The new announcement that the Census Bureau is completely changing its Current Population Survey (CPS) questions about health insurance coverage (see previous post here) is devastating for those of us who do health research.
We have all known for years — decades — that the CPS count of the insured isn’t especially accurate. The questions it asks are about full-year coverage but people tend to answer based on their current status. It chronically under-reports Medicaid enrollment — the actual head count from Medicaid programs is always higher than indicated in the survey. The same is probably true for employment-based coverage. It has often been criticized for being weak on foreign language questions. Massachusetts, for example, has a significant population of people who speak Portuguese and that state thought the CPS failed to capture those people.
The Census Bureau recently (in 2007) revised its numbers because the software was misallocating people who reported that everyone in their family was covered. More on this below.