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Influence of Provider Continuity on Patient Health-Related Behavior and Outcomes
Provider continuity occurs when a patient is treated by the same provider over time. Provider discontinuities, defined as breaks in continuity, could affect the quantity and quality of healthcare. Loss of access to providers results in loss of relationship capital, including knowledge and trust. Patients face search costs (e.g., finding in-network provider) and transaction costs (e.g., transferring medical records) in obtaining new providers. Provider continuity likely benefits many patients, such as through better preventive care and chronic conditions management. On the other hand, some patients who switch providers could receive valuable second opinions, which could counteract the negative effects of provider discontinuities. My research uses provider discontinuities to understand the influence of continuity on patient behavior and outcomes.
I identify the effects of provider continuity on patient behavior and outcomes using two approaches. First, I use an event study research design with provider discontinuity events that are arguably exogenous to patients, specifically physician exits from the profession and relocations outside their provider markets. Second, among patients whose providers relocate within their provider markets, I use both event study and instrumental variable approaches to compare effects of discontinuities with individual physicians and effects of discontinuities with entire group practices. The instruments for provider discontinuity are functions of patient distance to the provider’s new location, which is plausibly exogenous.
My analyses use medical claims data, including the CMS 20% sample of Original Medicare patients during 1999-2012, and upon approval, the Massachusetts All Payer Claims Database patients during 2010-2014. I focus on primary care physicians (PCPs), since continuity with PCPs may be particularly important, and I will also examine results with other outpatient clinicians. I measure effects of provider continuity on major health events (e.g., hospitalizations, mortality), spending, and efficiency. I also measure effects on medical care use (e.g., frequency and quantity of preventive, primary, specialty, and emergency care), drug use (e.g., adherence), and new diagnoses.
Effects of provider continuity have important implications for healthcare access, quality, and efficiency. New enrollees in narrow and limited network plans may find that their providers become out-of-network and have large incentives to switch to in-network providers. If provider discontinuities result in worse healthcare, then governments could regulate narrow network plans and mandate minimum periods of access to out-of-network providers for new plan enrollees. Employers could offer health plans with less restrictive networks. Furthermore, if provider discontinuities result in healthcare delays, then Medicare, Medicaid, and health plans could help patients proactively find new providers. Integrated health systems, Accountable Care Organizations (ACOs), and other provider organizations could promote provider continuity through scheduling. Finally, if provider continuity matters for only certain physicians, then policies could focus on the relevant providers.