Online incivility: A systematic literature review of its definition, effects and theoretical frameworks

In this systematic review, we analyzed 67 peer-reviewed articles published between 2005 and 2025 that employ experimental designs to establish clear causality. Specifically, we focused on how online incivility is defined, operationalized, and theorized, as well as its documented effects. We found that there was a lack of theory unique to incivility; the main sites of online incivility are the comment sections of social media platforms and news websites; most of the reviewed studies explored online incivility’s impact on individuals’ affect, cognition, and behavior/behavioral intentions, and most of them were related to political issues. As such, our findings suggest the importance of integrating prior findings to build a comprehensive theory of online incivility, as one of several recommended directions for future research in this field. This review also underscores the need for researchers to widen the lens of their investigations beyond political contexts and explore the impact of online incivility with other topics on individuals and wider societal groups.