OBJECTIVE: To compare the efficacy of a decision-making aid with an information document from the Society of Obstetricians and Gynaecologists of Canada (SOGC) with regard to decisions about hormone replacement therapy (HRT). DESIGN: Randomized clinical trial. SETTING: Quebec city region. PARTICIPANTS: Menopausal Francophone women 45 to 69 years old. INTERVENTIONS: Subjects were given a manual and an audiocassette describing a six-step approach to making a decision about HRT. MAIN OUTCOME MEASURES: Amount of anxiety over the decision (main outcome), general knowledge of the risks and benefits of HRT, personal expectations and values concerning these risks and benefits, and women's views on HRT. RESULTS: Anxiety levels were significantly reduced in both groups, but the difference between the effectiveness of the two interventions was not significant (P = .77). Percentages of women whose general knowledge increased and of women with realistic expectations were significantly higher in the experimental group (P < .003 and P < .0001, respectively). Congruence between personal values and decisions about HRT increased significantly more in the experimental group (P < or = .003). CONCLUSION: The six-step approach to decision making was more helpful than the SOGC's information document in increasing subjects' knowledge of the risks and benefits of HRT, in creating more realistic expectations of HRT, and in increasing the congruence between subjects' personal values and their decisions on HRT.