Process evaluation of a sport-for-health intervention to prevent smoking amongst primary school children: SmokeFree Sports

Background: SmokeFree Sports (SFS) was a multi-component sport-for-health intervention aiming at preventing smoking among nine to ten year old primary school children from North West England. The purpose of this study was to evaluate the process and implementation of SFS, examining intervention reach, dose, fidelity, acceptability and sustainability, in order to understand the feasibility and challenges of delivering such interventions and inform interpretations of intervention effectiveness.  Methods: Process measures included: booking logs, 18 focus groups with children (n=95), semi-structured interviews with teachers (n=20) and SFS coaches (n=7), intervention evaluation questionnaires (completed by children, n=1097; teachers, n=50), as well direct observations (by researchers, n=50 observations) and self-evaluations (completed by teachers, n=125) of intervention delivery (e.g. length of sessions, implementation of activities as intended, children's engagement and barriers). Descriptive statistics and thematic analysis were applied to quantitative and qualitative data, respectively.  Results: Overall, SFS reached 30.8% of eligible schools, with 1073 children participating in the intervention (across 32 schools). Thirty-one schools completed the intervention in full. Thirty-three teachers (55% female) and 11 SFS coaches (82% male) attended a bespoke SFS training workshop. Disparities in intervention duration (range=126 to 201 days), uptake (only 25% of classes received optional intervention components in full), and the extent to which core (mean fidelity score of coaching sessions=58%) and optional components (no adaptions made=51% of sessions) were delivered as intended, were apparent. Barriers to intervention delivery included the school setting and children's behaviour and knowledge. SFS was viewed positively (85% and 82% of children and teachers, respectively, rated SFS five out of five) and recommendations to increase school engagement were provided.  Conclusion: SFS was considered acceptable to children, teachers and coaches. Nevertheless, efforts to enhance intervention reach (at the school level), teachers' engagement and sustainability must be considered. Variations in dose and fidelity likely reflect challenges associated with complex intervention delivery within school settings and thus a flexible design may be necessary. This study adds to the limited scientific evidence base surrounding sport-for-health interventions and their implementation, and suggests that such interventions offer a promising tool for engaging children in activities which promote their health