Netherlands Research programme weight Gain prevention (NHF-NRG): rationale, objectives and strategies

Predictors of Self-Determined Module Choice in a Web-Based Computer-Tailored Diet and Physical Activity Intervention: Secondary Analysis of Data From a Randomized Controlled Trial

Background

Tailoring an online intervention to participant preferences (eg, by giving participants a choice which modules to follow) may increase engagement in the intervention, motivation for behavioral change, and possibly intervention effects. So far, little is known about what characteristics predict these module choices. Filling this knowledge gap is useful for optimizing program engagement.

Objective

We investigated participant choice for a dietary and/or physical activity (PA) promotion module in our web-based computer-tailored intervention based on self-determination theory (SDT) and motivational interviewing (MI). Furthermore, we investigated which demographic characteristics, current behavior, psychosocial constructs and constructs from SDT and MI, and program-related variables such as advice on which module to follow were associated with these choices.

Methods

Observational data were used from the randomized controlled trial MyLifestyleCoach of participants who were randomized into the intervention condition, completed the baseline questionnaire, and made a module choice in the opening session of the intervention. Here, they received advice on their own dietary and PA behavior. At the session’s end, they chose which lifestyle modules they would like to follow (both, diet, PA, or no module). Measurements included demographic information; self-reported diet and PA; and several psychosocial, SDT, and MI constructs. In total, data from 619 Dutch adults (59.6% women; mean age was 51.9 [SD 13.5] years) were analyzed. A stepwise multinomial logistic regression analysis was conducted to investigate which characteristics are related to module choice; the diet module served as reference category as almost everyone was advised to follow this module.

Results

Of this sample, 54.8% (339/619) chose to do both the diet and PA module, 25.4% (157/619) chose to follow the diet module, 17.8% (110/619) preferred to follow no module, and 2.1% (13/619) chose to do the PA module only. Furthermore, it was found that older people, those who consumed more fruit, and those who scored lower on importance to change their current diet were more likely to choose no module compared to the diet module. People who had more motivation to change their current PA and those who received strong advice compared with slight advice to follow the diet module were more likely to choose both modules compared with the diet module only.

Conclusions

The results show that more than half of the sample was interested in following both the diet and PA module in this online lifestyle intervention. Several characteristics were found to be related to module choice. A future challenge is to examine how this knowledge can be used to improve future interventions, such as tailoring (messages or content) on specific groups or examining where and how MI could be used to motivate people to make a certain module choice.

Trial Registration

Netherlands Trial Register NL7333; https://www.trialregister.nl/trial/7333

A systematic review and meta-analysis of the overall effects of school-based obesity prevention interventions and effect differences by intervention components

BACKGROUND

Childhood obesity is a serious public health concern. School-based interventions hold great promise to combat the rising trend of childhood obesity. This systematic review aimed to assess the overall effects of school-based obesity prevention interventions, and to investigate characteristics of intervention components that are potentially effective for preventing childhood obesity.

METHODS

We systematically searched MEDLINE, CENTRAL and Embase databases to identify randomized- or cluster randomized- controlled trials of school-based obesity interventions published between 1990 and 2019. We conducted meta-analyses and subgroup analyses to determine the overall effects of obesity prevention programs and effect differences by various characteristics of intervention components on body mass index (BMI) or BMI Z-score of children.

RESULTS

This systematic review included a total of 50 trials (reported by 56 publications). Significant differences were found between groups on BMI (- 0.14 kg/m2 (95% confidence interval: - 0.21, - 0.06)) and BMI Z-score (- 0.05 (- 0.10, - 0.01)) for single-component interventions; significant differences were also found between groups on BMI (- 0.32 (- 0.54, - 0.09) kg/m2) and BMI Z-score (- 0.07 (- 0.14, - 0.001)) for multi-component interventions. Subgroup analyses consistently demonstrated that effects of single-component (physical activity) interventions including curricular sessions (- 0.30 (- 0.51, - 0.10) kg/m2 in BMI) were stronger than those without curricular sessions (- 0.04 (- 0.17, 0.09) kg/m2 in BMI); effects of single-component (physical activity) interventions were also strengthened if physical activity sessions emphasized participants' enjoyment (- 0.19 (- 0.33, - 0.05) kg/m2 in BMI for those emphasizing participants' enjoyment; - 0.004 (- 0.10, 0.09) kg/m2 in BMI for those not emphasizing participants' enjoyment). The current body of evidence did not find specific characteristics of intervention components that were consistently associated with improved efficacy for multi-component interventions (P > 0.05).

CONCLUSIONS

School-based interventions are generally effective in reducing excessive weight gain of children. Our findings contribute to increased understandings of potentially effective intervention characteristics for single-component (physical activity) interventions. The impact of combined components on effectiveness of multi-component interventions should be the topic of further research. More high-quality studies are also needed to confirm findings of this review.

Tailored eHealth Lifestyle Promotion: Which Behavioral Modules Do Users Prefer?

Health risk behaviors are widespread among adults and often co-occur. eHealth computer-tailored technology provides individuals with personalized feedback regarding multiple lifestyle behaviors. First, the authors investigated individuals' preferences for particular lifestyle modules and hypothesised that health preventive behavior modules would be preferred over addictive behavior modules. Second, characteristics associated with these choices were examined. A web-based questionnaire assessed demographics, health status, and five lifestyle behaviors (i.e., physical activity, fruit consumption, vegetable consumption, alcohol intake and tobacco use) among adults (N = 1,828). Responses were translated into a health risk appraisal outlining whether respondents adhered to the national guidelines for these behaviors. Next, respondents could select one of the lifestyle modules providing personalized advice. More than 60% of the participants failed to meet the guidelines for more than one lifestyle behavior. The physical activity module was the most popular, followed by the smoking and fruit modules. Young adults tended to prefer the physical activity and fruit modules, whereas the vegetable module was more popular among older adults. No consistent pattern was identified for the alcohol and smoking modules. The results support the authors' hypothesis that health preventive behaviors-in particular, physical activity-would be preferred. Although this could imply that physical activity could serve as a gateway behavior when aiming at multiple behavior changes, it is also conceivable that other mechanisms, such as the actual success of behavior change, or the fact that people can choose, may increase chances of multiple behavior change. Hence, mechanisms leading to multiple behavior change need to be further explored.

School-based physical activity programs for promoting physical activity and fitness in children and adolescents aged 6 to 18

BACKGROUND

The World Health Organization (WHO) estimates that 1.9 million deaths worldwide are attributable to physical inactivity and at least 2.6 million deaths are a result of being overweight or obese. In addition, WHO estimates that physical inactivity causes 10% to 16% of cases each of breast cancer, colon, and rectal cancers as well as type 2 diabetes, and 22% of coronary heart disease and the burden of these and other chronic diseases has rapidly increased in recent decades.

OBJECTIVES

The purpose of this systematic review was to summarize the evidence of the effectiveness of school-based interventions in promoting physical activity and fitness in children and adolescents.

SEARCH METHODS

The search strategy included searching several databases to October 2011. In addition, reference lists of included articles and background papers were reviewed for potentially relevant studies, as well as references from relevant Cochrane reviews. Primary authors of included studies were contacted as needed for additional information.

SELECTION CRITERIA

To be included, the intervention had to be relevant to public health practice (focused on health promotion activities), not conducted by physicians, implemented, facilitated, or promoted by staff in local public health units, implemented in a school setting and aimed at increasing physical activity, included all school-attending children, and be implemented for a minimum of 12 weeks. In addition, the review was limited to randomized controlled trials and those that reported on outcomes for children and adolescents (aged 6 to 18 years). Primary outcomes included: rates of moderate to vigorous physical activity during the school day, time engaged in moderate to vigorous physical activity during the school day, and time spent watching television. Secondary outcomes related to physical health status measures including: systolic and diastolic blood pressure, blood cholesterol, body mass index (BMI), maximal oxygen uptake (VO2max), and pulse rate.

DATA COLLECTION AND ANALYSIS

Standardized tools were used by two independent reviewers to assess each study for relevance and for data extraction. In addition, each study was assessed for risk of bias as specified in the Cochrane Handbook for Systematic Reviews of Interventions. Where discrepancies existed, discussion occurred until consensus was reached. The results were summarized narratively due to wide variations in the populations, interventions evaluated, and outcomes measured.

MAIN RESULTS

In the original review, 13,841 records were identified and screened, 302 studies were assessed for eligibility, and 26 studies were included in the review. There was some evidence that school-based physical activity interventions had a positive impact on four of the nine outcome measures. Specifically positive effects were observed for duration of physical activity, television viewing, VO2 max, and blood cholesterol. Generally, school-based interventions had little effect on physical activity rates, systolic and diastolic blood pressure, BMI, and pulse rate. At a minimum, a combination of printed educational materials and changes to the school curriculum that promote physical activity resulted in positive effects.In this update, given the addition of three new inclusion criteria (randomized design, all school-attending children invited to participate, minimum 12-week intervention) 12 of the original 26 studies were excluded. In addition, studies published between July 2007 and October 2011 evaluating the effectiveness of school-based physical interventions were identified and if relevant included. In total an additional 2378 titles were screened of which 285 unique studies were deemed potentially relevant. Of those 30 met all relevance criteria and have been included in this update. This update includes 44 studies and represents complete data for 36,593 study participants. Duration of interventions ranged from 12 weeks to six years.Generally, the majority of studies included in this update, despite being randomized controlled trials, are, at a minimum, at moderate risk of bias. The results therefore must be interpreted with caution. Few changes in outcomes were observed in this update with the exception of blood cholesterol and physical activity rates. For example blood cholesterol was no longer positively impacted upon by school-based physical activity interventions. However, there was some evidence to suggest that school-based physical activity interventions led to an improvement in the proportion of children who engaged in moderate to vigorous physical activity during school hours (odds ratio (OR) 2.74, 95% confidence interval (CI), 2.01 to 3.75). Improvements in physical activity rates were not observed in the original review. Children and adolescents exposed to the intervention also spent more time engaged in moderate to vigorous physical activity (with results across studies ranging from five to 45 min more), spent less time watching television (results range from five to 60 min less per day), and had improved VO2max (results across studies ranged from 1.6 to 3.7 mL/kg per min). However, the overall conclusions of this update do not differ significantly from those reported in the original review.

AUTHORS' CONCLUSIONS

The evidence suggests the ongoing implementation of school-based physical activity interventions at this time, given the positive effects on behavior and one physical health status measure. However, given these studies are at a minimum of moderate risk of bias, and the magnitude of effect is generally small, these results should be interpreted cautiously. Additional research on the long-term impact of these interventions is needed.

A mixed methods process evaluation of the implementation of JUMP-in, a multilevel school-based intervention aimed at physical activity promotion

BACKGROUND

The aim of the present study was to investigate factors influencing the adoption, implementation, and institutionalization process of JUMP-in-a multilevel school-based physical activity promotion program-to optimize the dissemination of the intervention and improve its effectiveness. The process evaluation concerned the constraints and success and failure factors at sociopolitical, organizational, user, and intervention levels.

METHODS

A mixed methods approach including qualitative and quantitative data was conducted during two school years (2006-2008).

RESULTS

JUMP-in was successfully embedded in the Amsterdam municipal policy and in the organizational structure and daily practices of the sectors involved. A general impeding factor was the complexity of the multilevel programme requiring multidisciplinary collaboration between organizations. In addition, there was a discrepancy between the recommendation to standardize and simplify the innovation and the need to tailor the strategies to local environmental, social, and cultural aspects.

CONCLUSIONS

This process evaluation provides challenges and remedies for managing discrepancies between prerequisites for an effective innovation and demands of daily implementation practice. The main recommendations are (a) standardized, simplified guidelines; (b) stepwise implementation; (c) formalized coalitions, integration of policy, and synchronization of tasks and protocols; and (d) smart planning and control by clear communication and feedback instruments. If these recommendations are incorporated into the JUMP-in intervention and organization, increased effectiveness and long-term effects can be expected.

Understanding determinants of nutrition, physical activity and quality of life among older adults: the Wellbeing, Eating and Exercise for a Long Life (WELL) study

Background

Nutrition and physical activity are major determinants of health and quality of life; however, there exists little research focusing on determinants of these behaviours in older adults. This is important, since just as these behaviours vary according to subpopulation, it is likely that the determinants also vary. An understanding of the modifiable determinants of nutrition and physical activity behaviours among older adults to take into account the specific life-stage context is required in order to develop effective interventions to promote health and well-being and prevent chronic disease and improve quality of life.

Methods

The aim of this work is to identify how intrapersonal, social and environmental factors influence nutrition and physical activity behaviours among older adults living in urban and rural areas. This study is a cohort study of adults aged 55-65 years across urban and rural Victoria, Australia. Participants completed questionnaires at baseline in 2010 and will complete follow-up questionnaires in 2012 and 2014. Self-report questionnaires will be used to assess outcomes such as food intake, physical activity and sedentary behaviours, anthropometry and quality of life. Explanatory variables include socioeconomic position, and measures of the three levels of influence on older adults’ nutrition and physical activity behaviours (intrapersonal, social and perceived environmental influences).

Discussion

Obesity and its determinant behaviours, physical inactivity and poor diet are major public health concerns and are significant determinants of the quality of life among the ageing population. There is a critical need for a better understanding of the determinants of nutrition and physical activity in this important target group. This research will provide evidence for the development of effective policies and programs to promote and support increased physical activity and healthy eating behaviours among older adults.

Interactive computer-based interventions for weight loss or weight maintenance in overweight or obese people

BACKGROUND

The World Health Organization (WHO) estimates that the number of obese or overweight individuals worldwide will increase to 1.5 billion by 2015. Chronic diseases associated with overweight or obesity include diabetes, heart disease, hypertension and stroke.

OBJECTIVES

To assess the effects of interactive computer-based interventions for weight loss or weight maintenance in overweight or obese people.

SEARCH METHODS

We searched several electronic databases, including CENTRAL, MEDLINE, EMBASE, CINAHL, LILACS and PsycINFO, through 25 May 2011. We also searched clinical trials registries to identify studies. We scanned reference lists of included studies and relevant systematic reviews.

SELECTION CRITERIA

Studies were included if they were randomized controlled trials or quasi-randomized controlled trials that evaluated interactive computer-based weight loss or weight maintenance programs in adults with overweight or obesity. We excluded trials if the duration of the intervention was less than four weeks or the loss to follow-up was greater than 20% overall.

DATA COLLECTION AND ANALYSIS

Two authors independently extracted study data and assessed risk of bias. Where interventions, control conditions, outcomes and time frames were similar between studies, we combined study data using meta-analysis.

MAIN RESULTS

We included 14 weight loss studies with a total of 2537 participants, and four weight maintenance studies with a total of 1603 participants. Treatment duration was between four weeks and 30 months. At six months, computer-based interventions led to greater weight loss than minimal interventions (mean difference (MD) -1.5 kg; 95% confidence interval (CI) -2.1 to -0.9; two trials) but less weight loss than in-person treatment (MD 2.1 kg; 95% CI 0.8 to 3.4; one trial). At six months, computer-based interventions were superior to a minimal control intervention in limiting weight regain (MD -0.7 kg; 95% CI -1.2 to -0.2; two trials), but not superior to infrequent in-person treatment (MD 0.5 kg; 95% -0.5 to 1.6; two trials). We did not observe consistent differences in dietary or physical activity behaviors between intervention and control groups in either weight loss or weight maintenance trials. Three weight loss studies estimated the costs of computer-based interventions compared to usual care, however two of the studies were 11 and 28 years old, and recent advances in technology render these estimates unlikely to be applicable to current or future interventions, while the third study was conducted in active duty military personnel, and it is unclear whether the costs are relevant to other settings. One weight loss study reported the cost-effectiveness ratio for a weekly in-person weight loss intervention relative to a computer-based intervention as USD 7177 (EUR 5678) per life year gained (80% CI USD 3055 to USD 60,291 (EUR 2417 to EUR 47,702)). It is unclear whether this could be extrapolated to other studies. No data were identified on adverse events, morbidity, complications or health-related quality of life.

AUTHORS' CONCLUSIONS

Compared to no intervention or minimal interventions (pamphlets, usual care), interactive computer-based interventions are an effective intervention for weight loss and weight maintenance. Compared to in-person interventions, interactive computer-based interventions result in smaller weight losses and lower levels of weight maintenance. The amount of additional weight loss, however, is relatively small and of brief duration, making the clinical significance of these differences unclear.

Changes in skinfold thickness and waist circumference after 12 and 24 months resulting from the NHF-NRG In Balance-project

Background

More knowledge is needed regarding the effectiveness of weight gain prevention programmes. The present study tested the 12-and 24-month effectiveness of the 'Netherlands Research programme weight Gain prevention' (NHF-NRG)-In Balance-project, a worksite-based intervention aimed at the prevention of weight gain.

Methods

Twelve worksites (n = 553 participants) were matched and assigned to either intervention or control group. The worksites and employees of the intervention group received individual (i.e. pedometer, computer-tailored advice) and environmental (i.e. changes in worksite canteen) interventions, directed at physical activity and food intake over 1-year. Differences between the intervention and control group in changes in body weight, BMI, skinfold thickness and waist circumference at 12 and 24 months were examined using multilevel linear regression analyses adjusting for various baseline characteristics (age, gender, BMI, marital status, education and smoking status).

Results

A significant greater reduction in skinfold thickness was found in the intervention group than in the control group, both after 12-and 24 months (Unstandardized regression coefficients (B) = -2.52, 95% C.I. -4.58, -0.45; p = 0.018; B = -4.83, 95% C.I. 6.98, -2.67; p < 0.001 respectively). Significant differences were also observed for changes in waist circumferences both at 12 months (B = -1.50, 95% C.I. -2.35, -0.65; p < 0.001) and at 24 months (B = -1.30, 95% C.I. -2.18, -0.42; p = 0.005). No significant changes were observed for weight and BMI.

Conclusions

The project was effective with regard to changes in skinfold thickness and waist circumference both at 12 and 24 months. It supports the usefulness of worksite-based prevention, especially regarding maintenance of behavioral changes.

Effect of an individually tailored one-year energy balance programme on body weight, body composition and lifestyle in recent retirees: a cluster randomised controlled trial

Background

The increased prevalence of overweight and obesity warrants preventive actions, particularly among people in transitional stages associated with lifestyle changes, such as occupational retirement. The purpose is to investigate the effect of a one year low-intensity computer-tailored energy balance programme among recent retirees on waist circumference, body weight and body composition, blood pressure, physical activity and dietary intake.

Methods

A randomised controlled trial was conducted among recent retirees (N = 413; mean age 59.5 years). Outcome measures were assessed using anthropometry, bio-impedance, blood pressure measurement and questionnaires.

Results

Waist circumference, body weight and blood pressure decreased significantly in men of the intervention and control group, but no significant between-group-differences were observed at 12 or at 24-months follow-up. A significant effect of the programme was only observed on waist circumference (-1.56 cm (95%CI: -2.91 to -0.21)) at 12 month follow up among men with low education (n = 85). Physical activity and dietary behaviours improved in both the intervention and control group during the intervention period. Although, these behaviours changed more favourably in the intervention group, these between-group-differences were not statistically significant.

Conclusions

The multifaceted computer-tailored programme for recent retirees did not appear to be effective. Apparently the transition to occupational retirement and/or participation in the study had a greater impact than the intervention programme.

Trial registration

Clinical Trials NCT00122213.

Behavioral and cognitive effects of a worksite-based weight gain prevention program: the NHF-NRG in balance-project

OBJECTIVE

Examine the effectiveness of the worksite-based weight gain prevention program Netherlands Heart Foundation-Netherlands Research program weight Gain prevention In Balance, with regard to behavioral changes and corresponding cognitive determinants.

METHODS

A nonrandomized pretest-repeated posttest control group design was applied in 12 worksites. Intervention groups received individual and environmental interventions, directed at physical activity and food intake. Measurements were executed at baseline and after 12 and 24 months.

RESULTS

Nearly all behaviors in the intervention group improved more than in the control group, even though improvements in behaviors were often too small to reach statistical significance. No positive intervention effects were observed for the cognitive factors.

CONCLUSION

Differential changes between the intervention and control group were observed for several important dietary and physical activity behaviors. Valuable information is gained regarding the implementation of weight gain prevention programs in worksites.

Design of the Balance@Work project: systematic development, evaluation and implementation of an occupational health guideline aimed at the prevention of weight gain among employees

Background

Occupational health professionals may play an important role in preventive health promotion activities for employees. However, due to a lack of knowledge and evidence- and practice based methods and strategies, interventions are hardly being implemented by occupational physicians to date. The aim of the Balance@Work project is to develop, evaluate, and implement an occupational health guideline aimed at the prevention of weight gain among employees.

Methods

Following the guideline development protocol of the Netherlands Society of Occupational Medicine and the Intervention Mapping protocol, the guideline was developed based on literature, interviews with relevant stakeholders, and consensus among an expert group. The guideline consists of an individual and an environmental component. The individual component includes recommendations for occupational physicians on how to promote physical activity and healthy dietary behavior based on principles of motivational interviewing. The environmental component contains an obesogenic environment assessment tool. The guideline is evaluated in a randomised controlled trial among 20 occupational physicians. Occupational physicians in the intervention group apply the guideline to eligible workers during 6 months. Occupational physicians in the control group provide care as usual. Measurements take place at baseline and 6, 12, and 18 months thereafter. Primary outcome measures include waist circumference, daily physical activity and dietary behavior. Secondary outcome measures include sedentary behavior, determinants of behavior change, body weight and body mass index, cardiovascular disease risk profile, and quality of life. Additionally, productivity, absenteeism, and cost-effectiveness are assessed.

Discussion

Improving workers' daily physical activity and dietary behavior may prevent weight gain and subsequently improve workers' health, increase productivity, and reduce absenteeism. After an effect- and process evaluation the guideline will be adjusted and, after authorisation, published. Together with several implementation aids, the published guideline will be disseminated broadly by the Netherlands Society of Occupational Medicine.

Trial Registration

ISRCTN73545254/NTR1190

Tracking of fruit and vegetable consumption from adolescence into adulthood and its longitudinal association with overweight

The objective of the present study was to assess to what extent fruit and vegetable intakes track over a 24-year time period and to assess longitudinal associations between fruit and vegetable intakes and (change in) BMI and sum of skinfolds. Dietary intake and anthropometrics were repeatedly assessed for 168 men and women between the ages of 12 and 36 years. Linear general estimating equations analyses were applied (1) to estimate tracking coefficients, (2) to estimate predictability for meeting the national recommendation for fruit and vegetable intake and for being in the highest quartile for fruit and vegetable intake, and (3) to estimate the association between fruit and vegetable intake and BMI and sum of skinfolds. We found that tracking coefficients were 0·33 (P < 0·001) for fruit intake and 0·27 (P < 0·001) for vegetable intake. Mean fruit intake decreased over a 24-year period. For fruit intake, predictability was higher in men than in women (OR 6·02 (P < 0·001) and 2·33 (P = 0·001) for meeting the recommendation for men and women respectively). After adjustment, fruit intake was not associated with BMI, but being in the lowest quartile of fruit intake was significantly associated with a lower sum of skinfolds. Women in the lowest quartiles of vegetable intake had significantly higher BMI and sum of skinfolds and also greater positive changes in these parameters. In conclusion, tracking and predictability for fruit and vegetable intake appear to be low to moderate, which might indicate that fruit and vegetable promotion should be started at an early age and continued into adulthood. Despite the fact that we only observed beneficial weight-maintaining effects of vegetable intake in women, promoting vegetables is important for both sexes because of other positive properties of vegetables. No evidence was found for promoting fruit intake as a means of weight maintenance.

The NHF-NRG In Balance-project: the application of Intervention Mapping in the development, implementation and evaluation of weight gain prevention at the worksite

Very few examples of theory-driven and systematically developed weight gain prevention interventions for adults have been described in the literature. The present paper systematically describes the development, implementation and evaluation framework of a weight gain prevention programme directed at young adults at the worksite, namely the NHF-NRG In Balance-project. It not only can be used as a guide to systematically develop weight gain prevention interventions, but also gives an overview of the current theoretical and empirical knowledge-base in the field of obesity prevention. The outline of the paper follows the Intervention Mapping protocol, which includes a systematic inventory of important health issues, their risk behaviours and determinants of these risk behaviours, and specification of the proximal objectives of the programme directed at both energy intake and energy expenditure. The objectives are translated into behaviour change methods and strategies, which are combined in a stepwise intervention programme, and used for a detailed evaluation plan (process and effect evaluation). The NHF-NRG In Balance-project combines mass media and individually tailored communications with worksite environmental changes to raise awareness, to motivate and to enable energy balance behaviour changes. A quasi-experimental pre-test-multiple post-test control group design was applied in 12 worksites (>500 employees).

Design of the Dutch Obesity Intervention in Teenagers (NRG-DOiT): systematic development, implementation and evaluation of a school-based intervention aimed at the prevention of excessive weight gain in adolescents

Background

Only limited data are available on the development, implementation, and evaluation processes of weight gain prevention programs in adolescents. To be able to learn from successes and failures of such interventions, integral written and published reports are needed.

Methods

Applying the Intervention Mapping (IM) protocol, this paper describes the development, implementation, and evaluation of the Dutch Obesity Intervention in Teenagers (DOiT), a school-based intervention program aimed at the prevention of excessive weight gain.

The intervention focussed on the following health behaviours: (1) reduction of the consumption of sugar-sweetened beverages, (2) reduction of energy intake derived from snacks, (3) decrease of levels of sedentary behaviour, and (4) increase of levels of physical activity (i.e. active transport behaviour and sports participation).

The intervention program consisted of an individual classroom-based component (i.e. an educational program, covering 11 lessons of both biology and physical education classes), and an environmental component (i.e. encouraging and supporting changes at the school canteens, as well as offering additional physical education classes).

We evaluated the effectiveness of the intervention program using a randomised controlled trial design. We assessed the effects of the intervention on body composition (primary outcome measure), as well as on behaviour, behavioural determinants, and aerobic fitness (secondary outcome measures). Furthermore, we conducted a process evaluation.

Discussion

The development of the DOiT-intervention resulted in a comprehensive school-based weight gain prevention program, tailored to the needs of Dutch adolescents from low socio-economic background.

Study protocol of a cluster randomised controlled trial investigating the effectiveness of a tailored energy balance programme for recent retirees

BACKGROUND

People in transitional life stages, such as occupational retirement, are likely to gain weight and accumulate abdominal fat mass caused by changes in physical activity and diet. Hence, retirees are an important target group for weight gain prevention programmes, as described in the present paper.

METHODS/DESIGN

A systematic and stepwise approach (Intervention Mapping) is used to develop a low-intensity energy balance intervention programme for recent retirees. This one-year, low-intensity multifaceted programme aims to prevent accumulation of abdominal fat mass and general weight gain by increasing awareness of energy balance and influencing related behaviours of participants' preference. These behaviours are physical activity, fibre intake, portion size and fat consumption. The effectiveness of the intervention programme is tested in a cluster randomised controlled trial. Measurements of anthropometry, physical activity, energy intake, and related psychosocial determinants are performed at baseline and repeated at 6 months for intermediate effect, at 12 months to evaluate short-term intervention effects and at 24 months to test the sustainability of the effects.

DISCUSSION

This intervention programme is unique in its focus on retirees and energy balance. It aims at increasing awareness and takes into account personal preferences of the users by offering several options for behaviour change. Moreover, the intervention programme is evaluated at short-term and long-term and includes consecutive outcome measures (determinants, behaviour and body composition).

Modeling individual and physical environmental factors with adolescent physical activity

BACKGROUND

Recent calls have been made to consider both environmental factors and individual-level factors in the explanation of physical activity (PA). The present study tested a conceptual model that integrated past PA, relevant environmental-level and individual-level factors and their associations with adolescent PA, using the tenets of the Theory of Planned Behavior (TPB).

METHODS

Data were gathered in an adolescent sample (n=221; 60% girls) using questionnaires. PA was assessed in May 2003 and November 2003. Theory of Planned Behavior cognitions regarding PA and the environmental factors under study were assessed in November 2003. Confirmatory factor analyses and path analyses were performed using AMOS software.

RESULTS

The initial structural model did not provide an acceptable fit to the data. Including a direct path from past PA to current PA significantly improved model fit to an acceptable fit. Including a direct path from past PA to environmental perceptions did not significantly improve model fit. Including a direct path from the environmental variables to current PA did not significantly improve model fit. Current PA was most strongly influenced by past PA, while environmental aesthetics and distance to PA opportunities were indirectly related to adolescents' intention to be physically active. Significant standardized path coefficients ranged from 0.14 to 0.34 and explained 17% variance in current PA.

CONCLUSIONS

Combining past PA, Theory of Planned Behavior cognitions, and environmental factors increased our understanding of their relative influences on adolescent PA. Implications for future research on physical activity are discussed.

Environmental influences on energy balance-related behaviors: a dual-process view

Background

Studies on the impact of the 'obesogenic' environment have often used non-theoretical approaches. In this journal's debate and in other papers authors have argued the necessity of formulating conceptual models for differentiating the causal role of environmental influences on behavior.

Discussion

The present paper aims to contribute to the debate by presenting a dual-process view on the environment – behavior relationship. This view is conceptualized in the EnRG framework (Environmental Research framework for weight Gain prevention). In the framework, behavior is postulated to be the result of a simultaneous influence of conscious and unconscious processes. Environmental influences are hypothesized to influence behavior both indirectly and directly. The indirect causal mechanism reflects the mediating role of behavior-specific cognitions in the influence of the environment on behavior. A direct influence reflects the automatic, unconscious, influence of the environment on behavior. Specific personal and behavioral factors are postulated to moderate the causal path (i.e., inducing either the automatic or the cognitively mediated environment – behavior relation). In addition, the EnRG framework applies an energy balance-approach, stimulating the integrated study of determinants of diet and physical activity.

Conclusion

The application of a dual-process view may guide research towards causal mechanisms linking specific environmental features with energy balance-related behaviors in distinct populations. The present paper is hoped to contribute to the evolution of a paradigm that may help to disentangle the role of 'obesogenic' environmental factors.

Participation rates in worksite-based intervention studies: health promotion context as a crucial quality criterion

Recently, a set of specific quality evaluation criteria for health promotion research has been proposed in this journal. One of the quality criteria identified is the 'health promotion context'. With this paper we would like to contribute to the dialogue by specifying the importance of this criterion on the basis of our on experience with worksite-based obesity prevention interventions. We advocate the reporting of participation rates among approached worksites in publications on worksite intervention effects. Such information will help to draw conclusions on the practical relevance of the shown effectiveness of the intervention. Health promotion practice is advised to adopt and disseminate evidence-based interventions, accompanied by a diffusion study with a minimal research burden for participants.

Obesity prevention in low socioeconomic status urban African-American adolescents: study design and preliminary findings of the HEALTH-KIDS Study

OBJECTIVES

Obesity prevention among children and adolescents is a public health priority; however, limited school-based intervention trials targeting obesity have been conducted. This article provides an overview of the study design and baseline preliminary findings of our ongoing school-based intervention study.

DESIGN

Randomized intervention trial to test a school-based, environmental obesity prevention program in urban low socioeconomic status (SES) African-American adolescents. The intervention program was developed based on several behavioral theories and was guided by preliminary findings based on focus group discussion and baseline data.

SETTING

Four Chicago public schools in the US.

SUBJECTS

Over 450 5-7th graders and their families and schools were involved.

RESULTS

Our baseline data indicate a high prevalence of overweight (43% in boys and 41% in girls) and a number of problems in these children's physical activity and eating patterns. Only 26% reported spending > or = 20 min engaged in vigorous-moderate exercise in > or = 5 days over the past 7 days; 29% reported spending > or = 5 h each day watching TV, playing video games, or using computer. They also consumed too many fried foods and soft drinks. On average, 55% consumed fried foods > or = 2 times/day over the past 7 days; regarding soft drinks, 70% reported consuming > or = 2 times/day.

CONCLUSION

School-based obesity prevention programs are urgently needed in the target US urban, low SES, minority communities. These data can be used to inform intervention activities.