Medicaid enrollment levels need to be accurately measured in order to track reform progress of the Patient Protection and Affordable Care Act. In surveys, for example, sometimes Medicaid enrollees are counted as uninsured, when in fact they have public insurance rather than lacking insurance altogether.
These investigators looked at existing research of the accuracy of respondent reports on public insurance, which includes Medicaid and State Children’s Health Insurance Plan.
They found studies were one of two designs. Experimental studies conducted in conjunction with statewide general population studies use administrative data and then send a survey to a sample and match how respondents report their coverage compared to the known administrative data (accuracy 74–89%). Matching studies take information from an existing survey and compare it to corresponding administrative data (accuracy 57–82%).
“Knowing the strengths and weaknesses of the various sources of survey estimates, why they differ, and how they can be improved is important so that they can be appropriately used in health policy research,” the authors conclude.