Hannah Neprash

Hannah Neprash

Assistant Professor, Division of Health Policy and Management, University of Minnesota School of Public Health

Dissertation Title:"Three Essays in Physician Behavior"

Physicians are the foundation of health care in the United States. Their decisions drive both spending and quality of care and it is their actions that will largely determine the success of efforts to achieve a more value-based, sustainable health care system. For this reason, it is crucial to understand how physician behavior responds to the increasing pressures – both financial and workload-related - of modern medicine. These findings have the potential to inform policy regarding health care spending and quality. Primary care physicians face increasing stress to see more patients in the same or less time. This leads to crowded appointment schedules and increased schedule disruptions.

In Paper 1, I examine how physicians respond to schedule disruptions, instrumenting for appointment start time with the office arrival time of the physician's previous patient. I use novel data from athenahealth, Inc., a national provider of electronic health records, medical billing, and practice management services. I find that when primary care physicians fall behind schedule, they truncate appointment duration, perform fewer in-office procedures, and record fewer diagnoses. The likelihood of a patient revisiting the primary care practice within two weeks significantly increases as a function of delayed appointment start time. Physician ordering behavior also responds to a schedule disruption. In particular, physicians who run behind schedule increase antibiotic and opioid painkiller prescribing and increase referrals of a new patient to a specialist. For patients with preexisting prescription drug regimens, physicians running behind schedule are less likely to change the existing course of treatment. These findings suggest possible unintended consequences of the increasing time pressures placed on physicians by policymakers and private payers. Implications may include higher health care spending and lower quality care.

Paper 2 (with Mike Chernew and Michael McWilliams) explores the association between recent changes in provider market structure and changes in spending and prices for commercially insured services. We use Medicare data to observe financial integration between physicians and hospitals and the Truven Health MarketScan database to measure individual-level, annual, commercially insured spending. We find that physician-hospital integration is associated with significantly higher commercial prices and spending for outpatient care, but not inpatient care, suggesting that this type of vertical integration may enhance bargaining power more for the physicians than for the hospitals involved. Despite the prevailing wisdom that payment reform may accelerate consolidation, we find minimal evidence that consolidation was associated with ACO participation, though there is evidence of potential defensive consolidation in response to new payment models.

Paper 3 tests whether primary care physicians’ adjust their labor supply in response to an increase in Medicaid reimbursement. The Affordable Care Act (ACA) greatly increased access to insurance, partially through state Medicaid expansions. In conjunction with this insurance expansion, the ACA increased Medicaid reimbursement for primary care services to national Medicare levels for two years (2013-2014), with the goal of incentivizing physicians to treat more Medicaid patients. The policy change affected physicians differently, based on their state's generosity of Medicaid reimbursement, relative to Medicare rates, prior to the policy change. I use this natural experiment to test whether primary care physicians respond to Medicaid payment increases by changing their Medicaid participation decision and labor supply, as predicted by a mixed-economy model. To do so, I rely on a new database of claims and electronic health record data compiled by athenahealth, Inc., a national provider of electronic health records, medical billing, and practice management services. As predicted, I find evidence that physicians increased their total labor supply in response to the Medicaid payment increase. I do not, however, find any change in Medicaid program participation, except among physicians in states that continued the payment increase beyond 2014. This suggests that the temporary Medicaid primary care payment increase may not have had the intended effect of increasing access to physician services for Medicaid beneficiaries, though a more permanent increase may be more successful.


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