Supporting Trial Participation in People with the Huntington's Gene: A Patient-Centered, Theory-Guided Survey of Barriers and Enablers.

Background: Under-recruitment regularly impedes clinical trials, leading to wasted resources and opportunity costs. Methods for designing trial participation strategies rarely consider behavior change theory.

Objective: Informed by the Theoretical Domains Framework, we identified factors important to participating in Huntington's disease research and provide examples of how such a theory-informed approach can make specific suggestions about how to design targeted recruitment strategies.

Methods: We identified a range of trial participation barriers and enablers based on interviews of key informants and implemented an online survey of members of the Huntington's disease community, asking them to rate the extent to which different factors would affect likelihood to participate in a generic Huntington's disease trial.

Results: From 4,195 members, we received 323 responses and 243 completed surveys (323/4,195 or 8% participation, 243/323 or 75% completion). Respondents endorsed 9 barriers and 23 enablers relevant to trial participation. Most frequently endorsed barriers were travel to the study site (69%), worry about unknown side effects (65%), trial documents being difficult to understand (64%), and participation affecting other activities (49%). Enablers included optimism about likelihood of trial participation leading to a cure (98%), helping others (98%), contributing to science (97%), and having helpful people available to help with the participation decision (89%).

Conclusion: Our theory-informed survey to identify barriers to and enablers of Huntington's disease trial participation identified 32 factors, from 13 theoretical domains relevant to trial participation, and suggests effective approaches for improving trial participation and patient experience.