The Role of Ethnicity in School-Based Obesity Intervention for School-Aged Children: A Pilot Evaluation

Methodological approaches to the design and analysis of nonrandomized intervention studies for the prevention of child and adolescent obesity

OBJECTIVES

Interventions for child obesity prevention are needed and it is unclear whether evidence from nonrandomized intervention studies is adequate. The objective of this research was to review the methods for the design, analysis and reporting of nonrandomized intervention studies for child obesity prevention and to assess potential for bias.

METHODS

We conducted a review of nonrandomized intervention studies, including population health interventions, quasi-experimental studies and natural experiments, published from 2013 to 2017 that were identified in a recent systematic review. Data on study design, intervention and control groups, outcome measures, and statistical analyses, were extracted. Risk of bias was evaluated using the Risk of Bias in Non-Randomized Studies of Interventions (ROBINS-I) tool.

RESULTS

All identified studies (n = 23) included a school or community-based intervention and had a concurrent control group. Participants were 3-18 years and sample sizes were 100 to > 1 million. Study designs were described inconsistently, and interventions ranged from 14 weeks to 5 years. Obesity was compared between control and intervention groups using logistic or linear regression, analysis of variance and mixed effects regression. Only 48% of studies accounted for clustering, and methods to control for confounding and repeated measures varied substantially. Overall risk of bias was moderate to serious for all studies.

CONCLUSION

There are substantial opportunities to improve the methods for nonrandomized intervention studies and reduce bias. Future studies should use advanced statistical and causal epidemiology methods, including better control for confounding and clustering, to generate higher quality evidence and certainty regarding which obesity prevention interventions are effective.

Demographics and anthropometrics impact benefits of health intervention: data from the Reduce Obesity and Diabetes Project

OBJECTIVE

To determine the efficacy of a 4-month school-based health, nutrition and exercise intervention on body fatness and examine possible effects of demographic and anthropometric covariates.

METHODS

Height, weight, waist circumference and body composition were measured in a diverse population of 644 NYC middle school students (mean ± SD age 12.7 ± 0.9 years; 46% male; 38% Hispanic, 17% East Asian, 15% South Asian, 13.5% African American, 8.5% Caucasian, 8% other) during the fall and spring semesters. Year 1 participants (n = 322) were controls. Experimental participants (year 2, n = 469) received a 12-session classroom-based health and nutrition educational programme with an optional exercise intervention.

RESULTS

Groups were demographically and anthropometrically similar. The intervention resulted in significant reductions in indices of adiposity (ΔBMI z-scores [-0.035 ± 0.014; p = 0.01], Δ% body fat [-0.5 ± 0.2; p < 0.0001] and Δwaist circumference [-0.73 ± 0.30 cm; p < 0.0001]). Intervention effects were greater (p = 0.01) in men (ΔBMI z-score = -0.052 ± 0.015) versus women (0.022 ± 0.018), participants who were obese (ΔBMI z-score -0.083 ± 0.022 kg m-2) versus lean (-0.0097 ± 0.020 kg m-2) and South Asians (Δ% body fat -1.03 ± 0.35) versus total (-0.49 ± 0.20%) participants (p = 0.005).

CONCLUSION

A 4-month school-based health intervention was effective in decreasing measures of adiposity in middle school students, particularly in men, participants who were obese and South Asians.

Interventions to prevent global childhood overweight and obesity: a systematic review

In view of the prevalence, health consequences, and costs of childhood obesity, there has been substantial interest in identifying effective interventions to prevent excess weight gain in young people. In this systematic review, we expand on previous reviews of obesity prevention interventions by including recent studies (until May 23, 2017) from all parts of the world. We searched MEDLINE, Embase, CINAHL Plus, Web of Science, CAB Abstracts, and PAIS Index and included randomised controlled trials, quasi-experimental studies, or natural experiments with: (1) a control group; (2) minimum follow-up of 12 months for community-based and home-based interventions or 6 months for school-based and preschool-based interventions; and (3) a primary outcome of BMI, BMI Z score, BMI percentile, body fat percentage, skinfold thickness, waist circumference, or prevalence of overweight or obesity. School-based interventions with combined diet and physical activity components and a home element (n=41) had greatest effectiveness; evidence in support of the effect of preschool-based (n=6), community-based (n=7), and home-based (n=2) interventions was limited by a paucity of studies and heterogeneity in study design. The effectiveness of school-based interventions that combined diet and physical activity components suggests that they hold promise for childhood obesity prevention worldwide. More research with rigorous evaluation and consistent reporting is needed in non-school settings and in combinations of settings.

Health Literacy in School

Health literacy is a core element of patient-centered healthcare. Poor health literacy is a silent epidemic across the globe as it affects every aspect of health. Schools bear an important role in increasing health literacy. Improving health literacy in adolescence is supposed to improve the later life as adolescents are used to carry their modified behavior lifelong. Various school-based interventions covering physical and mental health have been studied and found to be effective. International bodies recommend incorporation of health-related tasks into school lessons and considered that teaching the young people will be a good investment for future. Multisectoral collaborations and locally proved effective strategies are the practical challenges. This chapter aims to focus on health literacy, global scenario of health literacy, measurement tools, role of school, interventions, limitations, and challenges of health literacy.