Upscaling implementation of The Illicit Project UK

Background Substance use among young people in the UK remains a public health concern, with recent increases in some drug types and associated harms. Early onset of substance use is linked to greater risk of lifetime harm and dependence and school-based prevention contributes to national drug strategy outcomes. However, few programmes demonstrate both effectiveness and scalability. The Illicit Project (TIP) is an Australian psychoeducational skills-based substance use prevention programme targeting older school students. It is delivered online with classroom session to reinforce learning. TIP was shown to be effective in a previous Australian RCT. In RDIS Phase 2, TIP was successfully adapted to UK contexts (renamed TIP-UK) and delivered in 15 schools, demonstrating feasibility and acceptability. Aims This study aims to upscale TIP-UK delivery to at least 48 secondary schools in North West England and Scotland, evaluate implementation and short-term outcomes, and pilot methods for a future larger-scale trial. Additional aims are to assess the feasibility of integrating TIP-UK with existing commissioned young people’s drug and alcohol services to support long-term sustainability. Methods Design: A three-arm pilot cluster RCT study conducted with students aged 15-18 attending mainstream secondary schools. Intervention: (i) TIP-UK, (ii) TIP-UK+ (TIP-UK with integration with local commissioned drug/alcohol services), delivered in place of statutory drugs education. Comparator: Education as normal, typically RSHE/Health and Wellbeing lessons. Sample: 48 randomly allocated schools, stratified by socioeconomic status (16 per arm, minimum 100 pupils per school). Recruitment is supported by local authorities. Outcome measures: Collected at baseline and 3 months follow up. Primary outcomes: Use of substances (alcohol cannabis, cocaine, ketamine, MDMA, nitrous oxide, tobacco, nicotine vaping). Secondary outcomes: drug literacy, drug knowledge, mental wellbeing, and quality of life. Data will be analysed using two-level random intercept models adjusted for clustering and covariates to simulate a full trial analysis. An embedded process evaluation will assess fidelity, acceptability, contextual factors, and delivery costs. Qualitative work in 18 schools (6 per arm) will involve interviews with staff, pupils, and service providers. A micro-costing analysis will estimate local and national roll-out costs. Timelines The 14-month study commences in February 2026 (M0). School recruitment runs in M1-4, intervention delivery in M7-9, and assessment of post-intervention outcomes and implementation during M10-12. A decision on progress will be made in M14. We will convene quarterly advisory group meetings, including dedicated groups with young people and professionals, to steer the work. Impact and Dissemination Findings will inform the scalability and sustainability of TIP-UK, including its potential alignment with existing national drug prevention infrastructure. Evidence generated will guide decisions on progression to a full impact trial and provide policymakers with costs for local and national roll-out. Dissemination will include peer-reviewed publications, conference presentations, policy briefings, and youth-friendly outputs co-created with the Young Person Advisory Group. If proven effective in a full trial, TIP-UK could be offered to UK schools free of charge, with delivery costs potentially met through integration into commissioned services.