Shape Up Somerville's return on investment: Multi-group exposure generates net-benefits in a child obesity intervention.

Community-based interventions may reduce and prevent childhood obesity by transforming the environments in which children live, learn, and play through a series of interventions implemented throughout the community that encourage healthy behaviors. While empirical support is building for the effectiveness of such interventions, little is known about the economic costs and benefits of community-wide childhood obesity interventions. This study examined whether the benefits of a community-wide, child-focused, obesity prevention intervention, Shape Up Somerville: Eat Smart Play Hard (SUS), exceeded its costs by estimating its return on investment. The SUS intervention study occurred in Somerville, Massachusetts (and in two additional geographic areas, which were the study's control group) during the 2003/04 and 2004/05 school years. We estimated SUS's costs using SUS data over the two-year intervention. We estimated benefits (i.e., healthcare costs and productivity losses averted for children and their parents) over a ten-year time horizon using SUS effectiveness results and other sources. SUS generated an estimated $1.51 in savings for every $1.00 invested in the program (return on investment of $0.51). Over ten years, the estimated costs averted were over $500,000 with net benefits of $197,120 (2014 dollars). SUS was estimated to be a cost-saving intervention when examined over a ten-year time horizon. The excess benefits generated by SUS likely arose from the community-wide nature of the intervention which extended exposure (and estimated benefits) beyond children to parents as well. These results illustrate that allocating resources to community-wide, child-focused obesity prevention interventions may be a beneficial investment.