Psychometric adaptation of the Driving Anger Expression Inventory in a Spanish sample: Differences by age and gender

The present study examined the psychometric properties of the Driving Anger Expression Inventory (DAX) (Deffenbacher, Lynch, Oetting, & Swaim, 2002) in a Spanish sample of 432 drivers. Confirmatory factor analysis showed a good fit of five factors: Verbal Aggressive Expression (α = .91), Personal Physical Aggressive Expression (α = .79), Use the Vehicle to Express Anger (α = .82), Displaced Aggression (α = .78), and Adaptative/Constructive Expression (α = .81). Direct aggressive forms of expressing anger were summed into Direct Aggressive Expression Index (α = .89), so DAX resulted in three global indices: Direct Aggressive Expression Index, Displaced Aggression, and Adaptative/Constructive Expression. All the aggressive forms correlated positively with each other and with driving anger trait, and negatively with the adaptative way of expressing anger, which support the concurrent validity of the questionnaire. There was no significant interaction effect between age and gender in the way of expressing anger nor a significant effect by gender. However, younger drivers scored higher than older in all the aggressive ways of expressing anger: Verbal Aggressive Expression (η2 = .08), Physical Aggressive Expression (η2 = .05), Use the Vehicle to Express Anger (η2 = .06), Displaced Aggression (η2 = .05), and the Direct Aggressive Expression Index (η2 = .09).

► Driving anger trait and its measurement.
► Driving anger expression and its assessment.
► Individual differences by gender and age.