In the more than 35 years of international Drug Consumption Room (DCR) existence, much evidence has been accumulated about their effects. In particular, four domains were consistently explored: (I) public health indicators related to the population of People Who Use Drugs (PWUD) (e.g. mortality and morbidity), (II) the characteristics of the target group population of DCR users and their consumption behaviour and profiles, (III) environmental effects of DCRs on their neighbourhood, including public safety, public nuisances, and local criminality, and (IV) the capacity of DCR to contribute to recovery and rehabilitation of PWUD, including access to other social and care services (1-3). A considerable bunch of published studies indicated significant positive effects, whilst most commonly negative outcomes expected, such as increase of drug use, increase of acquisitive criminality, or an attraction of PWUD in the vicinity of DCRs, were not shown.

However, despite the quantity of evidence, several reviews indicated that the quality of evidence was moderate (3-5). Although it is understandable that an experimental design is hardly feasible in order to evaluate such type of setting, most evidence resulted from observational and cross-sectional studies. Only a few studies were prospective cohort studies, and only four facilities in three cities (in Sydney, Vancouver, and Barcelona) were evaluated against comparative cases. The existing quasi-experimental studies covered overdose incidents, accessibility to consumption material, and crime. A recent study in France also assessed risky consumption practices (6). There are, however, no quasi-experimental studies available regarding other health outcomes and treatment uptake. In addition, a considerable part of the evidence was produced using overlapping methods and data. It is a paradox that the oldest DCRs and the vast majority of them are established in Europe, but most studies examined the facilities that are established outside Europe. Finally, for what concerns more particularly the current and future establishment of high-quality DCRs in Belgium, there is no evidence taking into account the peculiar legal and policy adverse context in which these facilities are placed, and how this context may weigh on their functioning and sustainability.

Considering this context, the Reve-Droom project includes a main study component and several complementary work packages. The main study will be based on a natural experiment with a longitudinal, comparative study setting across three sites: the existing DCR in Liège (“Såf ti”, established in 2018), the DCR in Brussels (“Gate”, established in 2022), and a control site in a similar urban area in Flanders (where no DCR has been established so far). Individual health and social data on DCR users and controls will be collected continuously and assessed at two time points (t = after 6 first months of the study period and t+1 = 18 months after). The data collected by the staff will include at least socio-demographic information, consumption profile (substances, mode of administration, frequency), services used within the DCR (syringe exchange, social support, medical support...), health status (in particular HIV and hepatitis status), care needs, and quality of life. The comparative design will be performed across time points within each site and across sites, as these sites are at different points of development of their DCR facility.

Additionally, complementary WPs will include: (1) an examination of the legal framework and management of the existing DCRs: local agreements with law and enforcement actors and protocols/actions taken in order to protect legally the facilities and staff. (2) An environmental study of the sites’ neighbourhood with retrospective examination of data available from the police and neighbourhood social services (such as discarded material and complaints) and qualitative data with neighbours about public safety. (3) A cost-benefit analysis of the DCRs based on an examination of the costs and benefits associated with the use of a DCR against the cost and benefits associated to the use of other settings alone, in particular the existing low-threshold services such as the MSOC/MASS and other harm reduction services.

The study will provide a framework for routine monitoring of DCRs over time in accordance with EMCDDA standards.