What childhood obesity prevention programmes work? A systematic review and meta-analysis

The potential of a year-round school calendar for maintaining children's weight status and fitness: Preliminary outcomes from a natural experiment

Purpose

To evaluate the potential of a year-round school calendar (180-day school year distributed across 12 months) as an intervention compared to a traditional school calendar (180-day school year distributed across 9 months) for mitigating children's weight gain and fitness loss via a natural experiment.

Methods

Height, weight, and cardiorespiratory fitness (CRF) (i.e., Fitnessgram Progressive Aerobic Cardiovascular Endurance Run) were measured in children (5-12 years old) in 3 schools (2 traditional, 1 year-round, n = 990 students, age = 8.6 ± 2.4 years, 53.1% male, 68.9% African American) from 1 school district. Structure (represented by the presence of a school day) was the independent variable. Changes in body mass index (BMI), age- and sex-specific BMI z-scores (zBMI), BMI percentile, percent of overweight or obese children, and CRF (Progressive Aerobic Cardiovascular Endurance Run laps completed) were assessed for summer 2017 (May-August 2017), school year 2017/2018 (August 2017-May 2018), and summer 2018 (May-August 2018). Primary analyses examined the overall change in weight and CRF from summer 2017 until summer 2018 via multilevel mixed effects regression, with group (traditional vs. year-round calendar), time, and a group-by-time interaction as the independent variables. Secondary regression analyses estimated differences in change within and between groups during each time period, separately.

Results

Year-round students gained less BMI (difference in ∆ = -0.44, 95% confidence interval (CI): -0.67 to -0.03) and less CRF (difference in ∆ = -1.92, 95%CI: -3.56 to -0.28) than students attending a traditional school overall. Compared with traditional students, during both summers, year-round students gained less BMI (summer 2017 difference in ∆ = -0.15, 95%CI: -0.21 to -0.08; summer 2018 difference in ∆ = -0.16, 95%CI: -0.24 to -0.07) and zBMI (summer 2017 difference in ∆ = -0.032, 95%CI: -0.050 to -0.010; summer 2018 difference in ∆ = -0.033, 95%CI: -0.056 to -0.009), and increased CRF (summer 2017 difference in ∆ = 0.40, 95%CI: 0.02-0.85; summer 2018 difference in ∆ = 0.23, 95%CI: -0.25 to 0.74). However, the opposite was observed for the school year, with traditional students gaining less BMI and zBMI and increasing CRF compared with year-round students (difference in BMI ∆ = 0.05, 95%CI: 0.03-0.07; difference in zBMI ∆ = 0.012, 95%CI: 0.005-0.019; difference in Progressive Aerobic Cardiovascular Endurance Run laps ∆ = -0.43, 95%CI: -0.58 to -0.28).

Conclusion

The year-round school calendar had a small beneficial impact on children's weight status but not CRF. It is unclear if this benefit to children's weight would be maintained because gains made in the summer were largely erased during the school year. Trajectories of weight and CRF gain/loss were consistent with the structured days hypothesis.

Parent preferences for text messages containing infant feeding advice

BACKGROUND

Text-messaging is beneficial in health promotion. Research on impact of message framing (gain- versus loss-framed) has had variable results, depending on type of behavior targeted. There is no research on framing of text-messaging to promote healthful infant feeding practices.

METHODS

The purpose of this cross-sectional survey was to examine whether parents of infants aged three months or younger viewed gain- or loss-framed text messages as more helpful and which style was viewed as more likely to affect feeding practices. A secondary purpose was to determine what time of day and frequency of messaging was preferred. Parents were recruited from an urban pediatric medical clinic. PsychData was used to administer the survey. Parents rated message pairs targeting constructs of the Health Belief Model using a five-point Likert scale. Paired t- tests compared overall ratings for helpfulness and likelihood of messages affecting feeding practices between gain- and loss-framed messages. Descriptive and frequency analyses were applied to demographics and questions regarding preferred timing for receiving messages.

RESULTS

A total of 34 parents (3 fathers and 31 mothers, mean age 26±5.5 years) completed the survey, with 41% enrolled in WIC and 29% in SNAP. There was no overall difference in helpfulness or likelihood of messages affecting feeding practices between gain- and loss-framed messages. Message style did not affect likelihood of adopting a feeding practice. However, gain framed messages relating to benefits and self-efficacy for breastfeeding were viewed more positively (mean =2.32; P=0.034; mean =1.79; P=0.041, respectively). The greatest proportion of parents (38%) preferred receiving messages once per week, and 50% preferred morning messages.

CONCLUSIONS

Framing of text messages appeared to have little effect on parents' acceptance of messages related to infant feeding practices. Parents were receptive to receiving messages from their infant's healthcare provider once per week, in the morning.

Cost-Effectiveness of an Obesity Management Program for 6- to 15-Year-Old Children in Poland: Data from Over Three Thousand Participants

BACKGROUND

Obesity and overweight, including childhood obesity and overweight, pose a public health challenge worldwide. According to the available research findings, long-term interventions focusing on dietary behavior, physical activity, and psychological support are the most effective in reducing obesity in children aged 6-18 years. There are limited studies showing the financial effectiveness of such interventions.

OBJECTIVE

The objective of the present study was to evaluate cost-effectiveness of the 6-10-14 for Health weight management program using pharmacoeconomic indicators, i.e., cost-effectiveness analysis using the incremental cost-effectiveness ratio.

METHODS

We used anthropometric data of 3,081 children included in a 1-year-long intervention with a full financial cost assessment.

RESULTS

The cost of removing a child from the overweight group (BMI >85th percentile) was PLN 27,758 (EUR 6,463), and the cost of removing a child from the obese group (BMI >95th percentile) was slightly lower, i.e., PLN 23,601 (EUR 5,495). Given the obesity-related medical costs calculated in the life-long perspective, these results can be considered encouraging. At the same time, when comparing the total costs per participant with the costs of other interventions, it can be noted that they are similar to the costs of school programs containing more than 1 type of intervention.

CONCLUSIONS

The 6-10-14 for Health program can be considered cost-effective. As a result of committing financial resources in the approximate amount of EUR 1,790 per child, around half of the children participating in the program have improved their weight indicators.

Co-designing obesity prevention interventions together with children: intervention mapping meets youth-led participatory action research

BACKGROUND

Youth-led Participatory Action Research (YPAR) involves children throughout the process of developing and implementing interventions. Combining YPAR with a structural approach for designing and planning interventions, such as Intervention Mapping (IM), may further improve implementation and effectiveness of interventions. This paper describes how YPAR and IM were combined in the Kids in Action study.

METHODS

The Kids in Action study aims to improve health behaviors of 9-12-year old children living in a low socioeconomic neighborhood in Amsterdam, by co-designing interventions with these children. At each of four schools 6-8 children (N = 18-24 total per year) and two academic researchers formed participatory groups that met weekly or every fortnight during two school years. An IM expert panel advised the participatory groups on the application of IM.

RESULTS

Following the IM protocol, we conducted a participatory needs assessment with children, parents and professionals, in IM-step 1. In IM-step 2, the IM expert panel constructed matrices of program objectives, and the children provided feedback. In collaboration with children programs were designed and produced using an iterative process during IM-steps 3-4. In IM-step 5, the participatory groups and professional community partners designed the implementation plan. Finally, in IM-step 6, the protocol of the process and effect evaluation - executed by academic researchers with input from children - was developed.

CONCLUSIONS

By combining YPAR and IM, several interventions have been developed and implemented, varying from a school water policy to extracurricular sports activities. Sharing responsibility with children was challenging when combining IM with YPAR. In YPAR children are given as much autonomy as possible, while traditional IM development work is primarily done by academic researchers. Strengths in combining IM and YPAR include the involvement of the end-users - children - throughout the process while at the same time developing interventions based on existing evidence. Time-management, a multidisciplinary team, and flexibility are important conditions when combining IM with YPAR. A strong community project group, with professionals who were willing to help children develop and execute their ideas, was an important success factor. This study can serve as an example to other YPAR studies developing interventions using the IM protocol.

Race/ethnic variations in school-year versus summer differences in adolescent physical activity

Children and adolescents gain more weight in the summer than the school year, and there are race/ethnic differences in this pattern. Youth physical activity is lower in the summer, and the main aim of the present study was to examine race/ethnic and sex differences in adolescent physical activity, sedentary behavior, and related variables, comparing the school-year and summer. Adolescents aged 11-17 years were recruited from lower-income areas of five states in 2017-2018, and n = 207 completed surveys in both the school-year and summer: 56 African Americans, 30 American Indians, 21 Asian/Pacific Islanders, 49 Latinos, and 51 White, non-Hispanics. Of these, n = 150 also had accelerometer data. Objectively-measured physical activity was lower in the summer, especially among American Indian, Asian/Pacific Islander, and Latino subgroups. Reported screen time was substantially higher in the summer (p < .04), with the biggest increase among African Americans. Reported enjoyment of physical activity was generally lower in the summer (p < .02), which could help explain reduced physical activity. Which race/ethnic groups were at higher risk in the summer varied for physical activity and screen time, so interventions should be tailored for each group. Improved strategies to increase physical activity in the summer, especially among higher-risk groups, could contribute to youth obesity control.

Frequency of school-based intervention needed to improve weight outcomes of Mexican-American adolescents with overweight or obesity: a randomized controlled trial

BACKGROUND

Efficacious school-based interventions among ethnic minority youth are often intensive and difficult to disseminate.

OBJECTIVE

This parallel, open-label-randomized controlled trial aimed to compare changes in adolescent-standardized body mass index (zBMI) from a school-based obesity intervention given 0, 1, 3, or 5 days a week.

METHODS

Mexican-American youth (n = 243) with overweight or obesity were recruited from a Houston school district and randomized to receive an obesity intervention with established efficacy 0 (control), 1, 3, or 5 d/wk (respectively, equating to 0, 40, 120, or 200 min of contact each week). In each condition, 80% of intervention time was allocated to physical activity and 20% to nutrition, with behavioural modification overlaid throughout. zBMI was calculated from directly measured height and weight. A linear mixed model evaluated differences in zBMI over time between conditions.

RESULTS

Participants were 12.02 ± 0.57 years old with a zBMI of 1.80 ± 0.46 at baseline. Among those with complete data at 1 year (n = 203), a significant condition by time interaction was indicated (F = 9.42, P < .001). Those who received the intervention 3 or 5 d/wk had significantly greater decreases in zBMI than control (respectively, -0.19 zBMI units/y; 95% CI, -0.28 to -0.11; and -0.18 zBMI units/y; 95% CI, -0.27 to -0.10, both P < .001). No differences were found between 3 and 5 d/wk (95% CI, -0.09-0.08, P = .87).

CONCLUSIONS

The intervention provided 3 d/wk resulted in similar zBMI improvements as the intervention provided 5 d/wk. This information can be used to develop scalable school-based obesity interventions.

The epidemiological burden of obesity in childhood: a worldwide epidemic requiring urgent action

BACKGROUND

In recent decades, the prevalence of obesity in children has increased dramatically. This worldwide epidemic has important consequences, including psychiatric, psychological and psychosocial disorders in childhood and increased risk of developing non-communicable diseases (NCDs) later in life. Treatment of obesity is difficult and children with excess weight are likely to become adults with obesity. These trends have led member states of the World Health Organization (WHO) to endorse a target of no increase in obesity in childhood by 2025.

MAIN BODY

Estimates of overweight in children aged under 5 years are available jointly from the United Nations Children's Fund (UNICEF), WHO and the World Bank. The Institute for Health Metrics and Evaluation (IHME) has published country-level estimates of obesity in children aged 2-4 years. For children aged 5-19 years, obesity estimates are available from the NCD Risk Factor Collaboration. The global prevalence of overweight in children aged 5 years or under has increased modestly, but with heterogeneous trends in low and middle-income regions, while the prevalence of obesity in children aged 2-4 years has increased moderately. In 1975, obesity in children aged 5-19 years was relatively rare, but was much more common in 2016.

CONCLUSIONS

It is recognised that the key drivers of this epidemic form an obesogenic environment, which includes changing food systems and reduced physical activity. Although cost-effective interventions such as WHO 'best buys' have been identified, political will and implementation have so far been limited. There is therefore a need to implement effective programmes and policies in multiple sectors to address overnutrition, undernutrition, mobility and physical activity. To be successful, the obesity epidemic must be a political priority, with these issues addressed both locally and globally. Work by governments, civil society, private corporations and other key stakeholders must be coordinated.

A School-Based Intervention Using Health Mentors to Address Childhood Obesity by Strengthening School Wellness Policy

PURPOSE AND OBJECTIVES

The objective of our study was to strengthen wellness policy in Title 1 schools by implementing a mentored behavior-change model that extends the continuum of care from academic to community settings and mobilizes existing public resources in accordance with US Preventive Services Task Force screening guidelines for childhood obesity management.

INTERVENTION APPROACH

Team Kid POWER! (KiPOW!) health mentors (students and trainees in medical and health-related fields) in 2 geographically and demographically distinct school districts, the District of Columbia and Orange County, California, delivered standardized health curricular modules to fifth grade classrooms, modeled healthy eating behaviors during school lunchtime, and engaged in active play at recess.

EVALUATION METHODS

Initial interventions in the the District of Columbia and Orange County delivered 10 sessions in which all participants received the intervention. Two subsequent interventions in Orange County, for 5 weeks (Lite) and 10 weeks (Full), included controls. Pre-post measurements of body mass index (BMI) and blood pressure were documented in all participants. A mixed linear regression model, which included a random effect for each school, estimated differences between Full and Lite interventions compared with controls, adjusting for site, sex, and baseline status of the dependent variable.

RESULTS

KiPOW! Full, but not KiPOW! Lite, was associated with a modest reduction in BMI percentile compared with control (KiPOW! Full, P = .04; KiPOW! Lite, P = .41), especially in Orange County (P < .001). Systolic blood pressure improved in Full (P < .046) more than in Lite interventions (P = .11), and diastolic blood pressure improved in both Full (P = .02) and Lite (P = .03) interventions. Annual renewal of the school and volunteer commitment needed to maintain KiPOW! was found to be sustainable.

IMPLICATIONS FOR PUBLIC HEALTH

KiPOW! is a generalizable academic-community partnership promoting face-to-face contact between students and trusted health mentors to reinforce school wellness policies and foster youth confidence in decision-making about nutrition- and activity-related behaviors to achieve reduced BMI percentile and lowered blood pressure.

Impact on Physical Fitness of the Chinese CHAMPS: A Clustered Randomized Controlled Trial

BACKGROUND

School physical activity (PA) policy, physical education curriculum, teacher training, knowledge of physical fitness, and parental support are among the key issues underlying the declining trend of physical fitness in children and adolescents. The Chinese CHAMPS was a multi-faceted intervention program to maximize the opportunities for moderate and vigorous physical activity (MVPA), and increase physical fitness in middle school students. The purpose of the study was to test whether the levels of modification in school physical education policy and curriculum incrementally influenced the changes in cardiorespiratory fitness and other physical fitness outcomes.

METHODS

This 8-month study was a clustered randomized controlled trial using a 2 × 2 factorial design. The participants were 680 7th grade students (mean age = 12.66 years) enrolled in 12 middle schools that were randomly assigned to one of four treatment conditions: school physical education intervention (SPE), afterschool program intervention (ASP), SPE+ASP, and control. Targeted behaviors of the Chinese CHAMPS were the student's sedentary behavior and MVPA. The study outcomes were assessed by a test battery of physical fitness at the baseline and posttest. Sedentary behavior and MVPA were measured in randomly selected students using observations and accelerometry.

RESULTS

The terms contrasting the pooled effect of SPE, ASP, and SPE+ASP vs. Control, the pooled effect of SPE and SPE+ASP vs. ASP only, and the effect of SPE+ASP vs. ASP on CRF and other physical fitness outcomes were all significant after adjusting for covariates, supporting the study hypothesis. Process evaluation demonstrated high fidelity of the intervention in the targeted students' behaviors.

CONCLUSIONS

Chinese CHAMPS demonstrated the impact of varying the amount of MVPA and vigorous physical activity (VPA) on the physical fitness in middle school students in support of the need to increase the opportunity for PA in schools and to introduce high-intensity exercises in school-based PA programs. Modification of school policy, quality of physical education curriculum, and teacher training were important moderators of the improvement in physical fitness. (Trial registration: ChiCTR-IOR-14005388, the Childhood Health; Activity and Motor Performance Study.).

NASA Mission X Program for Healthy Eating and Active Living among Taiwanese Elementary School Students

PURPOSE

This study assessed the effects of an intervention program adapted from the NASA Mission X (MX) program on children's Healthy Eating Active Living (HEAL) knowledge and behaviors and anthropometry.

METHODS

This clustered randomized control trial recruited 8 elementary schools in remote rural areas of Northern Taiwan. The intervention was the 8-week MX program. All the 3rd and 4th graders were invited to the study (n = 245). Children's weight, height, HEAL knowledge and behaviors were measured pre- and post-intervention.

RESULTS

The intervention group had significantly more improvements than control group in physical activity knowledge score (+0.91 vs. +0.25, p = 0.002), diet knowledge score (+0.62 vs. +0.17, p = 0.044), and score of interests in NASA and space exploration (+0.34 vs. -0.07, p < 0.0001). BMI increased from 18.4 to 18.6 (p < 0.05) for the control group but did not change for the intervention group. The changes in BMI between groups did not differ significantly.

CONCLUSION AND PRACTICE IMPLICATIONS

This randomized controlled trial showed that the NASA MX program was feasible and acceptable among children in Taiwan, and improved children's HEAL knowledge. (ClinicalTrials.gov registration: NCT03355131).

The CHIRPY DRAGON intervention in preventing obesity in Chinese primary-school--aged children: A cluster-randomised controlled trial

BACKGROUND

In countries undergoing rapid economic transition such as China, rates of increase in childhood obesity exceed that in the West. However, prevention trials in these countries are inadequate in both quantity and methodological quality. In high-income countries, recent reviews have demonstrated that school-based prevention interventions are moderately effective but have some methodological limitations. To address these issues, this study evaluated clinical- and cost- effectiveness of the Chinese Primary School Children Physical Activity and Dietary Behaviour Changes Intervention (CHIRPY DRAGON) developed using the United Kingdom Medical Research Council complex intervention framework to prevent obesity in Chinese primary-school-aged children.

METHODS AND FINDINGS

In this cluster-randomised controlled trial, we recruited 40 state-funded primary schools from urban districts of Guangzhou, China. A total of 1,641 year-one children with parent/guardian consent took part in baseline assessments prior to stratified randomisation of schools (intervention arm, 20 schools, n = 832, mean age = 6.15 years, 55.6% boys; control arm n = 809, mean age = 6.14 years, 53.3% boys). The 12-month intervention programme included 4 school- and family-based components delivered by 5 dedicated project staff. We promoted physical activity and healthy eating behaviours through educational and practical workshops, family activities, and supporting the school to improve physical activity and food provision. The primary outcome, assessed blind to allocation, was between-arm difference in body mass index (BMI) z score at completion of the intervention. A range of prespecified, secondary anthropometric, behavioural, and psychosocial outcomes were also measured. We estimated cost effectiveness based on quality-adjusted life years (QALYs), taking a public sector perspective. Attrition was low with 55 children lost to follow up (3.4%) and no school dropout. Implementation adherence was high. Using intention to treat analysis, the mean difference (MD) in BMI z scores (intervention - control) was -0.13 (-0.26 to 0.00, p = 0.048), with the effect being greater in girls (MD = -0.18, -0.32 to -0.05, p = 0.007, p for interaction = 0.015) and in children with overweight or obesity at baseline (MD = -0.49, -0.73 to -0.25, p < 0.001, p for interaction < 0.001). Significant beneficial intervention effects were also observed on consumption of fruit and vegetables, sugar-sweetened beverages and unhealthy snacks, screen-based sedentary behaviour, and physical activity in the intervention group. Cost effectiveness was estimated at £1,760 per QALY, with the probability of the intervention being cost effective compared with usual care being at least 95% at a willingness to pay threshold of £20,000 to 30,000 per QALY. There was no evidence of adverse effects or harms. The main limitations of this study were the use of dietary assessment tools not yet validated for Chinese children and the use of the UK value set to estimate QALYS.

CONCLUSIONS

This school- and family-based obesity prevention programme was effective and highly cost effective in reducing BMI z scores in primary-school-aged children in China. Future research should identify strategies to enhance beneficial effects among boys and investigate the transferability of the intervention to other provinces in China and countries that share the same language and cultures.

TRIAL REGISTRATION

ISRCTN Identifier ISRCTN11867516.

Adverse childhood experiences are associated with an increased risk of obesity in early adolescence: a population-based prospective cohort study

OBJECTIVE

To determine whether adverse childhood experiences were associated with weight gain and obesity risk in adolescence.

METHODS

We analyzed data from 6942 adolescents followed between 9 and 13 years of age in the Growing Up in Ireland cohort study. The main exposures were 14 adverse childhood experiences, 4 of which were included in the Adverse Childhood Experience (ACE) study. The primary outcome was incident overweight and obesity at 13 years. Secondary outcomes included prevalent overweight/obesity and weight gain.

RESULTS

More than 75% of the youth experienced an adverse experience and 17% experienced an ACE-specific experience before 9 years. At 13 years, 48% were female and 31.4% were overweight or obese. After adjusting for confounding, exposure to any adverse experience was associated with prevalent overweight/obesity (aOR: 1.56; 1.19-2.05) and incident overweight/obesity (adjusted IRR: 2.15; 95% CI: 1.37-3.39), while exposure to an ACE-specific exposure was associated weight gain (BMI Z score change = 0.202; 95% CI: 0.100-0.303). A significant interaction between income and adverse childhood experiences was observed for both incident overweight/obesity and weight gain (BMI Z change: -0.046; 95% CI: -0.092 to 0.000).

CONCLUSIONS

Adverse childhood experiences and low income interact and independently predict obesity risk in early adolescence.

Accuracy of Body Weight Estimation Among Palestinian Refugee Adolescents Living in Jordan: A Cross-Sectional Study

PURPOSE

We aimed to examine the prevalence of obesity among adolescents living in a refugee camp in Jordan and analyze the factors influencing their weight perceptions.

DESIGN

Cross-sectional survey.

METHODS

We examined the body weight perception, and the influence of psychological, cultural, and social factors, among Palestinian refugee adolescents living in Jordan using a cross-sectional survey. Univariate, bivariate, and multiple logistic regression analyses were used to investigate the relationships between body weight status, weight perception, satisfaction with weight, screen time, and depression status of these adolescents.

RESULTS

A total of 620 adolescents participated in the study, of which 24% were either overweight or obese. Overweight or obese adolescents were more likely to underestimate their weight (p < .001), while those with depressive symptoms (Patient Health Questionnaire for Adolescents score > 14), were more likely to overestimate their body weight (p = .021). Having symptoms indicative of depression (adjusted odds ratio [AOR] = 1.70; 95% confidence interval [CI] = 1.16-2.50) and having a body mass index in the overweight/obese range (AOR = 4.16; 95% CI = 2.73-6.35) were predictors of discordant weight perception.

CONCLUSIONS

This study showed that excess body weight is a significant issue among Palestinian refugee adolescents living in a refugee camp in Jordan. Underlying depression is an important factor in excess weight and distorted weight perceptions especially among this vulnerable group.

CLINICAL RELEVANCE

The study highlights the importance of addressing discordant body weight perception and depression in weight management in nursing interventions for vulnerable adolescent groups.

Efficacy of a compulsory homework programme for increasing physical activity and improving nutrition in children: a cluster randomised controlled trial

Background

Most physical activity interventions in children focus on the school setting; however, children typically engage in more sedentary activities and spend more time eating when at home. The primary aim of this cluster randomised controlled trial was to investigate the effects of a compulsory, health-related homework programme on physical activity, dietary patterns, and body size in primary school-aged children.

Methods

A total of 675 children aged 7–10 years from 16 New Zealand primary schools participated in the Healthy Homework study. Schools were randomised into intervention and control groups (1:1 allocation). Intervention schools implemented an 8-week applied homework and in-class teaching module designed to increase physical activity and improve dietary patterns. Physical activity was the primary outcome measure, and was assessed using two sealed pedometers that monitored school- and home-based activity separately. Secondary outcome measures included screen-based sedentary time and selected dietary patterns assessed via parental proxy questionnaire. In addition, height, weight, and waist circumference were measured to obtain body mass index (BMI) and waist-to-height ratio (WHtR). All measurements were taken at baseline (T₀), immediately post-intervention (T₁), and 6-months post-intervention (T₂). Changes in outcome measures over time were estimated using generalised linear mixed models (GLMMs) that adjusted for fixed (group, age, sex, group x time) and random (subjects nested within schools) effects. Intervention effects were also quantified using GLMMs adjusted for baseline values.

Results

Significant intervention effects were observed for weekday physical activity at home (T₁ [P < 0.001] and T₂ [P = 0.019]), weekend physical activity (T₁ [P < 0.001] and T₂ [P < 0.001]), BMI (T₂ only [P = 0.020]) and fruit consumption (T₁ only [P = 0.036]). Additional analyses revealed that the greatest improvements in physical activity occurred in children from the most socioeconomically deprived schools. No consistent effects on sedentary time, WHtR, or other dietary patterns were observed.

Conclusions

A compulsory health-related homework programme resulted in substantial and consistent increases in children’s physical activity – particularly outside of school and on weekends – with limited effects on body size and fruit consumption. Overall, our findings support the integration of compulsory home-focused strategies for improving health behaviours into primary education curricula.

Trial registration

Australian New Zealand Clinical Trials Registry, ACTRN12618000590268. Registered 17 April 2018.

Electronic supplementary material

The online version of this article (10.1186/s12966-019-0840-3) contains supplementary material, which is available to authorized users.

The Daily Mile as a public health intervention: a rapid ethnographic assessment of uptake and implementation in South London, UK

Background

Existing evidence identifies health benefits for children of additional daily physical activity (PA) on a range of cardiovascular and metabolic outcomes. The Daily Mile (TDM) is a popular scheme designed to increase children’s PA within the school day. Emerging evidence indicates that participation in TDM can increase children’s PA, reduce sedentarism and reduce skinfold measures. However, little is known about the potential effects of TDM as a public health intervention, and the benefits and disbenefits that might flow from wider implementation in ‘real world’ settings.

Methods

We aimed to identify how TDM is being implemented in a naturalistic setting, and what implications this has for its potential impact on population health. We undertook a rapid ethnographic assessment of uptake and implementation in Lewisham, south London. Data included interviews (n = 22) and focus groups (n = 11) with stakeholders; observations of implementation in 12 classes; and analysis of routine data sources to identify school level factors associated with uptake.

Results

Of the 69 primary schools in one borough, 33 (48%) had adopted TDM by September 2018. There were no significant differences between adopters and non-adopters in mean school population size (means 377 vs 397, P = 0.70), mean percentage of children eligible for free school meals (16.2 vs 14.3%, P = 0.39), or mean percentage of children from Black and Minority Ethnic populations (76.3 vs 78.2%, P = 0.41). Addressing obesity was a key incentive for adoption, although a range of health and educational benefits were also hypothesised to accrue from participation. Mapping TDM to the TIDierR-PHP checklist to describe the intervention in practice identified that considerable adaption happened at the level of borough, school, class and pupil. Population health effects are likely to be influenced by the interaction of intervention and context at each of these levels.

Conclusions

Examining TDM in ‘real world’ settings surfaces adaptions and variations in implementation. This has implications for the likely effects of TDM, and points more broadly to an urgent need for more appropriate methods for evaluating public health impact and implementation in complex contexts.

Electronic supplementary material

The online version of this article (10.1186/s12889-019-7511-9) contains supplementary material, which is available to authorized users.

Kids SIPsmartER, a cluster randomized controlled trial and multi-level intervention to improve sugar-sweetened beverages behaviors among Appalachian middle-school students: Rationale, design & methods

The intake of sugar-sweetened beverages (SSB) is disproportionately high in Appalachia, including among adolescents whose intake is more than double the national average and more than four times the recommended daily amount. Unfortunately, there is insufficient evidence for effective strategies targeting SSB behaviors among Appalachian youth in real-world settings, including rural schools. Kids SIPsmartER is a 6-month, school-based, behavior and health literacy program aimed at improving SSB behaviors among middle school students. The program also integrates a two-way short message service (SMS) strategy to engage caregivers in SSB role modeling and supporting home SSB environment changes. Kids SIPsmartER is grounded by the Theory of Planned Behavior and health literacy, media literacy, numeracy, and public health literacy concepts. Guided by the RE-AIM framework (reach, effectiveness, adoption, implementation, and maintenance), this type 1 hybrid design and cluster randomized controlled trial targets 12 Appalachian middle schools in southwest Virginia. The primary aim evaluates changes in SSB behaviors at 7-months among 7th grade students at schools receiving Kids SIPsmartER, as compared to control schools. Secondary outcomes include other changes in students (e.g., BMI, quality of life, theory-related variables) and caregivers (e.g., SSB behaviors, home SSB environment), and 19-month maintenance of these outcomes. Reach is assessed, along with mixed-methods strategies (e.g., interviews, surveys, observation) to determine how teachers implement Kids SIPsmartER and the potential for institutionalization within schools. This paper discusses the rationale for implementing and evaluating a type 1 hybrid design and multi-level intervention addressing pervasive SSB behaviors in Appalachia. Clincialtrials.gov: NCT03740113.

Prevention and treatment of childhood and adolescent obesity: a systematic review of meta-analyses

BACKGROUND

The goal of this systematic review is to synthesize the published meta-analyses assessing the role of nutritional, behavioral and physical activity factors/interventions on the prevention or treatment of pediatric and adolescent obesity.

METHODS

An online search was conducted in PubMed (end-of-search: September 30, 2015); English-language meta-analyses pooling observational and/or interventional studies examining weight-related indices on children and adolescents were included.

RESULTS

Sixty-six meta-analyses corresponding to more than 900,000 children and adolescents were retrieved. The majority of meta-analyses included interventional studies most of which referred to mixed or combined interventions, including components such as diet, physical activity and sedentary behavior reduction. Discrepancies between meta-analyses on observational and interventional studies were noted. Combined interventions including physical activity and nutritional modifications seemed to represent the most effective means for tackling childhood obesity.

CONCLUSIONS

Synthesis of interventional or observational evidence may yield discrepant results. The combination of enhanced physical activity and improved nutrition emerged as a promising intervention in the fight against childhood/adolescent obesity. However, further research is needed about the most effective multidimensional prevention strategy.

Physical activity interventions in early life aimed at reducing later risk of obesity and related non-communicable diseases: A rapid review of systematic reviews

To identify useful components of interventions aimed at prevention of childhood obesity and related non-communicable diseases (NCDs), which included physical activity and which targeted any or all of four life-course stages: peri-conception; pregnancy; infancy and toddlerhood (0 to 23 months); and early childhood (24 to 59 months). In May 2016, WHO Geneva searched the Cochrane Library and PubMed for systematic reviews of interventions including physical activity to prevent childhood obesity or risk factors for obesity-related NCDs. Using a narrative synthesis, the efficacy of randomized controlled trials (RCTs) to alter energy balance outcomes (measures of weight status or body fatness) was characterized by life-course stage, study characteristics, intervention functions (as defined in the behaviour change wheel), and level of the socio-ecological model (SEM) targeted. The quality of included systematic reviews was assessed. We retrieved 82 reviews from the World Health Organization (WHO) search, of which 23 were eligible for the present synthesis. The number of eligible studies by life-course stage was: 0 (peri-conception); 0 (pregnancy); 8 (infancy and toddlerhood, age 0 to 23 months; seven RCTs; age); and 37 (early childhood, age 24 to 59 months; 30 RCTs;). Thus, there was a lack of evidence for physical activity interventions during peri-conception and pregnancy. Almost all relevant studies in the 0- to 23- and 24- to 59-month life-course stages were multicomponent interventions (ie, targeted physical activity, dietary, and/or sedentary behaviours). Interventions with evidence of efficacy tended to target multiple levels of the SEM, with emphasis on parents, and extend over long periods. Effective intervention elements for early life obesity prevention included classes on parenting skills, alteration of the kindergarten playground, and financial incentives. Evidence from low- and middle-income countries was scarce, and evidence for intervention effect on obesity-related NCDs was missing. Future physical activity interventions in toddlerhood and early childhood aimed at prevention of obesity should adopt the characteristics typical of effective interventions identified by the present synthesis. There is an urgent need for more evidence on physical activity interventions set in low- and middle-income countries and which target the peri-conception and pregnancy periods.

Evidence-based Nutritional Intervention Protocol for Korean Moderate-Severe Obese Children and Adolescents

Diet-related behavioral modification for healthy eating and lifestyle is required to improve childhood obesity. The present study aimed to develop customized nutritional intervention protocol and education program to find barriers to adhere healthy diet and lifestyle for moderate to severe obese children and adolescents and their families. Theoretical framework approaches can be used to change behavior and achieve goals. Previous studies that described the relationship between behavioral modification and nutrition education theory were reviewed. The social cognitive theory and transtheoretical model were employed with behavioral changes to target a healthful diet and lifestyle. The nutrition care process (NCP) model was adopted to customize nutrition care for the participants. Customized nutritional intervention protocol was developed following as the four steps of the NCP. Firstly, nutrition status of the participants was assessed by the nutrition expert. Nutrition problems were described as "inadequate energy intake," "overweight/obesity," or "food and nutrition-related knowledge deficit." All nutrition sessions were designed for nutrition intervention to give nutritional knowledge and a practical mission in real life for individual goal setting and self-control. Meal planning, portion control, healthy snack selection and cooking with fruits and vegetables were consisted of five components of the nutrition education session. During each session, the participants and their families were interviewed by a nutrition expert for monitoring and evaluating diet-related goal setting and achievement. A theoretical and evidence-based nutritional intervention was developed for the secondary to tertiary prevention of childhood obesity. This nutrition intervention protocol and program might be helpful for the further research on childhood obesity.

Trial Registration

Clinical Research Information Service Identifier: KCT0002111.

Effectiveness of Teacher-Led Nutritional Lessons in Altering Dietary Habits and Nutritional Status in Preschool Children: Adoption of a NASA Mission X-Based Program

The preschool years are a sensitive period for the development of food preferences that will affect physical growth and life-long health. The promotion of healthy eating and nutritional status was achieved by adapting the US National Aeronautics and Space Administration (NASA) Mission X (MX) Program among young children in South Korea. The intervention program was delivered by nutritional experts and class teachers over 10 weeks. Children from 37 school classes (n = 534) from 7 daycares and kindergartens were randomized into a control group (CG, n = 280) and an intervention group (IG, n = 254). Parents were surveyed for their children’s characteristics and nutrition quotient (NQ) at baseline and at the 10-week follow-up. At baseline, 18.8% (boys: 18.9%; girls: 18.8%) of the subjects were overweight or obese (body mass index ≥ 85th percentile). After the intervention, the mean differences in various anthropometric measures did not differ significantly between the groups in a linear regression model adjusted for age, sex, and type of school. The NQ grades were significantly higher in the IG than the CG after the intervention (p = 0.000). In summary, the 10-week South Korean MX program improved the eating behaviors and nutrition status of young children. A further multisector prevention program is needed to prevent childhood obesity in young children.

A cluster randomised trial of an intervention to increase the implementation of physical activity practices in secondary schools: study protocol for scaling up the Physical Activity 4 Everyone (PA4E1) program

Background

The implementation of interventions at-scale is required to maximise population health benefits. ‘Physical Activity 4 Everyone (PA4E1)’ was a multi-component school-based program targeting adolescents attending secondary schools in low socio-economic areas. An efficacy trial of the intervention demonstrated an increase in students’ mean minutes of moderate-to-vigorous physical activity (MVPA) per day and lower weight gain at low incremental cost. This study aims to assess the effectiveness and cost effectiveness of a multi-component implementation support intervention to improve implementation, at-scale, of the evidence based school physical activity (PA) practices of the PA4E1 program. Impact on student PA levels and adiposity will also be assessed, in addition to the cost of implementation.

Methods

A cluster randomised controlled trial, utilising an effectiveness-implementation hybrid design, will be conducted in up to 76 secondary schools located in lower socio-economic areas across four health districts in New South Wales (NSW), Australia. Schools will be randomly allocated to a usual practice control arm or a multi-component implementation support intervention to embed the seven school PA practices of the PA4E1 program. The implementation support intervention incorporates seven strategies including executive support, in-School Champion, teacher training, resources, prompts, audit and feedback and access to an external Support Officer. The primary trial outcome will be the proportion of schools meeting at least four of the seven physical activity practices of the program, assessed via surveys with Head Physical Education teachers at 12 and 24-months. Secondary outcomes will be assessed via a nested evaluation of student PA and adiposity at 12-months (Grade 8 students) and 24 months (Grade 9 students) undertaken in 30 schools (15 per group). Resource use associated with the implementation intervention will be measured prospectively. Linear mixed effects regression models will assess program effects on the primary outcome at each follow-up period.

Discussion

This study is one of few evidence-based multi-component PA programs scaled-up to a large number of secondary schools and evaluated via randomised controlled trial. The use of implementation science theoretical frameworks to implement the evidence-based program and the rigorous evaluation design are strengths of the study.

Trial registration

Australian New Zealand Clinical Trials Registry ACTRN12617000681358 registered 12th May 2017. Protocol Version 1.

Electronic supplementary material

The online version of this article (10.1186/s12889-019-6965-0) contains supplementary material, which is available to authorized users.

Scaling-up evidence-based obesity interventions: A systematic review assessing intervention adaptations and effectiveness and quantifying the scale-up penalty

Maximizing the benefits of investments in obesity research requires effective interventions to be adopted and disseminated broadly across populations (scaled-up). However, interventions often need considerable adaptation to enable implementation at scale, a process that can reduce the effects of interventions. A systematic review was undertaken for trials that sought to deliver an obesity intervention to populations on a larger scale than a preceding randomized controlled trial (RCT) that established its efficacy. Ten scaled-up obesity interventions (six prevention and four treatment) were included. All trials made adaptations to interventions as part of the scale-up process, with mode of delivery adaptations being most common. A meta-analysis of body mass index (BMI)/BMI z score (zBMI) from three prevention RCTs found no significant benefit of scaled-up interventions relative to control (standardized mean difference [SMD] = 0.03; 95% CI, -0.09 to 0.15, P = 0.639 - I²  = 0.0%). All four treatment interventions reported significant improvement on all measures of weight status. Pooled BMI/zBMI data from prevention trials found significantly lower effects among scaled-up intervention trials than those reported in pre-scale-up efficacy trials (SMD = -0.11; 95% CI, -0.20 to -0.02, P = 0.018 - I²  = 0.0%). Across measures of weight status, physical activity/sedentary behaviour, and nutrition, the effects reported in scaled-up interventions were typically 75% or less of the effects reported in pre-scale-up efficacy trials. The findings underscore the challenge of scaling-up obesity interventions.

Association of neighborhood built environments with childhood obesity: Evidence from a 9-year longitudinal, nationally representative survey in the US

BACKGROUND

The built environment is an important contributor to childhood obesity; however, large-scale and longitudinal studies designed to examine their associations remain limited. This study aimed to examine whether walkable neighborhoods were associated with childhood obesity risk over a 9-year period.

METHODS

We used data collected in the US nationally representative Early Childhood Longitudinal Study - Kindergarten (ECLS-K) Cohort, with 9440 kindergarteners followed up until their 8th grade (1998-2007). Four built environmental variables, street intersection density, residential density, fitness facility density, and recreational facility density, were calculated from national census, business, and road network datasets, and then matched with ECLS-K samples. Mixed-effect models were performed to estimate associations between built environments and child weight status.

RESULTS

Children who experienced increased intersection density during 1998-2007 had a lower BMI in 2007 (β = -0.49, p < 0.01), especially girls (β = -0.79, p < 0.01) and suburban children (β = -0.66, p < 0.05). They also had lower obesity risk in 2007 (OR = 0.79 [95% CI = 0.66-0.94]), especially girls (OR = 0.68 [95% CI = 0.52-0.88]). Girls and boys who lived in neighborhoods with the higher (but not highest) residential density in 1998 showed lower obesity risk (OR = 0.54 [95% CI = 0.30-0.98]) and overweight risk (OR = 0.54 [95% CI = 0.30-0.95]) in 2007, respectively.

CONCLUSIONS

National data indicate that in the US greater walkability in residential neighborhoods may lead to lower child BMI and obesity risk after nine years, and the association was stronger among girls and in suburban regions. This provides useful evidence for future obesity prevention and urban planning.

Project Spraoi: a two-year longitudinal study on the effectiveness of a school-based nutrition and physical activity intervention on dietary intake, nutritional knowledge and markers of health of Irish schoolchildren

OBJECTIVE

To assess the effectiveness of a nutrition and physical activity (PA) intervention on dietary intake (DI), nutritional knowledge (NK), blood pressure (BP), anthropometric measures and cardiorespiratory fitness (CRF) of schoolchildren.

DESIGN

Longitudinal study. DI, NK, BMI, waist-to-height ratio (WHtR), BP and CRF were all measured/calculated prior to (October 2014) and at the end of (June 2016) intervention delivery.

SETTING

Two primary schools (one intervention and one control), Cork, Ireland.

PARTICIPANTS

Six-year-olds (n 49; mean age = 6·09 (sd 0·33) years) and 10-year-olds (n 52; mean age = 9·90 (sd 0·37) years).

RESULTS

There was a large and a moderate statistically significant difference between the change in systolic (P = 0·005, effect size (ES) = 0·165) and diastolic BP (P = 0·023, ES = 0·116), respectively, for 10-year-olds in the intervention and control groups. There was also a large statistically significant difference between the change in WHtR (P = 0·0005, ES = 0·386) and a moderate statistically significant difference between the change in NK (P = 0·027, ES = 0·107) for 10-year-olds in the intervention and control groups. There was a large statistically significant difference between the change in percentage of energy from protein in 10-year-old females (P = 0·021, ES = 0·276) in the intervention and control groups.

CONCLUSIONS

Project Spraoi is Ireland's first ever school-based intervention that has been evaluated and proven effective in improving DI, NK, WHtR and BP in older primary-school children in one intervention school.

Two Family Interventions to Reduce BMI in Low-Income Urban Youth: A Randomized Trial

BACKGROUND

Our primary aim was to evaluate the effects of 2 family-based obesity management interventions compared with a control group on BMI in low-income adolescents with overweight or obesity.

METHODS

In this randomized clinical trial, 360 urban-residing youth and a parent were randomly assigned to 1 of 2 behaviorally distinct family interventions or an education-only control group. Eligible children were entering the sixth grade with a BMI ≥85th percentile. Interventions were 3 years in length; data were collected annually for 3 years. Effects of the interventions on BMI slope (primary outcome) over 3 years and a set of secondary outcomes were assessed.

RESULTS

Participants were primarily African American (77%), had a family income of <25 000 per year, and obese at enrollment (68%). BMI increased over time in all study groups, with group increases ranging from 0.95 to 1.08. In an intent-to-treat analysis, no significant differences were found in adjusted BMI slopes between either of the family-based interventions and the control group (P = .35). No differences were found between the experimental and control groups on secondary outcomes of diet, physical activity, sleep, perceived stress, or cardiometabolic factors. No evidence of effect modification of the study arms by sex, race and/or ethnicity, household income, baseline levels of child and parent obesity, or exposure to a school fitness program were found.

CONCLUSIONS

In this low-income, adolescent population, neither of the family-based interventions improved BMI or health-related secondary outcomes. Future interventions should more fully address poverty and other social issues contributing to childhood obesity.

The association between maternal body mass index and child obesity: A systematic review and meta-analysis

BACKGROUND

There is a global obesity crisis, particularly among women and disadvantaged populations. Early-life intervention to prevent childhood obesity is a priority for public health, global health, and clinical practice. Understanding the association between childhood obesity and maternal pre-pregnancy weight status would inform policy and practice by allowing one to estimate the potential for offspring health gain through channelling resources into intervention. This systematic review and meta-analysis aimed to examine the dose-response association between maternal body mass index (BMI) and childhood obesity in the offspring.

METHODS AND FINDINGS

Searches in MEDLINE, Child Development & Adolescent Studies, CINAHL, Embase, and PsycInfo were carried out in August 2017 and updated in March 2019. Supplementary searches included hand-searching reference lists, performing citation searching, and contacting authors. Two researchers carried out independent screening, data extraction, and quality assessment. Observational studies published in English and reporting associations between continuous and/or categorical maternal and child BMI or z-score were included. Categorical outcomes were child obesity (≥95th percentile, primary outcome), overweight/obesity (≥85th percentile), and overweight (85th to 95th percentile). Linear and nonlinear dose-response meta-analyses were conducted using random effects models. Studies that could not be included in meta-analyses were summarised narratively. Seventy-nine of 41,301 studies identified met the inclusion criteria (n = 59 cohorts). Meta-analyses of child obesity included 20 studies (n = 88,872); child overweight/obesity, 22 studies (n = 181,800); and overweight, 10 studies (n = 53,238). Associations were nonlinear and there were significantly increased odds of child obesity with maternal obesity (odds ratio [OR] 3.64, 95% CI 2.68-4.95) and maternal overweight (OR 1.89, 95% CI 1.62-2.19). Significantly increased odds were observed for child overweight/obesity (OR 2.69, 95% CI 2.10-3.46) and for child overweight (OR 1.80, 95% CI 1.25, 2.59) with maternal obesity. A limitation of this research is that the included studies did not always report the data in a format that enabled inclusion in this complex meta-analysis.

CONCLUSIONS

This research has identified a 264% increase in the odds of child obesity when mothers have obesity before conception. This study provides substantial evidence for the need to develop interventions that commence prior to conception, to support women of childbearing age with weight management in order to halt intergenerational obesity.

Feasibility of enhancing well-child visits with family nutrition and physical activity risk assessment on body mass index

OBJECTIVE

Integration of behavioural risk assessment into well-child visits is recommended by clinical guidelines, but its feasibility and impact is unknown.

METHODS

A quasi-experimental study evaluated the feasibility and effectiveness of risk assessment on body mass index (BMI) at 1-year follow-up. Children with assessments (intervention) were compared with those who did not complete assessments (non-respondent) and those who received standard care (non-exposed).

RESULTS

Analyses included 10,647 children aged 2-9 years (2,724 intervention, 3,324 non-respondent and 4,599 non-exposed). Forty-five per cent of parents completed the assessments. Intervention and non-respondent groups differed in change in BMI z-score at 1 year by -0.05 (confidence interval [CI]: -0.08, -0.02; P = 0.0013); no difference was observed with non-exposed children. The intervention group had a smaller increase in BMI z-score (0.07 ± 0.63) than non-respondent group (0.13 ± 0.63). For children with normal weight at baseline, intervention versus non-respondent groups differed in BMI z-score change by -0.06 (CI: -0.10, -0.02; P = 0.0025). However, children with overweight at baseline in the intervention versus the non-exposed group differed in BMI z-score change (0.07 [CI: 0.02, 0.14]; P = 0.016). When analysed by age, results were similar for 2- to 5-year-olds, but no differences were found for 6- to 9-year-olds.

CONCLUSION

Automating risk assessment in paediatric care is feasible and effective in promoting healthy weight among preschool but not older children.

Evaluation of the Computer-Based Intervention Program Stayingfit Brazil to Promote Healthy Eating Habits: The Results from a School Cluster-Randomized Controlled Trial

Interventions via the Internet are promising regarding the promotion of healthy habits among youth. The objective of this study was to evaluate the effect of an adapted version of StayingFit to promote healthy eating habits and the measurement adequacy of anthropometric markers among adolescents. A web school-based 12-month cluster-randomized controlled trial examining 7th to 9th grade students was conducted in twelve schools in Salvador, Bahia, Brazil. The schools' students were randomly distributed into the intervention and control groups. The intervention group participated in StayingFit, an online program designed to encourage and guide healthy eating habits and control body weight. Data on food consumption, anthropometry, physical activity level, and sedentary behavior were collected from all of the students at the beginning of and after the 12-month study. Demographic and socioeconomic data were collected at baseline. The baseline data indicated high rates of overweight (14.4% overweight and 8.5% obese), insufficiently active (87.6%), and sedentary (63.7%). Furthermore, few adolescents regularly consumed fruits (18.8%) and vegetables/legumes (16.4%). Generalized estimating equations (GEEs) were used to evaluate the effect of the intervention. At the end of the follow-up period, students in the intervention group had a 43% increased chance of regularly consuming beans (OR = 1.43, 95% CIs = 1.10-1.86) and a 35% decreased chance of regularly consuming soft drinks (OR = 0.65, 95% CIs = 0.50-0.84). No differences were found between the groups studied with regard to the anthropometric parameters. Despite these modest results, the implementation of a web intervention can be beneficial and help promote positive changes in adolescent eating habits.

The West Midlands ActiVe lifestyle and healthy Eating in School children (WAVES) study: a cluster randomised controlled trial testing the clinical effectiveness and cost-effectiveness of a multifaceted obesity prevention intervention programme targeted at children aged 6-7 years

BACKGROUND

Systematic reviews suggest that school-based interventions can be effective in preventing childhood obesity, but better-designed trials are needed that consider costs, process, equity, potential harms and longer-term outcomes.

OBJECTIVE

To assess the clinical effectiveness and cost-effectiveness of the WAVES (West Midlands ActiVe lifestyle and healthy Eating in School children) study intervention, compared with usual practice, in preventing obesity among primary school children.

DESIGN

A cluster randomised controlled trial, split across two groups, which were randomised using a blocked balancing algorithm. Schools/participants could not be blinded to trial arm. Measurement staff were blind to allocation arm as far as possible.

SETTING

Primary schools, West Midlands, UK.

PARTICIPANTS

Schools within a 35-mile radius of the study centre and all year 1 pupils (aged 5-6 years) were eligible. Schools with a higher proportion of pupils from minority ethnic populations were oversampled to enable subgroup analyses.

INTERVENTIONS

The 12-month intervention encouraged healthy eating/physical activity (PA) by (1) helping teachers to provide 30 minutes of additional daily PA, (2) promoting 'Villa Vitality' (interactive healthy lifestyles learning, in an inspirational setting), (3) running school-based healthy cooking skills/education workshops for parents and children and (4) highlighting information to families with regard to local PA opportunities.

MAIN OUTCOME MEASURES

The primary outcomes were the difference in body mass index z-scores (BMI-zs) between arms (adjusted for baseline body mass index) at 3 and 18 months post intervention (clinical outcome), and cost per quality-adjusted life-year (QALY) (cost-effectiveness outcome). The secondary outcomes were further anthropometric, dietary, PA and psychological measurements, and the difference in BMI-z between arms at 27 months post intervention in a subset of schools.

RESULTS

Two groups of schools were randomised: 27 in 2011 (n = 650 pupils) [group 1 (G1)] and another 27 in 2012 (n = 817 pupils) [group 2 (G2)]. Primary outcome data were available at first follow-up (n = 1249 pupils) and second follow-up (n = 1145 pupils) from 53 schools. The mean difference (MD) in BMI-z between the control and intervention arms was -0.075 [95% confidence interval (CI) -0.183 to 0.033] and -0.027 (95% CI -0.137 to 0.083) at 3 and 18 months post intervention, respectively. The main analyses showed no evidence of between-arm differences for any secondary outcomes. Third follow-up included data on 467 pupils from 27 G1 schools, and showed a statistically significant difference in BMI-z (MD -0.20, 95% CI -0.40 to -0.01). The mean cost of the intervention was £266.35 per consented child (£155.53 per child receiving the intervention). The incremental cost-effectiveness ratio associated with the base case was £46,083 per QALY (best case £26,804 per QALY), suggesting that the intervention was not cost-effective.

LIMITATIONS

The presence of baseline primary outcome imbalance between the arms, and interschool variation in fidelity of intervention delivery.

CONCLUSIONS

The primary analyses show no evidence of clinical effectiveness or cost-effectiveness of the WAVES study intervention. A post hoc analysis, driven by findings at third follow-up, suggests a possible intervention effect, which could have been attenuated by baseline imbalances. There was no evidence of an intervention effect on measures of diet or PA and no evidence of harm.

FUTURE WORK

A realist evidence synthesis could provide insights into contextual factors and strategies for future interventions. School-based interventions need to be integrated within a wider societal framework and supported by upstream interventions.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN97000586.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 22, No. 8. See the NIHR Journals Library website for further project information.

Childhood Obesity Prevention in Africa: A Systematic Review of Intervention Effectiveness and Implementation

Childhood obesity is of increasing concern in many parts of Africa. We conducted a systematic search and review of published literature on behavioural childhood obesity prevention interventions. A literature search identified peer-reviewed literature from seven databases, and unindexed African journals, including experimental studies targeting children age 2–18 years in African countries, published in any language since 1990. All experimental designs were eligible; outcomes of interest were both behavioural (physical activity, dietary behaviours) and anthropometric (weight, body mass index, body composition). We also searched for process evaluations or other implementation observations. Methodological quality was assessed; evidence was synthesised narratively as a meta-analysis was not possible. Seventeen articles describing 14 interventions in three countries (South Africa, Tunisia and Uganda) were included. Effect scores indicated no overall effect on dietary behaviours, with some beneficial effects on physical activity and anthropometric outcomes. The quality of evidence was predominantly weak. We identified barriers and facilitators to successful interventions, and these were largely resource-related. Our systematic review highlights research gaps in targeting alternative settings to schools, and younger age groups, and a need for more rigorous designs for evaluating effectiveness. We also recommend process evaluations being used more widely.

Food, Health, & Choices: Curriculum and Wellness Interventions to Decrease Childhood Obesity in Fifth-Graders

OBJECTIVE

To evaluate Food, Health, & Choices, two 10-month interventions.

DESIGN

Cluster-randomized, controlled study with 4 groups: curriculum, wellness, curriculum plus wellness, and control.

SETTING

Twenty elementary schools (5/group) in New York City.

PARTICIPANTS

Fifth-grade students (n = 1,159). At baseline, 44.6% were at the ≥85th body mass index (BMI) percentile for age and 86% qualified for free or reduced-price lunch.

INTERVENTION

Curriculum was 23 science lessons based on social cognitive and self-determination theories, replacing 2 mandated units. Wellness was classroom food policy and physical activity bouts of Dance Breaks.

MAIN OUTCOME MEASURES

For obesity, age- and sex-specific BMI percentiles were used (anthropometric measures). The researchers also employed 6 energy balance-related behaviors and 8 theory-based determinants of behavior change (by questionnaire).

ANALYSIS

Pairwise adjusted odds in hierarchical logistic regression models were determined for >85th BMI percentile. Behaviors and theory-based determinants were examined in a 2-level hierarchical linear model with a 2 × 2 design for intervention effects and interactions.

RESULTS

Obesity showed no change. For behaviors, there was a negative curriculum intervention change in physical activity (P = .04). The wellness intervention resulted in positive changes for sweetened beverages frequency (P = .05) and size (P = .006); processed packaged snacks size (P = .01); candy frequency (P = .04); baked good frequency (P = .05); and fast food frequency (P = .003), size (P = .01), and combo meals (P = .002). Theory-based determinants demonstrated no change.

CONCLUSIONS AND IMPLICATIONS

The findings of the lack of a decrease in obesity, behavior changes only for the wellness intervention, and no changes in theory-based determinants warrant further research.

Kids in Action: the protocol of a Youth Participatory Action Research project to promote physical activity and dietary behaviour

INTRODUCTION

In this study, researchers collaborate with children from a low socioeconomic neighbourhood in Amsterdam in developing, implementing and evaluating interventions targeting their health behaviours. This Youth Participatory Action Research project focuses on the promotion of physical activity and healthy dietary behaviour.

METHODS AND ANALYSIS

This study is a controlled trial using participatory methods to develop interventions together with children aged 9-12 years. At four primary schools in a low socioeconomic neighbourhood in Amsterdam, an 'Action Team' is installed: a group of six to eight children who actively participate as co-researchers in developing, implementing and evaluating interventions. An academic researcher facilitates the participatory process. Four control schools, also located in low socioeconomic areas in and around Amsterdam, continue with their regular curriculum and do not participate in the participatory process. For the effect evaluation, physical activity and sedentary behaviour are assessed using accelerometers and self-reporting; dietary behaviour using self-reporting and motor fitness (strength, flexibility, coordination, speed and endurance) using the motor performance fitness test. Effectiveness of the interventions is evaluated by multilevel regression analysis. The process of co-creating interventions and the implemented interventions is continually evaluated during meetings of the Action Teams and with children participating in the interventions. Empowerment of children is evaluated during focus groups. Summaries and transcripts of meetings are coded and analysed to enrich children's findings.

ETHICS AND DISSEMINATION

The Medical Ethics Committee of the VU Medical Center approved the study protocol (2016.366).

TRIAL REGISTRATION NUMBER

TC=6604.

Grappling With Complex Food Systems to Reduce Obesity: A US Public Health Challenge

Despite 2 decades of effort by the public health community to combat obesity, obesity rates in the United States continue to rise. This lack of progress raises fundamental questions about the adequacy of our current approaches. Although the causes of population-wide obesity are multifactorial, attention to food systems as potential drivers of obesity has been prominent. However, the relationships between broader food systems and obesity are not always well understood. Our efforts to address obesity can be advanced and improved by the use of systems approaches that consider outcomes of the interconnected global food system, including undernutrition, climate change, the environmental sustainability of agriculture, and other social and economic concerns. By implementing innovative local and state programs, taking new approaches to overcome political obstacles to effect policy, and reconceptualizing research needs, we can improve obesity prevention efforts that target the food systems, maximize positive outcomes, and minimize adverse consequences. We recommend strengthening innovative local policies and programs, particularly those that involve community members in identifying problems and potential solutions and that embrace a broad set of goals beyond making eating patterns healthier. We also recommend undertaking interdisciplinary research projects that go beyond testing targeted interventions in specific populations and aim to build an understanding of the broader social, political, and economic context.

Prevention of Childhood Obesity in Child Health Services: Follow-Up of the PRIMROSE Trial

BACKGROUND

Childhood obesity is an urgent public health concern, and there's a need for long-term, high-quality, primary prevention trials targeting parents of young children. The aim of the current study was to evaluate the long-term effect of a parental support program based on motivational interviewing (MI).

METHODS

A cluster randomized controlled trial was carried out in eight Swedish counties. Participating families (N = 1355) were enrolled when the child was 9 months old, and participated in nine sessions during ∼39 months. The aim was to pomote healthy food and physical activity (PA) habits using MI and principles from cognitive behavioral therapy. Nurses in Swedish child health services delivered the intervention, and the control group received usual healthcare. The current study was a 1-year follow-up of effects on children's weight-related measures. Regression analyses were conducted using generalized estimating equations, including analyses to investigate potential parental moderators of the effect.

RESULTS

There were no statistically significant intervention effects at follow-up [BMI difference = -0.13, p = 0.29, overweight relative risk (RR) = 0.96, p = 0.78, obesity RR = 0.57, p = 0.20]. Maternal waist circumference and unhealthy eating and paternal PA moderated the effect, but effects were small and failed to reach statistical significance after correction for multiple comparisons.

CONCLUSIONS

A parent-focused primary prevention intervention based on MI delivered within child health services did not result in effects at 1-year follow-up. The results were in line with those obtained at post-assessment and indicated no late onset of effect. Further studies exploring individual and contextual factors influencing the outcome are called for.

Context Considerations for Developing the In Defense of Food Nutrition Education Curriculum

OBJECTIVE

To examine perceptions of teachers and afterschool program staff related to the positive aspects and challenges of afterschool education for youth to guide the development of the "In Defense of Food" nutrition education curriculum.

METHODS

Semi-structured in-depth interviews with a convenience sample of teachers and afterschool program staff experienced serving at-risk youth were conducted in New York, NY. They were audio-recorded, transcribed verbatim, and analyzed using inductive summative content analysis to identify, count, and compare themes.

RESULTS

Interviews (n = 12) generated 2 meta-themes (Pedagogical Elements for Successful Learning and Pragmatic Considerations for hosting health promotion programs in the afterschool context). Learner-centered and tailored approaches and building social connection were considered important for fostering learning in the afterschool context.

CONCLUSIONS AND IMPLICATIONS

This study emphasizes the importance of considering pedagogical elements related to delivery that minimizes didactic instruction and focuses on learner-centered approaches. Further research is needed to compare outcomes and process measures common approaches used in designing nutrition education curricula with those that have been described in this study.

Ripple Effect Mapping Outcomes of a Childhood Obesity Prevention Program From Youth and Adult Dyads Using a Qualitative Approach: iCook 4-H

OBJECTIVE

To describe the impact of the iCook 4-H intervention study based on data gathered through ripple effect mapping focus groups through an explorative approach.

DESIGN

Youth-adult dyads responded about ways in which iCook had affected the individual, family, and community. Three questions were asked: (1) What were people doing differently as a result of iCook? (2) Who benefited from iCook and how? (3) Were there changes in the way community groups and institutions did things as a result of iCook?

SETTING

Ripple effect mapping sessions took place across 5 states (Maine, Nebraska, South Dakota, Tennessee, and West Virginia).

PARTICIPANTS

Seventy dyad participants (n = 35 youth, n = 35 adults) from the iCook 4-H intervention.

MAIN OUTCOME MEASURE

Three core themes of iCook 4-H were assessed: cooking, eating, and playing together.

ANALYSIS

Direct content analysis and word frequencies were used.

RESULTS

Seven categories emerged: improved health, increased community involvement, increased knowledge, increased communication, changed motivation, financial mindfulness, and increased appreciation for family. An overarching theme that was determined was that learning new skills together through trying new things (cooking, eating, and playing) leads to positive individual family and community change.

CONCLUSIONS AND IMPLICATIONS

Ripple effect mapping was effective in determining the perceived impact of iCook 4-H on oneself, family, and community.

Longitudinal Associations between Emotion Regulation and Adiposity in Late Adolescence: Indirect Effects through Eating Behaviors

The prevalence of obesity among U.S. youth continues to increase, with many adolescents engaging in unhealthy eating behaviors. Increasingly, research points to the role of self-regulation in obesity development, yet existing work has largely focused on young children and/or clinical adult populations. This multi-method longitudinal study (N = 153) utilized a path analysis to delineate links between emotion regulation (age 15), emotional eating and dietary restraint (age 16), and adiposity (% body fat) using a BodPod for body composition assessment (age 19). Emotion regulation was negatively associated with emotional eating (β = -0.30, p < 0.001) and positively associated with dietary restraint (β = 0.15, p < 0.05) at age 16, but was not associated with age 19 adiposity (β = -0.01, p = ns). Emotional eating was positively associated with adiposity (β = 0.24, p < 0.01). Indirect effects suggested that emotional eating, but not dietary restraint, at age 16 serves as a mechanism that helps explain the associations between emotion regulation and adiposity four years later. Results from this study suggest that both emotion regulation and emotional eating represent promising targets for that should be included in future interventions aimed at preventing adolescent obesity.

A Systematic Review of Methods, Study Quality, and Results of Economic Evaluation for Childhood and Adolescent Obesity Intervention

Many suggested policy interventions for childhood and adolescent obesity have costs and effects that fall outside the health care sector. These cross-sectorial costs and consequences have implications for how economic evaluation is applied and although previous systematic reviews have provided a summary of cost-effectiveness, very few have conducted a review of methods applied. We undertook this comprehensive review of economic evaluations, appraising the methods used, assessing the quality of the economic evaluations, and summarising cost-effectiveness. Nine electronic databases were searched for full-economic evaluation studies published between January 2001 and April 2017 with no language or country restrictions. 39 economic evaluation studies were reviewed and quality assessed. Almost all the studies were from Western countries and methods were found to vary by country, setting and type of intervention. The majority, particularly "behavioural and policy" preventive interventions, were cost-effective, even cost-saving. Only four interventions were not cost effective. This systematic review suggests that economic evaluation of obesity interventions is an expanding area of research. However, methodological heterogeneity makes evidence synthesis challenging. Whilst upstream interventions show promise, an expanded and consistent approach to evaluate cost-effectiveness is needed to capture health and non-health costs and consequences.

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.

Effectiveness of a school-based physical activity intervention on adiposity, fitness and blood pressure: MOVI-KIDS study

OBJECTIVE

To test a physical activity intervention (MOVI-KIDS) on obesity indicators, physical fitness and blood pressure (BP) in children.

METHODS

A crossover randomised cluster trial was conducted, which comprised 1434 children (4-7 years old) from 21 schools in the provinces of Cuenca and Ciudad Real in the Castilla-La Mancha region of Spain. The intervention consisted of three 60 min sessions/week on weekdays between October 2013 and May 2014. Changes in anthropometric variables, physical fitness and BP parameters were measured. The analyses used were mixed regression models to adjust for baseline covariates under cluster randomisation.

RESULTS

There was no significant improvement in overweight/obesity with the intervention compared with the control group in both sexes. Further, the intervention did not alter other adiposity indicators or BP parameters. Improvements in cardiorespiratory fitness were seen in girls (1.19; 95% CI 0.31 to 2.08; p=0.008), but not in boys. Finally, there was an improvement in velocity/agility in both girls (-2.51 s; 95% CI -3.98 to -1.05; p=0.001) and boys (-2.35 s; 95% CI -3.71 to -0.98; p=0.001), and in muscular strength in both girls (0.66; 95% CI 0.03 to 1.28; p=0.038) and boys (1.26; 95% CI 0.03 to 1.28; p<0.001).

CONCLUSION

MOVI-KIDS was not successful in reducing the adiposity and maintained BP levels at previous healthy values in children. The intervention, however, showed significant improvements in cardiorespiratory fitness in girls, and muscular strength and velocity/agility in boys and girls.

TRIAL REGISTRATION NUMBER

NCT01971840; Post-results.

Trends and Prevalence of Overweight and Obesity among Children Aged 2-7 Years from 2011 to 2017 in Xiamen, China

BACKGROUND

Childhood overweight and obesity have become some of the most serious public health problems in the 21st century and have a significant impact on affected children as they grow into adulthood.

OBJECTIVE

The purpose of this study was to evaluate the overweight and obesity status and their main influencing factors in preschool children aged 2-7 years in urban areas of China between 2011 and 2017.

METHODS

A stratified cluster random sampling method was used to conduct a sample survey of children aged 2-7 years in Xiamen, one of China's five special economic zones. The 56,738 participants (29,444 boys, 27,294 girls) were examined at three time points (15,757 in 2011, 19,098 in 2014, and 21,883 in 2017), and were analyzed for factors influencing obesity.

RESULTS

Between 2011 and 2017, the prevalence of overweight and obesity in preschool children between 2 and 7 years old was 10.91 and 5.66%, respectively. The overweight and obesity rates were higher in boys (11.85 and 7.11%) than in girls (9.90 and 4.09%), and the difference was statistically significant (p < 0.01). In the past 7 years, the overweight and obesity rates showed a downward trend in both boys and girls (p < 0.01). The peak ages for overweight were 6 years in boys and 2 years in girls, while the obesity rate peaked at 6 years. In those children with obesity, the proportion of those with moderate to severe obesity decreased from 40.70% in 2011 to 32.80% in 2017. Multiple stepwise regression analysis showed that children who were averse to sports activities preferred greasy foods and had earlier introduction of solid foods as infants, as well as those who were born at a high birth weight, ate fast, and those with parents with obesity were more likely to have obesity themselves (p < 0.05).

CONCLUSIONS

Although preventative and control measures for childhood obesity have achieved initial results, Chinese preschool children remain to have high levels of overweight and obesity. It is therefore necessary to strengthen monitoring of overweight and obesity in preschool-aged children and implement appropriate interventions when necessary.

Prevalence and Types of School-Based Out-of-School Time Programs at Elementary Schools and Implications for Student Nutrition and Physical Activity

BACKGROUND

Out-of-school time (OST) programs are an important setting for supporting student health and academic achievement. This study describes the prevalence and characteristics of school-based OST programs, which can inform efforts to promote healthy behaviors in this setting.

METHODS

A nationally representative sample of public elementary schools (N = 640) completed surveys in 2013-2014. Administrators reported on OST programs and policies at their school. Multivariable logistic regression models estimated the prevalence of school-based OST programs, adjusting for school characteristics. Among schools with OST programs (N = 475), chi-square tests identified school characteristics associated with having an OST policy about physical activity or nutrition.

RESULTS

Three fourths of elementary schools (75.6%) had a full- or partial-year school-based OST program, with 30.8% having both. Full- and partial-year programs were significantly less prevalent in rural and township areas versus urban settings. Only 27.5% of schools with OST programs reported having physical activity and/or nutrition policies.

CONCLUSIONS

Most US elementary schools have an on-site OST program, but disparities in access exist, and most lack policies or awareness of existing policies regarding physical activity and nutrition. To maximize OST programs' potential benefits, strategies are needed to increase access to programs and physical activity and/or nutrition policy adoption.

Teachers' Perceived and Desired Roles in Nutrition Education

BACKGROUND

Elementary teachers have the potential to influence children's eating habits. This study examined teacher views and practices regarding nutrition education.

METHODS

An online survey was administered to K-6 teachers (N = 628) in 55 public elementary schools in a large city in the western United States. Three indices were created based on responses. Indices included: (1) attitudes and beliefs about nutrition education; (2) self-efficacy regarding nutrition education; and (3) personal health behaviors. Relationships between indices, classroom practices, and teacher characteristics were tested. Teacher comments were categorized into themes.

RESULTS

Most teachers agreed they can make a difference in the eating behaviors of their students (68%). Correlations between hours of nutrition taught and teachers' attitudes and beliefs (r = .37, p < .01), nutrition self-efficacy (r = .38, p < .01), and personal health practices (r = .15, p < .01) were weak, yet statistically significant. Number of years teaching was inversely related to frequency of food rewards (r = -119, p < .01). Few teachers (21%) agreed they have support to teach nutrition in the classroom.

CONCLUSION

Teachers understand the importance of nutrition education but provision is limited by competing demands. Teachers suggest tailored nutrition materials, qualified nutrition personnel, and school stakeholder support to promote nutrition education.

'Ripple' effect on infant zBMI trajectory of an internet-based weight loss program for low-income postpartum women

BACKGROUND

Weight loss interventions can have positive 'ripple' effects on untreated partners in the home, but ripple effects on infants are unknown.

OBJECTIVE

To examine whether a 12-month internet-based weight loss intervention for postpartum mothers had a positive ripple effect on participants' infants.

METHODS

A 12-month cluster randomized, assessor-blind, clinical trial enrolling 371 postpartum women at 12 Women, Infants, Children clinics in CA. Clinics were randomized to standard Women, Infants, Children or an internet-based weight loss intervention for mothers.

RESULTS

A total of 333 of the 371 (89.8%) mothers assented for infant participation. Infants were 5.3 ± 3.2 months; 75.9% were Hispanic and 64% were breastfeeding. Infant retention was 272/333 (82.7%) at 6 months post enrollment and 251/333 (75.3%) at 12 months post enrollment. In intent-to-treat analysis, a significant interaction between group and time was observed (p = 0.008) with the offspring of intervention mothers exhibiting lower zBMI change from study entry through 6 months (0.23 [CI, 0.03, 0.44] vs. 0.65 [0.50, 0.79] zBMI change, respectively; p = 0.001) but was not significant through 12 months (p = 0.16). Regardless of group, maternal reports at the final assessment indicated that infants (aged =17.2 ± 3.4 months) consumed sweetened beverages (0.93 ± 1.5/week), juice (2.0 ± 1.4/day), 'junk food' (7.8 ± 5.4/week) and fast food (2/month), and 46.7% of the infants had a TV in their bedroom.

CONCLUSIONS

An internet-based weight loss program for low-income, postpartum mothers had a positive 'ripple' effect on the zBMI of infants in the home during the first 6 months of treatment.

"Prevention Produce": Integrating Medical Student Mentorship into a Fruit and Vegetable Prescription Program for At-Risk Patients

INTRODUCTION

Fruit and vegetable prescription (FVRx) programs provide increased access to produce to food-insecure, at-risk populations, yet many lack the educational and social components to support long-term disease prevention.

OBJECTIVES

To address these barriers, students at Penn State College of Medicine designed "Prevention Produce"-a modified FVRx program that integrated a community-based, month-long educational curriculum-and undertook preliminary evaluation.

METHODS

Nine families deemed by clinicians as at risk of chronic disease and food insecurity received weekly $40 "prescriptions" for produce at partnering farmers markets. Participants were paired with medical student mentors who delivered weekly nutrition education modules and assisted in produce shopping. Preprogram and postprogram surveys were administered, categorizing perceptions and practices of healthy eating. All participants were interviewed by phone 3 years later to assess long-term impact. Medical students provided written reflections via online survey.

RESULTS

Postprogram fruit and vegetable consumption increased, and more patients expressed efforts to include produce in every meal. More participants strongly agreed that fruits and vegetables prevented chronic diseases. In reflective interviews, participants praised the program's ease of use, mentor-patient relationship, and increased access to produce. Student mentors expressed gratitude for one-on-one interaction and felt empowered to learn and deliver nutrition education.

CONCLUSION

Integration of an FVRx program with education, mentorship, and community-based focus may increase produce consumption and improve opinions about healthy eating. This program serves as a model for integrating preventive strategies within larger health care systems. Additionally, the model can facilitate early clinical interventions that may benefit medical trainees' professional development.

Systematic Review of Natural Experiments for Childhood Obesity Prevention and Control

CONTEXT

The National Academy of Medicine recommends childhood obesity prevention efforts making healthier options the passive choice. This review evaluated the effectiveness of population-level policies and programs from natural experiments for childhood obesity prevention.

EVIDENCE ACQUISTION

The search included PubMed, CINAHL, PsycINFO, and EconLit from 2000 to 2017 for policies evaluated by natural experiments reporting childhood BMI outcomes. The studies were analyzed in 2017-2018. Interventions were classified by environmental focus (food/beverage, physical activity, or both) and stratified by setting (school, community, both). Risk of bias was evaluated for each study.

EVIDENCE SYNTHESIS

Of 33 natural experiments, most (73%) took place in the school setting only. The most common environmental focus in any setting was food/beverage (48%). All four studies that focused on both food/beverage and physical activity in schools demonstrated decreased prevalence of overweight/obesity or BMI z-score by 0.04-0.17. BMI decreased in all four studies in both school and community settings. The largest effect size was a decrease in BMI z-score of 0.5, but most were <0.25. The risk of bias was high for most (76%) studies. Most (63%) of the eight studies with low/medium risk of bias took place in the school setting focused on the food/beverage environment; effects on BMI were mixed.

CONCLUSIONS

Natural experiments evaluating school-based policies focusing on both the food/beverage and physical activity environments (versus targeting only one) consistently showed improvement in BMI. However, most studies had high risk of bias, highlighting the need for improved methods for evaluation of natural experiments for childhood obesity prevention.