摘要：Purpose To examine adolescent experiences and perspectives of the GoActive intervention (ISRCTN31583496) using mixed methods process evaluation to determine satisfaction with intervention components and interpret adolescents’ experiences of the intervention process in order to provide insights for future intervention design. Methods Participants ( n = 1542; 13.2 ± 0.4 years, mean ± SD) provided questionnaire data at baseline (shyness, activity level) and post-intervention (intervention acceptability, satisfaction with components). Between-group differences (boys vs. girls and shy/inactive vs. others) were tested with linear regression models, accounting for school clustering. Data from 16 individual interviews (shy/inactive) and 11 focus groups with 48 participants (mean = 4; range 2–7) were thematically coded. Qualitative and quantitative data were merged in an integrative mixed methods convergence matrix, which denoted convergence and dissonance across datasets. Results Effect sizes for quantitative results were small and may not represent substantial between-group differences. Boys ( vs. girls) preferred class-based sessions ( β = 0.2, 95% confidence interval (CI): 0.1–0.3); qualitative data suggested that this was because boys preferred competition, which was supported quantitatively ( β = 0.2, 95%CI: 0.1–0.3). Shy/inactive students did not enjoy the competition ( β = –0.3, 95%CI: –0.5 to –0.1). Boys enjoyed trying new activities more ( β = 0.1, 95%CI: 0.1–0.2); qualitative data indicated a desire to try new activities across all subgroups but identified barriers to choosing unfamiliar activities with self-imposed choice restriction leading to boredom. Qualitative data highlighted critique of mentorship; adolescents liked the idea, but older mentors did not meet expectations. Conclusion We interpreted adolescent perspectives of intervention components and implementation to provide insights into future complex interventions aimed at increasing young people's physical activity in school-based settings. The intervention component mentorship was liked in principle, but implementation issues undesirably impacted satisfaction; competition was disliked by girls and shy/inactive students. The results highlight the importance of considering gender differences in preference of competition and extensive mentorship training.
