An interrupted time series analysis of state-level incremental supplements to the Earned Income Tax Credit (EITC) program was performed using data from 1993 to 2010 Behavioral Risk Factor Surveillance System surveys and state-level life expectancy. The cost effectiveness of state EITC supplements was estimated using a microsimulation model, which was run in 2015.
Supplemental EITC programs increased health-related quality of life and longevity among the poor. The program costs about $7,786/quality-adjusted life-year gained (95% CI=$4,100, $13,400) for the average recipient. This ratio increases with larger family sizes, costing roughly $14,261 (95% CI=$8,735, $19,716) for a family of three.
State supplements to EITC appear to be highly cost effective, but randomized trials are needed to confirm these findings.