Shedding light on the psychological and behavioral determinants of travel mode choice: A meta-analysis

- Intentions, habits and past use represent the main predictors of travel mode choice.
- Attitudes, social norms and behavioral control also predict modal choice.
- Environmental variables predict behavioral intentions but not actual behaviors.
- There is a high heterogeneity across different studies.
- Behaviors' operationalization and measurement is the main moderator.

Mobility represents a relevant topic from the standpoint of environmental degradation, health-related consequences and social inclusion. Since private mobility is responsible for the greatest share of polluting emissions, it is necessary to gain deeper understanding of the mechanisms underpinning the choice of individuals to use either cars or alternative, environment-friendly transport modes. A meta-analysis on 58 primary studies is conducted to synthesize evidence on the determinants of travel mode choice, as regards both behavioral intentions and actual behaviors. Results suggest that, besides intentions, habits and past use represent the most relevant predictor, followed by constructs referring to the Theory of Planned Behavior framework. Environmental variables, on the other hand, play a relevant role in shaping behavioral intentions while their effect on actual behaviors is negligible, so that a deep intention behavior gap emerges. A moderator analysis is performed to explain the high heterogeneity in the results. Behaviors' operationalization and measurement emerges as the moderator affecting heterogeneity of outcomes the most; trip purpose, sample type and year of the study also show a moderate effect on heterogeneity, while location does not appear to be a relevant moderator.