Women's perceptions of breast cancer risk: are they accurate?

Background: The objective was to compare women's personal estimates of their risk with objective breast cancer risk estimates and to describe the risk factors for breast cancer identified by women.

Methods: Telephone survey of a random sample of 761 rural and urban women with no history of breast cancer. Survey instrument included measures of perceptions of lifetime risk for breast cancer for themselves and for the average woman, perceptions of risk factors that influenced their risk and the average woman's risk for breast cancer. Objective estimates of breast cancer risk were calculated using the Gail et al. algorithm. Descriptive statistics and multiple linear regression were used to analyze the data.

Results: Women's estimates of their own lifetime risk for breast cancer were significantly higher than their Gail model risk estimates (mean difference = 19%, p < 0.001). The women's personal breast cancer risk estimates were lower than estimates of risk for a hypothetical average woman (mean difference = -8%, p < 0.001). Fifty percent of the sample reported a perceived risk estimate at least 15% above their Gail risk estimate. The risk factors for breast cancer most frequently identified included family history, nutrition/diet, smoking, lifestyle, environment, stress and age. Although the risk factors used to calculate the Gail model risk estimates were reported by some study participants, these women consistently identified only family history as their personal risk factor.

Conclusion: Women have difficulty accurately estimating their breast cancer risk and identifying known risk factors for breast cancer. Individual risk information may be more useful in enhancing accurate risk perceptions than the "1 in 9" message.