Design, setting and participants

This qualitative study followed a constructivist grounded theory approach [35, 36], selected for its ability to understand how and why patient-centered experiences were relevant in iOAT. In-depth interviews were conducted with clients receiving iOAT at Providence Health Care’s Crosstown Clinic (Vancouver, Canada). This Clinic was initially implemented as the purpose-built site for the NAOMI (2005–2008) [17] and SALOME (2011–2014) [16] clinical trials that tested the effectiveness of injectable diacetylmorphine and hydromorphone treatments. At the time of collecting data for the present study, Crosstown Clinic remained the first and only iOAT program in North America, delivering treatment to approximately 130 people with opioid use disorder [16, 37]. In this setting, clients are prescribed up to three doses per day and self-administer medications under the observation of Registered Nurses [38]. During the present study, Physicians were the primary prescribers of iOAT and participants had access to an interdisciplinary care team of Health Professionals (Social Workers, Psychiatrist, Nurse Practitioner, a Nutritionist).

Consistent with the grounded theory approach, purposeful and theoretical sampling of Crosstown Clinic clients evolved iteratively with data analysis and continued until reaching theoretical sensitivity (i.e., no remaining questions about the interrelationship between core concepts) [36]. This occurred after conducting 30 in-depth interviews with 14 women and 16 men (Table 1).

Select self-report participant characteristics at initial iOAT entry

Data shown are mean ± standard deviation; N (%)

^aAboriginal ancestry includes participants who self-identified as Inuit, Metis, or First Nations.

^bMAP Physical and Psychological health scores range from 0 to 40 with higher scores indicating poorer health.

^cEQ5D (Euroquol) with Canadian weights scores range from 0 to 1; higher scores are indicative of better health status.

^dBased on administrative prescription records data from 1995 to 2012.