Informed Decision-Making and Breast Cancer Screening

In a recent Lancet publication, Hersch et al reported findings on the influence of alternative-content decision aids on knowledge, attitudes, and intentions related to breast cancer screening.1 The alternative decision aid booklets were provided to 879 women aged 48–50 in New South Wales, Australia who were approaching the target age to begin breast cancer screening. Briefly, the authors randomized 440 women to an intervention group which received a breast screening information booklet that included quantitative information on overdiagnosis, and 439 to a control group that received the same information booklet without reference to overdiagnosis. The authors then administered a questionnaire to all randomized women, on knowledge, attitudes, and intentions relating to breast cancer screening. Based on a woman’s answers, the researchers classified each woman on whether she had made an informed choice about breast cancer screening (defined as adequate knowledge and intentions consistent with attitudes). The authors concluded that women in the intervention group were more likely to make an informed choice, due to their greater knowledge about overdiagnosis. In addition, fewer women in the intervention group than in the control group intended to be screened (74% v 87%; p < 0.001). A companion editorial suggests that accompanying an offer of screening with information is necessary but not sufficient for informed choice, because various factors influence how that information is processed. The authors of the editorial also assert that there is a major ethical dilemma in screening, ie. while some will receive a net benefit from screening, some will receive a net harm.2