Competition and Voluntary Disclosure of Quality Information: Theory and EmpiricalEvidence from HMO Markets. Abstract and Executive Summary of Dissertation

摘要

My dissertation investigates how market mechanism alleviates asymmetricinformation about health care service quality between sellers and buyers. Specifically, I first examine what factors motivate health maintenance organizations (HMOs) to voluntarily disclose private information about their own service quality through the National Committee of Quality Assurance (NCQA). I find that competition plays a prominent role in encouraging disclosures. In comparison, disclosure costs and local demand factors explain some cross-sectional variations in disclosure decisions but contribute little to explaining changes in disclosures over time. Second, I investigate how Medicare beneficiaries respond to the NCQA information in their actual choices of health plans. I find mixed evidence. After controlling for contract-county fixed effects, one set of the information, i.e., whether a plan participates in the NCQA HEDIS report, has positive and significant impact on consumer choice of health plan. This is consistent with the theoretical predication that disclosing HMOs are likely to be high quality firms. But the effect of another set of information, i.e., whether a plan has sought accreditation via the NCQA, is sensitive to competitive environments and the extent to which an HMO devote its service to Medicare patients.