Understanding patient expectations in early-phase clinical trials

Abstract

6543 Background: Participants in early-phase clinical trials have reported high expectations of benefit from their participation. There is concern that participants misunderstand the trials to which they have consented. Such concerns are based on assumptions about what patients mean when they respond to questions about likelihood of benefit. In this study, we explored some of these assumptions. Methods: Participants were 27 women and 18 men in phase 1 or 2 oncology trials and randomized to 1 of 3 interview protocols corresponding to 3 target questions about likelihood of benefit: frequency-type (‘Out of 100 patients who participate in this study, how many do you expect will have their cancer controlled as a result of the experimental therapy?‘); belief-type (‘How confident are you that the experimental therapy will control your cancer?‘); and vague (‘What is the chance that the experimental therapy will control cancer?‘). In semistructured interviews, we queried participants about how they understood and answered the target question. Each participant then answered and discussed one of the other target questions. Results: Participants tended to provide higher expectations in response to the belief-type question (median, 80) than in response to the frequency-type or vague questions (medians, 50) (P=.02). Only 7 (16%) participants said their answers were based on what they were told during the consent process. The most common justifications for responses involved positive attitude (n=27 [60%]) and references to physical health (n=23 [51%]). References to positive attitude were most common among participants with high (>70%) expectations of benefit (n=11 [85%]) and least common among those with low (<50%) expectations of benefit (n=3 [27%]) (P=.04). Conclusions: We identified two factors that should be considered when determining whether high expectations of benefit are signs of misunderstanding. First, participants report different expectations of benefit depending on how the question is asked. Second, the justifications participants give for their answers suggest that many participants use their responses to express hope rather than to describe their understanding of the clinical trial. These findings should inform methods for evaluating the quality of informed consent in early-phase trials. No significant financial relationships to disclose.