Variations in Unrealistic Optimism between Acceptors and Decliners of Early Phase Cancer Trials

Research has found that patient-subjects in early phase cancer trials exhibit unrealistic optimism regarding the risks and possible benefits of trial participation. Unrealistic optimism is associated with therapeutic misconception and failures to appreciate research-related information. This is the first study to assess whether those who decline to participate in these trials also exhibit unrealistic optimism. It is also the first study to assess whether there are significant differences in appreciation of research-related risks/benefits and therapeutic misconception between these two groups. We approached 261 patients at two academic medical centers who were offered enrollment in a Phase I, II, or I/II cancer trial (between 2012 and 2016). Two hundred thirty-three patients agreed to enroll in an early phase cancer trial, 171 of whom agreed to be interviewed for the study. Twenty-eight patients declined the offer to enroll, 15 of whom agreed to be interviewed for the study. Subjects participated in a structured face-to-face interview with a research associate trained to administer the study questionnaires. Acceptors demonstrated a significantly higher level of unrealistic optimism than decliners (p <.05). Decliners had significantly less therapeutic misconception than acceptors (3.37 [SD = 0.85] vs. 3.79 [SD = 0.77], p =.042). There was a significant difference on one of the appreciation questions between acceptors and decliners (p =.009). Comparative assessment of acceptors and decliners to early phase cancer trials casts light on whether unrealistic optimism is consequential for the decision to participate in these trials. The different levels of unrealistic optimism exhibited by these groups suggest that it may be a factor that affects the decision to participate.