Feasibility and acceptability of using smartphone-based EMA to assess patterns of prescription opioid and medical cannabis use among individuals with chronic pain

Background: Intensive longitudinal studies are needed to examine the co-use of prescription opioid medication and medical cannabis and their effects on chronic pain. The current study sought to investigate the feasibility and participant compliance with a smartphone-based Ecological Momentary Assessment (EMA) data collection protocol among individuals who use multiple substances and suffer from chronic pain. Methods: A total of 46 participants (mean age = 44.8 years; 78% female; 85% Non-Hispanic White) were recruited online and completed a 30-day EMA phase where they responded to prompted surveys (four random past-hour surveys and one daily diary per day) about opioid medication use, medical cannabis use, and pain symptoms. Qualitative follow-up interviews were conducted with a subset of 10 participants. Linear and logistic regression models were used to examine baseline participant characteristics in relation to EMA compliance. Qualitative indicators of participant study experience were extracted from interviews. Results: Participants responded to an average of 70% of past-hour surveys and 92% of daily diaries. Female participants were more likely to complete all daily diaries and at least one past-hour survey per day on all 30 days, respectively (OR = 5.60, 95% CI: 1.02–30.77, p < .05; OR = 7.08, 95% CI: 1.28–39.16, p < .05). Female participants were also more likely to complete at least 75% of their prompted past-hour surveys (OR = 4.67, 95% CI: 1.00–21.69, p < .05). Interview participants reported a positive study experience overall, although some mentioned problems related to smartphone notifications, redundant questions, or being prompted when they were not feeling well. Participants also mentioned problems with reporting the amount of medical cannabis used (e.g., milliliters of vaping liquid). Conclusions: Study results demonstrate both feasibility and acceptability of using EMA methodology to examine use patterns of medical cannabis and prescription opioid medication among individuals with chronic pain.