The Behavioral Impact of Moral Appeals: An Integrated Framework and Meta-Analysis

Moral appeals-persuasive messages aimed at invoking moral obligations-are widely used across various contexts. However, evidence about their effectiveness in changing behaviors remains mixed, and little is known about the conditions that influence it. To address this, we conducted a meta-analysis with 67 papers (k = 399) to assess the overall impact of moral appeals on behavioral intentions and behaviors, and to test various moderators of this effect. Drawing on various theories, we proposed that both morality enhancers and hindrances can influence their effectiveness and investigated three groups of moderators (Moral Content, Social Aspects, Autonomy Restraints). Results showed that, overall, moral appeals had a small, positive effect (d = 0.22). Furthermore, Moral Content (negative framing) and Social Aspects (the presence of social norms) enhanced appeal effectiveness, while Autonomy Restraints (the use of assertive language) undermined it. Our findings provide important theoretical and practical insights into moral appeals.