Adaptation, Student Participation and Gradual Withdrawal by Researchers as Sustainability Strategies in the High School-Based Young and Active Intervention: School Coordinators' Perspectives.

Ensuring the sustainability of school-based public health intervention activities remains a challenge. The Young and Active (Y&A) intervention used peer-led workshops to promote movement and strengthen students' sense of community in 16 Danish high schools. Peer mentors inspired first-year students to implement movement activities. To support sustainability, we applied a three-year stepwise implementation strategy using university students as peer mentors in year 1 and senior high school students in the following two years. This study explores the sustainability potential of Y&A, focusing on school coordinators' reflections on the intervention's fit to their schools and the student-driven approach, and we assess the three-step implementation strategy. The study is based on telephone interviews with coordinators (n = 7) from schools that participated in all three years and participant observations of four workshops (a total of approximately 250 participating students). Results were generated through an abductive analysis. Seven schools continued the intervention throughout the three years and adapted it to fit their priorities. The student-driven approach was perceived to be valuable, but few student-driven activities were initiated. Teacher support seemed crucial to support students in starting up activities and acting as peer mentors in workshops. The three-step implementation strategy proved valuable due to the peer-approach and the possibility of gradual adaptation. In future similar initiatives, it is important to address how the adequate staff support of students can be facilitated.