Framing Messages for Vaccination Supporters

Efficiently communicating information on vaccination is crucial to maintaining a high level of immunization coverage, but it implies finding the right content for the right audience. Provaccination individuals, who represent the majority of the population, and who have been neglected in the literature, could play an important role relaying provaccination messages through informal discussions, if only these messages are (a) found plausible, (b) remembered, and (c) shared. We conducted 7 experiments on 2,761 provaccination online participants (United States and United Kingdom), testing whether the valence of a statement (positive or negative) and its rhetorical orientation (pro- or antivaccine) affected these 3 steps. Participants deemed more plausible, were more willing to transmit (and actually transmitted more), but did not remember positively framed statements better. Provaccination rhetorical orientation had little or no effect. 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. The framing effects also influenced vaccination attitudes, with participants exposed to positively framed statements reporting more positive attitudes toward vaccination. Since messages have to be framed one way or the other, the framing effects demonstrated here should be considered when designing public health messages. Public Significance Statement Subtle changes in the way information about vaccination is presented can affect how people perceive it. Participants found more plausible, and were much more likely to share, positively framed statements about vaccination than negatively framed statements. These framing effects should be taken into account when designing public health messages.