Radiologists' workloads grew substantially in the past few years, with procedures increasing 7 percent and physician work relative value units (RVUs) increasing 10 percent from 2002-2003 to 2006-2007, according to research published in this month's Radiology.

Mythreyi Bhargavan, PhD, from the research department at the American College of Radiology (ACR) and the department of radiology and radiological science at Johns Hopkins University in Baltimore, and colleagues sought to determine radiologists' workloads in 2006-2007. The team measured procedures per full-time equivalent (FTE) radiologist and RVUs per FTE radiologist, and sought to discover trends since 1991-1992 using data from the ACR 2007 survey of radiologists. They evaluated workload according to individual practice characteristics, such as academic, private or multispecialty for statistically significant differences from the average for all radiologists.

In 2006-2007, the researchers reported that the average annual workload per FTE radiologist was 14,900 procedures, an increase of 7 percent since 2002-2003 and 34 percent since 1991-1992. Annual RVUs per FTE radiologist were 10,200, an increase of 10 percent since 2002-2003 and 70.3 percent since 1991-1992.

Bhargavan and colleagues found that academic practices performed about one-third fewer procedures per FTE radiologist than others. In most types of practice, radiologists in a 75th-percentile practice performed at least 65 percent more procedures annually than radiologists in a 25th-percentile practice. The researchers said that their regression analysis showed that practices that used external off-hours teleradiology services performed 27 percent more procedures than otherwise similar practices that did not use these services.

"Differences in hours of work explain a bit of this variation, but there are no obvious explanations for differences this large," they wrote.

Workload varied substantially among similar practices, the researchers wrote, for reasons that remain "unknown despite intensive investigation." They stated that though the data should not be used as standards, the study provides reliable information about radiologists' workloads and trends.

The authors noted that radiologists have been able to increase their workload by such large amounts while keeping their annual work hours relatively fixed through the use of new technology, "whether that technology is embodied in equipment and software--for example, in PACS and 3D reconstruction--or in organizational arrangements, such as the use of external off-hours teleradiology services."