Repeat imaging rates higher when scans are interpreted by nurse practitioners, physician assistants
Repeat imaging rates are higher when scans are handled by nonphysician practitioners (NPPs) rather than radiologists, according to new Neiman Health Policy Institute research published Wednesday in JACR.
Previous estimates have shown that 20% to 50% of medical imaging worldwide offers little to no benefit to patients. Common reasons can include experience of the ordering provider, financial incentives, lack of communication, defensive medicine, or a redo of the initial exam due to low quality.
Researchers recently aimed to assess the association between the specialty of the interpreting provider and the likelihood of needing repeat imaging. They believe theirs is one of the first such analyses to tackle this concern, noting that its “clinically and economically relevant,” given rising rates of nurse practitioners and physician assistants handling initial reads.
The study included a total of nearly 1.4 million office-based imaging claims. Of those, about 12.5% had the same exam performed again, with higher odds for nonphysician-interpreted scans across all exam types studied, except for X-rays of the knee.
“Our study does not inform what the ideal repeat-imaging rate is,” Eric W. Christensen, PhD, research director of the Neiman Health Policy Institute, and co-authors concluded. “To the degree that these interpretation rates are greater than the ideal rate, our findings have implications for potentially unnecessary use of medical imaging, which may contribute to system-level unnecessary care and cause patient harm in the form of avoidable worry, additional service utilization and associated costs, and unnecessary radiation exposure.”
For the investigation, Christensen and colleagues utilized fee-for-service Medicare data pulled from the CMS Research Identifiable File. They looked to pinpoint duplicate scans within 90 days after the index study. Unadjusted repeat imaging rates were higher for exams interpreted by NPPs versus radiologists across X-ray (20.4% vs. 14.6%), ultrasound (11.6% vs. 4.5%) and MRI (8.8% vs. 3.8%), the study found. When adjusting for various mitigating factors, the odds of repeat imaging were still higher for NPPs compared to radiologists across all three modalities. By anatomic region, higher repeat imaging odds ranged from 1.39 for shoulder X-ray to 3.4 for abdominal ultrasound, with no statistical significance for knee radiographs.
“Why repeat imaging rates are lower with radiologists is not a question that could be answered by this claims-based study,” the authors noted. “That said, one possibility is that radiologists better document their findings in a report. Consistent with this idea, imaging studies with formal reports were 32% less likely to have repeat imaging. That repeat imaging rates were lower for index studies interpreted by a radiologist may reflect the value of radiologists in reducing unnecessary imaging through quality interpretation and reporting.”
Previous studies have shown that health information exchanges, PACs and clinical decision support systems can help reduce repeat imaging rates, the authors added. Read more about the results, including potential study limitations, in the Journal of the American College of Radiology.
Marty Stempniak has covered healthcare since 2012, with his byline appearing in the American Hospital Association's member magazine, Modern Healthcare and McKnight's. Prior to that, he wrote about village government and local business for his hometown newspaper in Oak Park, Illinois. He won a Peter Lisagor and Gold EXCEL awards in 2017 for his coverage of the opioid epidemic.