Background. In 2015, two versions of the Current Population Survey Annual Social and Economic Supplement (CPS ASEC) were fielded. One survey included the traditional health insurance questions (asked prior to 2014) and the other included the redesigned questions (asked in 2014 and beyond).

Objective. To estimate the effect of changing the health insurance questions on the uninsured rate.

Data and Methods. We use the 2015 CPS ASEC and 2015 Parallel Survey, both of which ask about health insurance coverage in 2014.

Findings. The redesigned survey questions identify more health insurance coverage than the traditional questions. The resulting lower uninsured rate is more in line with other federal surveys and administrative records.

Conclusions. Our findings suggest that the Affordable Care Act may have changed the way that people respond to the traditional health insurance questions in such a way that may have led to biased estimates of the uninsured rate had the questions not changed.