There is a debate about the proper age at which to start regular mammogram screenings to detect breast cancer in women who do not have specific risk factors for the disease. As of 2009, the U.S. Preventive Services Task Force recommends waiting until age 50 years to begin mammogram screening for breast cancer and further recommends that screening should occur every 2 years. It also stated, however, that the final decision about the initial timing and frequency of breast cancer screening should be made by the patient and her physician. In making its recommendations, the Task Force found that physicians would need to screen 1,000 women to save 1 woman’s life and concluded that earlier and/or more frequent screening was not worth the harm associated with false positives (anxiety, unnecessary biopsies, overtreatment). Other organizations disagree with the U.S. Preventive Services Task Force and conclude that the lifesaving effects of more routine mammogram screening outweigh the potential harm. Thus, the American Cancer Society recommends having routine annual mammograms from age 45 to 54 years (or 40 if the patient so chooses) and then every 2 years thereafter. The American College of Obstetricians and Gynecologists recommends starting annual mammograms at age 40 years. The idea of comparative effectiveness research is to provide information about the value of different tools. Once that information is available, however, who should make the decisions about whether to provide coverage and reimbursement for a particular good or service? Can one objectively assess the potential harms and benefits associated with mammograms or other services or medications? Should decisions be made solely by the patient and treating provider? Does it matter if decisions affect taxpayers (for example, if a patient is covered by a government program such as Medicare or the Veterans Administration)?