case based (and can include a family or group of siblings) and Medicaid data are individual based (Ellwood, 1999).
It is useful to maximize the use of common health identifiers. In some states, such as North Carolina, a common health identifying number is used across a range of data sets, from vital statistics to disease registries (North Carolina State Center for Health Statistics, 1997). Where the health identifying number and social services number can be linked together, one can evaluate a child’s experiences and outcomes with both health and social service programs.
Examining claims data under Medicaid or CHIP requires that issues of confidentiality are responsibly addressed. Many states, such as California, Maryland, Kentucky, and Tennessee, are already addressing these concerns through data sharing and data warehousing projects: (National Conference of State Legislators, 1999).
In addition to these concerns about administrative data, identification of the relevant research questions is critical in guiding the analysis plan and selection of relevant data sets. The question of whether regulations make health care services available to all children who need them could be answered with eligibility data. The question of whether children leaving TANF continue to get needed health services cannot be answered with eligibility or enrollment data. That question only can be answered with service utilization data. The question of whether children exiting TANF are continuing to get timely immunizations could be answered by Medicaid services data or by separate immunization registries within a state (Child Trends, 1999).
Another relevant research question to include would be whether the population of cases had changed since PRWORA was enacted. Will you study AFDC populations before PRWORA, or just those TANF cases after the legislation was implemented? This would require including AFDC and TANF cases in the research. Beyond analysis of the data about AFDC/TANF and Medicaid, the Food Stamps Program, or WIC, research should include questions about barriers to supplemental services for families exiting welfare. One possible barrier is the continued linking of welfare to these supplemental services, despite efforts over the past decade to delink regulations about the programs. In practice, and for individual families, these programs remain interwoven. Another barrier is the complicated eligibility rules for services to support families leaving TANF and the media about the program that might affect whether families think they are eligible or not (Ellwood, 1999). Finally, a research question of interest would be “Upon exiting TANF, do families drop supplemental services, add supplemental services, or maintain existing levels?”