The Pacific OPIC project (Obesity Prevention in Communities) - objectives and designs

Background: Evidence on how to reduce the increasing prevalence of youth obesity is urgently needed in many countries.The Pacific OPIC Project (Obesity Prevention In Communities) is a series of linked studies in four countries (Fiji, Tonga, New Zealand, Australia) which is designed to address this important problem.
Objectives: The studies aim to: 1) determine the overall impact of comprehensive, community-based intervention programs on overweight/obesity prevalence in youth; 2) assess the feasibility of the specific intervention components and their impacts on eating and physical activity patterns; 3) understand the socio-cultural factors that promote obesity and how they can be infl uenced; 4) identify the effects of food-related policies in Fiji and Tonga and how they might be changed; 5) estimate the overall burden of childhood obesity (including loss of quality of life); 6) estimate the costs (and cost-effectiveness) of the intervention programs, and; 7) increase the capacity for obesity prevention research and action in Pacific populations.
Design: The community studies use quasi-experimental designs with impact and outcome assessments being measured in over 14,000 youth across the intervention and control communities in the four sites. The multi-strategy, multi-setting interventions will run for 3 years before fi nal follow up data are collected in 2008. The interventions are being informed by socio-cultural studies that will determine the family and societal infl uences on food intake, physical activity and body size perception.
Progress and conclusions: Baseline studies have been completed and interventions are underway. Despite the many challenges in implementing and evaluating community-based interventions, especially in the Pacifi c, the OPIC Project will provide rich evidence about what works and what does not work for obesity prevention in youth from European and Pacific backgrounds.

ACE-Obesity : priority setting for obesity prevention

The ACE-Obesity study uses an evidence-based approach to evaluate interventions aimed at reducing the prevalence of obesity in Australian youth. It informs decision-makers about the benefits of individual interventions and the packaging of a coherent strategy for obesity prevention and management. To avoid methodological confounding, the approach employs standardised methods including a two stage concept of benefit; a common comparator, setting and decision context; Australian data; and extensive probabilistic uncertainty testing. The technical cost-effectiveness results (cost per DALY) for each of the selected interventions will be reported. Modelling is undertaken to convert changes in behaviour to BMI outcomes and then to DALYs, and issues of the attribution of costs across multiple objectives arise. Due process is achieved by involving stakeholders on a Working Group, and by consideration of second stage filters (such as equity, acceptability and feasibility). The results are brought together in a 'league table' in which all the interventions are ranked in order of economic merit without the usual methodological concerns about results drawn from studies lacking in comparability. In packaging interventions to meet particular budget allocations, the divisibility, mutual exclusivity and returns to scale of individual interventions are considered, as well as issues of program logic, target group coverage and a range of settings.

Selection of priority groups for obesity prevention current approaches and development of an evidence-informed framework

Resources for obesity prevention interventions are inevitably limited, necessitating the selection of priority groups to ensure effective and equitable use of funds. This paper aims to review published approaches to selection of priority groups ('target populations') for obesity prevention, and to present the development of a new systematic framework for organizing and assessing evidence for selecting priority groups. A review was conducted of the process and justification described for selecting priority groups in a sample of obesity prevention publications. Using the results of this review and adaptation of theory and frameworks in both the obesity prevention and health promotion priority-setting literature, a framework was developed for assessment of potential priority groups for obesity prevention. The published literature lacks discussion of and explicit processes for selection of priority groups for obesity prevention intervention. The new framework describes specific types of evidence that should be considered in the assessment of a potential priority group for obesity prevention and has applications for funding and implementing community-based or settings-level obesity prevention interventions and research. Application of this framework has the potential to enhance the effective use of limited obesity prevention resources and to identify areas in need of additional research evidence.

Scaling up community-based obesity prevention in Australia : background and evaluation design of the health promoting communities : being active eating well initiative

Background : There is only limited evidence available on how best to prevent childhood obesity and community-based interventions hold promise, as several successful interventions have now been published. The Victorian Government has recently funded six disadvantaged communities across Victoria, Australia for three years to promote healthy eating and physical activity for children, families, and adults in a community-based participatory manner. Five of these intervention communities are situated in Primary Care Partnerships and are the subject of this paper. The interventions will comprise a mixture of capacity-building, environmental, and whole-of-community approaches with targeted and population-level interventions. The specific intervention activities will be determined locally within each community through stakeholder and community consultation. Implementation of the interventions will occur through funded positions in primary care and local government. This paper describes the design of the evaluation of the five primary care partnership-based initiatives in the 'Go for your life' Health Promoting Communities: Being Active Eating Well (HPC:BAEW) initiative.

Methods/Design : A mixed method and multi-level evaluation of the HPC:BAEW initiative will capture process, impact and outcome data and involve both local and state-wide evaluators. There will be a combined analysis across the five community intervention projects with outcomes compared to a comparison group using a cross-sectional, quasi-experimental design. The evaluation will capture process, weight status, socio-demographic, obesity-related behavioral and environmental data in intervention and comparison areas. This will be achieved using document analysis, paper-based questionnaires, interviews and direct measures of weight, height and waist circumference from participants (children, adolescents and adults).

Discussion : This study will add significant evidence on how to prevent obesity at a population level in disadvantaged and ethnically diverse communities. The outcomes will have direct influence on policy and practice and guide the development and implementation of future obesity prevention efforts in Australia and internationally.