Media Modalities and the Spread of Fake News: Diagnosticity and Involvement Effects

The proliferation of fake news about climate change presents a significant challenge to global efforts to addressthis urgent environmental issue. While fake news was previously predominantly text-based, it has evolved in recent years toincorporate more dynamic multimedia formats like pictures, audio, and video, with the potential to significantly influenceusers and amplify its spread online. This study investigates how different presentation modalities (text-only, image with text,and video with text) influence the believability and dissemination of fake news about climate change. An online experimentwas conducted with 456 participants randomly assigned to view fake news posts in one of the three formats. The studyexamined the effects of these presentation formats on perceived accuracy and sharing intentions, as well as the mediatingrole of content diagnosticity and the moderating role of personal involvement. The experimental outcomes reveal thefollowing: 1) Video with text significantly enhances perceived accuracy compared to text-only format, while image with textshows no significant difference; (2) The effect of presentation format on perceived accuracy is mediated by perceiveddiagnosticity; (3) Personal involvement moderates these relationships, with highly involved individuals being less influencedby presentation format; (4) Perceived accuracy positively correlates with sharing intentions across all formats. The studycontributes to our understanding of fake news dissemination by integrating the MAIN model, cognitive theory of multimedialearning, and elaboration likelihood model. It highlights the role of the "realism heuristic" in processing fake news contentand reveals how perceived diagnosticity influences accuracy judgments. These findings provide valuable insights forresearchers, practitioners, and policymakers working to develop effective strategies for combating fake news and promotingmedia literacy in the context of climate change communication. They suggest that media literacy programs should focus onenhancing critical evaluation skills, particularly for video content. Additionally, increasing personal involvement in climate change issues may lead to a more critical evaluation of information across different modalities.