Zack Cooper Publications

We use insurance claims data covering 28% of individuals with employer-sponsored health insurance in the United States to study the variation in health spending on the privately insured, examine the structure of insurer-hospital contracts, and analyze the variation in hospital prices across the nation. Health spending per privately insured beneficiary differs by a factor of three across geographic areas and has a very low correlation with Medicare spending. For the privately insured, half of the spending variation is driven by price variation across regions, and half is driven by quantity variation. Prices vary substantially across regions, across hospitals within regions, and even within hospitals. For example, even for a nearly homogeneous service such as lower-limb magnetic resonance imaging, about a fifth of the total case-level price variation occurs within a hospital in the cross section. Hospital market structure is strongly associated with price levels and contract structure. Prices at monopoly hospitals are 12% higher than those in markets with four or more rivals. Monopoly hospitals also have contracts that load more risk on insurers (e.g., they have more cases with prices set as a share of their charges). In concentrated insurer markets the opposite occurs—hospitals have lower prices and bear more financial risk. Examining the 366 mergers and acquisitions that occurred between 2007 and 2011, we find that prices increased by over 6% when the merging hospitals were geographically close (e.g., 5 miles or less apart), but not when the hospitals were geographically distant (e.g., over 25 miles apart). JEL Codes: I11, L10, L11.

This paper examines the link between legislative politics, hospital behavior, and health care spending. When trying to pass sweeping legislation, congressional leaders can attract votes by adding targeted provisions that steer money toward the districts of reluctant legislators. This targeted spending provides tangible local benefits that legislators can highlight when fundraising or running for reelection. We study a provision - Section 508 – that was added to the 2003 Medicare Modernization Act (MMA). Section 508 created a pathway for hospitals to apply to get their Medicare payment rates increased. We find that hospitals represented by members of the House of Representatives who voted ‘Yea’ on the MMA were significantly more likely to receive a 508 waiver than hospitals represented by members who voted ‘Nay.’ Following the payment increase generated by the 508 program, recipient hospitals treated more patients, increased payroll, hired nurses, added new technology, raised CEO pay, and ultimately increased their spending by over $100 million annually. Section 508 recipient hospitals formed the Section 508 Hospital Coalition, which spent millions of dollars lobbying Congress to extend the program. After the vote on the MMA and before the vote to reauthorize the 508 program, members of Congress with a 508 hospital in their district received a 22% increase in total campaign contributions and a 65% increase in contributions from individuals working in the health care industry in the members’ home states. Our work demonstrates a pathway through which the link between politics and Medicare policy can dramatically affect US health spending.