Working Paper: NBER ID: w8514
Authors: David Card; Andrew K. G. Hildreth; Lara D. Shores-Heppard
Abstract: This paper studies the accuracy of reported Medicaid coverage in the Survey of Income and Program Participation (SIPP) using a unique data set formed by matching SIPP survey responses to administrative records from the State of California. Overall, we estimate that the SIPP underestimates Medicaid coverage in the California population by about 10 percent. Among SIPP respondents who can be matched to administrative records, we estimate that the probability someone reports Medicaid coverage in a month when they are actually covered is around 85 percent. The corresponding probability for low-income children is even higher - at least 90 percent. These estimates suggest that the SIPP provides reasonably accurate coverage reports for those who are actually in the Medicaid system. On the other hand, our estimate of the false positive rate (the rate of reported coverage for those who are not covered in the administrative records) is relatively high: 2.5 percent for the sample as a whole, and up to 20 percent for poor children. Some of this is due to errors in the recording of Social Security numbers in the administrative system, rather than to problems in the SIPP.
Keywords: Medicaid; SIPP; health insurance; low-income families; California
JEL Codes: I38; C81
Edges that are evidenced by causal inference methods are in orange, and the rest are in light blue.
| Cause | Effect |
|---|---|
| SIPP reported Medicaid coverage (I18) | actual Medicaid coverage (I18) |
| actual Medicaid coverage (I18) | SIPP reported Medicaid coverage (I18) |
| actual Medicaid coverage for low-income children (I13) | SIPP reported Medicaid coverage for low-income children (I18) |
| SIPP reported Medicaid coverage (I18) | actual Medicaid coverage (false positive) (I18) |
| SIPP reported Medicaid coverage for poor children (I18) | actual Medicaid coverage (false positive for poor children) (I18) |
| errors in administrative data (C83) | misreporting of Medicaid coverage (I18) |