CTN 342: Toronto Disparities, Overdose, and Treatment (T-DOT) Study

Study Approach

Researchers will evaluate frontline service offerings and participant health outcomes across seven community health agencies and two non CHAs that provide culturally appropriate outreach, education and advocacy, across the Toronto area. Clients at the sites are invited to participate in the study, as well as an equal number of non-SCS users who live in the surrounding areas or access services at these locations. Participants complete an interviewer administered survey about experiences at the sites across the GTA and other services within Toronto that they may access. The surveys explore topics such as socio demographics, social determinants of health, housing access, financial stability, access to resources, services the participants use at each site, their experiences with those services, physical and mental health and barriers to access. The interview and survey is repeated every six months including two incentivized check-ins, in between interviews. Participants will receive honoraria for their time. Presently, the study is funded until October of 2027. The study has been operational since 2018.

All participants in the study will be eligible to receive on-site HIV and hepatitis C point-of-care testing (POCT), both at the initial baseline visit and at consecutive follow-ups interviews. HIV and Hep C POCT is taking place at three of our partner sites. South Riverdale CHA is the first pilot site, followed by the Parkdale CHA and Sherbourne Health, both of which will be operational in May 2026. Uptake of POCT testing will be compared among participants accessing it directly at sites where it is offered compared to those that are referred to testing from interview sites that do not offer this testing. Treatment access after positive tests will also be compared between participants who opt for POCT testing compared to study participants who received diagnoses in the time period prior to the initiation of the POCT intervention.   

Through established data partnerships, the investigative team will also collect and analyse data from Toronto Paramedics Services, the Chief Coroner of Ontario, and ICES (formerly the Institute for Clinical Evaluative Sciences, a provincial repository of administratively-captured health outcomes data from Ontarians). This will allow us to measure the potential impact of the shifting service delivery and drug market landscapes in Toronto, and how the closures and limited availability of various interventions, including SCS and ‘HART’ hubs, influence morbidity, mortality, and social outcomes among study participants and population health outcomes at the neighbourhood level across Toronto. Altogether, this will inform an assessment of the effectiveness of current drug policy and service implementation approaches and provide pathways to mitigate an ongoing drug toxicity crisis and likely increases in the prevalence and incidence of infectious diseases among people who use drugs.