Individual differences and anti-vaccine radical collective action intention: The moderating role of group norms

This research comprises three studies conducted in the United States and Poland, investigating predictors of radical action intentions within anti-vaccine movements. The American sample included 252 participants (N1), while the Polish samples had 316 (N2) and 538 (N3) participants. The studies focused on the association between personality traits (meanness, disinhibition, subclinical sadism) and willingness to engage in radical collective action. Building on previous work connecting antisocial tendencies to social behaviours, our research delves into the specific link between non-clinical traits and violent collective actions. Across all studies, positive and significant associations were found between these traits and radical collective action intentions. Notably, our findings highlight that the perception of social norms moderates these relationships. When radical actions are perceived as normative, the link between disinhibition and willingness to choose radical means is stronger and significant. Conversely, when actions are seen as non-normative and unacceptable, the relationship weakens. This moderation effect is consistent in both Poland and the United States, with some observed differences in the strength of indirect effects. The synthesis of insights from personality and social psychology proves vital for a nuanced understanding of collective behaviour.