Adverse Selection in ACA Exchange Markets: Evidence from Colorado

• 成果类型: Article
• 署名作者: Panhans, Matthew
• 刊物名称: AMERICAN ECONOMIC JOURNAL-APPLIED ECONOMICS
• ISSN/ISSBN: 1945-7782
• DOI: 10.1257/app.20170117
• 发表日期: 2019
• 页码: 1-36
• 关键词: insurance markets; health-insurance; moral hazard; INFORMATION; welfare; equilibrium; models

摘要

This study tests for adverse selection in the Affordable Care Act (ACA) health insurance exchanges established in 2014, and quantifies the welfare consequences. Using a new statewide dataset of medical claims from Colorado, I use plausibly exogenous premium variation generated by geographic discontinuities to test for selection. Specifically, each $1 increase in monthly premiums causes a $0.85-0.95 increase in annual medical expenditures of the insured population in 2014, with attenuated effects in 2015. These estimates are consistent with the prevalence of chronic conditions, and difference-in-differences estimates. The results offer the first quasi-experimental evidence of adverse selection in the ACA markets. (JEL D82, G22, H51, H75, I13, I18)