News & views: Vaccine Communication (Part 2): The Message and the Messenger

Editor’s note: This is the second of a two-part series related to vaccine communication. It is based on a presentation originally developed by Charlotte Moser for the Wilkes University Kimball Lectureship. Part 1 focused on the recipient of a vaccine-related message, and part 2 focuses on the message and the messenger.

Rhetoric is defined by the Cambridge Dictionary as “speech or writing intended to be effective and influence people.” Aristotle’s "Theory of Persuasion" speaks to the necessary components for delivering this influence:

1. Logos or lines of proof
2. Pathos or evocation of emotion
3. Ethos or credibility of source

The first two of these address aspects of communication addressed in part 1, further highlighting the importance of considering the recipient in any communication. In part 2, we will describe a communication theory that offers a framework for delivering a message while considering the individual nature of and complex milieu surrounding its recipient. Then, we will turn our attention to the third component of Aristotle’s theory, ethos, or the credibility of the messenger.

A framework for considering how messages can affect change

In part 1, we considered an array of factors that shape an individual’s receipt of a message. You might have even wondered how we can possibly deliver effective messages in light of those considerations. A theory of attitude change developed in the early to mid-1960s by Sherif and Hovland can help. Known as “Social Judgement Theory,” the authors described the cognitive structure of a person’s attitudes and how this structure affects message evaluation. Sherif and Hovland described three components of attitude structure:

1. Latitude of acceptance – the range of ideas and messages about a topic with which the individual agrees
2. Latitude of rejection – the range of ideas and messages about a topic with which the individual disagrees
3. Latitude of noncommitment – ideas and messages about the topic that do not have a positive or negative effect

For example, if someone is presented with a series of statements about vaccines and asked to sort them based on their agreement or disagreement, the sorted statements would provide a framework of the individual’s vaccine attitude structure. If the individual was then asked which idea most aligns with their views, that would be considered their “anchor statement.”

According to Sherif and Hovland, if a topic is extremely relevant to the individual, it is more difficult to change their attitudes. To account for this, the theory refers to one’s “ego involvement.” As vaccine communicators and administrators, most of us are likely to have a high ego involvement related to vaccines. So, too, would people who demonstrate against vaccines. Both groups would have less malleable attitudes than many others in the population.

So how does knowing a person’s attitude structure and ego involvement help with message delivery? According to Sherif and Hovland, when a person evaluates a message, they will judge it based on their existing attitudes and then adjust their thinking accordingly. For example, a message that falls within a person’s latitude of acceptance will be accepted and the person will adjust their thinking to accommodate the new information or message. However, if the message falls within their latitude of rejection, not only will it be unacceptable, but it may also make them “dig in” on their pre-existing ideas. Said another way, a disagreeable message could have a boomerang effect. According to the authors of the theory, the biggest opportunity to change attitude is to deliver a message that is as far from one’s anchor statement as possible, but which still falls within their latitude of acceptance because it will require the biggest adjustment to their thinking. Unfortunately, but important for communicators, this explains why a message does not typically cause a large-scale about-face. Rather, it suggests that a series of small changes will accumulate over time to generate overarching change. And while this is not what a communicator (or clinician) wants to hear, it provides an understanding that any positive change to one’s attitudes should be considered good progress.

Messengers, the ecosystem and trust

Another important component of communication is the messenger. We witnessed this during COVID-19 vaccine rollout, where in some places, community partners were more effective messengers than public health officials. So, what do we know about this?

As described, Aristotle’s theory of persuasion focuses on the credibility and perceived competence of the messenger. Today, we talk a lot about trust. Trust takes time to build, but sometimes we are asked — or are asking others — to trust in the absence of time. This is where credibility and perceived competence become important surrogates. In 2022, the Ad Council Research Institute conducted a study in which participants were asked what makes someone trustworthy. Among 2,500 participants, 65% to 70% indicated that people who demonstrate honesty, consistency of message, lack of bias, and an acknowledgement of both sides of an issue are considered more trustworthy. In contrast, people who are endorsed or paid by companies, influencers, government officials, and popular national or local voices do not enjoy the same level of trust. Importantly, both the Ad Council survey and longitudinal surveys by the Pew Research Center found that medical professionals and scientists are among the most trusted occupational groups; however, the fragility of this trust was also apparent. Among Ad Council survey respondents, the percent indicating trust varied based on political leanings and geography (urban, suburban, rural). Likewise, the Pew data varied across time. When asked about the likelihood of various types of professionals to act in the best interest of the public, the highest percentage of confidence among Pew respondents came during 2019 and 2020, but data captured at the end of 2021 suggested some erosion in that confidence (albeit confidence was still greater for these professionals than many others).

Another aspect of trust relates to how a message is being used. Trusted messengers vary depending on whether someone is becoming aware of a topic, learning more about it, or making a decision using the information. To describe this, the Ad Council created a model, called the “trusted messenger ecosystem,” in which a series of concentric circles represent each use with decision-making requiring the most trust and subject awareness requiring the least. As described by the authors, “Broader reach helps drive initial awareness, but for becoming more and remaining informed, Americans generally trust messengers with either a close personal connection or expert credentials” (p. 15). If you’ve watched “Meet the Fockers,” it’s those in the “circle of trust” that most influence decision making. However, all is not lost when influence is low. According to the Ad Council report, individuals outside of the most trusted circle can still exert influence in one of two ways. First, they can work to exact change by influencing others who have more personal influence. Community messengers during COVID-19 vaccine rollout are an example of this approach. Second, as relationships develop, some people may gain influence. For example, over time someone in an individual’s social media network may gain more influence, particularly if the online interactions reinforce or enhance a more personal relationship.

Summing up part 2

The complexity of communication around a topic like vaccines is the result of an array of factors. Messages and messengers will be received differently based on the who is assessing them. Likewise, these assessments are not static. A message may become more or less palatable over time as an individual’s topical framework changes, and the perceived value of particular messengers can also change based on the intended use for information as well as changes to existing relationships between the messenger and the recipient. However, understanding the personal nature of message evaluation and the trusted messenger ecosystem can help communicators develop appropriate messages, determine who is the best messenger for their delivery, and hopefully, remove some of the frustration that can result when opinions are not dramatically changed by a particular message.

Conclusion

Part 1 of this series demonstrated the complex considerations around message recipients and the importance of placing them at the center of any communication strategy. Part 2 described considerations related to the message and the messenger — again placing the recipient at the center. Hopefully, by considering both discussions, you will be positioned to deliver the right message at the right time by the right person, and if a message is not received as intended, maybe you will at least be less frustrated and have a way to start sorting out the “why.”

References (Part 2)

Feldmann D, Foleno T, Thompson-Kuhn C, et al. The 2022 Trusted Messenger Study. 2022. Accessed May 16, 2024.

Griffin E, Ledbetter A, Sparks G. (2015). Social Judgement Theory in A First Look at Communication Theory, Ninth Edition, McGraw Hill Education.

Kennedy B, Tyson A, Funk C. (2022, Feb. 15). Americans’ Trust in Scientists, Other Groups Declines. Pew Research Center. Accessed May 16, 2024.

Sherif M, Hovland CI. (1961). Social judgement: Assimilation and contrast effects in communication and attitude change. Yale University Press.