A New Model for Evaluation of Interventions to Prevent Obesity in Early Childhood

Abstract

Background: Childhood obesity is a serious public health issue. In Australia, 1 in 4 children is already affected by overweight or obesity at the time of school entry. Governments around the world have recognized this problem through investment in the prevention of pediatric obesity, yet few interventions in early childhood have been subjected to economic evaluation. Information on cost-effectiveness is vital to decisions about program implementation. A challenge in evaluating preventive interventions in early childhood is to capture long-term costs and outcomes beyond the duration of an intervention, as the benefits of early obesity prevention will not be realized until some years into the future. However, decisions need to be made in the present, and modeling is one way to inform such decisions. Objective: To describe the conceptual structure of a new health economic model (the Early Prevention of Obesity in CHildhood (EPOCH) model) for evaluating childhood obesity interventions; and to validate the epidemiologic predictions. Methods and Results: We use an individual–level (micro-simulation) method to model BMI trajectories and the progression of obesity from early childhood to adolescence. The equations predicting individual BMI change underpinning our model were derived from data from the population-representative study, the Longitudinal Study of Australian Children (LSAC). Our approach is novel because it will account for costs and benefits accrued throughout childhood and adolescence. As a first step to validate the epidemiological predictions of the model, we used input data representing over 250,000 children aged 4/5 years, and simulated BMI and obesity trajectories until adolescence. Simulated mean BMI and obesity prevalence for boys and girls were verified by nationally-representative data on children at 14/15 years of age. Discussion: The EPOCH model is epidemiologically sound in its prediction of both BMI trajectories and prevalence of obesity for boys and girls. Future developments of the model will include socio-economic position and will incorporate the impacts of obesity on healthcare costs. The EPOCH model will help answer: when is it best to intervene in childhood; what are the most cost-effective approaches and which population groups will benefit most from interventions.

The effectiveness of health professional‐delivered interventions during the first 1000 days to prevent overweight/obesity in children: A systematic review

“…Previous reviews have also noted the lack of assessment of the cost‐effectiveness of interventions . Other authors have also noted the lack of economic evaluations of childhood obesity interventions, particularly in the early years; this is changing however . In the current climate of expenditure cuts to health services, it is difficult for health professionals to protect time to deliver such interventions.…”

Methods for the economic evaluation of obesity prevention dietary interventions in children: A systematic review and critical appraisal of the evidence

“…Failing to include childhood health outcomes risks underestimating the economic benefits of early intervention and increases levels of uncertainty when longer time horizons are considered. Moreover, some decision makers are interested in early outcomes in their own right 82 . One solution is to present economic outcomes over a selected range of time horizons up to death, allowing the impact on uncertainty to be explicitly communicated 59,82 .…”

Cost‐Effectiveness of a Novel Sleep Intervention in Infancy to Prevent Overweight in Childhood

“…A strength of our study is that the economic evaluation is based on data from an RCT and that the resources used to deliver the intervention were derived from trial records. The EPOCH microsimulation model, used to predict BMI trajectories, is based on a large Australian longitudinal cohort and it has been internally validated to age 15 years (25), thus providing confidence in the prediction of future BMI. We used best practice methods for economic evaluation (35); utilities for different weight status groups were derived from a systematic review and meta‐analysis (26), and direct health care costs were derived from national‐level Australian data (31,32).…”

“…The secondary outcome was BMI at 5 and 15 years. We used the recently developed Early Prevention of Obesity in Childhood (EPOCH) health economic model to estimate cost‐effectiveness (25). This is a deterministic microsimulation model that predicts individual‐level child BMI trajectories and associated QALYs and health care costs throughout childhood and adolescence.…”

“…Health care costs of participants to age 15 years were modeled using the health care cost submodel of the EPOCH model (25), which predicts health care costs using a “top down” method that incorporates administrative records of hospital, doctor, and medicine costs by age (31,32). It then applies percentage excess costs for those with overweight and obesity relative to healthy weight, derived from a large study of Australian children (8).…”