Facilitators and Barriers to Participating in a Randomized Controlled Trial of a Psychological Therapy for Substance Use.

Research involving substance users with psychosis has high refusal and attrition rates. Understanding participants' experiences of research participation is therefore important. Twenty-two cannabis users with schizophrenia spectrum disorders were recruited. They were involved in a randomized controlled trial exploring the effectiveness of motivational interviewing plus cognitive behavioral therapy. Semistructured interviews were conducted, and their responses were analyzed using thematic analysis. Thematic analysis identified facilitators such as therapeutic benefit, knowledge about medical conditions, awareness of own drug habits, helping others, confidentiality, rapport with researchers, desiring social contact, and views of significant others. Barriers identified were cognitive challenge, amount of assessments, duration, and discussions about the past. Based on these insights, we recommend informing participants about clinical equipoise, confidentiality, and demands of the study; minimizing demands on participants; acknowledging participants' efforts; involving potential participants' significant others during recruitment; advertising research as an opportunity to help; and training researchers in building rapport.