Mark Wetton

Hazard perception in novice and experienced drivers: The effects of sleepiness

One driver skill that has been found to correlate with crash risk is hazard perception ability. The purpose of this study was to investigate how hazard perception latencies change between high and low sleepiness for a high risk group (novice drivers) and a lower risk group (experienced drivers). Thirty-two novice drivers (aged 17-24 years) and 30 experienced drivers (aged 28-36) completed a validated video-based hazard perception test, in which participants were asked to anticipate genuine traffic conflicts in footage filmed from the drivers perspective, with separate groups tested at either 10a.m. (lower sleepiness) or at 3a.m. (higher sleepiness). We found a significant interaction between sleepiness and experience, indicating that the hazard perception skills of the more experienced drivers were relatively unaffected by mild increases in sleepiness while the inexperienced drivers were significantly slowed. The findings suggest that the disproportionate sleepiness-related accident involvement of young, inexperienced drivers could be partly due to a slowing of their ability to anticipate traffic hazards.

The development and validation of two complementary measures of drivers’ hazard perception ability

Hazard perception in driving involves a number of different processes. This paper reports the development of two measures designed to separate these processes. A Hazard Perception Test was developed to measure how quickly drivers could anticipate hazards overall, incorporating detection, trajectory prediction, and hazard classification judgements. A Hazard Change Detection Task was developed to measure how quickly drivers can detect a hazard in a static image regardless of whether they consider it hazardous or not. For the Hazard Perception Test, young novices were slower than mid-age experienced drivers, consistent with differences in crash risk, and test performance correlated with scores in pre-existing Hazard Perception Tests. For drivers aged 65 and over, scores on the Hazard Perception Test declined with age and correlated with both contrast sensitivity and a Useful Field of View measure. For the Hazard Change Detection Task, novices responded quicker than the experienced drivers, contrary to crash risk trends, and test performance did not correlate with measures of overall hazard perception. However for drivers aged 65 and over, test performance declined with age and correlated with both hazard perception and Useful Field of View. Overall we concluded that there was support for the validity of the Hazard Perception Test for all ages but the Hazard Change Detection Task might only be appropriate for use with older drivers.

Improving older drivers' hazard perception ability.

One reason that older drivers may have elevated crash risk is because they anticipate hazardous situations less well than middle-aged drivers. Hazard perception ability has been found to be amenable to training in young drivers. This article reports an experiment in which video-based hazard perception training was given to drivers who were between the ages of 65 and 94 years. Trained participants were significantly faster at anticipating traffic hazards compared with an untrained control group, and this benefit was present even after the authors controlled for pretraining ability. If future research shows these effects to be robust, the implications for driver training and safety are significant.

The effects of driving experience on responses to a static hazard perception test.

Novice drivers exhibit deficits in hazard perception that are likely to increase their risk of collisions. We developed a static hazard perception test that presents still images to observers and requires them to indicate the presence of a traffic conflict that would lead to a collision. Responses to these scenes were obtained for young adult novice (N=29) and experienced drivers (N=27). Additionally, participants rated the hazard risk and clutter of each scene. Novice drivers rated traffic conflicts as less hazardous and responded more slowly to them. Using a subset of 21 scenes, we were able to discriminate novice and experienced young adult drivers with a classification accuracy of 78% and a scale reliability (Cronbachs alpha) of .91. The potential applications of this research include the development of standardized hazard perception tests that can be used for driver evaluation, training and licensure.

A brief office-based hazard perception intervention for drivers with ADHD symptoms

Objective: The aim of this study was to develop a simple and brief hazard perception training intervention tailored to meet the needs of male drivers with attention-deficit-hyperactivity disorder symptoms. Methods: Twenty male drivers with attention-deficit-hyperactivity disorder symptoms were quasi-randomly assigned to either a hazard perception training package (trained group) or a control intervention video (untrained group), presented in an office setting. Video-based hazard perception tests involving real-life driving scenes were conducted both before and after the interventions. Results: The hazard perception response times of the trained group significantly improved compared with the untrained group, t (18) = 3.21, p < 0.005. Conclusions: Significant improvements in hazard perception response times in male drivers with attention-deficit-hyperactivity disorder symptoms were found following the training intervention. This indicates that such training has potential for inclusion in a management plan for reducing the crash rates of this high risk group of drivers. The training is practical, quick, and affordable, and has the potential to translate into real-world driving outcomes.

Can a video-based hazard perception test used for driver licensing predict crash involvement?

In 2008, the state of Queensland in Australia introduced a video-based hazard perception test as part of the licensing process for new drivers. A key validity check for such a test is whether scores are associated with crash involvement. We present data demonstrating that drivers who failed the hazard perception test (based on a ROC curve-derived pass mark) were 25% [95% confidence interval (CI) 6%, 48%] more likely to be involved in an active crash (defined as a crash occurring while the drivers vehicle was moving but they were not engaged in parking or reversing) during a one year period following the test (controlling for driving exposure, age, and sex). Failing drivers were also 17% (95% CI 6%, 29%) more likely to have been involved in active crashes prior to the test, in the period since obtaining their provisional license. These data support the proposal that the hazard perception test is a valid measure of crash-related driving performance.

The Longer-Term Effects of a Brief Hazard Perception Training Intervention in Older Drivers

Previous research has shown that drivers aged over 65 years can improve their scores in video-based hazard perception tests following training interventions. In order to examine the longer-term effects of hazard perception training, we recruited 75 drivers aged 65 and over. They either received a 35-min hazard perception training intervention or a placebo intervention. Significant decreases in hazard perception response time as a result of the training were found immediately after the intervention, and approximately 1 month and 3 months later. There was no significant decay in the training effect over this time period.