My Life - I Decide: A Health Promoting School Intervention

Background Low mental health and well-being increase the risk of not completing secondary education. Almost every tenth young person in Denmark reports low mental health and well-being, and from 1984-2018, mental health, well-being, and self-reported health have decreased among 15-year-olds. Data from the Danish Health Behavior in School Children Survey 2018 reported that among 15-year-old students, 11% of boys and 20% of girls had low positive mental health measured by the Warwick-Edinburgh Mental Well-Being Scale. Altogether, these factors call for mental health and well-being interventions among young people, as indicated by the priority areas posed in the common Health Agreement between the Capital Region, local communities, and general practice in Denmark. In Denmark, students who are not ready to attend secondary education have the option to attend 10th grade before embarking on the next steps in life. However, almost half of 10th grade students have been found to be tired of school, and every fourth student felt pressured by the amount of work in school. In addition, students attending municipal 10th grade schools report lower professional self-confidence compared to students at voluntary boarding schools (efterskole), making municipal 10th grade students in need of support to ensure educational readiness and attainment to progress into secondary education. Improving health among youth has been shown to have positive effects on educational attainment. Positive mental health among adolescents has been associated with educational attainment in adulthood. Health literacy can be seen as an indicator of later health behavior among youth, as higher health literacy scores among Vocational Education and Training students are associated with lower odds of unhealthy behaviors. Mental health promotion initiatives show strong evidence for using the school setting to strengthen positive mental health, including self-efficacy, mental well-being, and social and emotional skills. Targeting 10th grade students therefore has the potential to increase both positive mental health and educational attainment and progression into secondary education. Students attending 10th grade expect personal and social development in the form of new life-skills, maturity, extroversion, inclusive class communities, and a varied school day with new forms of learning, activities, and movement. This setting therefore presents an ideal opportunity for health promotion initiatives. The Health Promoting Schools (HPS) framework further advocates for using a whole-school approach, ensuring that different socioecological levels are targeted. Nonetheless, implementing whole-school interventions like the HPS remains challenging, often due to tokenistic rather than authentic implementation. Increasing authentic implementation requires interventions sensitive to school contexts, ensuring that teachers experience interventions as acceptable and feasible. However, knowledge remains limited on how and why school-based interventions work or do not work, underlining the need for research investigating both processes and outcomes. Aim and Objectives The overall aim of the My Life project is to test whether the comprehensive My Life intervention can be recommended for implementation on a national scale. The specific objectives of the project are to: A) Test the effectiveness of the intervention in a controlled, waiting-list design at the student level. B) Test impacts at the system level. C) Investigate mechanisms of change at both student and system levels, and examine implementation processes. The My Life Intervention My Life - I Decide is a school-based health promotion intervention developed through a practice-research partnership with Vallensbæk local community, Steno Diabetes Center Copenhagen, and the Intersectoral Prevention Laboratory. The intervention is inspired by the Health Promoting Schools (HPS) approach and is implemented over 1.5 years in 10th grade. It consists of four main components: (1) Preparation, (2) Planning, (3) Health Education Program, and (4) Anchoring. Preparation: A formal collaboration agreement between schools and local community health departments clarifies roles, resources, and responsibilities. A detailed intervention manual supports implementation. Planning: Includes a two-day training program for local community health consultants, establishment of a peer support network, start-up meetings with teachers, and joint planning of the education program tailored to local conditions. Health Education Program: Delivered by trained local community health consultants during the first school semester (11-13 weeks). The program consists of 15 sessions (60 minutes each) covering physical and mental health topics such as nicotine, sleep, physical activity, social media, and well-being. Sessions emphasize active participation, group work, and outdoor learning, involving both health consultants and teachers. Anchoring: After the program, schools hold a Health Promoting Schools meeting with teachers, health consultants, and management to evaluate and plan health-promoting actions, including school policies, student initiatives, and structural changes. Design and Power The effectiveness trial uses a pragmatic controlled waiting-list design, with classes as the assigning unit. Pragmatic trials, also called effectiveness or real-world trials, are designed to determine the effects of interventions under usual conditions, as opposed to the highly controlled conditions of classical efficacy trials. Classes will either be assigned to intervention during the school year 2025/2026 or 2026/2027. During the set-up phase, feasibility of randomization of schools or classes will be established. This aligns with guidelines recommending non-randomized designs when practical circumstances do not allow highly controlled studies. Matching will be considered based on school comparability in terms of student numbers and socio-economic status, maintaining a pragmatic approach and seeking equal distribution across intervention (early starters) and controls (later starters). Eight schools with a total of 26 classes and approximately 500 students will participate. Outcomes and Measurements Student-level outcomes will be assessed via online surveys at three time points: Baseline (September 2025): 1-2 weeks after class formation, prior to the health education and anchoring components. Mid-intervention (Time 1, T1) (Nov-Dec 2025): Immediately after completion of the health education program. Follow-up (Time 2, T2) (March-April 2026): 7-8 months after baseline after full intervention implementation. Data will be collected simultaneously in intervention and control schools. Surveys will be administered during a 45-minute class session under exam-like conditions. Students will complete questionnaires via REDCap using headphones and guided video instructions. Investigators and trained interns will supervise to ensure standardized conditions and provide technical support. System-level impacts will be assessed using the validated Health Promoting School Practices and Capacity (HPS-Q) tool. The tool includes 24 items across seven subdimensions: school policies, ethos, collaboration/involvement, school practice, quality of delivery, resources, and health services. Items were adapted to fit the My Life intervention. Respondent characteristics such as gender, age, teaching subjects, and work experience will also be collected. Baseline: April-August 2025 (with an additional round in August for newly employed staff). Follow-up: April-May 2026. All staff working with 10th grade students will be invited to complete an online survey. Qualitative data will be collected to capture intended and unintended system-level effects: Semi-structured interviews (n=16) with teachers, health consultants, and school/local community managers in May-June 2026. Realist Ripple Effects Mapping (RREM) workshop in May-June 2026 with teachers, school management, and health consultants to trace causal pathways and map unanticipated outcomes. If not feasible, short structured interviews with school and local community coordinators will be conducted instead. Process Evaluation The process evaluation will examine: Implementation of the intervention across diverse school settings (fidelity, reach, acceptability). Mechanisms triggered at the student level during and after implementation. Mechanisms triggered at the system level for longer-term impact. A realist-informed approach will be applied, combining deductive, inductive, and theory-driven analyses to explore how context and mechanisms produce outcomes. Cross-Sectoral Collaboration and Organization Collaborators include Steno Diabetes Center Copenhagen (SDCC, principal investigator), the Intersectoral Prevention Laboratory (TIPL, co-investigator), and Vallensbæk local community. Vallensbæk, HS, and a daily project coordinator are responsible for practice-related parts, including intervention implementation, consultant training, and coordination between local communities. SDCC is responsible for research and evaluation activities, in close dialogue with practice. A steering committee, consisting of representatives from TIPL, SDCC, HS, local communities, and 10th grade schools, will follow activities, ensure resource allocation and anchoring, and contribute to dissemination. An operating project group consisting of HS and the municipal project coordinator will coordinate intervention and research progress. A research coordination group will meet regularly to ensure progress and quality of research. Dissemination of Knowledge Knowledge created will be disseminated to relevant stakeholders, including schools, local communities, and researchers. An external communication plan will ensure representation of student perspectives. Dissemination channels include: Scientific journals The Danish Healthy Cities Network The collaboration of 10 Danish local communities National and international conferences Center for Prevention in Practice (Local Government Denmark) Teacher and supervisor networks within the school system The Intersectoral Prevention Laboratory annual network meeting Local newspapers and social media channels Bilateral meetings with relevant organizations and partners Legal, Ethical, and Regulatory Demands The effectiveness trial will be registered in ClinicalTrials.gov. All data will be collected, processed, and securely stored in accordance with the Danish Data Protection Agency and adhere to the Danish Code of Conduct for Research Integrity. The Capital Region of Denmark and SDCC will host all data.