COMMENTS AND RESPONSES Risk Factors for Breast Cancer for Women Aged

TO THE EDITOR: Screening is more effective when the incidence of the target disease is high (that is, more deaths will be prevented while fewer positive screening test results will be false-positive). The idea of optimizing screening effectiveness in women aged 40 to 49 years by targeting those with greater risk for breast cancer is appealing. The review of breast cancer risk factors by Nelson and colleagues (1) may guide physicians on how to provide personalized counseling to pre-menopausal women about the likely benefits and side effects of mammography screening. The review found that breast radiologic density, family history, reproductive history, use of oral contracep-tives, and prior benign breast biopsy were factors associated with higher breast cancer incidence in women aged 40 to 49 years. How-ever, because the primary goal of screening is to decrease the risk for death from breast cancer, it would be more effective for women at higher risk for death and not just at higher risk for diagnosis