UCLA

The United States spends a larger percentage of GDP on healthcare than any other OECD nation, and yet it performs poorly on measures of access, process quality and outcomes relative to other wealthy nations. One hypothesis that may explain the relatively poor performance of the United States' healthcare system per dollar spent is that markets for hospitals, physician services, and insurance are highly consolidated and lack competition. This dissertation contributes to the body of literature seeking to measure healthcare market structure and assess the relationship between this market structure and unit prices, overall spending, and healthcare quality.The first paper in this dissertation, “The Association between Hospital-Physician Vertical Integration and Outpatient Physician Prices Paid by Commercial Insurers: New Evidence,” demonstrates market-level associations between vertical integration among hospitals and physicians and higher prices for outpatient care. The second essay, “How Hospital-Owned Physician Organizations are Associated with Healthcare Prices, Expenditures, and Quality,” analyzes vertical integration and prices, quality, and total patient spending, building on the findings of the first essay using physician and hospital level claims data. This study finds that vertical integration is associated with higher levels of annual spending for patients attributed to vertically integrated providers, but interpretation of association between vertical integration and outpatient prices is confounded by pre-intervention trends. Analysis of CMS hospital outcome measures does not show associations between vertical integration at a hospital level and quality. Finally, the third essay, “Automated Delineation of Hospital Market Boundaries in California,” explores geographic market definition in healthcare, an important topic in research and antitrust action, while assessing the application of community detection methods in this field. This study finds that community detection methods group hospitals with higher accuracy than other geographic markets as measured by patient flows and may offer promise for merger screening, research on market concentration, and research on geographic variation in healthcare. The final chapter reviews overarching limitations of the dissertation, outlines directions for future research, and comments on potential policy approaches to promote competition and address the symptoms that may result from highly consolidated healthcare markets.