Truck drivers’ self-reported engagement in overloading: An application of the extended theory of planned behavior

Abstract

The aim of this study is to identify the psycho-social determinants of truck overloading from a behavioral perspective. Although there has been sizable efforts to investigate overloading from different perspectives, factors influencing truck drivers’ decisions to overload have not been revealed. In this study, sampling 552 truck drivers, we used the theory of planned behavior (TPB), extended with risk perception (RP), facilitating circumstance (FC) and law enforcement knowledge (LEK), as a lens to examine overloading. A survey questionnaire was designed to collect data, including information regarding drivers’ demographics and TPB variables. The results showed strong support for the application of the TPB in explaining overloading behavior. Specifically, behavioral intentions (BI) had the greatest direct positive effect on overloading behavior, followed by LEK, while perceived behavioral control had no direct positive effect. Interestingly, subjective norms had a significant positive effect on BI, while attitudes had a positive indirect effect, indicating that drivers’ negative attitudes toward overloading could not alone reduce this risky violation. Furthermore, all extended TPB variables were significantly and positively associated with overloading intentions, with FC having the largest positive effect. Finally, these findings were discussed in view of determining how to make truck drivers less inclined to overload.