Physician assistants order imaging, and particularly CT, at rates higher than primary care doctors, according to a large-scale analysis published in the Journal of the American College of Radiology.

Researchers recently set out to determine whether patients in racial or ethnic minority groups face disparities in the ordering or imaging exams at the primary care setting. They found similar or higher rates of examinations when compared to white patients, based on a sample representing 2.8 billion patient visits.

However, the study’s authors did unearth higher rates of imaging orders among PAs, a finding that may warrant further attention from radiology leadership.

“Our study has significant implications for promoting an equitable, just, and economically efficient healthcare system,” leader author Sue Y. Yi, PhD, with the Department of Radiology at the University of Wisconsin School of Medicine and Public Health, and colleagues wrote July 6 [1]. “The absence of disparities in imaging use for minority patients in primary care clinics highlights the importance of ensuring access to high-quality primary care as a means of promoting health equity. However, the potential overutilization of imaging by advanced practice providers indicates a need to continue to promote high-value imaging for all. Measures—such as clinical decision support tools—to optimize the value of imaging will be necessary as the strained primary care physician workforce is increasingly augmented by other healthcare providers.”

For the analysis, Yi et al. used National Ambulatory Medical Care Survey cross-sectional data, spanning 2013 to 2018. They included all visits to primary care clinics during this time frame. The data’s survey weighting was accounted for to produce valid, national-level estimates of imaging use across all U.S. office-based PCP encounters.

Providers ordered diagnostic imaging in about 12.5% of visits, with X-rays requested most frequently (4.3%) and MRI least often (0.8%). Meanwhile, the use of radiology services was similar or higher among minority patients when compared to their white, non-Hispanic counterparts. Patient factors including female sex, increasing age and comorbidities such as cancer predicted higher rates of imaging. Individuals also were less likely to undergo imaging when seeing their own PCP.

Meanwhile, physician assistants ordered imaging at rates higher than medical doctors, including a 6.5% clip of requesting CT scans compared to 0.7% for MDs and DOs.

“This finding has important implications for the delivery of primary care services, particularly as the use of [advance practice providers] in primary care continues to increase,” the authors advised. “The challenge will be to find ways to maintain high-quality, cost-effective care for all patients while addressing the potential overuse of imaging by some providers. Although the appropriateness of any individual imaging exam cannot be determined from this data set, it is concerning that higher rates of imaging use by APPs may represent overutilization.”

Read much more about the study’s results, including potential limitations, in JACR at the link below.