Multigroup invariance of the DAS across a random and an internet-sourced sample

Area of Science:

• Psychology
• Road Safety Research
• Survey Methodology

Background:

• Driver anger and aggression are significant road safety concerns.
• The Driving Anger Scale (DAS) is a key instrument for measuring driver anger.
• Internet-based data collection is increasingly common but its validity for driving research requires confirmation.

Purpose of the Study:

• To investigate the psychometric invariance of the Driving Anger Scale (DAS) between traditional and internet-sourced samples.
• To determine if online data collection methods impact the measurement of driver anger.

Main Methods:

• Multigroup Confirmatory Factor Analysis (MGCFA) was employed.
• Two distinct samples were compared: a random electoral roll sample (N=1,081) and an internet-sourced sample (N=627).
• The invariance of the six-factor DAS structure was tested across these samples.

Main Results:

• The six-factor structure of the DAS was supported in both the electoral roll and internet samples.
• Relationships between DAS factors and demographic variables (age, sex, trait anger, mileage) were broadly similar across samples.
• Some statistically significant differences were noted in the internet sample, but overall invariance was demonstrated.

Conclusions:

• Internet-administered driving measures, including the DAS, produce results comparable to traditional methods.
• Online data collection is a valid and reliable approach for driving anger research.
• This supports the continued use of online methodologies for convenience and broader reach in road safety studies.