Transportation Research Part F Traffic Psychology and Behaviour

These secondary analyses were conducted to identify predictors of self-rated driving ability over three years in community-dwelling older adults. From the Staying Keen in Later Life (SKILL) study, baseline and 3-year follow-up data for 426 older drivers were analyzed. Health, visual, physical, psychological and cognitive abilities were examined as prospective predictors of self-rated driving ability over a 3-year period, controlling for baseline self-rated driving. Results indicated that lower baseline ratings of self-efficacy and a diagnosis of osteoporosis independently predicted lower self-rated driving ability at 3-year follow-up. Interestingly, functional performance, such as visual, physical and cognitive abilities, were not predictive of self-ratings of driving ability across three years. Older drivers' self-ratings are more reflective of perceived self-efficacy rather than functional abilities. Self-screening tools for older drivers may be effective in improving the correspondence between perceived ability and actual ability in order to promote better informed decisions about driving regulation.

Novice drivers (teen drivers with their solo license for six months or less) are at a greatly inflated risk of crashing. Post hoc analyses of police accident reports indicate that novice drivers fail to anticipate hazards, manage their speed, and maintain attention. These skills are much too broadly defined to be of much help in training. Recently, however, driving simulators have been used to identify those skills which differentiate the novice drivers from older, more experienced drivers in the areas of hazard anticipation and speed management. Below, we report an experiment on a driving simulator which compares novice and experienced drivers' performance in the third area believed to contribute especially heavily to crashes among novice drivers: attention to the forward roadway. The results indicate that novice drivers are much more willing to glance for long periods of time inside the vehicle than are experienced drivers. Interestingly, the results also indicate that both novice and experienced drivers spend equal amounts of time glancing at tasks external to the vehicle and in the periphery. Moreover, just as a program has been designed to train the scanning skills that clearly differentiate novice from experienced drivers, one might hope that a training program could be designed to improve the attention maintenance skills of novice drivers. We report on the initial piloting of just such a training program. Finally, we address a question that has long been debated in the literature: Do the results from driving simulators generalize to the real world? We argue that in the case of hazard anticipation, speed management, and attention maintenance the answer is yes.

Older drivers are known to look less often for hazards when turning at T-intersections or at four way intersections. The present study is an extension of Romoser & Fisher (2009) and attempts to further analyze the differences in scanning behavior between older and experienced younger drivers in intersections. We evaluated four hypotheses that attempt to explain the older drivers' failure to properly scan in intersections: difficulty with head movements, decreases in working memory capacity, increased distractibility, and failure to recall specific scanning patterns. To test these hypotheses, older and younger experienced drivers' point-of-gaze was monitored while they drove a series of simulated intersections with hidden hazards outside of the turning path. Our results suggest that none of these hypotheses can fully explain our finding that older adults are more likely to remain fixated on their intended path of travel and look less than younger drivers towards other areas where likely hazards might materialize. Instead, the results support a complementary hypothesis that at least some of the difficulties older adults have scanning intersections are due to a specific attentional deficit in the older drivers' ability to inhibit what has become their prepotent goal of monitoring the vehicle's intended path of travel, thereby causing older drivers to fail to scan hazardous areas outside this intended path of travel.

Driver distraction inside and outside the vehicle is increasingly a problem, especially for younger drivers. In many cases the distraction is associated with long glances away from the forward roadway. Such glances have been shown to be highly predictive of crashes. Ideally, one would like to develop and evaluate a training program which reduced these long glances. Thus, an experiment was conducted in a driving simulator to test the efficacy of a training program, FOCAL, that was developed to teach novice drivers to limit the duration of glances that are inside the vehicle while performing an in-vehicle task, such as looking for a CD or finding the 4-way flashers. The test in the simulator showed that the FOCAL trained group performed significantly better than the placebo trained group on several measures, notably on the percentage of within-vehicle glances that were greater than 2, 2.5, and 3 s. However, the training did not generalize to glances away from the roadway (e.g., when drivers were asked to attend to a sign adjacent to the roadway, both trained and untrained novice drivers were equally likely to make especially long glances at the sign).

The increasing number of hybrid and quiet internal combustion engine vehicles may impact the travel abilities of pedestrians who are blind. Pedestrians who rely on auditory cues for structuring their travel may face challenges in making crossing decisions in the presence of quiet vehicles. This article describes results of initial studies looking at the crossing decisions of pedestrians who are blind at an uncontrolled crossing (no traffic control) and a light controlled intersection. The presence of hybrid vehicles was a factor in each situation. At the uncontrolled crossing, Toyota hybrids were most difficult to detect but crossing decisions were made more often in small gaps ended by a Honda hybrid. These effects were seen only at speed under 20 mph. At the light controlled intersection, parallel surges of traffic were most difficult to detect when made up only of a Ford Escape hybrid. Results suggest that more controlled studies of vehicle characteristics impacting crossing decisions of pedestrians who are blind are warranted.

This study examined if individuals who are at increased risk for drowsy-driving because of obstructive sleep apnea syndrome (OSAS), have impairments in driving performance in the moments during microsleep episodes as opposed to during periods of wakefulness. Twenty-four licensed drivers diagnosed with OSAS based on standard clinical and polysomnographic criteria, participated in an hour-long drive in a high-fidelity driving simulator with synchronous electroencephalographic (EEG) recordings for identification of microsleeps. The drivers showed significant deterioration in vehicle control during the microsleep episodes compared to driving performance in the absence of microsleeps on equivalent segments of roadway. The degree of performance decrement correlated with microsleep duration, particularly on curved roads. Results indicate that driving performance deteriorates during microsleep episodes. Detecting microsleeps in real-time and identifying how these episodes of transition between wakefulness and sleep impair driver performance is relevant to the design and implementation of countermeasures such as drowsy driver detection and alerting systems that use EEG technology.

Gigerenzer [Gigerenzer, G. (2004). Dread risk, September 11, and fatal traffic accidents. Psychological Science, 15, 286–287] argued that the increased fear of flying in the U.S. after September 11 resulted in a partial shift from flying to driving on rural interstate highways, with a consequent increase of 353 road traffic fatalities for October through December 2001. We reevaluated the consequences of September 11 by utilizing the trends in road traffic fatalities from 2000 to 2001 for January through August. We also examined which road types and traffic participants contributed most to the increased road fatalities. We conclude that (1) the partial modal shift after September 11 resulted in 1018 additional road fatalities for the three months in question, which is substantially more than estimated by Gigerenzer, (2) the major part of the increased toll occurred on local roads, arguing against a simple modal shift from flying to driving to the same destinations, (3) driver fatalities did not increase more than in proportion to passenger fatalities, and (4) pedestrians and bicyclists bore a disproportionate share of the increased fatalities.

On September 1st 1993, a new law came into effect in Sweden, permitting instructor-supported driving practice from the age of 16 instead of 17 years and 6 months. The intention was to enable young people to gain more experience of driving a car before they acquire a driver's permit and thereby to reduce their accident risk.The study was conducted by means of a questionnaire posted to 601 17-year-olds throughout Sweden. The participants were analysed concerning gender, socio-economic standing (blue-collar and white-collar), and lifestyle (friend-oriented, externally-oriented and parent-oriented). The results show that men obtain a learner's permit more often than women (67.4% vs 57.2%) and that youngsters in white-collar families acquire a learner's permit in more cases than those in blue-collar families (67.4% vs 52.4%). One of the reasons for the latter group not acquiring a permit is that they cannot afford it, while children in white-collar families state that they have neither the time nor the desire. No significant difference was found between the three lifestyle groups.When it comes to the amount of practice, the men have been out on the road on average 39.9 h during their first 13 months, compared to 19.9 h for the women. In the lifestyle groups, those who belong to the so-called externally-oriented lifestyle have practised most. They have reported 39.2 h compared to the parent-oriented group with the least amount of training, 27.9 h on average. The friend-oriented group has 22.2 h of practice.When both lifestyle and socio-economic standing were considered, even greater differences were found. The white-collar group of the externally-oriented lifestyle reported as much as 51.5 h, compared to the blue-collar group of the parent-oriented lifestyle with only 18.4 h of practising.The above result is important because it is not in accordance with the intentions of the new driving practice system. The idea behind the new system was that all young people should have the opportunity for a longer period of driving practice in order to reduce the high accident risk during the first year with a driver’s license. If it is impossible for certain groups of youngsters to start their driving practice at the age of 16, the situation will become socially unjust and measures must be taken to remedy this situation.

Eye-movement measures were found to be highly sensitive to the demands of visual and auditory in-vehicle tasks as well as driving task demands. Two newer measures, Percent road centre and Standard deviation of gaze, were found to be more sensitive, more robust, more reliable, and easier to calculate than established glance-based measures. The eye-movement measures were collected by two partners within the EU project HASTE to determine their sensitivity to increasingly demanding in-vehicle tasks by means of artificial, or surrogate, In-vehicle Information Systems (S-IVIS). Data from 119 subjects were collected from four routes: a motorway in real traffic with an instrumented vehicle, a motorway in a fixed base simulator, and from rural roads in two different fixed base simulators. As the visual task became more difficult, drivers looked less at the road centre area ahead, and looked at the display more often, for longer periods, and for more varied durations. The auditory task led to an increasing gaze concentration to road centre. Gaze concentration to the road centre area was also found as driving task complexity increased, as shown in differences between rural curved- and straight sections, between rural and motorway road types, and between simulator and field motorways.

The present study examined the association between selected demographic variables and community-related mobility of Finnish elderly citizens. A mail survey was sent to 2500 Finnish citizens aged 65 and over. The overall response rate was 62%. Mobility was measured in two dimensions: overt travel behaviour and unfulfilled travel needs. Several demographic variables had a clear association with both dimensions of mobility. Sub-groups with reduced mobility included women, rural residents, the oldest old, and those without a driver license. When the interactions of single demographic variables were controlled for, significant predictors for hindered mobility were absence of driver license and rural-type residing. The results indicate that the level of mobility varies among the elderly, and there are certain sub-groups with limited mobility, often those with less overall resources. The possibility to drive a private car is, at present, crucial for older persons' mobility, which has important implications both for further research and policy discussion.

The present study used a mail survey addressed to Swedish drivers aged between 55 and 92 years (n=939) to study the relationship between driving exposure, health, and four types of self-reported aberrant driving behaviour as measured with a Swedish version of the driver behaviour questionnaire.Age and gender were the most important predictors of the tendency to sometimes avoid driving. However, even after accounting for age and gender, reports of own erroneous driving behaviour because of inattention (e.g., failure to notice a signal) and inexperience errors (viz., handling the car), as well as impaired health, were related to self-imposed driving limitations, whereas the violations and mistakes factors were not. Problems with activities of daily living were only marginally associated with self-imposed driving limitations, mediated through inattention and inexperience errors.The results support the notion that older drivers adjust their driving in response to their health and to the problems they experience while driving.

Research using the driver behaviour questionnaire (DBQ) has found that aberrant driving behaviours can be categorised into: errors, lapses and violations (and aggressive violations, depending on the version of the DBQ used). There is also extensive evidence that it is only the `violations' score which is significantly correlated with, and predictive of, crash involvement. This consistency has been found both across different samples and different countries. However, recent research conducted on those driving cars in a work-related context has found a different factor structure and a different pattern of correlations with crash involvement. The present study extends this research by investigating the factor structure of the DBQ and the relationship between aberrant driving behaviour and crash involvement for a sample of truck drivers. Factor analysis yielded a four factor solution, that broadly replicated the four hypothetical factors (errors, lapses, violations and aggressive violations) found in the general driving population. Only the violations factor was found to be significantly predictive of crash involvement. This research provides evidence of the robust nature of the DBQ findings in populations other than the drivers of private motor vehicles.

Moped riders, particularly youngsters, are amongst the highest risk group in traffic. We used an adapted version of the Driver Behaviour Questionnaire to examine why moped riders are often involved in traffic accidents. We conducted a questionnaire study among 146 young moped riders in the Netherlands. We found that aberrant behaviour of moped riders can indeed be classified as errors, lapses, and violations. Accidents involvement appeared not to be significantly related to errors, lapses, and violations. As hypothesised, moped riders were more likely to speed, and had a stronger intention to disobey speed limits when they have a positive attitude towards speeding, and when they think that others expect them to speed. Perceived control did not affect self-reported speeding and intention to speed. We discuss the theoretical and practical implications of our study.

This study reports an experiment that compared the hazard perception abilities of experienced and novice motorcycle riders using an interactive, closed-loop, simulator. Participants (n = 49) were categorized into four groups: experienced motorcycle riders with full driver licence, inexperienced motorcycle riders with full driver licence, novice motorcycle riders with full driver licence, and novice motorcycle riders with probationary driver licence. The participants were tested on three scenarios, each consisting of eight hazardous events. They were instructed to ride normally, but to respond appropriately to avoid the hazards. Under certain conditions in the simulator, we found that experienced riders (relative to inexperienced or novice riders) crashed less often, received better performance evaluations, and approached hazards at more appropriate speeds. Interestingly, we also found that some novice riders were overconfident in their riding ability. We discuss how this overconfidence might be related to hazard perception.

The present paper describes a study that aims at assessment of driver behaviour in response to new technology, particularly Adaptive Cruise Control Systems (ACCs), as a function of driving style. In this study possible benefits and drawbacks of Adaptive Cruise Control Systems (ACCs) were assessed by having participants drive in a simulator. The four groups of participants taking part differed on reported driving styles concerning Speed (driving fast) and Focus (the ability to ignore distractions), and drove in ways which were consistent with these opinions. The results show behavioural adaptation with an ACC in terms of higher speed, smaller minimum time headway and larger brake force. Driving style group made little difference to these behavioural adaptations. Most drivers evaluated the ACC system very positively, but the undesirable behavioural adaptations observed should encourage caution about the potential safety of such systems.

This test-track study assessed whether adaptive cruise control (ACC) induces behavioural adaptation in drivers. Eighteen experienced drivers drove a test vehicle while following a lead vehicle in three counterbalanced conditions: No ACC (self-maintained average headway of 2 s), ACC-Short (headway of 1.4 s) and ACC-Long (headway of 2.4 s). Results demonstrate that ACC can induce behavioural adaptation in drivers in potentially safety-critical ways. Compared to driving unsupported, participants located significantly more items per minute on a secondary task when using ACC, while their response times to a hazard detection task increased. This effect was particularly pronounced in those scoring high on a sensation-seeking scale. Using ACC resulted in significantly more lane position variability, an effect that was also more pronounced in high sensation-seekers. Drivers' trust in ACC increased significantly after using the system, and these ratings did not change despite a simulated failure of the ACC system during the ACC-Long condition. Response time to the simulated ACC failure was related to a driver's locus of control: Externals intervened more slowly than Internals. All drivers reported relying on the ACC system to keep their vehicle at a safe distance from the lead vehicle. Results are consistent with similar research conducted on lane departure warning systems. Driver awareness training is a potential preventive strategy that could minimize the behavioural adaptation associated with novel in-vehicle systems such as ACC.

This study aimed to model driver’ deceleration or acceleration rates on a complex two-lane rural highway when approaching or departing horizontal curves under nighttime driving conditions. The data used in the study were from a field experiment conducted in Pennsylvania. Research participant speeds were continuously tracked along the experimental roadway. The deceleration and acceleration rate models when approaching and departing horizontal curves were treated as a uni-directional recursive system to account for the effects of upstream rates on deceleration and acceleration rates. This system was estimated using seemingly unrelated regression with random effects to account for the contemporaneous correlation across the two equations. Research participants were included in the model as random effects while several geometric roadway design features along the experimental roadway were included as fixed effects in the model. The results indicate that the explanatory variables associated with deceleration or acceleration rates when approaching or departing horizontal curves in the present experiment included several geometric design variables, such as curve direction, curve radius, horizontal curve length, and a vertical curve index. The deceleration and acceleration rates approaching and departing horizontal curves along the complex, two-lane rural highway included in this study have a larger range than those in past research studies of two-lane rural highways.

The long-term effects of driving with an active accelerator pedal on driver behaviour were studied by using an in-car observation method over the period beginning 2000 until 2001. The system produced a counterforce in the accelerator pedal when the speed limit was reached, but could be overridden by pressing the accelerator pedal harder. Twenty-eight drivers were studied when driving without the system and then when driving with the system after they had used it in their own cars for at least six months. The results showed that their behaviour towards other road users improved, they had a yielding behaviour correct to a higher degree and were more likely to give pedestrians the right of way at zebra crossings when driving with the active accelerator pedal. It was also found that the time gap to the vehicle in front increased slightly with the system. There were also signs of negative behavioural modifications in the form of drivers forgetting to adapt their speed to the speed limit or the prevailing traffic situation when they were not supported by the system and in low speed areas; these effects, however, were not statistically significant. Together with studies showing improved speed behaviour, the results of this study augur well for great safety effects of the system.

The Intelligent Speed Adapter (ISA) is an example of in-car telematics equipment that is developed to reduce speeding. It can be introduced as a policy instrument to improve speed limit compliance and with that traffic safety. However, previous research indicated that acceptability of this type of instruments is rather limited. Adopting a policy that may increase acceptability before introduction of the instrument is therefore recommended. To formulate such a policy, understanding the factors that influence ISA acceptability is required. To that effect, a causal model that disentangles the direct and indirect effects of predictor variables on ISA acceptability is developed and estimated. The model includes car drivers’ attitudes, opinions and beliefs on the speeding problem, the policy goal and the policy instrument ISA, as well as speed related behaviour and socio-demographic variables. This paper presents the direct and total effects of these variables on ISA acceptability. The results suggest that explaining clearly how ISA can contribute to attaining various personal and societal goals may be a viable policy to increase ISA acceptability.

A key success factor in the future implementation of new in-vehicle technologies is in understanding how users will experience and respond to these devices. Although it is recognized that acceptance, acceptability and/or support is important, consistency in the definition of acceptability, and how it can be measured, is absent. In this paper we conceptualize acceptance as the attitudes towards a new device after its introduction and acceptability as the attitudes to it before its introduction. It is our goal to describe and conceptualize the most common and relevant socio-psychological factors that can influence acceptance and acceptability of Intelligent Speed Adaptation (ISA). By analysing the different theories and methods used in ISA trials we arrived at the 14 most potential indicators that could influence the definition of acceptability and acceptance. A test survey was conducted to determine if these indicators are relevant and if they affect acceptability. The use of a factor analysis helped to single out those questions that were deemed relevant in doing our conceptual acceptability analysis, and to allocate correlations between the different items. We conclude that we have found a concept with some main possible indicators that directly influence the acceptability of ISA.

Rural stop-controlled intersections pose a crash risk for drivers turning or crossing the intersection from the minor road. In particular, elderly drivers are at the highest risk of a collision in this situation. Errors made during gap detection, perception and acceptance are the main factors that influence crashes at this type of intersection. This study investigated young (20–40 years) and old (55–75 years) drivers’ gap acceptance performance in simulated day and night driving conditions in a Baseline condition (STOP sign only) and four intersection decision support (IDS) conditions. The four IDS conditions were initial infrastructure-based design concepts that provided varying levels of dynamic information about traffic conditions on the major road to crossing minor-road drivers. Signs that provided detailed gap information (i.e., time-to-arrival values, warning levels for gaps) as well as advisory information about unsafe conditions resulted in the best performance among old and young drivers in comparison to signs that did not provide specific gap-related information (i.e., detected vehicles approaching, but not size of gap or safety of gap). Comprehension, acceptance and usability ratings of the IDS signs were also highest for signs providing detailed gap and advisory information on the same sign. Recommendations for further design and development of the IDS system interface based on driver performance and acceptance of the technology is discussed.

In-vehicle systems that assist the driver with his driving task are developed and introduced to the market at increasing rate. Drivers may be supported during congested traffic conditions by a so-called Congestion Assistant consisting of a mix of informing, assisting and controlling functions. This paper describes the impacts of the Congestion Assistant on the driver in terms of driving behaviour and acceptance. Thirty-seven participants took part in a driving simulator study. The observed driving behaviour showed promising improvements in traffic safety when approaching the traffic jam. Moreover, positive effects of the system on traffic efficiency can be expected in the jam. The participants stated to appreciate the Congestion Assistant, although not all functions were equally rated. To increase the performance and acceptance of the total system, some refinements were suggested.

Every year, more than 500 people are killed on the roads in Israel and more than 3000 are seriously injured. The most dominant factor in understanding the chain of events leading to an accident is the human factor, and understanding driver’s perceptions of the issue are necessary for interventions to be effective. Internet “talk-backs” to accident news items were used as an innovative data source in the present content analysis. In contrast to other qualitative techniques, such as focus groups or interviews, the debate is spontaneous and open to a large audience. The aim of this study was to provide structured and in-depth information about road users’ attitudes and beliefs towards road accidents and their prevention. The total number of “talk-backers” during the 4 months analyzed was 2095. The driver’s behavior as the cause of accidents constitutes the most frequently mentioned theme in the “talk-backs”, more than the themes regarding the condition of the vehicle or the road infrastructure. The driver’s behavior theme was further divided into sub-categories such as driving skills, traffic rule violations, aggressive driving and uncivilized behavior. Lay people were also able to suggest prevention strategies, such as policy, enforcement, road infrastructure, and sanctioning. This information may assist policy-makers and safety experts in identifying the appropriate means of intervention, implementation and communication with the public.

This study aimed to investigate the relationship between age, gender, and risky behaviors of motorcyclists and their involvement in accidents. The results of a self-reported survey on motorcyclist behavior in the Taipei metropolitan area were analyzed. A two-step cluster analysis was used to classify motorcyclist behavior to different levels of risk within each of three risky behavior types. This was used to examine the regression relationship with accident risk. The results indicated that young and male riders were more likely to disobey traffic regulations, and that young riders also had a higher tendency towards negligence of potential risk and motorcycle safety checks. These “error” and “violation” behaviors increased the likelihood of an accident. However, in addition to these risks, there are additional factors that put young riders, particularly young female riders with the least riding experience, at increased risk of having an accident. These additional factors may be poor driving skills and less experience, all of which may result from the slack motorcycle licensing system. There should be increased emphasis on the necessity of providing appropriate training and a lower risk environment for novice riders.