Selection and behavioral responses of health insurance subsidies in the long run: Evidence from a field experiment in Ghana
通过加纳田野实验，研究不同补贴水平（1/3、2/3、全额）对保险参保和医疗利用的短期与长期影响，发现一次性补贴长期提升参保率，但仅部分补贴组增加了医疗利用，且事后行为反应而非事前选择是主因。
We study the effects of a health insurance subsidy in Ghana, where mandates are not enforceable. We randomly provide different levels of subsidy (1/3, 2/3, and full) and evaluate the impact at 7 months and 3 years after the intervention. We find that a one-time subsidy increased insurance enrollment for all groups in both the short and long runs, but health care utilization in the long run increased only for the partial subsidy group. We find supportive evidence that ex-post behavioral responses rather than ex-ante selective enrollment explain the long-run health care utilization results.