Health Affairs has published a paper titled: National Expenditure For False-Positive Mammograms And Breast Cancer Overdiagnoses Estimated at $4 Billion A Year. The loaded headline and article, appearing in an otherwise helpful issue on “Cost & Quality of Cancer Care,” add to falsehoods and media-bashing about the alleged costs of breast cancer screening.
The main problems I see are two. The first is in how the authors define a false positive, which is too liberally. The second is the authors’ estimate that “overdiagnosis” occurs in 22 percent of invasive breast cancers in women between the ages of 40 and 59. These assumptions undermine their calculations of mammography’s tab.
False positives (FPs) are a huge deal in screening analyses, and definitions vary. These authors considered a false positive to be any mammogram that leads to further evaluation, such as additional imaging and possibly a biopsy, in a woman who doesn’t have breast cancer. Based on real, recent data from a nationwide, U.S. insurance company for over 702,000 women between the ages of 40 and 59, these authors identified nearly 78,000 women who had FPs, which came to just over 11 percent.
