Outcomes of primary care delivery by nurse practitioners: Utilization, cost, and quality of care.

Objective To examine whether nurse practitioner (NP)-assigned patients exhibited differences in utilization, costs, and clinical outcomes compared to medical doctor (MD)-assigned patients. Data Sources Veterans Affairs (VA) administrative data capturing characteristics, outcomes, and provider assignments of 806 434 VA patients assigned to an MD primary care provider (PCP) who left VA practice between 2010 and 2012. Study Design We applied a difference-in-difference approach comparing outcomes between patients reassigned to MD and NP PCPs, respectively. We examined measures of outpatient (primary care, specialty care, and mental health) and inpatient (total and ambulatory care sensitive hospitalizations) utilization, costs (outpatient, inpatient and total), and clinical outcomes (control of hemoglobin A1c, LDL, and blood pressure) in the year following reassignment. Principal Findings Compared to MD-assigned patients, NP-assigned patients were less likely to use primary care and specialty care services and incurred fewer total and ambulatory care sensitive hospitalizations. Differences in costs, clinical outcomes, and receipt of diagnostic tests between groups were not statistically significant. Conclusions Patients reassigned to NPs experienced similar outcomes and incurred less utilization at comparable cost relative to MD patients. NPs may offer a cost-effective approach to addressing anticipated shortages of primary care physicians.