The Effects of Partial-Year Insurance Coverage on the Healthcare Utilization of Low-Income Children
- Presenter:
Chair: TBA; Discussant: TBA Mon June 5, 2006 13:45-15:15 Room 313
Title: The Effects of Partial-Year Insurance Coverage on the Healthcare Utilization of Low-Income Children
Rationale: Studies on the dynamics of the insurance coverage of children demonstrate that treating insurance as a static measure provides an incomplete representation of the coverage of low-income children. Insurance coverage for this group is especially dynamic throughout the course of a year, with more children spending part of the year uninsured than spending the full year uninsured. The vast majority of research on the effects of insurance coverage on children’s access to care estimates the effects of point-in-time insurance coverage on access and utilization outcomes. With few exceptions, existing research does not examine the relationship between the amount of the year spent with insurance coverage and children’s healthcare utilization.
Objective: This work examines the effects of partial-year insurance coverage on the healthcare utilization of low-income children, accounting for the endogeneity of insurance status.
Data and Methods: The relationship seen in observational studies between health insurance and healthcare utilization is biased by unobservable characteristics that affect both insurance status and healthcare usage. Existing work on the effects of partial-year coverage on utilization measures is observational and does not account for unobserved heterogeneity among insured and uninsured children. This study uses instrumental variable techniques appropriate for limited dependent variables to provide evidence regarding the causal impacts of partial-year insurance coverage on the healthcare utilization of children.
We employ various instruments seen in the existing literature as well as additional instruments suggested by theory to estimate the insurance-utilization relationship for children. Several previous studies have utilized the variation in eligibility across states and years as an instrument with which to identify the relationship of interest. In addition to using this measure, we also use family-level and state-level instruments to estimate the effects of partial-year coverage on utilization measures.
The dependent variables of interest are the number of doctor visits received in the past year, whether a child has a usual source of care, whether a child was admitted into the hospital in the past year, and whether the child visited the emergency room in the past year. A sample of approximately 35,000 low-income children drawn from the 1997, 1999 and 2002 waves of the National Survey of America’s Families (NSAF) is used for the analysis.
Preliminary Results: Children with partial-year coverage have lower rates of healthcare utilization than those with full-year coverage but use more care than children who spend the entire year uninsured. The effect of the number of months of coverage on utilization exhibits a dose-response relationship, with each additional month of coverage lowering the probability of using care. Estimates from instrumental variables specifications are larger than those of ordinary least squares specifications.
Conclusions: This paper provides new evidence on the relationship between partial-year insurance status and the healthcare utilization of children. Its hope is to contribute to the currently small literature on this topic through employing a quasi-experimental design that accounts for non-random selection into insurance status.
