Police involvement in interagency crisis mental health first response pathways in England: A realist and cost consequence analysis. PIONEER-MH.

Research question: What is the impact of the Right Care Right Person (RCRP) policing strategy on the implementation, delivery, costs, and outcomes of multi-agency first response mental health crisis pathways in England? Background: Police encounters for people experiencing mental health crises are distressing. A detailed understanding of how these complex interfaces work, alongside their cost effectiveness is needed. Policy and legal changes involving the Mental Health Act and the RCRP policing initiative are now in place, but the impact on people in crisis, services (MH Trusts, Ambulance) or voluntary sector is unclear. It is also important to investigate any disproportionate impact on people from disadvantaged backgrounds, (e.g. socio-economic, cultural, or ethnicity). Aim/objectives: To understand and evaluate the implementation, delivery, costs and outcomes of community multi-agency first response mental health crisis pathways in England in response to the policing strategy 'Right Care Right Person' -Using realist methods, map the architecture of the first response mental health crisis pathways including identification of routine data -Develop, test, and consolidate Initial Programme Theories (IPTs) using mixed methods -Explore and analyse longitudinal data for identified outcomes to inform a cost consequence analysis and a budget impact tool Methods and delivery timeline: Realist study design, with embedded observational mixed methods, to evaluate community multi-agency first response mental health crisis pathways in four study sites in England. Study sites have been chosen for variations in population, indices of deprivation, use of police holding powers and different configurations of collaborative working between police and other services. Four peer researchers and 24 PPI members will provide lived experience oversight across study sites. There are three workstreams: 1) Identify Initial Programme Theories (IPTs)- months 1-14. Develop IPTs through documentary analysis, 15 individual stakeholder interviews in each site and a stakeholder workshop (n=60) across sites. Interviews will support context mapping of the multi-agency system of first response services in each site including the identification of available routine data. 2) Test the IPTs using mixed methods- months 8-32. Test the IPTs including quantitative analyses of routine data and interviews/focus groups with staff, service users and carers. Factors explaining the experiences of people from under-served/marginalised populations focusing on socio-economic, cultural, or ethnic heritage will be identified. Realist logic will be used to identify causal relationships between context, mechanism, and outcomes informed by both routine data and in-depth data from a maximum sample size of 80 staff, 60 service users and 20 carers through interviews/focus groups. A series of workshops (40 stakeholders) will focus on validation/consolidation of IPTs and context specific knowledge mobilisation. 3) Conduct a cost consequence analysis within and between study sites- months 11-32. Use routine data to conduct a cost consequence analysis in four study sites followed by a comparative analysis across sites. Impact and dissemination: Knowledge mobilisation is embedded across the study to optimise the impact and adoption of outputs all supported by PPI. Outputs include commissioning and policy guidance, budget impact tool, lay summaries, academic papers and conference presentations.