Effects of fact-checking warning labels and social endorsement cues on climate change fake news credibility and engagement on social media

Koch, Timo; Frischlich, Lena; Lermer, Eva

Abstract

Online fake news can have noxious consequences. Social media platforms areexperimenting with different interventions to curb fake news' spread, oftenemploying them simultaneously. However, research investigating the interaction ofthese interventions is limited. Here, we use the heuristic‐systematic model ofinformation processing (HSM) as a theoretical framework to jointly test twointerventions against fake news that are implemented at scale by social mediaplatforms: (1) adding warning labels from fact checkers to initiate systematicprocessing and (2) removing social endorsement cues (e.g., engagement counts) toreduce the influence of this heuristic cue. Moreover, we accounted for dispositionspreviously found to affect a person's response to fake news through motivatedreasoning or cognitive style. An online experiment in Germany (N= 571) confirmedthat warning labels reduced the perceived credibility of a fake news postexaggerating the consequences of climate change. Warning labels also loweredthe (self‐reported) likelihood to amplify fake news. Removing social endorsementcues did not have an effect. In line with research on motivated reasoning,left‐leaning individuals perceived the climate fake news to be more credible andreported a higher likelihood to amplify it. Supporting research on cognitive style,participants with lower educational levels and a less analytic thinking style alsoreported a higher likelihood of amplification. Elaboration likelihood was associatedonly with age, involvement, and political leaning, but not affected by warning labels.Our findings contribute to the mounting evidence for the effectiveness of warninglabels while questioning their relevance for systematic processing.