Sampling and recruitment of participants

Participants were selected based on a combination of sampling methods that aimed to reach a diversified and comprehensive sample of patients with a broad set of perceptions and experiences regarding access to pain clinic services [30–32]. First, a convenience sampling approach was used by sending an email invitation through patients and academic-based organizations’ contact lists (i.e., university, Arthritis Society, Quebec Association of Chronic Pain) and posting an advertisement in pain clinic waiting rooms. Second, the snowball sampling method was used by inviting participants to suggest any other potential participants (e.g. relatives, colleagues). Lastly, a purposive sampling approach was used by asking pain clinic nurses and physicians to share the invitation to participate in the study to patients that fit a specific profile based on certain sociodemographic (age, gender), contextual (wait time duration) and clinical criteria (diagnosis). This method allowed to target participants with profiles underrepresented in the sample until then (e.g., men patients or patients with osteoarthritis).

Potential participants interested in the study contacted the research team by email or telephone; then, the objectives of the study were explained, the inclusion criteria were verified, and the interview scheduled. With an initial targeted sample of approximately 25 to 30 participants, recruitment continued until data saturation was reached, whereby no new theme stemmed from the interviews and the density and depth of the data were considered sufficient to answer the research objective [30, 31, 33].