Survey mode effects and insurance coverage estimates in the redesigned Gallup well-being index.

OBJECTIVE: To test whether a change from a telephone to mail and Internet survey in January 2018 affected the sample composition and uninsured estimates in the Gallup-Sharecare Well-Being Index. DATA SOURCES: Gallup-Sharecare Well-Being Index (2013-2018). STUDY
DESIGN: Regression discontinuity analysis identified changes after the survey redesign in the estimated U.S. uninsured rate (adults 18-64) and in the sample's demographic composition. PRINCIPAL
FINDINGS: After the survey redesign, the estimated uninsured rate fell 5.3 percentage points (P < 0.001), respondents were older and disproportionately white, more likely to have a college degree, and had higher average incomes. These changes were modestly reduced by survey weights.
CONCLUSIONS: The shift to a mail survey (with a web option) led to an older, more educated sample with fewer minorities, and a significant break in trend in the estimated uninsured rate. © Health Research and Educational Trust.