Processing Vaccine Misinformation: Recall and Effects of Source Type on Claim Accuracy via Perceived Motivations and Credibility

This study leverages the persuasion knowledge model (PKM) as a theoretical framework to examine how individuals process attempts at correcting measles, mumps, and rubella vaccine-related misinformation on Facebook. An experiment among U.S. adults ( N = 760) manipulates concurrent misinformation and correction sources to assess effects on perceptions of motives, credibility, and accuracy. The results demonstrate how "source blindness" compromises the attempts to respond to misinformation. Perceived accuracy of misinformation was serially mediated by perceived source motives and credibility but only among those correctly remembering the source. The study concludes with a discussion of how the PKM could be reimagined as a model better suited for misinformation research.