[An innovative process for sustaining and scaling up a school-based mental health promotion and anxiety prevention...

Context Anxiety disorders are among the most prevalent psychopathologies for children and adolescents in Quebec. The prevalence of anxiety disorders is very high and has been affecting a growing number of young people for the past 10 years. It is possible to observe an increased number of anxiety prevention programs for young people around the world. However, some authors point out that they are rarely faithfully implemented, sustained, and scaled up in several schools. Based on implementation science, this HORS-PISTE program was developed to address these important issues by preventing anxiety in Quebec high school students. Implemented in more than 100 schools, the program is now part of Action 4.3 (Promote the deployment of the HORS-PISTE program) of the new interdepartmental Action Plan on Mental Health of the Government of Quebec (2022). Purpose This article aims to describe how the Knowledge-to-Action (KTA) framework, derived of implementation science, was used to design, implement, sustain, evaluate, and scale up the HORS-PISTE program. This framework proposes a cyclical process in seven phases. Method A multi-method and multi-stakeholder approach was conducted with a grant from the Public Health Agency of Canada's Mental Health Promotion Innovation Fund, which has been supporting 20 innovative projects across Canada since 2019. It includes a pre-post evaluation protocol consisting of validated questionnaires, surveys (administered to students, parents, and teachers), semi-structured logbooks completed by program facilitators and implementation review meetings in each school. The different cycles of the program development, implementation and evaluation are discussed through the KTA framework phases. Results From 2017 to 2021, this methodology made it possible to evaluate and readjust the program each year to promote its adaptation and prepare its scaling up. This article highlights the data collected and analyzed in relation to the seven phases of the KTA framework. Conclusion This article demonstrates how implementation science can support designers of anxiety prevention programs who are concerned by scaling up and sustaining their programs. Issues in combining the scientific rigor of evaluation with the reality of the field are also raised.