MEDICAID UNDERREPORTING IN THE CPS RESULTS FROM A RECORD CHECK STUDY

The use of survey data can be significantly hampered by the occurrence of measurement error, particularly that engendered by respondent misreporting. Previous studies have shown that public program participation tends to be substantially misreported and underestimated. Comparison with administrative records shows such a situation with the reporting of Medicaid enrollment in the U. S. Census Bureau's Current Population Survey (CPS); for 36.2 percent of enrollees, their coverage was not reported in the survey. While false positive reporting also occurs, it is, on a percentage basis, much less frequent. To understand and correct for the false negative reporting, and to develop improvements to surveys to mitigate the occurrence of misreporting, it is useful to understand the factors that relate to it. This research sought to establish the relationship between false negative Medicaid reporting and various factors associated with the coverage ( such as recency and intensity), the enrollee ( such as demographics and the use of services), and differences in coverage status between the respondent and the person for whom he or she was reporting. Results show that coverage patterns including shared coverage, recency, and intensity of coverage all strongly relate to false negative Medicaid reporting in the CPS. The findings provide important guidance for questionnaire design improvements as well as model-based adjustments to the survey data.