Environmental self-efficacy as a mediator of sustainability knowledge, attitudes, and behavior among university students in Southwestern Nigeria: a structural equation modeling approach

Introduction This study investigated the mediating impact of environmental self-efficacy in the relationships among sustainability knowledge, sustainability attitudes, and sustainability behaviour among university students in southwestern Nigeria. Grounded in Bandura's Social Cognitive Theory (SCT), the study examined how sustainability knowledge and attitudes translate into behaviour. Methods The study adopted a quantitative, cross-sectional research design. We collected data using the Environmental Self-Efficacy Scale (ESE-10) and the Sustainability Consciousness Questionnaire (SCQ). A total of 251 valid responses were analysed using structural equation modelling (SEM) with maximum likelihood estimation and bootstrapping (5,000 resamples). Results The study found that sustainability knowledge (β = 0.104, p = 0.121) and sustainability attitude (β = 0.133, p = 0.082) had no significant direct effects on sustainability behaviour. Environmental self-efficacy exerted significant positive effects on sustainability knowledge (β = 0.568, p < 0.001), sustainability attitude (β = 0.594, p < 0.001), and sustainability behaviour (β = 0.543, p < 0.001). The specific indirect effects of sustainability knowledge (β = 0.308, 95% CI [0.198, 0.431]) and sustainability attitude (β = 0.323, 95% CI [0.211, 0.448]) on sustainability behaviour through environmental self-efficacy were significant. Moderation analysis indicated that environmental self-efficacy did not moderate the relationship between knowledge and behaviour or attitude and behaviour. Discussion These results suggest that environmental self-efficacy functions as a mediating mechanism through which sustainability knowledge and attitudes are translated into sustainability behaviour. Therefore, policy programmes aimed at promoting sustainability consciousness among university students should incorporate practical, confidence-building experiences. Also, assessment strategies should measure not only what students know and feel but also their belief in their capability.