Objective: This study examines the effects of a mammography decision intervention on perceived susceptibility to breast cancer (PSBC) and emotion and investigates how these outcomes predict mammography intentions.
Design: Randomised between-subjects online experiment. Participants were stratified into two levels of risk. Within each stratum, conditions included a basic information condition and six decision intervention conditions that included personalised risk estimates and varied according to a 2 (amount of information: brief vs. extended) × 3 (format: expository vs. untailored exemplar vs. tailored exemplar) design. Participants included 2465 US women ages 35-49.
Main outcome measures: PSBC as a percentage, PSBC as a frequency, worry, fear and mammography intentions.
Results: The intervention resulted in significant reductions in PSBC as a percentage for women in both strata and significant increases in worry and fear for women in the upper risk stratum. Of the possible mediators examined, only PSBC as a percentage was a consistent mediator of the effect of the intervention on mammography intentions.
Conclusion: The results provide insight into the mechanism of action of the intervention by showing that PSBC mediated the effects of the intervention on mammography intentions.
Keywords: decision aid; fear; mammography; perceived risk; perceived susceptibility; worry.