What Messaging Persuades People to Get the Eventual COVID-19 Vaccine?

"It is critical to start understanding baseline intent to vaccinate and how to persuasively communicate about the importance of vaccination now, given the deluge of misinformation about the virus and heightened distrust."

Research indicates that, even when a safe and effective vaccine against SARS-CoV-2 (COVID-19) is available, there may be challenges related to trust and uptake. Vaccine messaging, which might be used to encourage people to accept a vaccine, isn't always intuitive or one-size-fits-all. In that light, the data science firm Civis Analytics undertook a randomised controlled trial (RCT) to test 5 messaging themes, each of which described the importance of vaccination but emphasised a different reason why. The purpose was to understand which message would be more likely to convince adults in the United States (US) to get vaccinated.

Using a survey conducted on August 17, 2020, the RCT involved dividing 3,954 US respondents into 6 groups, 5 of which saw a message related to COVID-19 vaccination, as well as a control group that did not see any message. Messaging themes tested were:

• Safety, which aimed to alleviate concerns about the vaccine by highlighting the US Food and Drug Administration (FDA)'s extensive testing process and emphasising how a shortened timeline (as per "Operation Warp Speed") would only impact the cost of development, not safety and effectiveness.
• Economic recovery, which emphasised the economic devastation caused by COVID-19 and the vaccine's role in an accelerated path to recovery.
• Statistics, which featured data about COVID-19 as a leading cause of death in the US, as well as the prolonged symptoms impacting the quality of life of those who have technically "recovered".
• Personal story, which shared the tale of a young, otherwise healthy American who died from COVID-19.
• Community, which explained herd immunity and emphasised the vaccine's role in making communities healthier for everyone, including those who are unable to get vaccinated.

After data collection, Civis built and ran a statistical model that calculated the impact of each message on support for COVID-19 vaccination, controlling for respondent characteristics. Key findings:

• The "personal story" message was most effective, increasing overall likelihood to vaccinate by 5 percentage points. There was little to no probability for backlash (i.e., people indicating they would be less likely to get vaccinated after seeing a message).
• "Economic recovery," "safety", and "community" were least effective across all demographic and geographic categories. They all had a high probability of backlash and are therefore not recommended. In fact, the worst-performing message was "community". When people were shown an ad that emphasised this message, they were 1% less likely to get the vaccine, and there was a 69% probability such a message would create a negative backlash.
• The degree to which each message was effective or not varied slightly by some subgroups. For example, the "personal story" message was most effective for those in rural areas (+8 percentage points), those with less than a college education and those who make less than US$75K/year (+7 percentage points in both cases), and among white Americans and those aged 50-64 (+6 percentage points in both cases).
• "Statistics" was somewhat effective among some subgroups, but only in a statistically significant way among those aged 50-64 (+6 percentage points).
• Civis notes that baseline intent to vaccinate, regardless of message, also differed by subgroup. Intent to get vaccinated with a future COVID-19 vaccine is lower among people without a college degree and those with a lower income. Women were also less likely to report they would get vaccinated than men.

Civis previously conducted similar studies on flu and human papillomavirus (HPV) vaccine messaging (in 2018 and 2019, respectively). Key findings in those studies:

• As in the present investiation (about COVID-19), the HPV research found that a message about vaccine safety is ineffective, despite people reporting "safety" as their biggest vaccination-related concern.
• Although personal stories were effective for both flu and COVID-19 vaccine messaging, the "community" theme was most persuasive in the flu research, but ineffective for the COVID-19 vaccine. (This could be due to the fact that the COVID-19 vaccine has become highly politicised in the US, whereas the flu vaccine is more familiar and thus more conducive to altriustic motives.)

A key takeaway from the study is that pharma and public health agencies working to communicate about a future COVID-19 vaccine should not plan to simply repurpose vaccination messaging strategies that have been used for other viruses or diseases.

Civis plans to re-run this research to understand how current events and potential misinformation impact "persuadability" over time.