Utility values for childhood obesity interventions: a systematic review and meta-analysis of the evidence for use in economic evaluation.

Rigorous estimates of preference-based utilities are important inputs into economic evaluations of childhood obesity interventions, yet no published review currently exists examining utility by weight status in paediatric populations. A comprehensive systematic literature review and meta-analysis was therefore undertaken, pooling data on preference-based health state utilities by weight status in children using a random-effects model. Tests for heterogeneity were performed, and publication bias was assessed. Of 3,434 potentially relevant studies identified, 11 met our eligibility criteria. Estimates of Cohen's d statistic suggested a small effect of weight status on preference-based utilities. Mean utility values were estimated as 0.85 (95% uncertainty interval [UI] 0.84-0.87), 0.83 (95% UI 0.81-0.85), 0.82 (95% UI 0.79-0.84) and 0.83 (95% UI 0.80-0.86) for healthy weight, overweight, obese and overweight/obese states, respectively. Meta-analysis of studies reporting utility values for both healthy weight and overweight/obese participants found a statistically significant weighted mean difference (0.015, 95% UI 0.003-0.026). A small but statistically significant difference was also estimated between healthy weight and overweight participants (0.011, 95% UI 0.004-0.018). Study findings suggest that paediatric-specific benefits of obesity interventions may not be well reflected by available utility measures, potentially underestimating cost-effectiveness if weight loss in childhood/adolescence improves health or well-being.