A central question in the US debate over privatized Medicare is whether increased government contributions to private plans generate lower premiums for consumers or higher profits for producers. This research finds that insurance companies pass through 45% of higher payments in lower premiums and an additional 9% in more generous benefits for those who enroll in Medicare Advantage. Since the findings also suggest that the less than full pass-through is a result of insurer market power, efforts to make markets more competitive may be key to increasing the pass-through to consumers.
In evaluating health insurance mergers recently proposed in the U.S., regulators have grappled with the costs and benefits of reduced insurer competition. Our study examines the direct and indirect effects that a reduction in the number of insurers has on premiums, provider reimbursement rates, and consumer welfare. Using detailed health and enrollment data and focusing on a part of the commercial health care market, we examine whether consumers are typically harmed when an insurer is removed from the market. Absent premium setting constraints, we find that premiums typically rise, and consumers are generally harmed as they suffer from having fewer options. However, we also find that the reimbursement rates negotiated by hospitals need not always increase, and in many cases, can actually fall.