Skip over navigation

Journal Issue: Special Education for Students with Disabilities Volume 6 Number 1 Spring 1996

REVISITING THE ISSUES: The Effects of Medicaid Expansions on Insurance Coverage of Children
Lisa C. Dubay Genevieve M. Kenney

Data Sources

The Urban Institute's Transfer Income Model, Version 2 (TRIM2), a well-accepted microsimulation model of tax and transfer programs affecting individuals and families, is used for this analysis.14 The database underlying TRIM2 is the March Current Population Survey, a nationally representative sample of the U.S. population. Used for this analysis were the 1989 and 1994 versions of the March CPS, which include questions regarding income levels and health insurance coverage for each member of the household in the previous year. In the Winter 1995 issue of The Future of Children, Lewit and Baker used TRIM2 data to analyze health insurance coverage of children under age 18 over the same period.15

Three weaknesses in the CPS health insurance information deserve note. The first is that the CPS does not ask directly if a person is uninsured. Rather, estimates of the uninsured from the CPS reflect the number of persons who failed to say yes to any of the questions about specific types of health insurance. The second weakness is that, although the survey asks for coverage during the previous year,16 comparisons with other surveys indicate that some respondents are, in fact, providing information about their current insurance status.17 Third, the CPS probably underreports program participation, including participation in Medicaid, because CPS participation estimates are considerably lower than the number of participants reflected in program data. Using the TRIM2 edited version of the CPS rather than the CPS itself is important because it mitigates some of these problems by using the CPS health insurance questions to create individual indicators and by correcting for underreporting. In addition, TRIM2 identifies each Medicaid-eligible person and the person's eligibility category, even for persons who do not report Medicaid coverage.18