The lives saved by population-based mammography screening outweigh the harms caused by overdiagnosis, according to a review of breast cancer screening services in Europe published Sept. 13 in a special supplement of the Journal of Medical Screening. The review showed that for every 1,000 women screened every two years from the age of 50 to the age of about 68 to 69 years, between seven and nine lives would be saved, and four cases of breast cancer would be overdiagnosed.