The Perils Of PECOS

Using Medicare Administrative Data To Answer Important Policy Questions About Health Care Markets

Published in: Health Affairs Blog (January 2021). doi: 10.1377/hblog20201222.615286

Posted on on January 08, 2021

by M. Susan Ridgely, Cheryl L. Damberg, Mark E. Totten, Jose J. Escarce

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We don’t know as much as we should about health systems, and our efforts are hampered by seriously flawed data.

Health care consolidation is sweeping through U.S. health care like a firestorm. In particular, there has been a rapid increase in the vertical integration of hospitals, physicians, and providers of post-acute care into health systems, whether implemented through traditional mergers and acquisitions or new arrangements such as joint ventures, affiliation agreements, and clinically integrated networks. We do not know as much as we should about these health systems, and current efforts to document the relationships among health care providers are hampered by significant limitations in existing data sources.

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