Equity and economic evaluation of system-level health interventions : a case study of Brazil's Family Health Program

Distributional economic evaluation estimates the value for money of health interventions in terms of population health and health equity impacts. When applied to interventions delivered at the population- or health system-level (PSIs) instead of clinical interventions, additional practical and methodological challenges arise. Using the example of the Family Health Program (PSF) in Brazil, a community-level primary care system intervention, we seek to illustrate these challenges and provide potential solutions. We use a distributional cost-effectiveness analysis (DCEA) approach to evaluate the impact of the PSF on population health and between-state health inequalities in Brazil. Data on baseline health status, disease prevalence and PSF effectiveness are extracted from the literature and incorporated into a Markov model to estimate the long-term impacts in terms of disability-adjusted life years. The inequality and average health impacts are analysed simultaneously using health-related social welfare functions. Uncertainty is computed using Monte Carlo simulation. The DCEA encountered several challenges in the context of PSIs. Non-randomised, quasi-experimental methods may not be powered to identify treatment effect heterogeneity estimates to inform a decision model. PSIs are more likely to be funded from multiple public sector budgets, complicating the calculation of health opportunity costs. We estimate a cost-per-DALY of funding the PSF of $2,640. Net benefits were positive across the likely range of intervention cost. Social welfare analysis indicates that, compared to gains in average health, changes in health inequalities accounted for a small proportion of the total welfare improvement, even at high levels of social inequality aversion. Evidence on the population health and health equity impacts of PSIs can be incorporated into economic evaluation methods, although with additional complexity and assumptions. The case study results indicate that the PSF is likely to be cost-effective, but that the inequality impacts are small and highly uncertain.