CHICAGO—The vast proportion (81 percent) of radiologists’ noninvasive diagnostic imaging relative value units (RVUs) is conducted in hospital settings, as opposed to private offices, according to  a scientific poster presented at the 2012 Radiological Society of North America (RSNA) conference. If office-based practice is used as a gauge for the entrepreneurial nature of physicians, radiologists may not fit the mold.

“Among the medical specialties, radiologists have been known as the highest-earning physicians, which has created the impression that radiologists are entrepreneurs, looking for profit-making ventures,” the study’s senior author David C. Levin, MD, professor emeritus of radiology at Thomas Jefferson University in Philadelphia, told Health Imaging. “The fact that radiologists are successful has created this impression that they are entrepreneurial.”

The study authors noted that the amount of work radiologist do in private offices is “one important measure of radiologist entrepreneurship.” Thus, they sought to determine what proportion of noninvasive diagnostic imaging work done by radiologists occurred in offices.

Using the Medicare’s Physician/Supplier Procedure Summary Master Files for 2000-2010, the researchers assessed the Medicare specialty codes to identify radiologists and they used place-of-service codes to identify studies done in private offices. “These codes allow researchers to separate out studies that are performed in hospital outpatient facilities from those that are performed in private offices from those that are performed on hospital inpatients from those that are performed on ER patients,” explains Levin.

The researchers also tabulated global and professional component claims for all types of noninvasive diagnostic imaging. They assigned applicable total professional component RVUs to each noninvasive diagnostic imaging CPT code and RVU rates per 1,000 Medicare beneficiaries. RVU rates reflect workload and costs and were therefore a better metric than utilization rates based on volume, according to the study authors. Levin added that they only included studies that were performed by radiologists, not MR exams conducted by orthopedics or CT scans conducted by urologists.

In 2000, radiologists performed 237 professional component RVUs per 1,000 Medicare beneficiaries in private offices, increasing to 426 per 1,000 in 2010—a compound annual growth rate of 6 percent. Most of the growth occurred during the early part of the study period; from 2006-2010 the average annual change was negative 0.4 percent.

A total of 81 percent of radiologists’ noninvasive diagnostic imaging RVUs is conducted in hospital settings, with 19 percent being practiced in the private office setting. In 2000, this figure of the private office setting had been 16.2 percent. “There has been relatively little growth in private practice imaging conducted by radiologists in the last decade,” Levin said.

Among the other primary places-of-service where imaging was performed by radiologists in 2010, hospital outpatient facilities accounted for 38.1 percent, hospital inpatients 28 percent and emergency departments 14.6 percent—all of which contributed to the approximate 81 percent of noninvasive procedures in the hospital setting.

Looking at all outpatient imaging together (both offices plus hospital outpatient facilities), twice as much of it is done in hospital facilities as in private offices, the study authors concluded. “Radiology remains largely a hospital-based specialty, and radiologists do not appear to be as entrepreneurial as some might think,” they wrote.