Abstract: We compare two different sources of enrollment counts for the Children's Health Insurance Program from 2000–2005. Although it is impossible to know which sources accurately report enrollment, we classify instances where data sources do not agree as an indication that at least one source reports enrollment inaccurately. We find that 26 states have Medicaid expansion programs and 18 states have stand-alone programs that report similar enrollment counts across the two data sources. Eight states with Medicaid expansion programs and five states with a stand-alone program have substantial inconsistencies that include missing enrollment counts or a disagreement in enrollment counts.
Keywords: Children's Health Insurance Program (CHIP), Enrollment, Statistical Enrollment Data System (SEDS), Medicaid Statistical Information System (MSIS)