3641 Locust Walk, Colonial Penn Center
Philadelphia, PA 19104
Ambar will be joining Columbia University’s Mailman School of Public Health as an Assistant Professor of Health Policy and Management in August 2019.
Ambar is a PhD Candidate in Wharton’s Health Care Management and Economics department. She uses quantitative and qualitative methods to study the business strategies of organizations in the health care sector. This includes research on the impact of mergers and acquisitions on the cost and quality of health care. She is also interested in how information asymmetries and incentives can shape health care provider behavior.
Prior to Wharton, Ambar worked in Washington, DC as a policy analyst for the Quantitative Economics and Statistics group of Ernst and Young. She graduated from Swarthmore College in 2011 with honors in Economics and Mathematics.
“Physician Organization and Incentives in Childbirth: Evidence from Physician Practice Management Companies” (Job Market Paper)
This paper studies a growing form of medical practice consolidation: the Physician Practice Management Company (PPMC). Over 60,000 physicians have joined PPMCs to increase their collective market power and leverage economies of scale. In contrast to acquisitions by hospitals, physicians in a PPMC retain autonomy over the clinical and operational decisions of their practice. PPMCs, however, can influence physician behavior by using a combination of financial incentives, such as providing physicians with equity in the PPMC, and non-financial incentives, such as distributing peer comparison reports. In this paper, I analyze novel data on three PPMCs that represent 40% of Obstetricians and Gynecologists (Ob-Gyns) in Florida to study how PPMCs influence Ob-Gyn treatment decisions. The empirical analysis estimates changes in C-section rates by linking data on the staggered timing of Ob-Gyn practice acquisitions to hospital discharge records between 2006 and 2014. This treatment decision presents a trade-off between revenue and quality: C-sections are more highly reimbursed than vaginal births but pose risks to maternal and infant health when not medically necessary. I find that Ob-Gyns increase C-sections among low-risk mothers by 8-10% after joining PPMCs that only incentivize financial performance. Instead, when Ob-Gyns join a PPMC that incentivizes both financial and clinical performance, low-risk C-sections decrease by 22%. The rise in C-sections occurs among less medically appropriate patients and results in increased morbidity, while treatment becomes more appropriate when the C-section rate declines. I also test for changes in birth volume and C-sections by payer type to examine the role of financial incentives. This research provides new insights into how the business strategies of physician organizations affect the utilization of medical treatments and the quality of care.
Work in Progress
“In Search of Quality: The Effect of Online Physician Ratings on Consumer and Physician Behavior”
“Hospital Strategy and the Urban-Rural Divide: Implications for Labor and Delivery” (with Emma Boswell Dean)
La Forgia, A., Maeda, J. L., & Banthin, J. S. (2017). Are Integrated Plan Providers Associated with Lower Premiums on the Health Insurance Marketplaces? Medical Care Research and Review, 75(2), 232-259.
– Media Coverage: The Upshot, New York Times
As the health insurance industry becomes more consolidated, hospitals and health systems have started to enter the insurance business. Insurers are also rapidly acquiring providers. Although these “vertically” integrated plan providers are small players in the insurance market, they are becoming more numerous. The health insurance marketplaces (HIMs) offer a unique setting to study integrated plan providers relative to other insurer types because the HIMs were designed to promote competition. In this descriptive study, the authors compared the premiums of the lowest priced silver plans of integrated plan providers with other insurer types on the 2015 and 2016 HIMs. Integrated plan providers were associated with modestly lower premiums relative to most other insurer types. This study provides early insights into premium competition on the HIMs. Examining integrated plan providers as a separate insurer type has important policy implications because they are a growing segment of the marketplaces and their pricing behavior may influence future premium trends.
La Forgia, A., & Burns, L. R. (2017). Health Insurance in China. In L.R Burns & G. Liu (Eds.), China’s Health Care System and Reform (pp. 291-320). Cambridge, UK: Cambridge University Press.
This volume provides a comprehensive review of China’s healthcare system and policy reforms in the context of the global economy. Following a value-chain framework, the 16 chapters cover the payers, the providers, and the producers (manufacturers) in China’s system. It also provides a detailed analysis of the historical development of China’s healthcare system, the current state of its broad reforms, and the uneasy balance between China’s market-driven approach and governmental regulation. Most importantly, it devotes considerable attention to the major problems confronting China, including chronic illness, public health, and long-term care and economic security for the elderly. Burns and Liu have assembled the latest research from leading health economists and political scientists, as well as senior public health officials and corporate executives, making this book an essential read for industry professionals, policymakers, researchers, and students studying comparative health systems across the world.
Business Economics and Strategy
Introduction to Business Economics and Public Policy, 2016
Teaching Assistant for Katja Seim [Mixed MBA and Undergraduate Course]
Non-Profit Sector: Economic Challenges and Strategic Responses, 2015
Teaching Assistant for Ashley Swanson [Undergraduate Course]
Cuba Before and After Normalization of US Relations, 2015 & 2016
Teaching Assistant for Patricia Danzon, Olivia Mitchell and Kent Smetters [Executive MBA Course]
Health Care Management
The US Health Care System, 2016
Teaching Assistant for Lawton R. Burns [Executive MBA Course]
Health Services Research: Applied Econometrics, 2016
Teaching Assistant for Scott Harrington [PhD Course]
Health Services Systems, 2014 & 2015
Teaching Assistant for Lawton R. Burns. [MBA Course]
Grants and Fellowships
Dissertation Grant R36 HS26397-01, 2018 – 2019
Agency for Healthcare Research and Quality
Mack Institute for Innovation Management Research Fellowship, 2018 – 2019
The Wharton School
Graduate Research Fellowship Program in Economics, 2015 – 2018
National Science Foundation
President Gutmann Leadership Award, 2018
University of Pennsylvania
George James Term Fund Research Travel Award, 2018
The Wharton School
Penn Prize for Excellence in Teaching by Graduate Students, 2016
1 of 10 recipients across University
University of Pennsylvania
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