Title: Title: Understanding the contextual factors that impact on the effective provision of opiate substitution therapy (OST) and needle and syringe programmes (NSP) in the UK: a multi-method study and realist evaluation of what works, for whom and under what circumstances
Funder: Chief Scientist Office, Scotland

Abstract: Plain English Summary_x000D_ Many people who inject drugs (PWID) experience serious harms including blood borne viruses (hepatitis C and HIV) and deaths from drug overdose. Over half of PWID in the UK have hepatitis C and the number of drug-related deaths is at its highest ever. Some groups of PWID (such as people who are older, younger, new to injecting, homeless, stimulant users and those out of treatment) are at more risk of harm and are the focus of this study. Two main harm reduction services in the UK are needle exchanges and opioid substitution treatment (OST) (usually methadone). Although we know that both services can reduce harms, there are concerns over whether they are being delivered, and used, in ways that make them most effective and best value for money. If we knew more about what makes these services more effective, then this could prevent more harms and deaths of PWID and provide better value services. This study aims to provide this understanding._x000D_ _x000D_ The 24 month study has 3 stages:_x000D_ _x000D_ 1.First, we will review published literature to find out what previous research can tell us about what helps or hinders effective delivery and use of these services. _x000D_ 2.Next, we will do an online survey of UK drug service commissioners to find out how OST and needle exchanges are provided, to whom, and using which models of delivery. This will help us identify what services are provided across the UK, using which models and what gaps in services exist. _x000D_ 3.Third, we will do a ‘realist evaluation’ where we will try to understand what service provision models, such as mobile needle and syringe programmes as compared to fixed sites, work best, for which high risk groups of PWID and why. We will choose 4 areas of the UK (one in Scotland and three in England) to collect information from a number of different sources to create and test a theory of what might work best for which groups of PWID and why. _x000D_ _x000D_ In step 1, a theory will be created from information collected in a literature review, from reviewing guidelines for OST/NSP service provision and from speaking to 8 senior service managers about how services are meant to work. In step 2, we will do up to 56 interviews with OST/NSP service commissioners, managers and staff of NHS and voluntary sector organisations, and managers from services that refer in and out of OST/NSP. We will interview up to 52 PWID in and out of contact with treatment services. We will ask people we interview about what helps and hinders the delivery or use of services in terms of access, engagement and retention. As an additional part of this stage of the study we will ask people about the cost of services including their use by PWID and examine some routine service data allowing us to find out the best value way to improve the impact of these services for PWID. _x000D_ _x000D_ We will write a report for funders, produce information for PWID and write academic papers and policy briefings for local/national policy makers about the research findings. We will hold events across the UK where we will share our findings to improve current services. _x000D_ _x000D_ We will involve PWID in all aspects of the study and have already consulted PWID on the relevance of our proposed research and some of the barriers that are met when using OST/NSP services. We will disseminate study results widely and will hold 6 events where we will invite service commissioners, providers, PWID and policy makers to attend. PWID will co-present and co-lead at these.

Lay abstract: Amongst people who inject drugs (PWID) in the UK, drug related deaths (DRD) are increasing and at their highest ever. (1,2). Hepatitis C (HCV) prevalence is high and there are current outbreaks of blood borne viruses (BBVs) including HIV (3,4). Sharing of injecting equipment is the key cause of BBVs in PWID and remains high (5,6.) Opioid substitution therapy (OST) is a key to preventing DRD but it is unclear whether treatment duration and retention are sufficient to reduce risk. OST and needle and syringe programmes (NSP) are effective (7-11), cost-effective (12,13) and routinely available. However, given the poor outcomes described above, there are clearly difficulties with optimal use, engagement and retention. To reduce harm, it is crucial to understand the barriers and facilitators to uptake/retention in different models of OST/NSP provision and in associated costs, particularly with groups at most risk of harms or poor outcomes: older/younger PWID, women, homeless people, stimulant as well as opioid injectors and those out of contact with services._x000D_ _x000D_ Study Aim: to understand the factors that impact on the use and effectiveness of (engagement, retention and harm reduction) high risk PWID in different service provision models as well as the cost of provision of these models. Our study will be conducted in 2 linked phases:_x000D_ _x000D_ Phase 1a) A qualitative meta-synthesis using systematic review methods to identify the contextual factors, barriers and facilitators that impact on the use and effectiveness (engagement, retention and harm reduction) of models of OST/NSP services. _x000D_ _x000D_ Phase 1b) A UK wide online survey of OST and NSP commissioners (n=183) to identify the range of services for PWID, including fixed and mobile NSP, the mix of prescribing services, including staff mix, service usage by various sub-populations of PWID, access and referral routes, and areas of provision. This will enable a better understanding of existing models of service provision and will provide essential context for Phase 2. _x000D_ _x000D_ Phase 2) A realist evaluation to examine in depth the contextual factors and mechanisms of action that impact on engagement and retention in OSTNSP services. Four UK case study sites will be selected to represent diverse models of OST/NSP provision. The realist evaluation will be conducted in three stages, in accordance with realist methodology:_x000D_ _x000D_ Stage 1 – Initial Programme Theory (IPT) will be developed utilising three data sources: the results of the systematic review; interview data from senior service managers; and analysing data from OST/NSP service guidelines/policy._x000D_ _x000D_ Stage 2 – IPT will be tested by collecting and analysing qualitative data via interviews (n=84) with 6 key stakeholder groups: OST/NSP service commissioners, service managers, and staff, staff of referring services, and PWID both in and out of contact with OST/NSP services. _x000D_ _x000D_ Stage 3 – Via analysis and interpretation of data collected at Stage 2 the IPT will be refined. Secondly, estimated costs of ‘optimal’ provision will be compared to existing services _x000D_ _x000D_ Project Timeline: Phase 1a completed by month 6, Phase 1b completed by month 4, Phase 2 months 7-21. Final report submitted by month 24._x000D_ _x000D_ Findings will be disseminated widely nationally and internationally, including by PPI. We will hold dissemination events, publish in academic journals and feedback through our established policy and influence routes to Governments, commissioners, practitioners and PWID.

Research activity codes: 8.1 ORGANISATION AND DELIVERY OF SERVICES
Health categories: INFECTION