Framing Messages for Vaccination Supporters

"Subtle changes in the way information about vaccination is presented can affect how people perceive it."

Many efforts at convincing antivaccine individuals have failed or even backfired. These failures may reflect the lack of trust antivaccine individuals place in the medical establishment. In the area of public opinion more broadly, the role of peers to relay messages from the media or other official sources is well known. As a result, members of the public may be in a good position to convince vaccine-hesitant individuals, if only they could muster convincing arguments, be able to memorise them, and be willing to transmit them to others. As with any message, common provaccination messages have to be framed one way or the other. The researchers conducted 7 experiments on 2,761 provaccination online participants from the United States (US) and United Kingdom (UK) to test whether the valence of a statement (positive or negative) and its rhetorical orientation (pro- or antivaccine) affected whether messages for their peers are: (i) found plausible, (ii) remembered, and (iii) shared.

To test whether framing influences the steps necessary for a statement to be used by a provaccine individual in informal discussions, the study examined: (i) evaluation of message plausibility (Experiments 2 and 5), (ii) memorisation of the message (Experiment 3), and (iii) willingness to transmit the message further (Experiments 4 and 6) - as well as (iv) the propensity to use the statements to convince someone who refuses to vaccinate (Experiment 7). The statements had 2 contents, relating either to vaccine side effects or to the medical consensus on vaccination. Experiment 1 aimed at establishing that the researchers' predictions about the direction of rhetorical orientation of the experimental statements (in favour or against vaccination) were accurate. Thus, participants were presented with a statement like "999 people out of 1,000 don't have any severe side effects after being injected with a vaccine" and then asked whether the person who uttered this statement would be more likely to be in favour of vaccination or against it. Experiment 1 established that the statements' valence could be positive or negative and that the statements could be perceived as strongly provaccination or as being ambiguous between being pro- and antivaccination.

After conducting all 7 experiments, and contrary to previous research, the study found that negatively framed statements, compared to positively framed statements, were not better memorised (Experiment 3), were deemed less plausible (Experiments 2 and 5), and were less appealing to transmit (Experiments 4 and 6). Rhetorical orientation had no effect on memory, but participants deemed more plausible (Experiment 2), and were more willing to transmit (Experiment 4), statements whose rhetorical orientation better cohered with their own views, compared to statements that didn't. Overall, the framing effects observed were dramatic: one framing made participants very eager to transmit a statement, while another made them reluctant to transmit it at all.

These strong framing effects indicate that: (i) Positively valenced statements prompted participants to adopt a more positive attitude toward vaccination; (ii) in the case of statements about the scientific consensus, participants were more likely to use positively valenced statements to argue against someone who opposes vaccination; and (iii) framing effects were clearly perceptible in the way participants framed the arguments they chose to use, with nearly all arguments being framed with a provaccination rhetorical orientation.

As a practical example: Information campaigns often frame information about vaccines side effects negatively, albeit with a provaccination rhetorical orientation - e.g., "Severe side effects are extremely rare." A positive frame - e.g., "The overwhelming majority of people do not have any side effects" - might be more easily further transmitted by provaccination audiences.

The researchers stress that it is "important to test, on a case-by-case basis, the effects of positive or negative framing, and to acknowledge that framing could differently affect memorization, plausibility evaluations, willingness to share, and actual sharing behaviors." They thus "encourage future research to combine different measures and not to presume that framing will have the same effect on multiple measures."

In conclusion, messages aimed at reinforcing the argumentative tools of provaccination individuals should consider the way the messages are framed because "seemingly superficial features of vaccine communication might have a substantial impact on how some provaccine individuals process the communication, making it more or less likely that they transmit it further. In particular, some frames - in the case at hand, positive frames - appear to make provaccine participants more likely to accept and transmit provaccine messages, which are intrinsically desirable outcomes."