A comprehensive new review led by researchers from the NIHR Health Protection Research Unit (HPRU) in Evaluation and Behavioural Science at the University of Bristol, in collaboration with the HPRU in Vaccines and Immunisation at the London School of Hygiene and Tropical Medicine and the UK Health Security Agency, combined data from more than 200 trials comprising over 6 million participants. The findings indicate that vaccination programmes should prioritise ensuring vaccines are accessible, convenient, and affordable for the recipient.
Vaccination is one of the most powerful public health tools, yet uptake of many vaccines has declined in recent years, exacerbated by the COVID-19 pandemic. Tackling this decline is a key public health priority.
The authors analysed data from 223 trials of interventions aimed at supporting people to receive recommended vaccinations. This included studies carried out among people of all age groups (from infants to older adults) to increase uptake of any vaccine routinely offered in the UK.
Dr Clare French, Senior Research Fellow at the University of Bristol and Principal Investigator on the project said:
“Achieving high vaccination coverage is essential for protecting population health and preventing outbreaks of vaccine-preventable diseases. Policy makers need reliable, comprehensive evidence on which interventions work best to increase vaccine uptake. This allows resources to be directed toward strategies that deliver the greatest public health benefit”.
Interventions were grouped into six broad categories: those improving access, enhancing affordability, providing education, sending reminders, combining education and reminders, and multi-component interventions that mix two or more strategies.
All six intervention types increased vaccine uptake compared to usual care or doing nothing. Strategies that targeted affordability (such as reducing costs or offering incentives), improved access or convenience, or used multiple combined strategies were the most effective.
The review is the first to explore the impact of the COVID-19 pandemic on intervention effectiveness. Early evidence suggests that the effectiveness of some of these interventions may have been affected by the pandemic – this situation needs to be monitored.
Dr Sarah Davies, Senior Research Associate at the University of Bristol and lead author on the review said:
“Future studies should focus on further investigation and optimisation of access and affordability interventions. In addition, analyses by ethnicity and socio-economic factors should be incorporated – these are currently lacking – but would be important for informing decision making and helping to address inequities in vaccination.”
This research was funded by the National Institute for Health and Care Research (NIHR) Public Health Research Programme (Grant Reference Number NIHR135130) and supported by the NIHR Health Protection Research Unit in Evaluation and Behavioural Science at the University of Bristol.
