evidence: The benefits and the harms of mammography came as a surprise to nearly half the study's participants. More than one-quarter said what they learned from the study about overdiagnosis differed from what their doctors told them. [...] For the past 28 years, the influential U.S. Preventive Services Task Force has been flip-flopping in its recommendations about when women should begin mammography screening. [...] An editorial accompanying the new study stresses the need for education about mammography and the value of shared decision-making between clinicians and patients.