Evaluating multiple innovative methods of recording injecting drug use episode data among people who inject drugs in Melbourne, Australia: The In-The-Moment-Expanded Pilot study

Introduction New and innovative data collection techniques allow for more detailed understanding about the contexts of individual injecting drug use episodes. With the In-The-Moment-Expanded (ITM-Ex) study, we assessed multiple novel data collection techniques to inform public health methodologies and harm reduction interventions, particularly future drug overdose detection devices. Methods Over a 29-day study period, 50 people who inject drugs were provided with an activity tracker and smart phone. ITM-Ex produced three data sources: 1) ecological momentary assessment (EMA) questionnaires completed after every injecting episode, 2) heart rate data collected via the activity tracker, and 3) return of two previously used needles/syringes for drug residue testing. Results Forty-five participants (90%) completed endline; most (n=40, 80%) retained both the study phone and activity tracker. Participants completed 1,161 EMA questionnaires (mean: 25). We estimate EMA questionnaires accounted for ≥93% of all injecting episodes. Participants wore activity trackers across an estimated 83% of all study days, or 60% of total possible hours. Of a possible 100 returned needles/syringes, participants returned 79 for drug residue testing. We successfully linked 80% (n=930) EMA questionnaires with associated heart rate data. We linked 48/79 (61%) needle/syringe samples with an associated EMA questionnaire. Discussion ITM-Ex demonstrated the effectiveness of our data collection methods both in unison and combined with each other, providing methodological guidance to other public health research. Our EMA methods proved particularly successful at capturing data, which, combined with other data, created a highly detailed dataset of unique injecting drug use episodes.