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Abstract Many industries have become increasingly concentrated through mergers and acquisitions, which in health care may have important consequences for spending and outcomes. Using a rich panel of Medicare claims data for nearly one million dialysis patients, we advance the literature on the effects of mergers and acquisitions by studying the precise ways providers change their behavior following an acquisition. We base our empirical analysis on more than 1,200 acquisitions of independent dialysis facilities by large chains over a 12-year period and find that chains transfer several prominent strategies to the facilities they acquire. Most notably, acquired facilities converge to the behavior of their new parent companies by increasing patients’ doses of highly reimbursed drugs, replacing high-skill nurses with less-skilled technicians, and waitlisting fewer patients for kidney transplants. We then show that patients fare worse as a result of these changes: outcomes such as hospitalizations and mortality deteriorate, with our long panel allowing us to identify these effects from within-facility or within-patient variation around the acquisitions. Because overall Medicare spending increases at acquired facilities, mostly as a result of higher drug reimbursements, this decline in quality corresponds to a decline in value for payers. We conclude the article by considering the channels through which acquisitions produce such large changes in provider behavior and outcomes, finding that increased market power cannot explain the decline in quality. Rather, the adoption of the acquiring firm’s strategies and practices drives our main results, with greater economies of scale for drug purchasing responsible for more than half of the change in profits following an acquisition.
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as2org+: Enriching AS-to-Organization Mappings with PeeringDB
An organization-level topology of the Internet is a valuable resource with uses that range from the study of organizations’ footprints and Internet centralization trends, to analysis of the dynamics of the Internet’s corporate structures as result of (de)mergers and acquisitions. Current approaches to infer this topology rely exclusively on WHOIS databases and are thus impacted by its limitations, including errors and outdated data. We argue that a collaborative, operator-oriented database such as PeeringDB can bring a complementary perspective from the legally-bounded information available in WHOIS records. We present as2org+, a new framework that leverages self-reported information available on PeeringDB to boost the state-of-the-art WHOIS-based methodologies. We discuss the challenges and opportunities with using PeeringDB records for AS-to-organization mappings, present the design of as2org+ and demonstrate its value identifying companies operating in multiple continents and mergers and acquisitions over a five-year period.
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- Award ID(s):
- 2107392
- PAR ID:
- 10535305
- Publisher / Repository:
- Passive and Active Measurement (PAM) 2023
- Date Published:
- ISBN:
- 978-3-031-28485-4
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Conference Paper:
- The DOI is not currently available.
