Presentation (CTI)

OBJECTIVES: Childhood obesity is a significant global health challenge affecting over 379 million children, disproportionately concentrated in disadvantaged urban communities. Community-based prevention initiatives, often co-designed with local stakeholders, introduce localised heterogeneity and short-term results, creating evidence transferability challenges. We present an operational framework developed within the Cities for Better Health Childhood Obesity Prevention Initiative (CBH COPI), a multi-country programme co-designing, implementing, and evaluating community-based dietary and physical activity interventions spanning six global cities. While experimental studies capture immediate behavioural shifts, this global modelling framework translates short-term changes into long-term health and economic outcomes critical for justifying sustained investment in primary prevention.
METHODS: CBH COPI delivers multi-level, multi-component interventions targeting children aged 6-13 years. Employing a controlled repeated cross-sectional analysis, with a minimum of 12,000 data points across baseline, 12- and 24-month intervals, the framework establishes a two-stage data-to-model pipeline: (1) collection of localised shifts in BMI z-scores, diet, physical activity, and health-related quality of life (HRQoL); and (2) translation of these outcomes into a localised adaptation of the PRIMEtime multistate life table model to estimate long-term impacts on Quality-Adjusted Life Years, obesity-related disease incidence, and cost-effectiveness.
RESULTS: This scalable methodology harmonises heterogeneous intervention effects into a common health economic modelling platform. Importantly, it aims to reduce decision uncertainty by highlighting the long-term, compounding impacts of short-term actions. This approach facilitates a standardised assessment of effectiveness and cost-effectiveness, enabling scalability across diverse healthcare systems.
CONCLUSIONS: This framework demonstrates an approach to bridging heterogeneity in community-based prevention initiatives. While CBH COPI serves as the proof-of-concept, the framework’s architecture is widely applicable to other public health contexts. By modelling long-term HRQoL and economic outputs, it addresses key challenges in evidence comparability for complex public health programmes, empowering decision-makers to assess the wider, long-term societal value of investing in prevention strategies to improve health equity and cardiometabolic health.