The study objective was to assess the relative effects of 2 approaches to teaching about a clinical trial, in terms of patients' satisfaction, information understanding, and whether or not they would enter such a trial. One hundred patients receiving radiation therapy for a variety of cancer diagnoses were randomized to receive information about a hypothetical trial, either by audio tape or interactive computer program. A day later, information understanding was assessed. One week later, method satisfaction and whether respondents would enter such a trial were assessed. There were no differences in understanding or satisfaction. Members of the computer program group tended to report a more positive attitude towards trial entry (chi 2 = 4.0; 1 df; P = 0.05). Overall, refusers tended to be women with higher understanding scores. The results suggest that teaching with interactive components might not adversely affect trial accrual. Further work involving an actual trial entry decision is merited; the sex of the respondent should be controlled in designing this future work.