Changing the minds of vaccine-hesitant adults

This study shows that public health messaging - and subtle information nudges - can shape our decisions.
- Dr Matteo M Galizzi
CDC on Unsplash

A study co-authored by LSE has found that vaccine-hesitant adults in the UK are far more likely to have their COVID-19 jabs if they are told that they can then travel abroad more freely.

The research, published in Science Advances, reveals which messages have been the most - and least - effective at changing the minds of those who are reluctant to have their COVID-19 vaccinations.

It has significant lessons for current and future public health campaigns that aim to ensure high take-up of COVID-19 booster jabs.

The researchers, including Dr Barbara Fasolo and Dr Matteo M Galizzi, Associate Professors of Behavioural Science leading the LSE Behavioural Lab for Teaching and Research (BL), studied more than 10,000 unvaccinated adults in the UK, France, Germany, Italy, Poland, Spain, Sweden and Bulgaria, in the spring and summer of 2021.

Participants were shown information about the COVID-19 vaccines available to them, whilst being shown one of three public health campaign messages aimed at increasing vaccination take-up rates. The first message emphasised how vaccines reduced the risk of becoming seriously ill or dying from COVID-19, the second stressed the benefits of having a vaccine passport to travel abroad, and the third highlighted how those who were vaccinated against COVID-19 were free to go to restaurants, cinemas and gyms without restrictions.

The participants were then asked if they were willing to be vaccinated to see which message had been the most - and least - effective.

There was huge variation in the take-up of COVID-19 vaccines across the eight countries at the time the study was carried out, with vaccine-hesitancy as high as 61.8 per cent in Bulgaria and as low as 6.4 per cent in Spain. In the UK, it was about 10 per cent among women and slightly lower for men.

The researchers, who are from the Technical University of Munich and the University of Trento, as well as LSE, found that all three messages from public health campaigns were effective among unvaccinated German adults.

In the UK, the message about travelling abroad managed to convince many unvaccinated adults to get their COVID-19 jabs, with those willing to be vaccinated rising from 22 per cent to 28 per cent.

In all other countries in the study, the messages did not increase uptake. In Spain and Italy, unvaccinated adults were even less likely to get vaccinated after reading the public health campaign message which emphasised the reduced risk of mortality or serious illness after the COVID-19 jab.

The researchers found that the lower the level of basic knowledge about health and the higher the prevalence of conspiracy theories in a country, the less likely unvaccinated adults were to change their minds. Those over 65 were also less likely to be persuaded by public health messages than other age groups.

The most common reason for the reluctance of those participating in the study to get vaccinated was a fear of side effects from the COVID-19 jabs. Some believed there was a lack of evidence that the vaccines worked and that they had been developed “too quickly”, and others distrusted their government and the pharmaceutical industry.

The UK adults were much more accepting of the AstraZeneca vaccine than those in other countries. While a third of the adults in the UK sample trusted the vaccine, less than 5 per cent of those in the German or Italian samples did.

Dr Matteo M Galizzi said: “Vaccines offer the most cost-effective way to combat COVID-19. We urgently need more effective public health campaigns to ensure high take-up of COVID-19 booster vaccinations.”

“This study shows that public health messaging - and subtle information nudges - can shape our decisions. We now know the major reasons why some adults are hesitant to get the vaccine. Public health messages need to respond to these concerns, and focus on communicating the rigorous and extensive testing of vaccines and the extent to which risks of side effects from jabs compare to risks from COVID and long COVID.”

The researchers also urged against a “one-size-fits-all” approach to vaccine campaigns.  The European Commission has advocated for a coordinated vaccination strategy. “This study shows that public health campaigns must be tailored to each country in which they are going to be rolled out as different messages are effective - or ineffective - in different countries”, Dr Galizzi said.

Speaking about the study, Dr Barbara Fasolo said, “This study also reveals a troubling regularity: the most hesitant and less willing to accept a novel vaccine are also the most vulnerable and in greatest need of protection and reassurance. They are those that have the deepest fears, lowest education, and lowest trust. To prepare for future waves of COVID-19 around the world, and future pandemics, it is important that public health campaigns and release of medical evidence are tested with the most vulnerable populations. Looking ahead, our team at the Behavioural Lab is now devoting its efforts to understanding how people ‘process’ public health messages. Once we know what people look at, or fail to look at, and why, we can then leverage on existing behavioural and decision science findings and design solutions that can help people process information better. Our future studies in the Behavioural Lab will be a step in this direction.”

Behind the article

Paper: Steinert, Janina I., Sternberg, Henrike, Prince, Hannah, Fasolo, Barbara, Galizzi, Matteo M., Büthe, Tim and Veltri, Giuseppe A. (2022) COVID-19 vaccine hesitancy in eight European countries: prevalence, determinants and heterogeneity. Science Advances.

The study is part of the European-funded PERISCOPE (Pan-European Response to the Impacts of COVID-19 and Future Pandemics and Epidemics), a network of thirty-two top European institutions. Under the steering of Dr Barbara Fasolo and Dr Matteo Galizzi, the LSE Behavioural Lab for Teaching and Research (BL) - a joint initiative from the Department of Management (DoM) and the Department of Psychological and Behavioural Science (PBS) – participated in the consortium and was awarded a grant by the European Commission in 2020 to gather evidence on the direct and indirect behavioural effects of a range of COVID-19 policy measures.