Rising health care costs, physician shortages, and an aging patient population have increased the demand and utilization of advanced practice providers (APPs). Despite their expanding role in care delivery, little research has evaluated the care delivered by APPs compared with physicians.

We used clinical patient simulations to measure and compare the clinical care offered by APPs and physicians, collecting data from 4 distinct health care systems/hospitals in the United States between 2013 and 2017. Specialties ranged from primary care to hospital medicine and oncology. Primary study outcomes were to 1) measure any differences in practice patterns between APPs and physicians, and 2) determine whether the use of serial measurement and feedback could mitigate any such differences.

At baseline, we found no major differences in overall performance of APPs compared with physicians (P = .337). APPs performed 3.2% better in history taking (P = .013) and made 10.5% fewer unnecessary referrals (P = .025), whereas physicians ordered 17.6% fewer low-value tests per case (P = .042). Regardless of specialty or site, after 4 rounds of serial measurement and provider-specific feedback, APPs and physicians had similar increases in average overall scores—7.4% and 7.6%, respectively (P < .001 for both). Not only did both groups improve, but practice differences between the groups disappeared, leading to a 9.1% decrease in overall practice variation.

We found only modest differences in quality of care provided by APPs and physicians. Importantly, both groups improved their performance with serial measurement and feedback so that after 4 rounds, the original differences were mitigated entirely and overall variation significantly reduced. Our data suggest that APPs can provide high quality care in multiple clinical settings.