In a new study, investigators found no difference in the performance of radiologists and radiographers double reading screening mammograms-a finding they say could help support the use of physician extenders for breast screening (Radiology 2022; https://doi.org/10.1148/radiol.212951). A team including researchers from the University of Nottingham noted there is "limited evidence on whether trained radiographers, i.e., technologists, may be used to provide double reading." As such, the study authors sought to compare the performance of radiologists and radiographers double reading mammograms, considering reader experience level.
"In many countries, screening mammograms are double read by two physicians, as we know that this increases the ability to detect breast cancers, but, importantly, keeps false-positive recalls low," noted Yan Chen, PhD, Associate Professor of Cancer Screening at the University of Nottingham School of Medicine, and lead author of the study.
In addition to being labor-intensive, this approach leads to a chronic shortage of breast radiologists, stated Chen, noting that facilities in the United Kingdom have long addressed this issue by training radiographers to act as readers in the U.K.'s national breast screening program. "Technologists traditionally perform the mammogram, but after extensive additional training in image interpretation, they can act in a physician extender role to also read mammograms."
Study Details
In a retrospective study, performance and experience data were obtained for radiologists and radiographer readers of all screening mammograms in England from April 2015 to March 2016. Cancer detection rate, recall rate, and positive predictive value of recall based on biopsy-proven findings were calculated for first readers. Performance metrics were analyzed according to reader professional group and years of reading experience using the analysis of variance test. P values less than .05 were considered to indicate statistically significant difference.
Throughout the study period, Chen and colleagues evaluated data from 401 readers, who double read a total of 1,404,395 screening digital mammograms. The readers taking part in the study included 224 radiologists and 177 radiographers. The researchers measured cancer detection rate, recall rate, and positive predictive value. Overall, the investigators saw no statistically significant differences between the groups.
Experience did seem to be a factor, however, as a lower recall rate was seen among readers with more than 10 years of experience, compared to those with 5 years or less experience. And a higher positive predictive value was seen for readers with 10-plus years of experience, compared to those with 5 years of less experience. These rates were consistent regardless of professional group.
"It has been really gratifying to show that there is no difference in the performance of readers from either professional group when we looked at the key breast cancer screening performance metrics of cancer detection rates, recall rates, and the positive predictive value of recall," Chen stated.
Training non-radiologists such as radiographers to read screening mammograms as part of double reading workflow has been routinely done in the U.K. for more than 20 years, explained Chen, adding that the country's recent production of reliable individual reader performance data has made it possible to accurately and thoroughly compare the performance of radiologist and non-radiologist readers. "Our study demonstrates that radiologists and trained non-radiologists acting in a physician extender role can perform equally well reading screening mammograms."
Many factors-an aging population that increases imaging needs, physician burnout in the COVID era-are helping to contribute to a radiologist shortage in many countries, which is being compounded by increasing demands and growing screening backlogs, Chen explained.
"The use of trained radiographer readers in the double-reading workflow may offer a potential solution to the shortage of radiologists experienced by some breast screening programs and lead screening programs in other countries to consider the use of physician extenders in breast imaging," she noted. "Appropriate focused training, participation in external quality assurance schemes like Personal Performance in Mammographic Screening (PERFORMS), and experience are all factors to improve and maintain the performance of readers."
Mark McGraw is a contributing writer.