Strategizing sustainable freight transport: structural insights and prioritization among economic, social, and environmental pillars

Sustainable freight transport has become a critical priority for achieving global environmental, economic, and social development goals. While previous research has examined individual sustainability dimensions, limited attention has been given to the structural interrelationships among economic, social, and environmental pillars within freight systems. This study addresses this gap by analyzing the structural dynamics of the Sustainable Freight Transport (SFT) index using a structured 4C analytical framework comprising clustering, classification, confirmatory modeling, and contextual prioritization. Cross-sectional data are analyzed using a four-stage analytical pipeline combining expectation–maximization clustering, Bayesian network tree-augmented naïve Bayes classification, partial least squares path modeling, and importance–performance map analysis. The results show that the environmental and economic pillars are the primary drivers of sustainable freight performance, with the environmental dimension emerging as the strongest determinant. Although the social pillar exerts a weaker direct influence, it plays an important mediating role by transmitting the effects of economic and environmental improvements to overall SFT outcomes. Importance–performance analysis further identifies key leverage points at both the pillar and category levels, particularly in air pollution control, climate mitigation, infrastructure quality, and service reliability. This study advances theoretical understanding by empirically revealing the structural architecture of freight sustainability and contributes methodologically by introducing a replicable 4C analytical framework for composite index analysis. The findings provide practical guidance for prioritizing strategic interventions, offering a roadmap for policymakers and industry leaders seeking to strengthen sustainable freight systems.