The USPSTF found fair evidence that women who have screening mammography die of breast cancer less frequently than women who do not have it and the benefits are greatest and best defined for women aged 50 to 74 years. The benefits minus harms are smaller for women aged 40 to 49 years. Benefits increase as women age and their risk for breast cancer increases. However, there are relatively few studies of mammography for women aged 75 years or older. In addition to anxiety and additional procedures due to false-positive test results, the greatest potential harm of mammography is overdiagnosis. Overdiagnosis means receiving a diagnosis and treatment of cancer that never would have surfaced on its own within a woman's natural lifetime. The USPSTF found that the benefit of mammography every 2 years is nearly the same as that of doing it every year, but the harms are likely to be half as common. They found that there is not enough information to assess the benefits and harms of supplemental screening for women with dense breasts or newer screening tests, such as DBT or MRI.