September 17, 2026
Individual IR focus and Evaluation and Management Services Facilitate Higher Complexity IR Practice
A new study from the Harvey L. Neiman Health Policy Institute found that both practice-level and radiologist-level IR specialization are associated with increasing procedural complexity, and nurse practitioners and physician assistants (NPPs, non-physician practitioners), through the provision of evaluation and management (E&M) services, contributed to increased procedural complexity to the interventional radiologists they support. This practice-level analysis was published in the Journal of the American College of Radiology (JACR) and based on 29,844 radiology practice-years over the 2008-2023 period.
The study found that odds of radiologist-performed higher complexity procedures (>5 work relative value units [wRVUs]) increased as practice and individual radiologist IR focus increased. These odds were 75-fold higher for individual IR focus (>90-100% versus >0-10% IR-related work) and 62% higher for practice IR focus.
“We found that practices with a greater IR focus were associated with higher procedural complexity for radiologists, but association between procedural complexity and individual radiologist IR focus was substantially stronger,” stated Luke Wilkins, MD, professor of vascular and interventional radiology at the University of Virginia, and study lead author. “Hence, practice environments may enable complex care, but they do not substitute for individual IR immersion.”
“Outside the most highly IR specialized practices, those with >90-100% IR-related work, incremental increases in practice-level IR share had a relatively limited impact compared with radiologist-level specialization,” said Eric Christensen, PhD, research director at the Neiman Institute and study senior author. “This suggests that while practice infrastructure, referral networks, and organizational focus are necessary to support complex IR care, they do not independently drive complexity without corresponding increases in individual physician engagement.”
The authors found that higher provision of E&M visits was associated with increased procedural complexity provided by radiologists. This was true for the E&M services provided by the radiologists themselves, but also for the E&M services provided by the NPPs supporting them. Notably, NPP-provided E&M was particularly impactful on the procedural complexity for majority-IR radiologists.
“The association between NPP-provided E&M services and increased procedural complexity underscores the importance of team-based care models in enabling complex IR practice, particularly among radiologists with majority IR-related work. NPPs may expand clinical capacity, facilitate longitudinal care, and allow radiologists to focus on more technically demanding procedures,” stated Dr. Wilkins.
“While the integrated and independent IR residency pathway has emphasized longitudinal patient care, clinic-based practice, and full ownership of the care episode. Yet, national practice pattern analyses have demonstrated substantial heterogeneity in how IR is practiced, with many self-identified interventional radiologists continuing to perform a minority of IR-related work and maintaining hybrid diagnostic roles,” explained Dr. Wilkins. “Our findings help reconcile these observations by demonstrating that procedural complexity is most closely tied to the degree to which individual physicians are IR focused, rather than simply the overall composition of the practice.”
“Radiology practice consolidation has resulted in fewer, larger practices despite growth in the number of radiologists and has been associated with increased opportunities for subspecialization,” stated Dr. Christensen. “Future studies should evaluate whether a concentrated group of interventional radiologists within an otherwise predominantly diagnostic radiology practice can support high-complexity IR work similarly to a predominantly IR-focused practice.”
To arrange an interview with a spokesperson, contact Nichole Gonzalez at ngonzalez@neimanhpi.org.
About the Harvey L. Neiman Health Policy Institute
The Harvey L. Neiman Health Policy Institute is one of the nation’s leading medical imaging socioeconomic research organizations. The Neiman Institute studies the role and value of radiology and radiologists in evolving health care delivery and payment systems and the impact of medical imaging on the cost, quality, safety and efficiency of health care. Visit us at www.neimanhpi.org and follow us on X, BlueSky or LinkedIn.