Providing strong evidence for environmental claims in advertising: The moderating role of language complexity
(A2026-132627)

AUTHORS

CECILIE STAUDE, BI Norwegian Business School/Kristiania; Fred Selnes, BI Norwegian Business School

ABSTRACT

This study examines how the strength of evidence in environmental advertising influences consumers’ motivation to seek information and how this effect depends on language complexity. Drawing on persuasion knowledge, language expectancy, and fluency theory, we argue that strong evidence heightens curiosity and search intention only when presented in linguistically complex language that matches audience expectations for evidence-based communication. A 2 × 2 experiment manipulated evidence strength and language complexity in sustainability ads for a dairy brand. Results show that evidence increases curiosity and search intention only under high language complexity, and that complexity reduces skepticism by signaling credibility. The moderated mediation model confirms that curiosity mediates the effect of evidence on search intention when language complexity is high. Findings highlight the persuasive value of linguistic sophistication in evidence-based environmental advertising.