"If I'm better than average, then I'm ok?": Comparative information influences beliefs about risk and benefits.

OBJECTIVE

To test whether providing comparative risk information changes risk perceptions.

METHODS

Two hundred and forty-nine female visitors to a hospital cafeteria were randomized to one of two conditions which differed in whether their hypothetical breast cancer risks was lower or higher than the average women's. Participants read a scenario describing a breast cancer prevention pill and indicated their: (1) likelihood of taking the pill and (2) perception of whether the pill provides breast cancer risk reduction.

RESULTS

Women told that their hypothetical risk of breast cancer was above average were more likely to endorse taking the pill (2.79 vs. 2.23, F=4.95, p=0.002) and more likely to believe that the pill provided a significant risk reduction in breast cancer (3.15 vs. 2.73, F=4.32, p=0.005), even though the risks were equivalent.

CONCLUSIONS

Providing people with comparative risk information changes their risk perceptions. People who have above average risk may feel compelled to take a treatment because they are at above average risk and therefore may not thoroughly consider the trade-offs in the risks and benefits of treatment.

PRACTICE IMPLICATIONS

Physicians and decision aid developers must reconsider the practice of communicating "average risk" information to patients.