The effect of Medicaid premiums on enrollment: a regression discontinuity approach.

This paper estimates the effect that premiums in Medicaid have on the length of enrollment of program beneficiaries. Whether and how low income-families will participate in the exchanges and in states' Medicaid programs depends crucially on the structure and amounts of the premiums they will face. I take advantage of discontinuities in the structure of Wisconsin's Medicaid program to identify the effects of premiums on enrollment for low-income families. I use a 3-year administrative panel of enrollment data to estimate these effects. I find an increase in the premium from 0 to 10 dollars per month results in 1.4 fewer months enrolled and reduces the probability of remaining enrolled for a full year by 12 percentage points, but other discrete changes in premium amounts do not affect enrollment or have a much smaller effect. I find no evidence of program enrollees intentionally decreasing labor supply in order to avoid the premiums.