Scale to measure motives for car use and personal norms for reducing car use in the metropolitan area of the Valley of Mexico

The motives for car use and the personal norms for reducing car use have been studied to understand the motivational processes underlying car use. Motives have been classified as instrumental, symbolic and affective, while personal norms have been classified as introjected and integrated. The aim of this study is to validate scales measuring motives for car use and personal norms for car use reduction in Mexico City. Both scales were applied, together with a measure of car use, to a sample of 257 motorists. The results indicate a good fit for the three-factor model for the motives for car use scale and a good fit for the two-factor model for personal norms for car use reduction. A linear regression model was run, which showed that both constructs explain 21.3% of variance in car use, and the significant predictors are instrumental motives and integrated norms. Both scales show initial evidence of reliability, validity and parsimony.