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Reach, Recruitment, Dose, and Intervention Fidelity of the GoActive School-Based Physical Activity Intervention in the UK: A Mixed-Methods Process Evaluation.

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Croxson, Caroline HD 
Foubister, Campbell 
Brown, Helen Elizabeth  ORCID logo


School-based multi-component physical activity (PA) promotion is advocated; however, research has indicated that a multi-component approach may not always be effective at increasing adolescent PA. Evaluation of the GoActive 12-week multi-component school-based intervention showed no effect on adolescent PA. A mixed-methods process evaluation was embedded to facilitate greater understanding of the results, to elicit subgroup perceptions, and to provide insight into contextual factors influencing intervention implementation. This paper presents the reach, recruitment, dose, and fidelity of GoActive, and identifies challenges to implementation. The process evaluation employed questionnaires (1543 Year 9s), individual interviews (16 Year 9s; 7 facilitators; 9 contact teachers), focus groups (48 Year 9s; 58 mentors), alongside GoActive website analytics and researcher observations. GoActive sessions reached 39.4% of Year 9s. Intervention satisfaction was relatively high for mentors (87.3%) and facilitators (85.7%), but lower for Year 9s (59.5%) and teachers (50%). Intervention fidelity was mixed within and between schools. Mentorship was the most implemented component. Factors potentially contributing to low implementation included ambiguity of the roles subgroups played within intervention delivery, Year 9 engagement, institutional support, and further school-level constraints. Multiple challenges and varying contextual considerations hindered the implementation of GoActive in multiple school sites. Methods to overcome contextual challenges to implementation warrant in-depth consideration and innovative approaches.



fidelity, mixed-methods, physical activity, process evaluation, school-based intervention

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Children (Basel)

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Medical Research Council (MC_UU_12015/7)
Medical Research Council (MR/K023187/1)
Department of Health (via National Institute for Health Research (NIHR)) (114687)
Wellcome Trust (087636/Z/08/Z)
Economic and Social Research Council (ES/G007462/1)
MRC (MC_UU_00006/5)
This study is funded by the National Institute for Health Research (NIHR) Public Health Research Programme (13/90/18). The views expressed are those of the authors and not necessarily those of the NIHR or the Department of Health and Social Care UK. This work was additionally supported by the Medical Research Council (Unit Programme number MC_UU_12015/7) and was undertaken under the auspices of the Centre for Diet and Activity Research (CEDAR), a UKCRC Public Health Research Centre of Excellence.