Computer-aided detection, a part of almost all mammograms today, appears not to improve diagnostic accuracy for breast cancer screening, according to a large study. Computer-aided detection (CAD) marks areas of concern on mammogram readouts that radiologists might otherwise miss. It was approved by the Food and Drug Administration in 1998 and became common after the Centers for Medicare and Medicaid Services increased reimbursement for the technology in 2002, the authors write. Since then, it has been hard to measure how much difference CAD actually makes in spotting cancers.