An Empirical Study of Agenda-Setting Effects of Digital News Platforms on Issue Salience Among Nigerian Millennials

The agenda-setting function of traditional media has been well documented, but its operation in the digital news environment characterised by algorithm-curated content, user-driven feeds, and multi-platform information exposure requires fresh empirical examination, particularly for the Nigerian millennial demographic. This study empirically examined the agenda-setting effects of digital news platforms on issue salience perceptions among Nigerian millennials aged 25 to 40. A longitudinal panel survey was conducted with 220 participants in Abuja, Lagos, and Kano across three measurement waves separated by four-week intervals. Issue salience was assessed for ten policy issues at each wave. Digital news platform usage logs were captured through a consented app measuring tool. Intermedia agenda-setting was tested by correlating platform issue prominence (measured through API scraping of issue frequency on WhatsApp news groups, Twitter/X trending topics, and four major news app feeds) with individual issue salience at each lag. Results showed significant positive correlations between digital platform issue prominence and individual salience at a two-week lag for hard news topics (r = 0.48; p < 0.001) but weaker correlations for social and lifestyle issues. Algorithm-curated platforms showed stronger agenda-setting effects than open-timeline platforms. Cross-platform exposure reinforced agenda-setting effects. The study provides original panel-based evidence of digital agenda-setting in a Nigerian context, identifying implications for civic communication strategy and information ecosystem governance. Keywords: agenda-setting, digital news platforms, Nigerian millennials, issue salience, panel study