wide hospitalization data in Hong Kong. The Kaplan-Meier product limit method was adopted to estimate the survival probabilities of children with Down syndrome by selected demographic and clinical characteristics. Cox regression analyses were conducted to examine associations of comorbidities and accident and emergency department accident and emergency departments attendances with mortality patterns. Results: There were 1010 live births of children with Down syndrome in Hong Kong within the study period and the average rate of live births with Down syndrome was 8.0 per 10 000 live births (95% CI, 6.8-9.30). The rate of live births with Down syndrome over the past 2 decades decreased from 11.8 per 10 000 live births in 1995 to 3.4 per 10 000 in 2014. Eighty-three patients with Down syndrome died during this period. The overall 6-month and 1- and 5-year survival probabilities were 95.8%, 94.4%, and 91.8%, respectively. There was a significant decrease in mortality rates over the study period, particularly among those born between 2000-2004 and 2005-2009 compared with those born between 1995 and 1999 (P < .05). Patients with Down syndrome without congenital cardiovascular anomalies and without low birth weight had lower mortality rates than those with these diagnoses. Conclusions: Over the past 2 decades, the early life mortality of children with Down syndrome in Hong Kong has improved significantly along with a reduction in Down syndrome live births

Risk of child maltreatment in Chinese teenage and young mothers with rapid repeat pregnancy: the moderating role of family cohesion and support from friends

Rapid repeat pregnancy (RRP) often occurs in teenage and young mothers. Mothers with a history of RRP are more likely to experience high stress increasing their risk of child maltreatment. Despite these challenges, some mothers can continue to cope adaptively. Social support may play a role in empowering these mothers to overcome the childbearing difficulties. Although the protective effects of social support are well recognized, there has been little evidence on the relative importance of sources of support. For example, whether support from family and friends is equally important in relieving parenting stress remains unanswered. RRP, a social phenomenon encompassing various adverse living and parenting issues, provides an ideal research context to investigate the role of family and friends in preventing child maltreatment. This study examined whether family cohesion and friends’ support moderated the association between RRP and child maltreatment in young mothers. We recruited 392 Chinese teenage and young mothers from a population-based integrated young mothers supporting program in Hong Kong. Questionnaires on pregnancy history, family cohesion, social support, and risk of child maltreatment were administered. Moderation analysis was conducted to examine the effect of RRP on child maltreatment as a function of family cohesion or friend support. Results showed that RRP was associated with a higher risk of child neglect (adjusted odds ratio [aOR] = 1.72, p < .05) and physical maltreatment (aOR = 1.91, p < .01), and that family cohesion was more important than friend support in mitigating the risk of child maltreatment for mothers with a history of RRP. Our findings suggest that interventions for young mothers, particularly those with a history of RRP, should be family-based so the whole family can be empowered to tackle the childrearing burden