Reaching people with opioid use disorder who are unhoused or on the verge of losing housing remains one of the most stubborn gaps in addiction medicine. Fixed-site clinics impose barriers — transportation, identification, stigma, appointment scheduling — that effectively exclude the populations at greatest overdose risk. A mobile delivery model that eliminates those barriers offers a potentially scalable alternative, and this multisite evaluation provides some of the first longitudinal data on whether such programs can operate at meaningful scale.
The Community Care in Reach model, operating across six Massachusetts programs between January 2022 and June 2024, logged 17,887 harm reduction encounters and 16,117 clinical encounters serving 4,645 individuals. Of the 1,227 people who initiated buprenorphine — a first-line medication for opioid use disorder — 15% remained in treatment at the 180-day mark. Qualitative and quantitative methods were applied within the RE-AIM implementation science framework to assess reach, effectiveness, adoption, implementation, and maintenance across partner organizations.
The 15% buprenorphine retention figure at six months warrants careful interpretation. Studies of standard clinic-based buprenorphine treatment typically report 30-day retention rates around 50–60%, with six-month rates frequently falling below 40% even in optimal settings. For a population that is unhoused and historically disengaged from care, 15% at 180 days may reflect genuine success in initiating treatment among people who would otherwise receive none — or it may signal that mobile models still struggle with the continuity challenge. The evaluation is descriptive rather than comparative, meaning there is no matched control group to establish counterfactual outcomes. The reliance on multi-organizational data also introduced measurement heterogeneity, acknowledged by the authors. Still, the sheer volume of encounters — roughly 34,000 across 30 months — establishes that mobile addiction services can achieve operational scale. For public health planners, this represents incrementally important evidence that low-barrier mobile models are logistically viable, even as questions about long-term efficacy and cost-effectiveness remain open.