Words matter for any organization trying to reach an audience. The same goes for vaccine ads, according to a new WSU study. A recent WSU alumna and an associate professor conducted the first experimental study on how social normative messages in vaccine ads affect consumer behavior. 

Xizhu Xiao, strategic communications alumna, said the study found young adult participants were more interested in learning about the HPV vaccine when exposed to normative, injunctive messages. These messages implied friends and family encouraged getting the HPV vaccine.

The study also found negatively-worded messages increased people’s perceived risk of vaccines and lessened the interest in getting the vaccine, she said. These negatively-worded messages are commonly found on ads and campaigns for the World Health Organization and United Nations International Children’s Emergency Fund.

The experiment was designed by Xiao with some guidance from Porismita Borah, associate professor of strategic communications in WSU’s Edward R. Murrow College of Communication. 

While previous studies focused on descriptive norms versus injunctive norms, Xiao said her experiment focused on positive versus negative descriptive norms. Descriptive norm ads focus on how many people get a vaccine and use statements like “four out of five people get the HPV vaccine every year.” 

She said she also focused on injunctive norms versus a basic information condition. Injunctive norms focus on whether a person should get a vaccine by using statements like “professionals believe people should get the HPV vaccine if they want to mitigate risks of contraction.” Basic information ads provide consumers with the minimum amount of information about vaccines by using alternatives like “go to a local hospital to get more information about the HPV vaccine.”

Xiao said the experiment was originally a part of her graduation dissertation, with Borah acting as her advisor. 

She said Borah was invited to join the study and help with the conceptualization when it was submitted for publication in a journal called Health Communication.

Borah said the experiment was done online through Qualtrics. Participants for the study consisted of WSU students aged 18-29. They were then divided into four separate groups. Each group saw a different set of messages about the HPV vaccine. After viewing each message, they were asked about their feelings toward the vaccine.

Xiao said she was inspired to design the experiment after observing a vaccine ad from the WHO’s Instagram saying “One in 10 children miss out on life-saving vaccines.”

She said health organizations should use positively worded, injunctive and normative messages in future practices, especially for a possible COVID-19 vaccine campaign. 

Borah said organizations who use the positive, nominal and injunctive messages, as found in the study, could help increase vaccine intakes.

“We are seeing this particular study does have an effect on people who might change their mind,” she said. “Our study doesn’t directly look at whether these people are anti-vaccination or not, so that might be another future thing to look at.”

Xiao said plans for more studies in the future are being discussed and brainstormed. Xiao and Borah both expressed a desire to continue this study for other vaccines and demographics.