Evaluating the Impact of Using Mobile Vaccination Units to Increase COVID-19 Vaccination Uptake: A Synthetic Control Analysis for Cheshire and Merseyside, UK

Authors:

Xingna Zhang, John Tulloch, Shane Knott, Rachel Allison, Paula Parvulescu, Iain Buchan, Marta García-Fiñana, Roberta Piroddi, Mark Green, Ben Barr

Abstract:

Objective: To assess the impact on COVID-19 vaccine uptake of mobile vaccination units; vaccine provision that is temporally introduced into a neighbourhood using a large vehicle such as a bus or ‘pop-up clinic’. We further investigate whether such an effect differed by level of deprivation, ethnicity and age.

Design: Synthetic control analysis.

Setting: The population registered with General Practices in nine local authority areas in Cheshire and Merseyside in the Northwest of England.

Intervention: Mobile vaccination units that visited 37 sites on 54 occasions between 12th April and 28th June in 2021. We defined populations as having received the intervention if they lived within 1km of a mobile vaccination site. A weighted combination of neighbourhoods that had not received the intervention was used to construct a synthetic control group.

Outcome: The weekly number of first-dose vaccines received among people aged 18 and over as a proportion of the population.

Results: The introduction of a mobile vaccination unit into a neighbourhood increased the number of first vaccinations conducted in the neighbourhood by 25% (95% CI: 21% to 28%) within the three weeks after the first visit to a neighbourhood, compared to the synthetic control group. This effect was smaller amongst 30–65-year-olds compared to 18-30-year-olds, amongst Asian and Black ethnic groups compared to White ethnic groups, and the most socioeconomically deprived populations compared to the least deprived areas.

Conclusions: Mobile vaccination units are effective interventions to increase vaccination uptake, at least in the short-term. While mobile units can be geographically targeted to reduce inequalities, we found evidence that they may increase inequalities in vaccine uptake within targeted areas, as the intervention was less effective amongst groups that tended to have lower vaccination uptake. Mobile vaccination units should be used in combination with activities to maximise outreach with Black and Asian communities and socioeconomically disadvantaged groups.

Journal:

Social Science Research Network