Over a seven-year period, the team from the Group Health Centre for Health Studies in Seattle, Washington, studied 123 radiologists who looked at 36,000 diagnostic mammograms - performed when a screening mammogram has highlighted breast concerns, at 72 US facilities.
They found the number of false-positive results ranged from 0% to 16%, and that the radiologists’ sensitivity – their ability to accurately detect cancer, ranged from 27% to 100%.
Study author Diana Miglioretti said: ‘I was expecting diagnostic mammograms to be less variable than screening mammograms. The variability in performance is concerning and likely affects many women with and without breast cancer.’
Ways to improve interpretations of diagnostic mammography should be investigated, she added in the Journal of the National Cancer Institute.