Title: Interventions to increase vaccine uptake: Systematic review and component network meta-analysis to identify the most effective strategies
Funder: Department of Health and Social Care

Abstract: Vaccination is very good at reducing illness and death from infectious diseases. However, for vaccination programmes to work well it is important that most people get vaccinated. This protects their own health and limits the amount of disease in the population. When not enough people are vaccinated, diseases can spread quickly. _x000D_ _x000D_ What is the problem? _x000D_ It is hard to make sure that most people take up the offer of vaccination. For example, the number of children getting their vaccinations in England has gone down in recent years. This had led to more children catching diseases that could be serious. Meanwhile, the number of people getting vaccinated is lower in some communities. This can mean that some people’s health is more at risk than others. The UK Health Security Agency thinks that increasing vaccine uptake is high priority._x000D_ _x000D_ Many different methods are used to encourage more people to be vaccinated. These include education programmes, media campaigns, sending reminders and making it easier to get a vaccination e.g. at a ‘pop up’ clinic. There are important questions around which methods work best, for which groups of people and in which situations. _x000D_ _x000D_ What will we do? _x000D_ We will search for and look at studies that report on ways to increase uptake of vaccines. We will include studies on all population groups and all vaccines. We will use a special technique to look at how well the different methods work when compared with each other. We know that many of the ways used to encourage people to get vaccinated are made up of several parts. Our approach will also allow us to ‘unpack’ these parts and see which work best in different groups of people and situations. _x000D_ _x000D_ The number of people getting vaccinated is lower in some groups including some ethnic minority groups and low-income communities. Our research will help find the best ways to support these groups to get vaccinated. We will also study the costs of the methods that we find work best. Our work will help public health teams know how best to increase vaccination rates in their population and at what cost._x000D_ _x000D_ Who will work with us? _x000D_ We will work with members of the public, holding regular meetings to make sure their views help shape our research. We will work closely with interested parties (e.g. UK Health Security Agency) to make sure our research is useful for them. To make sure that our findings reach the right people we will work with our communications partners and members of the public._x000D_ _x000D_ Who will benefit?_x000D_ Our findings will be of wide benefit to the general population. We are all at risk from infectious diseases, as the COVID-19 pandemic has shown. Making sure there is high uptake of vaccinations is vital for controlling this major threat to human health, both now and in the future.

Lay abstract: Introduction_x000D_ Vaccines are an extremely powerful and cost-effective public health intervention to reduce morbidity and mortality. Optimising vaccine provision is the first strategic priority in the Public Health England (now UK Health Security Agency) Infectious Diseases Strategy 2020-25. There are ongoing challenges in achieving and maintaining high and equitable vaccine uptake. _x000D_ _x000D_ A wide range of interventions have been implemented to increase vaccine uptake. These are typically complex, with multiple components. Existing reviews on the topic conduct traditional pair-wise meta-analyses which are not well able to address the complexity of interventions and the influence of the contexts in which they are implemented. Therefore, there are important gaps in the evidence around determining which interventions or features of interventions are most effective, in which population groups and contexts._x000D_ _x000D_ Research question_x000D_ Which interventions, or components of interventions, are most effective in increasing vaccine uptake in high and upper-middle income countries? _x000D_ _x000D_ Objective 1: Collate and appraise the evidence _x000D_ We will conduct a comprehensive systematic review and appraisal of randomised controlled trials and observational studies on any type of intervention targeting those eligible for vaccination (or their carers) to increase vaccine uptake. We will include studies on all types of vaccines and on all population groups living in the community._x000D_ _x000D_ Objective 2: Synthesise the evidence _x000D_ We will conduct network meta-analyses to examine broad intervention strategies individually and in comparison with others. This analytical approach allows the simultaneous comparison of multiple interventions in a single model and incorporates both direct and indirect effect estimates. Analyses will be conducted within a Bayesian framework._x000D_ _x000D_ Objective 3: Explore variation in intervention effectiveness_x000D_ We will characterise intervention features using an existing taxonomy, adapting and supplementing this with a co-produced, de novo, high-level coding, working with stakeholders and our PPI group. We will develop additional (component) network meta-analysis models to explore intervention features and contexts in detail. This will allow us to identify the (most) effective components or combination of components and the contexts in which they are most effective. We will investigate inequalities in the effectiveness of interventions, considering key PROGRESS items. _x000D_ _x000D_ Objective 4: Assess the economic evidence _x000D_ We will collate intervention costs and any health economic evaluations of interventional approaches found to be effective (in Objectives 2 and 3). We will work with stakeholders to develop a hierarchy for the extraction of economic data items to ensure that outputs are useful for policy and practice._x000D_ _x000D_ Patient and public involvement_x000D_ We will engage a diverse PPI group including members of underserved communities, holding regular meetings to ensure that their thoughts and perspectives can inform all aspects of our work. _x000D_ _x000D_ Impact and dissemination_x000D_ Our findings will facilitate better informed and more tailored decision-making on strategies to increase vaccine uptake. We will work closely with stakeholders (e.g. UK Health Security Agency) and our PPI group to ensure the relevance and influence of our findings for practice and policy. Findings will be widely disseminated and mobilised via multiple channels.

Research activity codes: 3.4 VACCINES
Health categories: INFLAMMATORY AND IMMUNE SYSTEM