Title: ‘Comprehensive’ interventions to prevent and/or reduce gang-related violence and other harms to health: a systematic review
Funder: Department of Health and Social Care

Abstract: Gang violence has a devastating impact on individuals, families and communities, leading to young lives ending tragically too soon. This has significant costs to the NHS and to society in general. Aside from criminality, it is associated with drug use, school dropout, unstable employment, mental health problems and areas of high deprivation, all of which are both causes and consequences of gang violence. For these reasons, it is increasingly recognised, both by expert researchers and in Government policy, that the most likely way of preventing or reducing gang violence and its impact is through closer working between people and organisations that can solve some of the issues related to gang violence. This includes Police, Health professionals, schools, local communities and organisations managing housing and the local environment. This approach has been called the ‘Comprehensive Gang Model’. Different versions of this approach have been tried worldwide, with differing amounts of success. ‘Comprehensive’ interventions typically involve several agencies working together and use more than one way of trying to reduce violence, e.g. combining orders to stop gang members gathering in a particular area with providing opportunities for education or work. Currently we do not understand the best way of using the ‘Comprehensive Gang Model’, what works best in different environments and why it works in some places and not in others. Our project will give us a better understanding of the ‘Comprehensive Gang Model’ so we can use it more effectively in the future._x000D_ _x000D_ We will review all the previous research on ‘comprehensive’ methods to tackle gang violence from the world’s scientific literature that provide a quality of data we can rely on (systematic review). We will find out what types of these interventions exist, and measure their impact on violence and other harms to health by combining data across studies if they are similar enough for us to do this (meta-analysis). We will take into account how well conducted the studies were that provide this data. We will look into what successful interventions have in common (their mechanisms), even when using quite different approaches, assessing how success varies by settings and situations (context), and what success actually means (different outcomes)._x000D_ _x000D_ Our team has previously carried out a similar review but this work, though still quoted today, searched for research in 2006 and now urgently needs updating, to add evidence from the UK we know exists for example. We will also find out the value for money of different models, as they vary widely in cost, and we need to know the balance between costs and benefits._x000D_ _x000D_ Our work came originally from a group of people from different organisations who wanted to find out ways to reduce gang violence in Birmingham, UK. Our current research team includes experts in public health, criminology, systematic review methods, and health economics. To make sure the new review is relevant to policy and practice, we will be using a review advisory group. The group will be made up of practitioners and policy makers (from both the crime and public health fields) and representatives of local communities where gangs are active. They will feed into the scope and direction of the review, and provide suggestions for how to implement the findings into practice. Working with them, we will then be able to share the research results to ensure they have the most impact possible.

Lay abstract: Background_x000D_ Gang membership is associated with violent offending, poor mental health, education and employment outcomes, and gang violence is a significant burden on the NHS and society. The most promising strategies to prevent and reduce gang-related violence are ‘comprehensive’ interventions, multi-pronged, typically multi-agency, approaches that incorporate prevention, intervention, and suppression activities. Such an approach is currently being promoted and funded by the UK Government, despite currently limited evidence to substantiate this. A rapid review published this year by Public Health England recommended more systematic searching and reviewing of the literature. Evidence is also needed on which characteristics of these complex interventions are effective, what mechanisms they operate through, and in what contexts, and on their cost-effectiveness._x000D_ _x000D_ Research questions_x000D_ RQ1. What is the nature and extent of interventions for gang-related violence?_x000D_ RQ2. What is the range of comprehensive interventions for gang-related violence and what are the critical mechanisms, contexts and outcomes through which they operate?_x000D_ RQ3. Which comprehensive interventions are most effective at preventing and/or reducing gang-related violence compared with usual service provision?_x000D_ RQ4. Which critical mechanisms are most important to the success of effective comprehensive interventions for gang violence, for which populations and outcomes, and in what contexts?_x000D_ RQ5. What is the cost-effectiveness of different types of comprehensive interventions for gang-related violence?_x000D_ RQ6. How do the findings map onto existing UK service provision for gang-related violence?_x000D_ _x000D_ Methods_x000D_ We will undertake a multi-component systematic review. Included studies must address our research questions and have a robust comparison group design with both pre-test and post-test measurements. The literature search will include Boolean database searching, browsing online resources, related-item searching and other methods. Two reviewers will conduct screening, data extraction and assess study quality of included studies using verified tools. We will narratively synthesise evidence of effectiveness and conduct meta-analyses where appropriate._x000D_ _x000D_ Research objectives/ delivery timelines_x000D_ To complete searching by December 2020_x000D_ To complete screening by February 2021_x000D_ To complete a systematic map of interventions by March 2021_x000D_ To extract data from and assess quality of included studies by November 2021_x000D_ To develop a typology of comprehensive interventions and synthesise theories of change by February 2022_x000D_ To consult with policy/ practice and community stakeholders on the synthesis by March 2022_x000D_ To synthesise outcome evaluation and cost effectiveness data by May 2022_x000D_ To consult with stakeholders on results and draft report, and finalise dissemination and implementation strategies by June 2022_x000D_ To submit the final report to NIHR by August 2022_x000D_ _x000D_ Anticipated impact and dissemination_x000D_ Our review advisory group includes practitioners, policy-makers and local communities. As the proposed research has been recommended by these organisations and relates to recent emerging practice recommended by UK Government, it is likely to find a receptive audience eager to implement its findings. We have allocated resources for dissemination events and are collaborating with stakeholders through the research process and in determining effective approaches to implementation to maximise impact.

Research activity codes: 3.1 PRIMARY PREVENTION INTERVENTIONS TO MODIFY BEHAVIOURS OR PROMOTE WELL-BEING
Health categories: GENERIC HEALTH RELEVANCE