Women's preferences for breast cancer risk-reducing medications: a discrete choice experiment study

Despite strong evidence that chemoprevention reduces breast cancer risk in high-risk women, uptake remains low. We hypothesized that healthy women evaluate preventive medications differently from patients and that understanding delivery preferences may inform more acceptable strategies. We conducted a discrete choice experiment with eight attributes: reduction in lifetime breast cancer risk by age 70, treatment duration, modality, frequency, medical recommendation, fertility impact, side effects, and total cost. Women aged 21-59 without prior breast cancer were recruited in Singapore. Each participant completed choice tasks under two perceived lifetime risk scenarios (30% and 80%). Preferences were analyzed using mixed logit models, with conditional relative importance and marginal willingness-to-pay estimated. Among 618 women, respondents generally preferred risk-reducing treatment over no treatment. Across risk scenarios, shorter duration, minimal fertility impact, and fewer side effects were consistently valued. Cost strongly influenced choices, although less so at higher baseline risk. Cost and side effects were the most important attributes in both scenarios. Willingness-to-pay estimates indicated strong aversion to severe side effects and long durations, and a preference for specialist over general practitioner recommendations. Preferences varied by sociodemographic and clinical characteristics. No significant preference differences were observed across delivery modalities.