Objectives. To analyze the impact of public health insurance expansions and the use of enrollee cost sharing on insurance status and receipt of clinically indicated preventive screenings and physician services.
Data Source. This study uses Behavioral Risk Factor Surveillance System (BRFSS) data from 1997 to 2007.
Study Design. This study uses multivariate difference-in-difference logistic regression modeling of pooled cross-sectional time series data. The effect of the expansions on insurance status and access to care is identified by cross-state variation in program implementation, as well as cross-state and within-state variation in program eligibility criteria over time.
Principal Findings. Childless adult expansions, regardless of cost-sharing levels, reduced uninsurance rates and decreased the likelihood that childless adults needed to see a physician but did not because of cost. Expansions with traditional public insurance cost-sharing requirements increased the use of preventive screenings, while expansions with increased cost-sharing requirements did not.
Conclusions. Cost-sharing requirements did not have an impact on the ability to see a physician when needed, but they played an important role in the utilization of preventive services. Expanding public health insurance to low-income, childless adults presents a promising policy opportunity, but there are trade-offs between the efficiencies obtained through increased cost sharing and the potential inefficiencies due to the lower use of preventive services.