Agenda-setting effects across political and platformized contexts: a meta-analysis

Abstract

This article reports a quantitative meta-analysis of agenda-setting effects across political and platformized communication contexts. The analysis draws on a 30-study analytic sample selected from a local full-text corpus of 973 records, with 20 studies providing convertible effect sizes and variance estimates for the weighted synthesis. The central question is whether the correspondence between media salience and public, policy, or platform-mediated salience varies across geographic context, regime type, internet/media openness, and a post-2021 proxy for intensified platformization and AI-mediated communication. The primary effect-size metric is Fisher’s z -transformed correlation, with transformed r reported for interpretation and Cohen’s d used only as a secondary translation. Results indicate a strong positive overall agenda-setting effect and substantial heterogeneity, while moderator patterns are directional but statistically non-significant in the weighted analytic sample.