Does Abolishing a Copayment Increase Doctor Visits? A Comparative Case Study.

Insurance coverage increases health care consumption, but less is known whether moderate copayments affect adults' primary care utilization in a system characterized by gatekeeping. We analyze whether abolishing a 14-euro copayment for visits to general practitioners (GP) in Helsinki, the capital of Finland, increased the number of GP visits among adults and especially among low-income individuals. Using a difference-in-differences (DD) design and combining several administrative registers from 2011 to 2014, we find that the abolition is associated with only a small increase in GP visits (+0.04 visits annually, or +4.4 %, for all adults). The increase is driven by low-income adults (+0.06 visits, or +4.5 %, at the bottom 40 %). Although the point estimates are rather robustly positive, the conclusions regarding the statistical significance are sensitive to how we account for clustering in a setting characterized by only one treated cluster and a finite number of comparison clusters. [ABSTRACT FROM AUTHOR]