RESUMO
OBJECTIVES: To evaluate postmenopausal women's knowledge of the risk of breast cancer associated with the use of hormone therapy (HT) and their perception of this risk when presented as a relative risk (RR), absolute risk (AbR) or attributable risk (AR). METHODS: A cross-sectional study was conducted with 402 postmenopausal women. The participants answered a self-response questionnaire in which data on the risk of breast cancer associated with HT were presented in the form of RR, AbR and AR. The women's concern with respect to this risk and their changes of opinion when the data were presented according to the different risk models were evaluated. RESULTS: More than 87% of the women mentioned breast cancer as one of the risks associated with the use of HT, with more women being concerned when the risk was presented as an RR. In contrast, most were unconcerned when the risk was presented as an AbR or AR. For the group as a whole, there was a significant change in opinion with respect to the women's concern regarding the risks when they were presented as an AbR or AR (p < 0.001); however, this was not the case for those women who had initially stated that breast cancer was a risk associated with HT. CONCLUSIONS: Providing information on breast cancer risk using examples that quantify the incidence of the disease provokes less concern in users and candidate users of HT. Changes of opinion occur when explanations regarding the risk are provided as RR, AbR and AR.