Each year in the United States, more than 50,000 Medicare patients die undergoing inpatient surgery. Evidence of wide variations across providers suggests substantial room for improvement. To improve surgical care in the elderly, the Center for Medicare and Medicaid Services (CMS) has launched several policies. However, the extent to which these policies improve outcomes and reduce costs in surgery is unknown. We therefore propose a systematic evaluation of the impact of several policy options on the quality and cost of surgical care in the national Medicare population. With this goal in mind, our current proposal has the following aims:
Aim 1. To evaluate the impact of CMS improvement policies on surgical outcomes. We will conduct evaluations of pay-for-performance, selective referral, bundled payment, and outcomes feedback in the national Medicare population. For each policy approach, we will take advantage of a natural experiment (i.e., a specific program or policy implemented in the last 5 years). To assess outcomes, we will use risk-adjusted mortality and complications for the procedures specifically targeted by the policy. To better control for hospital case-mix and secular trends, we will use a difference-in-difference methodology.
Aim 2. To evaluate the spillover effects of these CMS policies on untargeted surgical conditions. Using national Medicare data, we will examine outcomes for untargeted procedures for which patients receive care from the same surgeons or depend on the same hospital resources. We will assess whether these policies resulted in beneficial spillover effects or caused unintended harm as resources were diverted to the targeted conditions.
Aim 3. To evaluate the impact of these policies on Medicare payments around the surgical episode. We will evaluate Medicare payments for the full range of services that can be linked to complications and poor quality care. We will include payments to the hospital, physicians, readmissions, and post-acute care. The results of this study will facilitate evidence-based policymaking by CMS and other payers. As effective policies for improving care are implemented, surgical patients will be the ultimate beneficiaries of this research.

Public Health Relevance

This study will have immediate real-world impact for CMS policymakers and surgical patients. The results of this proposal will provide CMS with data on the comparative effectiveness of various initiatives for improving quality and decreasing costs. As effective strategies for improving care are implemented by CMS and other payers, surgical patients will be the ultimate beneficiaries of this research.

National Institute of Health (NIH)
National Institute on Aging (NIA)
Research Project (R01)
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Study Section
Special Emphasis Panel (ZRG1-HDM-R (02))
Program Officer
Baker, Colin S
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University of Michigan Ann Arbor
Schools of Medicine
Ann Arbor
United States
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