Sexual and reproductive health (SRH) for adolescents is a global public health concern. Access to SRH information and services regarding contraception is necessary, particularly in underserved regions, such as the French overseas territories of Reunion Island and Guadeloupe, where indicators for teenage pregnancy and abortion are significantly high. This study protocol describes the methodology to be used to assess the feasibility of a peer-led contraception education programme for high school students using social media.

A multicentre, exploratory sequential mixed-methods with a pre-post design, prospective study is being conducted in Guadeloupe and on Reunion Island. The qualitative component started on 31 May 2025, and the study will continue until 30 June 2026. Participants will be aged 15 to 19 years and will attend high school. In Phase 1, focus groups will explore the adolescents’ perceptions of peer influencers in contraceptive education and their suggestions for organising a prevention programme on social media. These findings will directly inform the intervention in Phase 3. At this stage of this phase, peer influencers will also be identified. Phase 2 will train selected peer educators in SHR, digital content creation to prepare them for intervention design and delivery. Phase 3 consists of the co-construction, implementation and evaluation of the intervention. Outcomes will include feasibility, acceptability, adoption, fidelity and exploratory effectiveness. The primary outcome will be peer engagement defined as the completion of at least 70% of the planned educational tasks.

This study has received ethical approval from the Comité de Protection des Personnes under RIPH3 (ID-RCB: 2025-A00358-41) and will follow the French ethical standards for low-intervention research. Results will be shared in scientific publications and with participating schools.

NCT06943209.

The introduction of fentanyl and its analogues in the illicit drug supply has prompted greater emphasis on refining clinical treatment protocols to ensure sustained retention in opioid agonist treatment (OAT). Take-home dosing may lessen the treatment burden on clients and thus reduce the risk of treatment discontinuation. The evidence base supporting the use of take-home dosing, including the optimal duration of dispensations, is, however, limited. The objective of this study is to determine the comparative effectiveness of alternative take-home dosing schedules, as observed in clinical practice in British Columbia, Canada from 2010 to 2022.

We propose to emulate a target trial with a population-level retrospective study of individuals initiating methadone or buprenorphine/naloxone between 1 January 2010 and 31 December 2022 who are 18 years of age or older and not currently incarcerated or pregnant with no history of cancer or palliative care. Our study will draw on nine linked health administrative databases from British Columbia and will evaluate take-home doses of 2–5 days, 6 days or >6 days compared with continuous daily dosing. The primary outcomes include OAT discontinuation and all-cause mortality on treatment. A causal per-protocol analysis is proposed with longitudinal matching and inverse probability of censoring weighting approaches to adjust for time-fixed and time-varying confounding. A range of sensitivity analyses will be executed to determine the robustness of results.

The protocol, cohort creation and analysis plan have been classified and approved as a quality improvement initiative by Providence Health Care Research Ethics Board and the Simon Fraser University Office of Research Ethics. Results will be disseminated and shared with local advocacy groups and decision-makers, developers of national and international clinical guidelines, presented at national and international conferences and published in peer-reviewed journals electronically and in print.

Opioid agonist treatment (OAT) prescribing patterns have shifted in recent years in British Columbia (BC), Canada due to the increasingly toxic unregulated drug supply. Experimental evidence to support guidelines on the effectiveness of maintaining clients at different maintenance dosage levels is incomplete and outdated for the fentanyl era. Our objective is to assess the risk of treatment discontinuation and mortality among individuals receiving different maintenance dosage strategies for OAT with methadone, buprenorphine/naloxone or slow-release oral morphine (SROM) at the population level in BC, Canada.

We propose a retrospective population-level study of BC residents initiating OAT on methadone, buprenorphine/naloxone or SROM between 1 January 2010 and 31 December 2022 who were ≥18 years of age with no known pregnancy, no history of cancer diagnosis or receiving palliative care and not currently incarcerated. Our study will employ health administrative databases linked at the individual level to emulate a target trial per OAT type where individuals will be assigned to discrete maintenance dosing strategies, according to the full range observed in BC during the study period. Primary outcomes include treatment discontinuation and all-cause mortality. To determine the effectiveness of alternative maintenance doses, we will emulate a ‘per-protocol’ trial using a clone-censor-weight approach to adjust for measured time-dependent confounding by indication.

The protocol, cohort creation and analysis plan have been classified and approved as a quality improvement initiative by Providence Health Care Research Ethics Board and the Simon Fraser University Office of Research Ethics. All data are deidentified, securely stored and accessed in accordance with provincial privacy regulations. Results will be disseminated and shared with local advocacy groups and decision-makers, developers of national and international clinical guidelines, presented at national and international conferences and published in peer-reviewed journals electronically and in print.