Evaluating the impact of the UK’s first saNctioned sAfer drug Consumption faciliTy (ENACT): Protocol for a mixed-methods natural experiment study

Background The Scottish Government committed funding to pilot the UK’s first sanctioned Safer Drug Consumption Facility (SDCF), providing a safe place for people to inject drugs, in Glasgow. This protocol describes our plans to conduct a mixed-methods natural experiment study to evaluate the impact of the SDCF on health, social, community, environmental, and economic outcomes. Methods A process evaluation will use qualitative interviews with service users/providers and other stakeholders to explore barriers and facilitators to delivery, and the role of context in shaping delivery and outcomes. Quantitative measures of engagement, referral pathways, and adverse events will be captured. To estimate the causal effect on people who inject drugs, changes in overdose-related ambulance callouts and other health and social outcomes pre and post introduction (and by intensity of intervention exposure) in Glasgow (compared to control areas) will be assessed using administrative health records, data-linkage and a bio-behavioural survey. Impacts on the wider community will be assessed using repeated community surveys to examine trends in community cohesion and perceptions/experiences of safety/crime compared to control areas. Systematic social observation will examine changes in drug-related litter over time. Repeated focus groups with the local community will explore how perceptions evolve as the intervention becomes embedded. For the economic evaluation, within-study cost-effectiveness and cost-utility analyses will quantify SDCF costs and health outcomes from a health and social care perspective. A broader cost-consequence analysis will adopt a societal perspective considering costs and benefits holistically (including criminal justice, housing market, and local economy). A dynamic mathematical model will evaluate longer term impact and cost-utility of the Glasgow SDCF and the potential impact of SDCF models in other UK settings. Anticipated impact Findings will inform decisions on the future of the SDCF in Glasgow, as well as potential introduction of similar facilities elsewhere in the UK and internationally.