Persuasive Messaging to Increase COVID-19 Vaccine Uptake Intentions

"Given the considerable amount of skepticism about the safety and efficacy of a COVID-19 vaccine, it has become increasingly important to understand how public health communication can play a role in increasing COVID-19 vaccine uptake."

COVID-19 vaccine hesitancy has the potential to limit the efficacy of vaccination as a tool for ending the pandemic. Vaccination is both a self-interested and a prosocial action, so some researchers have investigated whether appeals that describe getting a COVID-19 vaccine as a way to protect others will increase willingness to vaccinate. The evidence of yet is unclear. The present study uses two survey experiments to study how different persuasive messages affect intentions to receive a COVID-19 vaccine, willingness to persuade friends and relatives to receive one, and negative judgments of people who choose not to vaccinate.

In the first experiment, fielded in early July 2020 with 4,361 participants, the researchers tested the efficacy of eleven messages against an untreated control condition (see Table 1 in the paper for full text of messages). A subgroup of the messages in Experiment 1 drew on a collective action framework of vaccination and emphasised who benefits from vaccination or how choosing not to vaccinate hurts one's social image. For example, the Not Bravery message reframed the idea that being unafraid of the virus is not a brave action but instead selfish, and that the way to demonstrate bravery is by getting vaccinated because it shows strength and concern for others. A second subgroup drew on contemporary arguments about restrictions on liberty and economic activity during the COVID-19 pandemic. For example, the Community Economic Benefit message argues that a vaccine will help return people's financial security and strengthen the economy.

Consistent with previous work finding prosocial appeals to be effective in promoting vaccination, the messages in Experiment 1 that increased COVID-19 vaccine uptake intentions were those that construed vaccination as a collective action problem. The messages that invoked concerns about one's social image if one chooses not to vaccinate also increased uptake intentions. All the collective-action-oriented messages increased intentions to advise a friend to vaccinate and negative judgments of those who do not, potentially creating spillover effects that induce others to vaccinate. In addition to this subgroup of messages, reframing vaccination as a way to restore freedom was also effective.

Experiment 2 tested the subset of the best-performing messages from Experiment 1 on a nationally representative sample of 5,014 adults in the United States (US) in September 2020. Notably, in the several-month period between Experiment 1 and Experiment 2, the US public had grown increasingly skeptical of a potential COVID-19 vaccine. In short, the prosocial messaging was found to be robust across subgroups, including those who are most hesitant about vaccines generally. Those high in vaccine confidence responded to all messages, while those low in confidence responded reliably only to the Community Interest messages.

In short, the study found that "Not only does emphasizing that vaccination is a prosocial action increase uptake, but it also increases people's willingness to pressure others to do so, both by direct persuasion and negative judgment of non-vaccinators. The latter social pressure effects may be enhanced by highlighting how embarrassing it would be to infect someone else after failing to vaccinate....This work could also help explain why social norm effects appear to overwhelm the incentive to free ride when vaccination rates are higher....That is, messages that increased intentions to vaccinate also increased the moralization of non-vaccinators suggesting that they are fundamentally linked to one another. These messages will need to be adapted in specific cultural contexts with relevant partners, such as community leaders."

In conclusion, the experiments "provide robust evidence that appealing to protecting others has effects on intentions to get vaccinated and to apply social pressure to others to do so as well."