What happens next? Predicting other road users' behaviour as a function of driving experience and processing time.

Hazard perception is one of the most important facets of driving and if the appropriate diagnostic tool is used it can discriminate between novice and experienced drivers. In this study video clips of actual driving scenarios were shown to novice and experienced drivers. The clips were stopped just prior to hazard onset and either the screen went black or the final still image stayed on the screen. Participants were then asked five questions about what happened next. This variant of the hazard perception test allowed the influence of processing time to be included and the level of situation awareness to be measured. Experienced drivers significantly anticipated more correct hazardous outcomes than novice drivers when the screen went black. Novice drivers benefited from the extra processing time afforded by the image remaining on the screen and significantly anticipated more hazards when the image remained on the screen than when it went black. The findings indicate that when processing time is manipulated, hazard perception accuracy reveals experiential differences. These differences are discussed with reference to hazard perception and situation awareness. This research informs the current controversy over whether hazard perception is a good diagnostic tool for driving performance. It identifies potential confounds in previous work and demonstrates that experiential differences can be found if the appropriate tests are used. Further, it suggests improvements for new hazard perception tests.