Abstract / Summary
Abstract Background Given increased interest and investment in adolescent health, it is critical that research is designed and executed in a manner that respects participant autonomy and encourages meaningful engagement. Consent procedures are likely central to this aim but are underexplored empirically. Methods We conducted a pre-registered complementary mixed-methods investigation evaluating the impact of consent procedures on adolescent research participation. The quantitative strand was a parallel-group randomised controlled trial (RCT) wherein participants completed an online survey about health, wellbeing, and risk behaviours under one of five consent procedures. Outcomes were consent rates (initial and withdrawal), completion rates (survey- and item-level), and responses on measures of varying sensitivity. The qualitative strand was a focus group study, conducted in line with Constructivist Grounded Theory methodology, exploring adolescents’ views on research consent. Results Three thousand seven hundred twenty adolescents participated in the RCT and 46 in the focus groups. Qualitative findings showed that adolescents valued choice and control in research, which they felt could increase comfort and openness, particularly within research on sensitive topics. Participants suggested that consent procedures could influence adolescents’ decisions to participate in research, the information they share, and longer-term retention. These insights, however, were not fully reflected in quantitative findings. Initial consent (92.7–95.4%) did not significantly differ across arms, and in procedures with repeated consent prompts, approximately 6–8% of participants withdrew consent at least once. Completion varied and was highest in the anonymous procedure (83.3% survey-level completion, mean item-level completion = 49.7/54 items). There were no significant differences in how participants responded (in terms of scores) for any measure. Conclusions This trial provides empirical evidence that consent procedures differentially influence adolescents’ engagement with health research. Enhanced autonomy was associated with reduced completion, but whilst this may appear detrimental when judged solely in terms of completion rates, it also represents a more ethically robust form of participation. Importantly, differences in withdrawal did not appear to alter how the remaining students responded to the questionnaire items, which may indicate that allowing greater control over participation may support more authentic engagement and disclosure. These findings suggest that consent procedures should be tailored to study aims and context, balancing scientific priorities with adolescents’ rights to autonomy.