UCLA Anderson School of Management
110 Westwood Plaza, D-513
Los Angeles, CA 90095
NBER Working Papers and Publications
|July 2012||Does it Matter if Your Health Insurer is For-Profit? Effects of Ownership on Premiums, Insurance Coverage, and Medical Spending|
with Leemore Dafny: w18286
The majority of private health insurance in the U.S. is administered or issued by for-profit insurers, but little is known about how for-profit status affects outcomes. We find that plausibly exogenous increases in local for-profit market share induced by conversions of Blue Cross and Blue Shield affiliates in 11 states (and 28 distinct geographic markets) had no significant impact on average premiums, uninsurance rates, or medical loss ratios. However, we do find significant increases in Medicaid enrollment and a reallocation of medical spending toward rivals of BCBS. Moreover, in markets where the converting BCBS affiliate had substantial market share, fully-insured premiums for employer plans increased significantly. The results suggest that the welfare effects of subsidies for new ...
|October 2009||Paying a Premium on Your Premium? Consolidation in the U.S. Health Insurance Industry|
with Leemore Dafny, Mark Duggan: w15434
We examine whether and to what extent consolidation in the U.S. health insurance industry is leading to higher employer-sponsored insurance premiums. We make use of a proprietary, panel dataset of employer-sponsored healthplans enrolling over 10 million Americans annually between 1998 and 2006 to explore the relationship between premium growth and changes in market concentration. We exploit the differential impact of a large national merger of two insurance firms across local markets to estimate the causal effect of concentration on market-level premiums. We estimate real premiums increased by approximately 7 percentage points (in a typical market) due to the rise in concentration during our study period. We also find evidence that consolidation facilitates the exercise of monopsonistic po...
Published: Leemore Dafny & Mark Duggan & Subramaniam Ramanarayanan, 2012. "Paying a Premium on Your Premium? Consolidation in the US Health Insurance Industry," American Economic Review, American Economic Association, vol. 102(2), pages 1161-85, April. citation courtesy of