Universal mammo recall rate target may be off the mark

Screening mammography recall rates were higher at a hospital site compared with a community site, researchers reported in a study published online July 23 in Radiology. The findings call into question the utility of standard recall rate targets.

The Centers for Medicare & Medicaid Services designated the screening mammography recall rate as one of eight physician performance measures in 2006, and the American College of Radiology (ACR) and the Agency for Healthcare Research and Quality recommend a target rate of less than 10 percent.

Despite the universal recall rate goals, the measure is impacted by patient factors, such as age, breast density, use of hormone replacement therapy, interval since the previous mammogram and previous benign biopsy results.

Jason Rothschild, MD, from the department of diagnostic imaging at Alpert Medical School of Brown University in Providence, R.I., and colleagues sought to test the hypothesis that the same radiologist’s recall rate would be higher at an academic center than a community practice because of differences in patient factors.

“If true, it is important to acknowledge this factor when recall rates are compared among different types of facilities and universal recall rate goals are suggested,” they wrote.

The researchers conducted a retrospective review of mammography audit data between May 1, 2008, and Sept. 1, 2011. They focused on five radiologists with breast imaging expertise who read mammograms at an academic medical center and a community practice.

Conditions were similar at both sites. Digital mammograms were acquired and batch-read in a low-light, quiet reading room. Average daily volume at the hospital was 60 screening mammograms, and 89 at the community practice.

The radiologists read 37,691 mammograms at the academic center and 36,606 at the community practice during the study period. The overall mean recall rate at the academic hospital was 8.6 percent vs. 6.9 percent at the community practice. Individual radiologists’ recall rates were between 1.6 and 3.9 percent higher at the academic hospital compared with the community practice.

The patients at the academic hospital had a younger mean age at 56 years compared with 63 years at the community practice, and more women who underwent mammography at the hospital had a history of breast surgery and biopsy. Slightly more than 13 percent of the patients at the hospital site had a history of surgery, compared with 5.6 percent at the community site, and 7 percent of patients at the hospital had undergone a biopsy, compared with 1.4 percent at the community site.

The hospital patients may have had mammograms that were more complicated to interpret or they may have had a higher breast cancer risk, according to the researchers. 

“Our data suggest that patient population factors may affect recall rates at different institutions.”

Rothschild et al noted the lack of data on cancer detection rates at the two facilities. “It is possible that a higher recall rate is necessary in some populations to maintain an appropriate cancer detection rate.”

However, the ACR and federal government rely on a universal recall rate target, a policy the researchers question. “Our data call into question the utility of a universal recall rate goal and suggest that targets may have to be adjusted on the basis of local patient population factors."