Study Protocol on Rapid Measurement of Novel Harm Reduction Housing on HIV Risk, Treatment Uptake, Drug Use, and Supply.

Harm reduction services save lives and facilitate treatment uptake for people who are unhoused and use drugs. It is unknown whether provision of harm reduction services within a transitional housing environment affects treatment uptake, drug supply, or drug using behaviors. This study focused on mitigation of the impacts of mass relocation and uptake of services by residents of harm reduction housing (HRH) to generate novel insights on individual drug use, social cohesion, collective efficacy, and health outcomes resulting from HRH. We used a mixed-methods study leveraging our prior Rapid Assessment of Consumer Knowledge findings and ongoing drug checking capacity to gather data on response to rapid rehousing in Boston's "Mass and Cass" neighborhood. First, we developed an inventory of harm reduction services offered and accessible to HRH residents to sufficiently measure exposure. Second, we launched an observational cohort following 106 HRH residents at 2 time periods over 12 months. Finally, we invited a subset of 28 cohort members to take part in repeated, longitudinal one-on-one interviews to gain greater insight into HRH, development of social cohesion and collective efficacy, and drug-related outcomes. Protocol adaptations due to housing shifts, over policing, and serendipity were applied.