Effect of intervention programs in schools to reduce screen time: a meta-analysis

Interventions to Promote Physical Activity and Healthy Digital Media Use in Children and Adolescents: A Systematic Review

OBJECTIVES

To identify effective interventions that promote healthy screen time use and reduce sedentary behavior in school-age children and adolescents (SACA) in all settings, over the last 20 years.

METHODS

Searches were conducted from 2000 until March 2021 using PubMed, Embase, Medline, PsycINFO, Ovid SP, The Cochrane Library, Cochrane Central Register of Controlled Trials, Cochrane Methodology Register, and the WHO regional databases, including Google Scholar and reference lists of relevant articles and reviews. Randomized-controlled trials and quasi-experimental studies assessing interventions to reduce sedentary behaviors and screen time in healthy SACA (aged 5-19.9 years) globally. Data were extracted by 2 reviewers and where possible, pooled with a random-effects model.

RESULTS

The review included 51 studies, of which 23 were included in meta-analyses with 16 418 children and adolescents. Nondigital randomized-controlled trials reported a small, but significant reduction of TV-specific screen time (minutes per day) (mean difference, -12.46; 95% confidence interval, -20.82 to -4.10; moderate quality of evidence) and sedentary behavior (minutes per day) (mean difference, -3.86; 95% confidence interval, -6.30 to -1.41; participants = 8920; studies = 8; P = .002; moderate quality of evidence) as compared with control groups. For quasi-experimental studies, nondigital interventions may make little or no difference on screen time (minutes per day) or sedentary behavior (minutes per day), given the high uncertainty of evidence. Most studies were conducted in a high-income country. Generalizability of results to low- and middle- income countries remain limited.

CONCLUSIONS

Public health policies and programs will be necessary to reduce excessive sedentary behavior and screen time, especially in the post-coronavirus disease 2019 reality.

Effect of screen time intervention on obesity among children and adolescent: A meta-analysis of randomized controlled studies

Several studies have investigated the effect of screen time interventions on obesity in children and adolescents, but the existing results were controversial. This study aimed to analyze the effect of screen time intervention on obesity in children and adolescents. PubMed, Cochrane, Web of Science, Embase databases were searched through December 2020 to identify publications meeting a priori inclusion criteria and references in the published articles were also reviewed. Finally, 14 randomized controlled trials and 1894 subjects were included in this meta-analysis. The results showed that interventions targeting screen time are effective in reducing total screen time (MD: -6.90 h/week, 95% CI: [-9.19 to -4.60], p < 0.001) and television time (MD: -6.17 h/week, 95% CI: [-10.70 to -1.65], p < 0.001) in children and adolescents. However, there was no significant difference between the intervention and control groups in body mass index and body mass index-z score. In conclusion, there is no evidence that screen time interventions alone can decrease obesity risk in children and adolescents, though they can effectively reduce screen time.

Time spent in different sedentary activity domains across adolescence: a follow-up study

OBJECTIVE

This longitudinal study aimed to verify possible changes in the time spent in sedentary activities occurring as screen-time, educational, cultural, social, and transportation domains in a sample of Brazilian adolescents between 2015 and 2017.

METHODS

It is a longitudinal prospective study with 586 adolescents from 12 to 15 years old at the Baseline (2015) enrolled in 14 public schools from Curitiba, Brazil. The Adolescent Sedentary Activity Questionnaire assessed the time spent in sedentary activities in five domains (recreational screen-time, educational, cultural, social, and transportation). A series of linear random effects regressions analyzed changes in the sedentary time between 2015 and 2017, with p < .05.

RESULTS

Overall, 323 adolescents dropped out of the study resulting in a retention rate of 44.9%. The overall sedentary time remained stable from 2015 to 2017 (-3.98 min/day, 95%CI: -15.39; 7.42). The screen-time decreased (-22.22 min/day, 95%CI: -30.30; -14.15), and educational (8.29 min/day, 95% CI: 3.52; 13.06), cultural (3.41 min/day, 95% CI: 0.66; 6.15) and social sedentary activities (8.20 min/day, 95% CI: 2.06; 14.34) increased from 2015 to 2017.

CONCLUSION

Significant reductions in screen-time were evidenced along with increases in time spent on other sedentary activities of educational, cultural, and social nature. KeywordsSedentary behavior, Adolescent health, Longitudinal studies.

Effectiveness of a school-based intervention on physical activity and screen time among adolescents

OBJECTIVES

To evaluate the effectiveness of a multi-component school-based intervention on physical activity (PA) and screen time (ST) among urban adolescents in Bangladesh.

DESIGN

Cluster-randomised controlled trial.

METHODS

Eight high schools were randomly assigned to either intervention group (IG) or control group (CG). Participants (n = 160 per group, 40 school) were in grades 8-9. A 12-week multi-component intervention was developed based on the WHO's Health-Promoting Schools framework. The IG received weekly supervised circuit exercise (30 min/week), health education session (10 min/week) with health educational materials, and lunchtime sports activities (20 min/week). The main outcome measures included self-reported PA, ST, knowledge on PA and SB, which were assessed at baseline, 8 and 12 weeks. Repeated measures ANCOVA was used to evaluate the intervention effects.

RESULTS

Total PA (MET-min/week) was increased from baseline to 8 and 12 weeks in the IG (3%-5%) but decreased in the CG (5%-3%) and significantly improved in the IG compared to the CG (p < 0.001) over time. Average ST (min/day) reduced from baseline to 8 and 12 weeks in the IG (28%-35%), while remained unchanged in the CG (6%-5%). The IG had a significantly lower average ST than the CG at 12 weeks. The average knowledge scores on PA and SB were significantly higher in the IG than the CG at 12 weeks (p < 0.001).

CONCLUSIONS

Our intervention has demonstrated some promising effects on increasing PA, reducing ST, and improving PA and SB knowledge. This study underscores the need for a scaled-up evaluation in other locations including rural settings.

Evaluating the effectiveness of interventions to reducing screen time in children: meta-analysis of randomized controlled trials

Purpose

The purpose of this paper is to evaluate the impact of interventions focused on reducing screen time in children.

Design/methodology/approach

Studies that aim to investigate the effects of interventions aimed at reducing the time spent in front of the screen (i.e. screen time). A Random-effects model was used to calculate the pooled standard mean differences. The outcome was to evaluate the screen time in children in the 0–18 age range. A subgroup analysis was performed to reveal the extent to which the overall effect size varied by subgroups (participant age, duration of intervention and follow).

Findings

For the outcome, the meta-analysis included 21 studies, and the standard difference in mean change in screen time in the intervention group compared with the control group was −0.16 (95% confidence interval [CI], −0.21 to −0.12) (p < 0.001). The effect size was found to be higher in long-term (=7 months) interventions and follow-ups (p < 0.05).

Originality/value

Subgroup analysis showed that a significant effect of screen time reduction was observed in studies in which the duration of intervention and follow-up was =7 months. As the evidence base grows, future researchers can contribute to these findings by conducting a more comprehensive analysis of effect modifiers and optimizing interventions to reduce screen time.

Identifying effective intervention strategies to reduce children's screen time: a systematic review and meta-analysis

BACKGROUND

Excessive screen time ([Formula: see text] 2 h per day) is associated with childhood overweight and obesity, physical inactivity, increased sedentary time, unfavorable dietary behaviors, and disrupted sleep. Previous reviews suggest intervening on screen time is associated with reductions in screen time and improvements in other obesogenic behaviors. However, it is unclear what study characteristics and behavior change techniques are potential mechanisms underlying the effectiveness of behavioral interventions. The purpose of this meta-analysis was to identify the behavior change techniques and study characteristics associated with effectiveness in behavioral interventions to reduce children's (0-18 years) screen time.

METHODS

A literature search of four databases (Ebscohost, Web of Science, EMBASE, and PubMed) was executed between January and February 2020 and updated during July 2021. Behavioral interventions targeting reductions in children's (0-18 years) screen time were included. Information on study characteristics (e.g., sample size, duration) and behavior change techniques (e.g., information, goal-setting) were extracted. Data on randomization, allocation concealment, and blinding was extracted and used to assess risk of bias. Meta-regressions were used to explore whether intervention effectiveness was associated with the presence of behavior change techniques and study characteristics.

RESULTS

The search identified 15,529 articles, of which 10,714 were screened for relevancy and 680 were retained for full-text screening. Of these, 204 studies provided quantitative data in the meta-analysis. The overall summary of random effects showed a small, beneficial impact of screen time interventions compared to controls (SDM = 0.116, 95CI 0.08 to 0.15). Inclusion of the Goals, Feedback, and Planning behavioral techniques were associated with a positive impact on intervention effectiveness (SDM = 0.145, 95CI 0.11 to 0.18). Interventions with smaller sample sizes (n < 95) delivered over short durations (< 52 weeks) were associated with larger effects compared to studies with larger sample sizes delivered over longer durations. In the presence of the Goals, Feedback, and Planning behavioral techniques, intervention effectiveness diminished as sample size increased.

CONCLUSIONS

Both intervention content and context are important to consider when designing interventions to reduce children's screen time. As interventions are scaled, determining the active ingredients to optimize interventions along the translational continuum will be crucial to maximize reductions in children's screen time.

What behavior change techniques are associated with effective interventions to reduce screen time in 0-5 year olds? A narrative systematic review

Screen time has been linked to obesity in young children. Therefore, this systematic review aims to investigate which Behavior Change Techniques (BCTs) are associated with the effectiveness of interventions to reduce screen time in 0-5 year olds. Seven databases were searched, including PsycInfo, PubMed, and Medline. Grey literature searches were conducted. Inclusion criteria were interventions reporting pre- and post- outcomes with the primary objective of reducing screen time in 0-5 year olds. Studies were quality assessed using the Effective Public Health Practice Project criteria. Data extracted included participant characteristics, intervention characteristics and screen time outcomes. The BCT Taxonomy was used to extract BCTs. Interventions were categorised as "very", "quite" or "non" promising based on effect sizes. BCTs were deemed promising if they were in twice as many very/quite promising interventions as non-promising interventions. Seven randomised controlled trials were included, involving 642 participants between 2.5 and 5.0 years old. One very promising, four quite promising, and two non-promising interventions were identified. Screen time decreased by 25-39 min per day in very/quite promising interventions. Eleven BCTs were deemed promising, including "behavior substitution" and "information about social and environmental consequences". This review identified eleven promising BCTs, which should be incorporated into future screen time interventions with young children. However, most included studies were of weak quality and limited by the populations targeted. Therefore, future methodologically rigorous interventions targeting at-risk populations with higher screen time, such as those of a low socioeconomic status and children with a high BMI, should be prioritized.

A latent class analysis of psychological symptoms and health risk behaviors among Chinese adolescents

Multiple health risk behaviors (HRBs) tend to co-occur which increase risks of mental disorder. In this study, we identified the association between latent class of HRBs and psychological symptoms in Chinese adolescents. We assessed 22 628 Chinese adolescents from November 2015 to January 2016. The average age of the students were (15.36 ± 1.79), among which there were 10 990 male students and 11 638 female students. A latent class analysis was applied to identity HRBs patterns. The multivariable logistic regression models were utilized to examine the association between HRBs patterns and psychological symptoms. Four latent classes were identified, characterized as low-risk class, moderate-risk class 1 (smoking/ alcohol use (AU)/screen time (ST)), moderate-risk class 2 (unhealthy losing weight (ULW)/ problematic mobile phone use (PMPU)), and high-risk class (ULW/smoking/AU/ST/ PMPU), which were 71.2 %, 3.2 %, 22.3 %, and 3.3 % of involved participants, respectively. Compared to the low-risk class, moderate-risk class 1, moderate-risk class 2, and high-risk class showed that adjusted OR (95 %CI) value of 1.97 (1.68-2.32), 3.98 (3.72-4.26) and 6.38 (CI: 5.47-7.44) were significantly associated with psychological symptoms (P < 0.001 for each). Our findings indicated that identifying different latent class of HRBs would be helpful for the design of tailored interventions, and prevention of different patterns of HRBs should be considered in the implementation of effective intervention programs related to psychological symptoms.

The Relationships between Screen Use and Health Indicators among Infants, Toddlers, and Preschoolers: A Meta-Analysis and Systematic Review

Evidence suggests that excessive screen time in early childhood is related to children's physical and mental health. This study aimed to review the relationships between screen media use and several health indicators in infants, toddlers, and preschoolers. A systematic search was conducted by two independent reviewers on PubMed, Web of Science, Embase, and Cochrane Library to identify the eligible studies, with an end date of 13 August 2019. Included studies (published in English) were peer-reviewed and met the determinate population (children aged 0-7 years with screen media exposure and related health outcomes). The AHRQ, NOS, and the Cochrane Handbook were used to evaluate the cross-sectional study, cohort study, and RCT, respectively. A meta-analysis and narrative syntheses were employed separately. Eighty studies (23 studies for meta-analysis) met the inclusion criteria for the systematic review. Strong evidence of the meta-analysis suggested that excessive screen time was associated with overweight/obesity and shorter sleep duration among toddlers and preschoolers. Excessive screen use was associated with various health indicators in physical, behavioral, and psychosocial aspects. Better-quality research on newer media devices, on various kinds of contents in young children, and on dose-response relationships between excessive screen use and health indicators are needed to update recommendations of screen use.

The effect of computer game playing habits of university students on their sleep states

OBJECTIVE

The aim of this study is to evaluate the effect of computer game playing habits of university students on their sleep states.

DESIGN AND METHODS

The study was conducted cross-sectionally with the online survey method.

FINDING

In this study, it was determined that the students who played games for an average of ≥2 hours per day had later bedtime and later wake-up time, poorer sleep quality, and higher daytime sleepiness. It was found that as the level of game addiction increased, sleep quality decreased, the severity of daytime sleepiness increased, and the wake-up time shifted to a later time.

PRACTICE IMPLICATIONS

Nurses should develop effective intervention strategies involving technology management and sleep hygiene studies to reduce game-playing time of students.

Impact of intervention on nutritional status, consumption of processed foods, and quality of life of adolescents with excess weight

OBJECTIVE

To evaluate the impact of a nutritional intervention on nutritional status, ultra-processed food consumption, and quality of life of adolescents with excess weight.

METHODS

Experimental study with adolescent students with excess weight, divided into two groups, an intervention group and a control group. The nutritional intervention lasted six months, with an educational and motivational approach. Nutritional status (waist circumference and body mass index), quality of life, and ultra-processed food consumption were evaluated before and after the period.

RESULTS

Sixty-two adolescents with overweight or obesity participated in the study, 37 in the intervention group and 25 in the control group, aged 13.2±1.5 years in intervention group, and 13.0±1.8 years in control group, both of which had a higher female participation. There were changes in the body mass index (intervention group Δ: -0.81±2.28, control group Δ: -0.64±1.28) and in the waist circumference for intervention group (Δ:-3.31±5.47). For the pre- and post-ultra-processed food consumption, there was a significant reduction in the consumption of soft drinks in the intervention group (Δ: -0.07 [-0.27 to 0.00]), instant noodles (Δ: -0.03 [-0.07 to 0.00]), and sandwich cookies (Δ: -0.06 [-0.26 to 0.00]). The quality of life increased in the intervention group and decreased in the control group, with no intra- (p=0.162) or intergroup statistical relevance in the pre- (p=0.426) and post- (0.249) intervention period, with a reduction in the emotional domain score, with a significant variation in the intervention group (pre and post; Δ: -19.0±40.6).

CONCLUSION

There was a decrease in body mass index and waist circumference (central obesity being more often related to insulin resistance), reduction of ultra-processed food consumption (soft drinks, sandwich cookies, and instant noodles), and a tendency toward quality of life improvement (however, there was a decrease in the domains of emotional and school quality of life).

Protocol paper for the Movimente school-based program: A cluster-randomized controlled trial targeting physical activity and sedentary behavior among Brazilian adolescents

BACKGROUND

A better understanding of how multicomponent school-based interventions work and their effects on health and education outcomes are needed. This paper described the methods of the Movimente Program, a school-based intervention that aims to increase physical activity (PA) and decrease sedentary behavior (SB) among Brazilian students.

METHODS

This is a cluster randomized controlled trial with adolescents from 7th to 9th grade in public schools from Florianopolis, Southern Brazil. After agreement, 6 schools were randomly selected to intervention or control groups (3 schools each), and all eligible students were invited to the study. The Movimente intervention program was performed during a school year and included 3 main components: Teacher training (including face-to-face meeting, social media platform, and handbook with lesson plans); improvements in the PA environment in school; and educational strategies. Control schools continued with their traditional schedule. Baseline (March/April 2017), postintervention (November/December 2017), and maintenance (June/July 2018) evaluations included PA and SB as primary outcomes (assessed by self-report and accelerometry). Secondary outcomes included psychosocial factors related to PA and SB (e.g., social support and self-efficacy), as well as health (e.g., quality of life and nutritional status) and education (e.g., academic achievement) outcomes. A program evaluation was performed based on the RE-AIM framework. Participants, intervention staffs, and evaluators were not blinded to group assignment, but a standardized evaluation protocol was applied independently of the trial allocation.

RESULTS

Statistical analyses will include a multilevel approach for repeated measurements and mediation analysis. Any side effects of the intervention will be recorded. The sample size close to that expected (n = 1090) was reached (n = 999). The results of this trial will involve valuable information about the effect and the evaluation of a multicomponent intervention carried out in a middle-income country.

CONCLUSION

By creating opportunities for adolescents to be active at school using multicomponent strategies, the Movimente program has the potential to enhance students health and academic performance which may encourage the school community (e.g., teachers, principals) to adopt the program. Also, this trial will provide evidence for practitioners, policy makers, and researchers on how multicomponent program may be implemented in a school setting.

TRIAL REGISTRATION

The trial is registered at the Clinical Trial Registry (Trial ID: NCT02944318; date of registration: 18 October 2016).

Interventions to control children's screen use and their effect on sleep: A systematic review and meta-analysis

Prolonged viewing of screen-based media is associated with poor sleep in children. Previous systematic reviews have analysed the effectiveness of interventions that aim to limit children's screen use; however, none have evaluated its effect on sleep. The aim of this systematic review was to evaluate the effect of interventions that incorporate strategies to control children's screen use on screen use and sleep. The databases Pubmed, Embase, Eric, Scopus and PsycInfo were searched during October 2017 and updated in February 2019 for experimental studies with a control that assessed interventions to control screen use in children aged 2-14 years and reported both screen use and sleep outcomes. From 3,872 initial records, 11 studies (six randomized control [RCT], four cluster RCT and one cluster, quasi-experimental) were eligible for inclusion. A total of 4,656 children aged 2-13 years were included in the studies. The mean reduction in screen time was 0.56 hr (33 min)/day (95% confidence interval [CI], 0.92, 0.20) and the mean sleep duration increased by 0.19 hr (11 min)/day (95% CI, 0.05, 0.33). Bedtime was advanced by 0.16 hr (10 min) on weekdays and by 1.0 hr at the weekend. Subgroup analyses indicated stronger intervention effects for interventions of shorter duration (<3 months), which specifically targeted screen use or sleep, and those with direct participant contact. In conclusion, small improvements in screen time and sleep duration can be achieved in children. It is not possible to determine if a reduction in screen time directly improves sleep, due to the limited number of studies, the presence of co-interventions, issues with studies' methodological quality and heterogeneity.

Primordial Prevention of High Blood Pressure in Childhood: An Opportunity Not to be Missed

Hypertension is a condition with increased risk for subsequent adverse events, and treatment of hypertension is prescribed for primary prevention of adverse events. Primordial prevention is a concept that precedes primary prevention and focuses on risk factor prevention. Primordial prevention of hypertension consists of strategies to maintain blood pressure in a normal range and prevent development of elevated blood pressure or hypertension. Childhood is a period in which primordial prevention could be effective and if sustained throughout childhood could contribute to a healthier young adulthood. Targets for primordial prevention in childhood include preventing and reducing childhood obesity, achieving an optimal diet that includes avoiding excessive salt consumption, and removing barriers to physical activity and healthy sleep throughout childhood. Primordial prevention also includes the prenatal period wherein some maternal conditions and exposures are associated with higher blood pressure in child offspring.

The Role of Recreational Online Activities in School-Based Screen Time Sedentary Behaviour Interventions for Adolescents: A Systematic and Critical Literature Review

Sedentary behaviours are highly associated with obesity and other important health outcomes in adolescence. This paper reviews screen time and its role within school-based behavioural interventions targeting adolescents between the years 2007 and 2019. A systematic literature review following PRISMA guidelines was conducted across five major databases to identify interventions targeting screen time—in addition to TV/DVD viewing. The review identified a total of 30 papers analysing 15 studies across 16 countries aiming at addressing reduction of recreational screen time (internet use and gaming) in addition to television/DVD viewing. All of the interventions focused exclusively on behaviour change, targeting in the majority both reduction of sedentary behaviours along with strategies to increase physical activity levels. A mix of intervention effects were found in the reviewed studies. Findings suggest aiming only for reduction in time spent on screen-based behaviour within interventions could be a limited strategy in ameliorating excessive screen use, if not targeted, in parallel, with strategies to address other developmental, contextual and motivational factors that are key components in driving the occurrence and maintenance of adolescent online behaviours. Additionally, it raises the need for a differential treatment and assessment of each online activity within the interventions due to the heterogeneity of the construct of screen time. Recommendations for enhancing the effectiveness of school-based sedentary behaviour interventions and implications for public policy are discussed.

Hábitos alimentares, atividade física e comportamento sedentário entre escolares brasileiros: Pesquisa Nacional de Saúde do Escolar, 2015

RESUMO: Introdução: A urbanização e a industrialização colaboraram para a alteração nos padrões de alimentação, bem como para o surgimento de comportamentos sedentários e a redução da atividade física. Objetivos: Identificar e descrever a prevalência de hábitos alimentares, prática de atividade física e comportamento sedentário em escolares brasileiros e analisar sua associação com as características sociodemográficas. Métodos: Foram utilizados dados da Pesquisa Nacional de Saúde do Escolar de 2015. Foram calculadas prevalências, razões de prevalências e intervalos de 95% de confiança (IC95%). As análises foram ajustadas para idade escolaridade materna. Resultados: A maioria consumia feijão (65,1%) e guloseimas (52,3%), teve mais de três dias de aula de Educação Física escolar (50,7%), realizava atividade física fora da escola por mais de três dias (55,4%), tinha comportamento sedentário (73,3%) e realizava atividade física durante 60 min/dia por menos de quatro dias na semana (72,7%). Em geral, as meninas estavam mais expostas a práticas alimentares não desejáveis e ao comportamento sedentário, e o melhor nível socioeconômico associou-se a maiores prevalências dos indicadores estudados. Elevado consumo de alimentos não saudáveis, aumento do comportamento sedentário e redução na prática de atividade física. Conclusão: Observou-se associação de atitudes não saudáveis com características sociodemográficas entre os escolares. Estratégias que foquem na redução desses comportamentos irão contribuir para ações de promoção da saúde nos ambientes escolar e familiar.

SYSTEMATIC REVIEW OF PHYSICAL ACTIVITY AND SEDENTARY BEHAVIOR INDICATORS IN SOUTH-AMERICAN PRESCHOOL CHILDREN

Objective:

To summarize indicators and describe in detail the methods used to physical activity and sedentary behavior measurement in South American preschool children.

Data source:

In 2017, we searched for articles on researches carried out in South American countries, which presented physical activity and/or sedentary behavior indicators in children aged two to six years. These searches were conducted in Spanish, English, and Portuguese in four electronic databases (LILACS, PubMed, SciELO, and Web of Science), Google Scholar, and in reference lists.

Data summary:

Out of 416 articles initially assessed, 13 composed the descriptive summary. Samples from Argentina, Brazil, and Chile were included. Three articles provided accelerometer-based estimates of moderate physical activity: 32, 70.1, and 71.3 minutes per day. The mean total sedentary behavior was 468.3 and 562.9 minutes per day and, considering the cut-off point of 2 hours per day of screen time, we found the following prevalence rates: 39.4, 40.3, and 100%. The studies adopted a wide number of instruments and strategies to evaluate those behaviors.

Conclusions:

Although the summary has pointed to high exposure to sedentary behavior in preschool children, with particular focus on screen time, it is essential to broaden the discussion and approximate the methods used to assess physical activity and sedentary behavior, making the evidence more comparable and strong, so as to elaborate preventive strategies and actions.

Screen Time: The Impact of Digital Technology on Children and Strategies in Care

Media and digital devices are an integral part of the world today. Despite potential benefits of media time, excessive or inappropriate use of technology is having a significant impact on the development and health of children. There is a relationship between increased screen time and greater risk of physical health complications, mental health concerns, and negative outcomes on cognitive, language, social, and emotional development. Successful evidence-based interventions and screening initiatives are available for reducing unhealthy media use in children. Providers need to be aware of media-use guidelines, screen for at-risk media use, and provide parental education as well as recommend interventions when indicated. [Journal of Psychosocial Nursing and Mental Health Services, 57(11), 15-20.].

Sedentary Behaviors in Today's Youth: Approaches to the Prevention and Management of Childhood Obesity: A Scientific Statement From the American Heart Association

This scientific statement is about sedentary behavior and its relationship to obesity and other cardiometabolic outcomes in youth. A deleterious effect of sedentary behavior on cardiometabolic health is most notable for screen-based behaviors and adiposity; however, this relation is less apparent for other cardiometabolic outcomes or when sedentary time is measured with objective movement counters or position monitors. Increasing trends of screen time are concerning; the portability of screen-based devices and abundant access to unlimited programming and online content may be leading to new patterns of consumption that are exposing youth to multiple pathways harmful to cardiometabolic health. This American Heart Association scientific statement provides an updated perspective on sedentary behaviors specific to modern youth and their impact on cardiometabolic health and obesity. As we reflect on implications for practice, research, and policy, what emerges is the importance of understanding the context in which sedentary behaviors occur. There is also a need to capture the nature of sedentary behavior more accurately, both quantitatively and qualitatively, especially with respect to recreational screen-based devices. Further evidence is required to better inform public health interventions and to establish detailed quantitative guidelines on specific sedentary behaviors in youth. In the meantime, we suggest that televisions and other recreational screen-based devices be removed from bedrooms and absent during meal times. Daily device-free social interactions and outdoor play should be encouraged. In addition, parents/guardians should be supported to devise and enforce appropriate screen time regulations and to model healthy screen-based behaviors.

Physical Activity Promotion: Highlights from the 2018 Physical Activity Guidelines Advisory Committee Systematic Review

PURPOSE

This article describes effective interventions to promote regular physical activity and reduce sedentary behavior that were identified as part of the 2018 Physical Activity Guidelines Advisory Committee Scientific Report.

METHODS

A comprehensive literature search was conducted of eligible systematic reviews, meta-analyses, and relevant governmental reports published between 2011 and 2016. For the physical activity promotion question, articles were first sorted by four social ecological levels of impact (i.e., individual, community, communication environment, and physical environment and policy levels) and then further sorted into more specific categories that emerged during the review process. For the sedentary behavior reduction question, the literature was sorted directly into emergent categories (i.e., youth, adult, and worksite interventions).

RESULTS

Effective physical activity promotion strategies were identified at each level of impact, including those based on behavior change theories and those occurring at different settings throughout the community. Effective interventions also included those delivered in person by trained staff or peer volunteers and through different information and communication technologies, such as by phone, Web or Internet, and computer-tailored print. A range of built environment features were associated with more transit-based and recreational physical activity in children and adults. Effective sedentary reduction interventions were found for youth and in the workplace.

CONCLUSIONS

A promising number of interventions with demonstrated effectiveness were identified. Future recommendations for research include investigating the most useful methods for disseminating them to real-world settings; incorporating more diverse population subgroups, including vulnerable and underrepresented subgroups; collecting cost data to inform cost-effectiveness comparisons; and testing strategies across different levels of impact to determine which combinations achieve the greatest effects on different modes of physical activity across the week.

Can High Schools Be an Effective Setting to Promote Healthy Lifestyles? Effects of a Multiple Behavior Change Intervention in Adolescents

PURPOSE

The main aim was to examine the effects of a school-based intervention on multiple health behaviors in adolescents, such as 24-hour movement behaviors (i.e., physical activity, sedentary time, and sleep duration), diet, and substance consumption (i.e., alcohol and tobacco). Another aim was to examine intragender differences in the effectiveness of the programme.

METHODS

A quasi-experimental design was carried out in two secondary schools throughout one academic year. A final sample of 210 students participated: 105 in the control (Mage = 13.07 ± 0.63) and 105 in the experimental school (Mage = 13.05 ± 0.59). A multicomponent school-based intervention was conducted by teachers in the experimental school via curricular (i.e., tutorial action plan, interdisciplinary project, and school break) and extracurricular (i.e., family involvement, institutional and noncurricular activities, and dissemination of health information and events) actions to promote adolescents' healthy lifestyles. Physical activity and sedentary time were measured by accelerometers, and the rest of health behaviors by using self-reported scales.

RESULTS

Experimental school students showed a significant improvement in meeting specific and general combinations of 24-hour movement guidelines, sedentary screen time levels, nap duration, (un)healthy diet scores, breakfast intake, and soft drink consumption compared to both control school students and their baseline values (p >.05). Active commuting and substance consumption rates only showed a significant improvement compared to control school students (p >.05). Although the intervention programme was effective in improving health-related behaviors in both genders, a large effect size was observed in boys.

CONCLUSIONS

Conducting multiple health behavior interventions becomes essential to improve adolescents' healthy lifestyles.

A Review of Systematic Reviews Targeting the Prevention and Treatment of Overweight and Obesity in Adolescent Populations

PURPOSE

Adolescent obesity is a powerful predictor of morbidity and mortality, yet amenable to modifiable behaviors. To accurately summarize the effects of behavioral interventions on changes in adolescent body mass index and/or weight status, we assessed existing systematic reviews for reporting transparency and methodological quality.

METHODS

Five databases were searched through September 2017 to identify relevant systematic reviews. Reviews were evaluated for reporting transparency and methodological quality using PRISMA Reporting Checklist and Assessment of Multiple Systematic Reviews Instrument. Evidence was synthesized across high-quality reviews.

RESULTS

Four of twelve systematic reviews were of high methodological quality. All four focused on the treatment of overweight/obesity in adolescent populations, representing 97 international studies. Findings indicate intervention compared with no intervention/wait list showed larger effects for improving BMI/BMI z-scores. Small improvements (averaging a 3.7-kg decrease) in weight/weight percentile were observed following a supervised exercise plus dietary and/or behavior support intervention. Health-related quality of life may improve following interventions, but overall attention to associated psychological variables (depression, self-esteem/perception) is limited.

CONCLUSIONS

Adherence to objective checklists and protocols for rigorous conduct and reporting of systematic reviews is warranted. Consensus evidence is urgently needed to define and report behavior change interventions related to obesity prevention and treatment.

Effects of School-based Health Promotion Intervention on Health Behaviors among School Adolescents in North Lima and Callao, Peru

Background

Multicomponent interventions that include both school and family or community involvements have the potential to cause significant changes in the levels of health in adolescents. To this end, KOICA and Yonsei Global Health Center implemented a school-based health promotion program from 2015 to 2016 in Northern Lima and Callao, Peru. The present study aimed to evaluate the effects of a school-based health promotion intervention on the health behaviors of school adolescents in Peru.

Methods

Health behaviors were measured using a standard self-administered questionnaire before and after the introduction of a school-based health promotion intervention in 2014 and 2016. The intervention was executed in secondary schools, specifically two schools from Lima and two from Callao, from April 2015 to November 2016. Two schools (one from each area) were selected as control schools. The interventions included health education, screening, and psychological counseling of vulnerable individuals as well as education for teachers and workshops with parents.

Results

Descriptive statistics, chi-square test results, and logistic regression values were computed. Sample sizes were 332 and 255 in 2014 and 933 and 599 in 2016 in the intervention and control schools, respectively. Logistic regression analysis revealed significant improvement in the consumption of vegetables and in depression in the intervention schools. Suicide attempts, television-watching, video game use, Internet use, consumption of chips and sugary drinks, and being in fights did not decrease in the intervention group but did increase in the control group. Thus, the intervention might have prevented the worsening of these behaviors in the intervention schools.

Conclusion

The intervention had a positive effect on vegetable consumption and feeling depressed as well as on preventing the increase in sedentary behaviors, fighting, and suicide attempts.

Effectiveness of interventions to control screen use and children's sleep, cognitive and behavioral outcomes: a systematic review protocol

REVIEW QUESTIONS.

Do school physical activity policies and programs have a role in decreasing multiple screen time behaviours among youth?

Screen time in youth has been associated with a wide range of poor health outcomes. Evidence indicates the need to develop physical activity (PA) school policies and programs that are aimed at decreasing youth screen time behaviours. This study aims to understand the association between PA policies and programs embedded into the functioning of 89 schools across two provinces in Canada and multiple screen time behaviours. As part of the COMPASS Study, a total of 44,861 youth aged between 13 and 18years and belonging to 89 schools in two Canadian provinces completed a validated questionnaire for health behaviours and outcomes data. PA policies and programs were measured using the School Policies and Practices Questionnaire, completed by the relevant school administrator. Participation in before-school, noon hour, or after-school intramural programs, participation in varsity sports, and access to indoor areas of PA during non-instructional time, was associated with significantly lower multiple screen time behaviours across both provinces. With exposure to multiple electronic and digital devices only predicted to increase among youth in the future, there is a need to conceptualize and integrate school-based screen time reducing PA policies and programs into the regular functioning of the schools.

Involving teachers in reducing children’s media risks

Purpose

The purpose of this paper is twofold: first, to introduce MEDIA PROTECT, a multi-modal intervention for parents and teachers with six components preventing problematic, and in the long run addictive, use of screen media by children; second, to present results of a formative evaluation of the teacher training, an important component of the intervention.

Design/methodology/approach

In presenting the intervention, the authors used a common framework to describe complex interventions systematically. For the evaluation, participants were recruited from German schools and kindergarten for a cluster-controlled trial. As part of a formative evaluation, the participants completed written questionnaires to determine the importance of different components of the intervention in addition to their overall satisfaction. Additional qualitative interviews with teachers were conducted.

Findings

The authors recruited n=50 kindergartens and n=9 schools; n=30 received the intervention. N=222 teachers participated in the training and n=192 completed the questionnaire (86 per cent). Seven qualitative interviews were conducted. Participants exhibited high levels of overall satisfaction with the training, considered it moderately to highly relevant to their work, and exhibited varying satisfaction levels with different components and multipliers. The qualitative data support these findings.

Originality/value

Few interventions to date have pursued a universal approach to the prevention of problematic screen media use. This evaluation of MEDIA PROTECT is the most recent study in Germany, which involves a complex programme through which teachers are taught ways to promote the age-adequate use of screen media in the family, parents are provided with guidance and healthy leisure time activities for children are fostered.

Effects of a Randomised Controlled School-Based Health Promotion Intervention on Obesity Related Behavioural Outcomes of Children with Migration Background

Children with migration background (MB) appear to be at higher risk of developing obesity, therefore, prevention is necessary to avoid possible health inequalities. This study investigated a 1-year intervention with focus on increasing physical activity (PA) and fruit and vegetable intake (FVI), decreasing screen media use (SMU) and soft drink consumption (SDC) in children with MB. 525 children (7.1 ± 0.7 years) with MB who participated in the cluster-randomised study were assessed at baseline and after 1 year. Daily SMU, PA behaviours, SDC and FVI were assessed using a parental questionnaire. After one year, significant effects were found in the intervention group for FVI (p ≤ 0.035). Partially strong tendencies but no significant differences were found for PA and SDC. Although the effects are small, the intervention seems to reach children with MB. An intervention lasting longer than one year might result in more changes.

Sedentary behavior among Spanish children and adolescents: findings from the ANIBES study

Background

An increase of sedentary behaviors far from the Mediterranean lifestyle is happening in spite of the impact on health. The aims of this study were to describe sedentary behaviors in children and adolescents.

Methods

A representative sample of 424 Spanish children and adolescents (38% females) involved in the ANIBES study was analyzed regarding their sedentary behaviors, together with the availability of televisions, computers, and consoles by means of the HELENA sedentary behavior questionnaire.

Results

For the total sample of children, 49.3% during weekdays and 84% during weekends did not meet the recommendation of less than 2 hours of screen viewing per day. The use of TV was higher during weekdays (p < 0.05) and there were significant differences between adolescents and children (16.9 vs. 25.1%, p < 0.05). The use of computer, console games and of internet for non-study reasons was higher during weekends (p < 0.001). Adolescents played more computer games and used more internet for non-study reasons than children during both weekdays and weekends (p < 0.05 and p < 0.001, respectively). The use of internet for academic reasons was lower in children (p < 0.001) than adolescents during weekends; however, no significant differences were found between sexes. In addition, more than 30% of the children and adolescents had at least one electronic device in their bedrooms.

Conclusions

Spanish children and adolescents are not meeting the recommendations regarding the maximum of screen viewing (<2 h/day), especially during the weekend, for all of sedentary behaviors. Urgent strategies and intervention studies are needed to reduce sedentary behavior in young people.

'Life in the age of screens': parent perspectives on a 24-h no screen-time challenge

Screens have become ubiquitous in modern society. Their use frequently underlies sedentary behaviour, a well-established determinant of obesity. As part of a family oriented clinic offering a 2-year lifestyle program for obese children and youth, we explored parents' experiences with a 24-h no screen-time challenge, an intervention designed to raise awareness of screen-time habits and to help families develop strategies to limit their use. In total, 15 parents representing 13 families participated. A focus group with nine parents and six phone interviews with those who could not join in person were conducted. Interviews were transcribed verbatim and analysed qualitatively. Key elements to successful completion of the 24-h no screen-time challenge emerged, namely: clear rules about permitted activities during the 24-h period; togetherness, i.e. involving all family members in the challenge; and busyness, i.e. planning a full schedule in order to avoid idleness and preclude the temptation to use screens. Our findings suggest that practitioners aiming to increase awareness of screen-time or to limit their use may be more likely to succeed if they include all family members, offer concrete alternatives to screen-based activities and provide tailored strategies to manage discretionary time.

Effectiveness of intervention strategies exclusively targeting reductions in children's sedentary time: a systematic review of the literature

An increasing number of interventions targeting sedentary behaviour in children have emerged in recent years. Recently published reviews included sedentary behaviour and physical activity interventions. This review critically summarizes evidence on the effectiveness of intervention strategies that exclusively targeted reducing sedentary time in children and adolescents. We performed a systematic literature search in Pubmed, Embase and the Cochrane Library through November 2015. Two independent reviewers selected eligible studies, extracted relevant data and rated the methodological quality using the assessment tool for quantitative studies. We included 21 intervention studies, of which 8 studies scored moderate on methodological quality and 13 studies scored weak. Four out of eight moderate quality studies reported significant beneficial intervention effects.Although descriptions of intervention strategies were not always clearly reported, we identified encouragement of a TV turnoff week and implementing standing desks in classrooms as promising strategies. Due to a lack of high quality studies and inconsistent findings, we found no convincing evidence for the effectiveness of existing interventions targeting solely sedentary behaviour. We recommend that future studies apply mediation analyses to explore which strategies are most effective. Furthermore, to increase the effectiveness of interventions, knowledge of children's motives to engage in sedentary behavior is required, as well as their opinion on potentially effective intervention strategies.

Sedentary behavior in Brazilian children and adolescents: a systematic review

OBJECTIVE

To describe the methodological characteristics of the studies selected and assess variables associated with sedentary behavior in Brazilian children and adolescents.

METHODS

For this systematic review, we searched four electronic databases: PubMed, Web of Knowledge, LILACS, SciELO. Also, electronic searches were applied in Google Scholar. A supplementary search was conducted in the references lists of the included articles and in non-indexed journals. We included observational studies with children and adolescents aged from three to 19 years developed in Brazil, presenting analyses of associations based on regression methods and published until September 30, 2014.

RESULTS

Of the 255 potential references retrieved by the searches, 49 met the inclusion criteria and composed the descriptive synthesis. In this set, we identified a great number of cross-sectional studies (n = 43; 88.0%) and high methodological variability on the types of sedentary behavior assessed, measurement tools and cut-off points used. The variables most often associated with sedentary behavior were "high levels of body weight" (in 15 out of 27 studies; 55.0%) and "lower level of physical activity" (in eight out of 16 studies; 50.0%).

CONCLUSIONS

The findings of this review raise the following demands to the Brazilian agenda of sedentary behavior research geared to children and adolescents: development of longitudinal studies, validation of measuring tools, establishment of risk cut-offs, measurement of sedentary behavior beyond screen time and use of objective measures in addition to questionnaires. In the articles available, the associations between sedentary behavior with "high levels of body weight" and "low levels of physical activity" were observed in different regions of Brazil.

ERICA: use of screens and consumption of meals and snacks by Brazilian adolescents

OBJECTIVE To describe the length of exposure to screens and the prevalence of consumption of meals and snacks by Brazilian adolescents in front of screens. METHODS We evaluated 74,589 12 to 17-year old adolescents from 1,247 schools in 124 Brazilian municipalities. A self-administered questionnaire was used. Its segment regarding nutrition contained questions about using TV, computers, and video game systems, having meals while watching TV, and consuming snacks in front of screens. Consumption of meals and snacks in front of screens was analyzed according to the following variables: geographical region, gender, age range, type of school (public or private), and school shift. The prevalences and their respective 95% confidence intervals were estimated under a complex sampling design. RESULTS A great deal of the adolescents (51.8% IC95% 50.7-53.0) [corrected] reported spending two or more hours a day in front of screens. That habit was more frequent among male adolescents, private school students, morning shift students, and students from Brazil's South region. More than half of the adolescents (56.6%, 95%CI 55.4-57.8) reported almost always or always having meals in front of TV, and 39.6% (95%CI 38.8-40.5) of them said they consumed snacks in front of screens exactly as often. Both situations were the most prevalent ones among the girls, who attended public schools and were from Brazil's Midwest region. CONCLUSIONS Length of exposure to screens and consumption of meals and snacks almost always or always in front of screens are high among Brazilian adolescents. It is necessary to develop strategies aiming to reduce the length of screen use, considering the media reality that children and adolescents have been experiencing from earlier and earlier ages. That context must therefore be analyzed in an indissociable way.

MEDIDA DA ATIVIDADE FÍSICA EM JOVENS BRASILEIROS: REPRODUTIBILIDADE E VALIDADE DO PAQ-C E DO PAQ-A

Introdução: O Physical Activity Questionnaire for Children (PAQ-C) e o Physical Activity Questionnaire for Adolescents (PAQ-A) foram originalmente propostos para oferecer medidas autorrelatadas da prática de atividade física de jovens. Objetivos: Traduzir para o idioma português, realizar adaptação transcultural e analisar reprodutibilidade e validade concorrente do PAQ-C e do PAQ-A em amostra de jovens brasileiros. Métodos: Versões originais foram traduzidas de acordo com recomendações internacionais. Os questionários traduzidos foram administrados em amostra de 528 jovens (285 moças e 243 rapazes) com idades entre oito e 18 anos. Reprodutibilidade foi obtida por intermédio de réplicas de aplicação dos questionários, com intervalo de uma semana, envolvendo coeficiente de correlação intraclasse (CCI) e técnica de Bland-Altman. A consistência interna foi analisada mediante coeficiente alfa de Cronbach. Para análise da validade concorrente foram consideradas informações apresentadas pelo acelerômetro RT3 durante sete dias como critério de referência. Atividade física total (AFtotal) e atividade física de intensidades moderada a vigorosa (AFMV) derivadas do acelerômetro foram comparadas mediante coeficiente de correlação de Spearman com pontuações apresentadas pelos questionários. Resultados: Após discretas modificações apontadas no processo de tradução, um comitê de juízes considerou que as versões traduzidas do PAQ-C e do PAQ-A apresentaram equivalências semântica, idiomática, cultural e conceitual. Reprodutibilidade teste-reteste mostrou CCI entre 0,68 e 0,88. A técnica de Bland-Altman evidenciou elevada capacidade de concordância entre réplicas de aplicação dos questionários. A consistência interna mostrou α = 0,71 e α = 0,76, respectivamente. A pontuação dos questionários demostrou correlações moderadas com AFtotal (rho = 0,40; rho = 0,50) e AFMV (rho = 0,48; rho = 0,54) estimadas pelo acelerômetro. Conclusão: A tradução, adaptação transcultural, reprodutibilidade e validade concorrente do PAQ-C e do PAQ-A foram satisfatórias, o que viabiliza sua aplicação em futuros estudos no Brasil.

School-based intervention on healthy behaviour among Ecuadorian adolescents: effect of a cluster-randomized controlled trial on screen-time

Background

Effective interventions on screen-time behaviours (television, video games and computer time) are needed to prevent non-communicable diseases in low- and middle-income countries. The present manuscript investigates the effect of a school-based health promotion intervention on screen-time behaviour among 12- to 15-year-old adolescents. We report the effect of the trial on screen-time after two stages of implementation.

Methods

We performed a cluster-randomised pair matched trial in urban schools in Cuenca-Ecuador. Participants were adolescents of grade eight and nine (mean age 12.8 ± 0.8 years, n = 1370, control group n = 684) from 20 schools (control group n = 10). The intervention included an individual and environmental component tailored to the local context and resources. The first intervention stage focused on diet, physical activity and screen-time behaviour, while the second stage focused only on diet and physical activity. Screen-time behaviours, primary outcome, were assessed at baseline, after the first (18 months) and second stage (28 months). Mixed linear models were used to analyse the data.

Results

After the first stage (data from n = 1224 adolescents; control group n = 608), the intervention group had a lower increase in TV-time on a week day (β = −15.7 min; P = 0.003) and weekend day (β = −18.9 min; P = 0.005), in total screen-time on a weekday (β = −25.9 min; P = 0.03) and in the proportion of adolescents that did not meet the screen-time recommendation (β = −4 percentage point; P = 0.01), compared to the control group. After the second stage (data from n = 1078 adolescents; control group n = 531), the TV-time on a weekday (β = 13.1 min; P = 0.02), and total screen-time on a weekday (β = 21.4 min; P = 0.03) increased more in adolescents from the intervention group. No adverse effects were reported.

Discussion and Conclusion

A multicomponent school-based intervention was only able to mitigate the increase in adolescents’ television time and total screen-time after the first stage of the intervention or in other words, when the intervention included specific components or activities that focused on reducing screen-time. After the second stage of the intervention, which only included components and activities related to improve healthy diet and physical activity and not to decrease the screen-time, the adolescents increased their screen-time again. Our findings might imply that reducing screen-time is only possible when the intervention focuses specifically on reducing screen-time.

Trial registration

Clinicaltrials.gov identifier NCT01004367.

Screen time impairs the relationship between physical fitness and academic attainment in children

OBJECTIVE

The purpose of this study was twofold: to analyze the association between physical fitness and academic attainment, and to determine the influence of screen time on the association between physical fitness and academic attainment.

METHODS

A cross-sectional study including 395 schoolchildren from seven schools of the Maule Region, Chile (mean age 12.1 years; 50.4% boys) participated in the autumn of 2014 (March to June). Self-reported physical activity and screen time were evaluated. The study measured academic achievement (mean of the grades obtained in several core subjects), physical fitness (cardiorespiratory fitness and muscular strength), weight, height, parental education, and socioeconomic status. Linear regression analysis was used to analyze the relationships between physical fitness and academic attainment after adjusting for potential confounders by gender. Analysis of variance was used to analyze the differences in academic attainment according to fitness and screen time categories (< 2 hours/day and ≥ 2 hours/day).

RESULTS

In both genders good cardiorespiratory fitness levels were associated with high language (β=0.272-0.153) and mean academic attainment (β=0.192-0.156) grades; however, after adjusting for screen time and other potential confounders, these associations disappear. Similarly, no relationship was observed after analyzing those children who spend more hours of screen time (≥ 2 hours/day).

CONCLUSIONS

Academic attainment is associated with higher cardiorespiratory fitness levels; however, it was weakly impaired by screen time. These findings seem to suggest that parents and policymakers should minimize the negative effects of screen time on children's lives to maximize the beneficial effect of healthy habits on academic attainment.

Television viewing habits and their influence on physical activity and childhood overweight

OBJECTIVES

To assess the prevalence of television (TV) viewing habits and their association with childhood sedentary lifestyle and overweight in 8-year-old children, from a cohort in a city in Southern Brazil.

METHODS

A prospective cohort study with hospital screening of all births that occurred from September of 2002 to May of 2003. This study refers to a cross-sectional analysis of data collected during the cohort's follow-up conducted at 8 years of age. To evaluate the level of physical activity, a physical activity questionnaire for children and adolescents was used (PAQ-C), during the consultation at 8 years of age.

RESULTS

Of the 616 interviewed children, a prevalence of sedentary lifestyle>70% was found, as well as the habit of watching TV for more than two hours a day in 60% of the sample, regardless of gender (p=0.30), income (p=0.57), or family socioeconomic level (p=0.90). The daily time spent watching TV was inversely associated with physical activity (p<0.05) and positively associated with excess weight (p<0.01). Regarding physical activity, running was the most frequently practiced sports modality among the population.

CONCLUSIONS

Considering the high prevalence of sedentary lifestyle and children who watch TV for an excessive period of time, it is necessary to motivate such individuals to perform interactive activities, as well as promote a more active lifestyle, by decreasing the time children spend in front of the TV.

The Dutch Obesity Intervention in Teenagers (DOiT) cluster controlled implementation trial: intervention effects and mediators and moderators of adiposity and energy balance-related behaviours

Background

The Dutch Obesity Intervention in Teenagers (DOiT) programme is an evidence-based obesity prevention programme tailored to adolescents attending the first two years of prevocational education in the Netherlands. The initial programme showed promising results during an effectiveness trial. The programme was adapted and prepared for nationwide dissemination. To gain more insight into the process of translating evidence-based approaches into ‘real world’ (i.e., ‘natural’) conditions, our research aims were to evaluate the impact of the DOiT-implementation programme on adolescents’ adiposity and energy balance-related behaviours during natural dissemination and to explore the mediating and moderating factors underlying the DOiT intervention effects.

Methods

We conducted a cluster-controlled implementation trial with 20 voluntary intervention schools (n=1002 adolescents) and 9 comparable control schools (n = 484 adolescents). We measured adolescents’ body height and weight, skinfold thicknesses, and waist circumference. We assessed adolescents’ dietary and physical activity behaviours by means of self-report. Data were collected at baseline and at 20-months follow-up. We used multivariable multilevel linear or logistic regression analyses to evaluate the intervention effects and to test the hypothesised behavioural mediating factors. We checked for potential effect modification by gender, ethnicity and education level.

Results

We found no significant intervention effects on any of the adiposity measures or behavioural outcomes. Furthermore, we found no mediating effects by any of the hypothesised behavioural mediators. Stratified analyses for gender showed that the intervention was effective in reducing sugar-containing beverage consumption in girls (B = -188.2 ml/day; 95% CI = -344.0; -32.3). In boys, we found a significant positive intervention effect on breakfast frequency (B = 0.29 days/week; 95% CI = 0.01; 0.58). Stratified analyses for education level showed an adverse intervention effect (B = 0.09; 95% CI = 0.02; 0.16) on BMI z-scores for adolescents attending the vocational education track.

Conclusions

Although not successful in changing adolescents’ adiposity, the DOiT-implementation programme had some beneficial effects on specific obesity-related behaviours in subgroups. This study underlines the difficulty of translating intervention effectiveness in controlled settings to real world contexts. Adaptations to the implementation strategy are needed in order to promote implementation as intended by the teachers.

Trial registration

Current Controlled Trials ISRCTN92755979.

Electronic supplementary material

The online version of this article (doi:10.1186/s12966-014-0158-0) contains supplementary material, which is available to authorized users.

Intervention effects of a school-based health promotion programme on obesity related behavioural outcomes

Studies have shown preventive effects of an active lifestyle during childhood on later life; therefore, health promotion has to start early. The programme "Join the Healthy Boat" promotes a healthy lifestyle in primary school children. In order to evaluate it, children's behaviours in respect of increased physical activity (PA), a decrease in screen media use (SMU), more regular breakfast, and a reduction of the consumption of soft drinks (SDC) were investigated. 1943 children (7.1 ± 0.6 years) participated in the cluster-randomised study and were assessed at baseline and 1736 of them at follow-up. Teachers delivered lessons, which included behavioural contracting and budgeting of SMU and SDC. Daily SMU, PA behaviours, SDC, and breakfast patterns were assessed via parental questionnaire. After one-year intervention, significant effects were found in the intervention group for SMU of girls, children without migration background, and children with parents having a low education level. In the control group, second grade children skipped breakfast significantly more often. Tendencies but no significant differences were found for PA and SDC. This intervention seems to affect groups, which are usually hard to reach, such as children of parents with low education levels, which shows that active parental involvement is vital for successful interventions.