Shot of Confidence: Building Trust in Vaccination Programs

A new paper in the Journal of Public Health finds that highlighting the harms of not getting vaccinated is a more effective message than emphasizing the benefits of vaccination for individual patients or the benefits to public health.

Vaccination remains the most economical and effective public health strategy for reducing morbidity and mortality. But some vaccines, such as those for flu, pneumonia and HPV, are given voluntarily. Often, due to misinformation or ignorance, many people are reluctant to get vaccinated for various diseases (or to vaccinate their children).

For years, researchers have been investigating various strategies to try to persuade people to get their vaccines. This study, in China, designed a scenario experiment consisting of three experimental groups and one control group to test the effectiveness of various messaging strategies to induce people to get vaccinated for COVID-19.

For the first group, researchers gave them information that described the personal benefits of vaccination: "Vaccination can make you develop antibodies against COVID-19, thus reducing the likelihood of contracting COVID- 19 and developing severe symptoms after infection."

The second group received messages highlighting the benefits of vaccination for other people: "Vaccination can promote the formation of community herd immunity, thereby reducing the likelihood of community members getting infected with COVID-19 and developing severe symptoms after infection."

Investigators provided the third group of participants with information about the potential harm of not getting vaccinated: "If you are not vaccinated, you will not develop antibodies to COVID-19, and thus you will be more susceptible to COVID-19 and more likely to develop severe symptoms after infection."

The study found that while all groups targeted for vaccination were more likely to get a vaccine than the control group, the "potential harm" message patients showed the highest probability of vaccination, 72.6%. The "personal benefits" message group was 65.5% likely to get vaccinated. The "benefits other people" message group was only 62% likely to get vaccinated. Emphasizing the personal risk of not getting vaccinated was more effective than highlighting the potential personal gains of vaccination or benefits to the community.

"Previous studies on the impact of message frames on vaccination have rarely considered the different stages of vaccine launch," said the paper's lead author, Ke Feng. "This study explored the effect of information frames on vaccination in the late stage of vaccine launch when the vaccine is perceived to be effective. The findings of the study can provide valuable insights for improving the ability of governments to respond to pandemics."