Collaborative system modeling to develop childhood obesity prevention policies: An innovative approach to working with legislators

This project's objective was to provide policymakers with a systemic perspective on childhood obesity and to enable more rigorous discussions of policy alternatives. A diverse team developed a simple system dynamics model of childhood obesity for legislators. The team included state legislators, legislative staff, and experts in nutrition, exercise physiology, epidemiology, pediatric medicine, and system dynamics. A simple user interface enabled policymakers to explore policy interventions in terms of their impact on obesity and associated health care costs over the coming decade. Participants were encouraged to predict outcomes, articulate theories and inquire into any differences between their expectations and the model's outcomes. There is no “magic bullet” for reducing childhood obesity, but model results suggested that coherent policy combinations hold promise, provided that they are implemented intensively and sustained over time. Time lags were observed for all interventions, but significant reductions could be seen within 5 years by maximizing a coherent set of policies, particularly those affecting the school environment. Some policy combinations lowered the prevalence of obese children to 10%, effectively returning prevalence to 1970 rates. Using a collaborative system modeling process and a systemic perspective, this project brought together legislators and content experts to develop a set of actionable policy options. The resulting model provides a framework, a common language and a credible and engaging tool that has already begun enabling state legislators to engage in more rigorous discussions about effective and feasible policy options for reducing childhood obesity. The approach shows promise for other complex policy issues.