Extending the theory of planned behavior with environmental concerns: a meta-analytic structural equation modeling of electric vehicle adoption intention

Electric vehicles (EVs) are increasingly recognized as a solution for reducing carbon emissions in the transportation sector. However, empirical findings on EV adoption based on the Theory of Planned Behavior (TPB) remain inconsistent, particularly regarding the role of environmental concern. This study addresses these inconsistencies using a random-effects meta-analysis combined with meta-analytic structural equation modeling (MASEM). Effect size analysis across ten relationship pairs shows consistently strong positive correlations, and MASEM is applied to compare the original TPB, the sub-extended TPB, and the extended TPB. The results indicate that the extended TPB provides the strongest explanatory power for adoption intention. Attitude is the most influential predictor, followed by subjective norms and perceived behavioral control, while environmental concern has a positive indirect effect. National culture also moderates these relationships, helping explain cross-study variations. Although the findings should be interpreted with caution due to data limitations and the relatively limited number of studies, this research represents one of the first meta-analytic applications of TPB in the context of EV adoption, providing a more comprehensive and robust synthesis of prior evidence.