We obtain Medicaid participation records from the Centers for Medicare and Medicaid Services (CMS). States submit their data to the CMS quarterly. Individuals are included in the file if Medicaid covered them for at least one day during the quarter. No personal identifiers are included on the records used by the SAHIE program.
We aggregate the data to the state and county levels by age and sex.
We use counts of participants for the month of May in the estimation process. The counts of individual participants in the Medicaid program for some counties counties are unavailable or have data values that seem implausible. In either of these cases the raw Medicaid count is not used. The rejection criterion relies on a regression-based approach. The predictors are: the population, the numbers of tax poor exemptions, and the numbers in poverty as measured by Census 2000.
We combine the Medicaid and Children's Health Insurance Program (CHIP) participation data together into one variable for use in our models.
For more information see the Medicaid page.