Davene Wright
*Harvard PhD Program in Health Policy Alumna & Faculty Member
Dissertation Title: "Examining Methods Used to Evaluate the Cost-Effectiveness of Childhood Obesity Interventions"This dissertation examines methods used to evaluate the costs and effectiveness of childhood obesity interventions in order to help decision-makers prioritize among competing health programs using standardized outcomes.
Chapter 1 generates inputs for use in cost-effectiveness analyses of childhood obesity interventions. In Chapter 1.1, I use data from the Medical Expenditure Panel Survey to predict the expenditures associated with obesity in childhood and adolescence. I found that obese children and adolescents have significantly different expenditures than their normal weight counterparts. I conclude that exclusion of obesity-related medical expenditures can potentially undervalue the cost-effectiveness of interventions. In Chapter 1.2, I use data from the NICHD Study of Early Child Care and Youth Development to examine the longitudinal trajectory of child weight. I derived probabilities of transitioning between weight classes that can be used in conjunction with a decision-analytic model to extrapolate the effectiveness of childhood obesity interventions beyond childhood. I found that we need to deviate from standard CDC categories of weight classes in order to accurately capture the risk of future obesity.
In Chapter 2, I evaluate the cost-effectiveness of a primary care-based obesity prevention program, High Five for Kids. Over two years, High Five for Kids was low-cost, but only marginally effective in reducing BMI. I used a decision analytic simulation model to extrapolate trial outcomes over a 10-year horizon, and found that in the long-term, primary care based obesity prevention was likely to be cost-effective relative to usual care. I also found that key methodological considerations can meaningfully influence the perceived cost-effectiveness of childhood obesity interventions.
In Chapter 3, I develop an agent-based model that can capture the dynamics of the spread of obesity within families under a theoretical intervention. I found that the concept of the “contagion” of obesity could result in significant collateral weight loss in family members not targeted in an intervention. As a result, cost-effectiveness analyses may underestimate the benefits of obesity interventions. Moreover, I found that unless interventions are targeted toward all obese children in a family, the contagion of obesity can hinder weight loss in intervention targets. This model can be leveraged as a useful tool to identify effective family-based obesity intervention strategies and inform randomized controlled obesity prevention trials.