The Social Scientific Investigation into Randomized Controlled Trial Participation in the Addictions (SIRCA) program is a series of studies that examines the individual, social, and structural dimensions of participation in addiction randomized controlled trials (RCTs) among people who use drugs. The study is comprised of both observational research on hypothetical motivations and willingness to participate in RCTs, as well as nested studies that partner with real-world addictions RCTs. By partnering with ongoing studies, this research focuses on how the life circumstances of people who use drugs are related to their RCT participation in terms of recruitment, protocol adherence, participation outcomes, and participation experiences. The studies focus on hypothetical as well as actual research scenarios, and evaluate the dimensions of RCT participation longitudinally, from pre-trial preparedness through to post-trial reflection.


The RCT Participation Study has the following objectives:

  • To explore the determinants of motivations, barriers, and willingness to participate in addiction RCTs;
  • To assess the individual, social, and structural correlates of RCT trial preparedness;
  • To explore attitudes about and experiences of addiction RCT participation; and
  • To identify determinants of protocol adherence and trial completion.


  • AIDS Care Cohort to Evaluate Exposure to Survival Services (ACCESS)
  • At-Risk Youth Study (ARYS)
  • Canadian Research Initiative in Substance Misuse (CRISM)
  • The Comparing Treatments for HIV-Positive Opioid and Alcohol Users in an Integrated Care Effectiveness Study (CHOICES), a study of the US National Institute of Drug Abuse Clinical Trials Network
  • The Impact of Alternative Social Assistance on Drug Related Harm (TASA Cheque Issue Study)
  • Vancouver Injection Drug Users Study (VIDUS)


  • Canadian Institutes of Health Research (CIHR)


To learn more about SIRCA, please contact us.

Lindsey Richardson, Research Scientist
Phone: (604) 558-6677
Email: [email protected]

BC Centre on Substance Use

400-1045 Howe St, Vancouver, BC V6Z 2A9

E: [email protected] | T: (778) 945-7616 | F: (604) 428-5183

24/7 Addiction Clinician Support Line: (778) 945-7619

Online Addiction Medicine Diploma: [email protected].

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