Near peripheral motion contrast threshold predicts older drivers’ simulator performance

Our group has previously demonstrated that peripheral motion contrast threshold (PMCT) is significantly associated with self-reported accident risk of older drivers (questionnaire assessment), and with Useful Field of View^® subtest 2 (UFOV2). It has not been shown, however, that PMCT is significantly associated with driving performance. Using the method of descending limits (spatial two-alternative forced choice) we assessed motion contrast thresholds of 28 young participants (25–45), and 21 older drivers (63–86) for 0.4 cycle/degree drifting Gabor stimuli at 15° eccentricity and examined whether it was related to performance on a simulated on-road test and to a measure of visual attention (UFOV^® subtests 2 and 3). Peripheral motion contrast thresholds (PMCT) of younger participants were significantly lower than older participants. PMCT and UFOV2 significantly predicted driving examiners’ scores of older drivers’ simulator performance, as well as number of crashes. Within the older group, PMCT correlated significantly with UFOV2, UFOV3, and age. Within the younger group, PMCT was not significantly related to either UFOV^® scores or age. Partial correlations showed that: substantial association between PMCT and UFOV2 was not age-related (within the older driver group); PMCT and UFOV2 tapped a common visual function; and PMCT assessed a component not captured by UFOV2. PMCT is potentially a useful assessment tool for predicting accident risk of older drivers, and for informing efforts to develop effective countermeasures to remediate this functional deficit as much as possible.     

Near peripheral motion detection threshold correlates with self-reported failures of attention in younger and older drivers

Motion contrast thresholds for 0.4 cycle/degree drifting Gabor stimuli were assessed at 15° eccentricity in the right and left visual fields for 16 younger drivers (ages 24-42), and 15 older drivers (ages 65-84), using a temporal two-alternative forced choice staircase procedure. Two self-report questionnaires that assess failures of attention while driving—the Driver Perception Questionnaire (DPQ5), and an abridged Aging Driver Questionnaire (ADQ15)—were administered. The three UFOV^® subtests of attention and processing speed were also administered. Mean peripheral motion contrast threshold (PMCT) of older drivers was significantly higher than that of younger drivers. When controlling for age, PMCT thresholds correlated significantly with both DPQ5 and ADQ15 while the UFOV^® subtests were found not to correlate with PMCT results. The potential value of the PMCT as an assessment of drivers’ hazard detection capacity is discussed.     

Development and evaluation of a Driving Observation Schedule (DOS) to study everyday driving performance of older drivers

This paper describes the development and evaluation of an on-road procedure, the Driving Observation Schedule (DOS), for monitoring individual driving behavior. DOS was developed for use in the Candrive/Ozcandrive five-year prospective study of older drivers. Key features included observations in drivers’ own vehicles, in familiar environments chosen by the driver, with start/end points at their own homes. Participants were 33 drivers aged 75+ years, who drove their selected route with observations recorded during intersection negotiation, lane-changing, merging, low speed maneuvers and maneuver-free driving. Driving behaviors were scored by a specialist occupational therapy driving assessor and another trained observer. Drivers also completed a post-drive survey about the acceptability of DOS. Vehicle position, speed, distance and specific roadways traveled were recorded by an in-vehicle device installed in the participant's vehicle; this device was also used to monitor participants’ driving over several months, allowing comparison of DOS trips with their everyday driving. Inter-rater reliability and DOS feasibility, acceptability and ecological validity are reported here. On average, drivers completed the DOS trip in 30.48 min (SD = 7.99). Inter-rater reliability measures indicated strong agreement between the trained and the expert observers: intra-class correlations (ICC) = 0.905, CI 95% 0.747–0.965, p < 0.0001; Pearson product correlation, r (18) = .83, p < 0.05. Standard error of the measurement (SEM), method error (ME) and coefficient of variation (CV) measures were consistently small (3.0, 2.9 & 3.3%, respectively). Most participants reported being ‘completely at ease’ (82%) with the driving task and ‘highly familiar with the route’ (97%). Vehicle data showed that DOS trips were similar to participants’ everyday driving trips in roads used, roadway speed limits, drivers’ average speed and speed limit compliance. In summary, preliminary findings suggest that DOS can be scored reliably, is of feasible duration, is acceptable to drivers and representative of everyday driving. Pending further research with a larger sample and other observers, DOS holds promise as a means of quantifying and monitoring changes in older drivers’ performance in environments typical of their everyday driving.     

How accurately do drivers evaluate their own driving behavior? An on-road observational study

Self-assessment of driving skills became a noteworthy research subject in traffic psychology, since by knowing one's strenghts and weaknesses, drivers can take an efficient compensatory action to moderate risk and to ensure safety in hazardous environments. The current study aims to investigate drivers’ self-conception of their own driving skills and behavior in relation to expert evaluations of their actual driving, by using naturalistic and systematic observation method during actual on-road driving session and to assess the different aspects of driving via comprehensive scales sensitive to different specific aspects of driving. 19–63 years old male participants (N = 158) attended an on-road driving session lasting approximately 80 min (45 km). During the driving session, drivers’ errors and violations were recorded by an expert observer. At the end of the driving session, observers completed the driver evaluation questionnaire, while drivers completed the driving self-evaluation questionnaire and Driver Behavior Questionnaire (DBQ). Low to moderate correlations between driver and observer evaluations of driving skills and behavior, mainly on errors and violations of speed and traffic lights was found. Furthermore, the robust finding that drivers evaluate their driving performance as better than the expert was replicated. Over-positive appraisal was higher among drivers with higher error/violation score and with the ones that were evaluated by the expert as “unsafe”. We suggest that the traffic environment might be regulated by increasing feedback indicators of errors and violations, which in turn might increase the insight into driving performance. Improving self-awareness by training and feedback sessions might play a key role for reducing the probability of risk in their driving activity.     

Older drivers' insight into their hazard perception ability

Even though the driving ability of older adults may decline with age, there is evidence that some individuals attempt to compensate for these declines using strategies such as restricting their driving exposure. Such compensatory mechanisms rely on drivers’ ability to evaluate their own driving performance. This paper focuses on one key aspect of driver ability that is associated with crash risk and has been found to decline with age: hazard perception. Three hundred and seven drivers, aged 65–96, completed a validated video-based hazard perception test. There was no significant relationship between hazard perception test response latencies and drivers’ ratings of their hazard perception test performance, suggesting that their ability to assess their own test performance was poor. Also, age-related declines in hazard perception latency were not reflected in drivers’ self-ratings. Nonetheless, ratings of test performance were associated with self-reported regulation of driving, as was self-rated driving ability. These findings are consistent with the proposal that, whileself-assessments of driving ability may be used by drivers to determine the degree to which they restrict their driving, the problem is that drivershave little insight into their own driving ability. This may impact on the potential road safety benefits of self-restriction of driving because drivers may not have the information needed to optimally self-restrict. Strategies for addressing this problem are discussed.     

Age differences in cognitive and psychomotor abilities and simulated driving

The current study investigated the relationship between drivers’ abilities in various cognitive and psychomotor domains and their driving performance. The goal was to identify test measures that could be used to develop a fitness-for-driving test battery, particularly for older drivers. Licensed drivers over 40 years of age (M = 65.56 years, SD = 13.02) were recruited from university leisure courses (n = 18) and drivers under 40 (M = 22.20 years, SD = 3.79) were recruited from undergraduate and graduate courses (n = 44). Participants were given a battery of standard neuropsychological tests used to assess ability in the domains of cognitive processing speed, psychomotor functioning, visuospatial performance, sustained attention, and executive functioning. Participants’ driving ability was assessed in a simulator with data collected in three categories of driving performance: (a) driver control maintenance behaviors, (b) accidents and violations, and (c) attention and reaction time. Younger participants outperformed older participants in 4 out of the 5 domains of neuropsychological testing (all but sustained attention). Age differences were found in simulator driving accidents and violations and driving performance was significantly correlated with neuropsychological test performance. The results are discussed in terms of the potential to use these tests to assess older drivers seeking license renewal or for selecting professional drivers for the transportation industry.     

Elderly drivers’ everyday behavior as a predictor of crash involvement—Questionnaire responses by drivers’ family members

When or whether elderly drivers stop driving is concerning not only to the drivers themselves but also to their family members. Therefore, it is important for family members to take the initiative if they wish to obtain information on the likelihood of the drivers’ involvement in crashes. On the basis of the older drivers’ Everyday Behavior Questionnaire (EBQ) developed in this paper, we attempt to predict drivers’ involvement in crashes using the responses given by their family members. The results revealed that this 14-item questionnaire has a sufficient level of internal consistency as well as a significant correlation (r = 0.29) with the experience of involvement in crashes in the last three years (p < 0.01). Although the EBQ is a proxy-reported questionnaire and does not include items directly related to driving behaviors, the correlation between the EBQ and crash involvement is stronger than that of the self-reported Driver Behavior Questionnaire reported in deWinter and Dodou (2010), who conducted a meta-analysis and estimated the overall correlation among samples of earlier studies. In addition, logistic regression analysis showed that the EBQ score and the exposure to driving risks, measured by the frequency of driving, are significant predictors of involvement in crashes.     

Capturing the serial nature of older drivers’ responses towards challenging events: A simulator study

Older drivers’ ability to trigger simultaneous responses in reaction to simulated challenging road events was examined through crash risk and local analyses of acceleration and direction data provided by the simulator. This was achieved by segregating and averaging the simulator's primary measures according to six short time intervals, one before and five during the challenging events. Twenty healthy adults aged 25-45 years old (M = 29.5 ± 4.32) and 20 healthy adults aged 65 and older (M = 73.4 ± 5.17) were exposed to five simulated scenarios involving sudden, complex and unexpected maneuvres. Participants were also administered the Useful Field of View (UFOV), single reaction time and choice reaction time tests, a visual secondary task in the simulator, and a subjective workload evaluation (NASA-TLX). Results indicated that the challenging event that required multiple synchronized reactions led to a higher crash rate in older drivers. Acceleration and orientation data analyses confirmed that the drivers who crashed limited their reaction. The other challenging events did not generate crashes because they could be anticipated and one response (braking) was sufficient to avoid crash. Our findings support the proposal (Hakamies-Blomqvist, L., Mynttinen, S., Backman, M., Mikkonen, V., 1999. Age-related differences in driving: are older drivers more serial? International Journal of Behavioral Development 23, 575-589) that older drivers have more difficulty activating car controls simultaneously putting them at risk when facing challenging and time pressure road events.     

Revisiting the concept of the ‘problem young driver’ within the context of the ‘young driver problem’: Who are they?

For decades there have been two young driver concepts: the ‘young driver problem’ where the driver cohort represents a key problem for road safety; and the ‘problem young driver’ where a sub-sample of drivers represents the greatest road safety problem. Given difficulties associated with identifying and then modifying the behaviour of the latter group, broad countermeasures such as graduated driver licensing (GDL) have generally been relied upon to address the young driver problem. GDL evaluations reveal general road safety benefits for young drivers, yet they continue to be overrepresented in fatality and injury statistics. Therefore it is timely for researchers to revisit the ‘problem young driver’ concept to assess its potential countermeasure implications. This is particularly relevant within the context of broader countermeasures that have been designed to address the ‘young driver problem’ Personal characteristics, behaviours and attitudes of 378 Queensland novice drivers aged 17–25 years were explored during their pre-, Learner and Provisional 1 (intermediate) licence as part of a larger longitudinal project. Self-reported risky driving was measured by the Behaviour of Young Novice Drivers Scale (BYNDS), and five subscale scores were used to cluster the drivers into three groups (high risk n = 49, medium risk n = 163, low risk n = 166). High risk ‘problem young drivers’ were characterised by greater self-reported pre-Licence driving, unsupervised Learner driving, and speeding, driving errors, risky driving exposure, crash involvement, and offence detection during the Provisional period. Medium risk drivers were also characterised by more risky road use than the low risk group. Interestingly problem young drivers appear to have some insight into their high-risk driving, since they report significantly greater intentions to bend road rules in future driving. The results suggest that tailored intervention efforts may need to target problem young drivers within the context of broad countermeasures such as GDL which address the young driver problem in general. Experiences such as crash-involvement could be used to identify these drivers as a preintervention screening measure.     

How realistic are older drivers’ ratings of their driving ability?

One strategy that can be used by older drivers to guard against age-related declines in driving capability is to regulate their driving. This strategy presumes that self-judgments of driving capability are realistic. We found no significant relationships between older drivers’ hazard perception skill ratings and performance on an objective and validated video-based hazard perception test, even when self-ratings of performance on specific scenarios in the test were used. Self-enhancement biases were found across all components of driving skill, including hazard perception. If older drivers’ judgments of their driving capability are unrealistic, then this may compromise the effectiveness of any self-restriction strategies to reduce crash risk.     

Validation of selected temperament and personality questionnaires for diagnosing drivers’ aptitude for safe driving. A Polish study

This paper presents the results of a study aimed at validating psychological questionnaires evaluating temperamental and personality features. It discusses their usefulness in diagnosing drivers’ aptitude for safe driving and working as professional drivers. Three psychological questionnaires were validated: the Formal Characteristics of Behaviour – Temperament Inventory (FCB-TI), the Eysenck Personality Questionnaire – Revised and Short Scale (EPQ-R (S)) and the Impulsiveness Questionnaire (IVE). Three groups of drivers (n = 246) aged 19–75 participated in the study. Group I (professional drivers; n = 96) and Group II (nonprofessional drivers; n = 75) had never been involved in road crashes, whereas Group III (nonprofessional drivers; n = 75) were offenders involved in fatal injury road crashes. Criterion-related validity, Cronbach's alpha and Guttman split-half reliability coefficient were in assessing the psychometric properties of the questionnaires. There were some significant differences between Groups II and III for most traits. However, contrary to expectations, higher Emotional Reactivity, Perseveration and lower Endurance as well as higher Neuroticism, Impulsiveness and Venturesomeness were determined for Group II than for Group III. Additionally, the temperament and personality profile of Group II turned out to be less fitted to the profile of safe drivers than that of Group III, whose profile was actually similar to that of Group I. This seems to result from a high tendency for a positive self-presentation among Group I and Group III (a significantly higher result on the Lie scale in comparison with Group II). The results suggest that if psychological tests are to decide on whether a person may be a professional driver or may drive vehicles, the three questionnaires (FCB-TI, EPQ-R(S) and IVE) do not provide a valid diagnosis of professional drivers’ aptitude because of drivers’ high tendency for positive self-presentation. However, they can be used in job counselling and in screening high-risk drivers.     

How reinforcement sensitivity and perceived risk influence young drivers’ reported engagement in risky driving behaviors

Gray's reinforcement sensitivity theory (RST), implementing Carver and White's behavior inhibition system (BIS) and behavior approach system (BAS) scales, was used to predict reported engagement in 10 risky driving behaviors: speeding (2 levels), driving under the influence of alcohol, racing other vehicles, cell phone use (hand-held and hands free), tailgating, unsafe overtaking, driving while fatigued, and not wearing a seatbelt. Participants were 165 young male and female (n = 101) drivers aged 17–25 years who held a valid Australian driver's license. Effects of the explanatory variables and specific risk perceptions upon engagement in the reported risky driving behaviors were examined using SEM analyses. Also of interest was whether perceived risk mediated the relationship between the personality variables and reported engagement in risky driving behaviors. RST variables, negative reactivity, reward responsiveness and fun seeking, accounted for unique variance in young drivers’ perceived risk. Reward responsiveness and perceived risk accounted for unique variance in young drivers’ reported engagement in risky driving behaviors. Negative reactivity was completely mediated by perceived risk in its negative relationship with reported engagement. To better understand driving related risk decision making, future research could usefully incorporate drivers’ motivation systems. This has the potential to lead to more tailored approaches to identifying risk-prone drivers and provide information for the development and implementation of media campaigns and educational programs.     

EEG alpha spindles and prolonged brake reaction times during auditory distraction in an on-road driving study

Driver distraction is responsible for a substantial number of traffic accidents. This paper describes the impact of an auditory secondary task on drivers’ mental states during a primary driving task. N = 20 participants performed the test procedure in a car following task with repeated forced braking on a non-public test track. Performance measures (provoked reaction time to brake lights) and brain activity (EEG alpha spindles) were analyzed to describe distracted drivers. Further, a classification approach was used to investigate whether alpha spindles can predict drivers’ mental states.     

Stability of physical assessment of older drivers over 1 year

Older adults represent the fastest-growing population of drivers with a valid driver's licence. Also common in this age group are multiple chronic medical conditions that may have an effect on physical function and driving ability. Determining the reliability of physical measures used to assess older drivers’ functional ability is important to identifying those who are safe to continue driving. Most previous reliability studies of clinical physical measures of health used test–retest intervals shorter than those between patient visits with a clinician. In the present study we examined a more clinically representative interval of 1 year to determine the stability of commonly used physical measures collected during the Candrive II prospective cohort study of older drivers. Reliability statistics indicate that the sequential finger–thumb opposition, rapid pace walk and the Pelli–Robson contrast sensitivity tests have adequate stability over 1 year. Poor stability was observed for the one-legged stance and Snellen visual acuity test. Several assessments with nominal data (Marottoli method [functional neck range of motion], whispered voice test, range of motion and strength testing) lacked sufficient variability to conduct reliability analyses; however, a lack of variability between test days suggests consistency over a 1-year time frame. Our results provide evidence that specific physical measures are stable in monitoring functional ability over the course of a year.     

The effect of a low and high resource intervention on older drivers’ knowledge,behaviors and risky driving

This study aimed to compare an in-class Seniors on the MOVE (Mature Operators Vehicular Education) interactive multi-session driving curriculum with a self-guided MOVE curriculum for older adults. Using a two group randomized design, we sought to determine if there are between-group differences in older drivers’ knowledge and safety behaviors among participants. Forty-four participants with an average age of 79 years (SD = 7.1) were randomly assigned to the original MOVE program (SOM-A) or a lower resource (SOM-B) self-guided intervention. SOM-A is a four session program designed to improve older drivers safety knowledge and better understand skills for safer driving. SOM-B is a self-guided program with one required in-class session and one optional session. Subsequent to completion of both curricula, participants were offered CarFit, a comprehensive check of how well a senior driver and their vehicle work together. Baseline, post-intervention and 6-month follow up questionnaires were completed by participants. We found significant differences (p = .01) in the mean driving safety knowledge scores when comparing participants in SOM-A (3.7, SD 2.0) to those in SOM-B (0.87, SD 2.6). With regard to behavioral outcomes, we focused on always wearing a seatbelt, talking with a health care provider about driving ability, and sitting 10–12 inches from the steering wheel. The vast majority of participants reported always wearing their seat belts (SOM-A 100%, SOM-B 92%, p = 1.0), and very few reported talking with their doctors (SOM-A Baseline – 0%, Follow up 1 – 0%, p = n/a). Mean behavior change scores for participants sitting 10–12 inches from the steering wheel were significantly more likely among SOM-A (mean = .65, SD = .5) participants than those in SOM-B (mean = .29, SD = .5, p = .01) at first follow-up. Taken together, these findings suggest that the more intensive program is more effective and that driving safety programs focused on behaviors to self evaluate driving abilities continue to be needed to help older drivers remain safer on the road as they age. The involvement of health care providers in such efforts may be an untapped potential.     

Overly cautious and dangerous: An empirical evidence of the older driver stereotypes

Negative comments regarding the competency of older drivers are frequently heard in the general population. While negative stereotypes of older drivers seem to be present, their existence has yet to be empirically validated. We thus investigated the stereotypes pertaining to older drivers in two experiments. In both experiments young adults viewed 12 simulated clips of three categories of driving behaviors (i.e., younger adults’ unsafe behaviors, older drivers’ unsafe behaviors and appropriate-safe driving behaviors) without knowing the driver's age. They were asked to rate how representative the behaviors were of a typical younger, middle-aged, or older driver. Experiment 1 showed that older drivers’ unsafe behaviors were rated as significantly more representative of the typical older driver, while young adults’ unsafe behaviors were perceived as significantly more representative of the typical younger driver. In Experiment 2, younger participants viewed the same clips but were only asked to indicate whether the observed behavior was representative or not of the typical older driver. The main findings were replicated. When asked to describe the main features of the typical older drivers, participants qualified them as being overly cautious, uncomfortable behind the wheel, and unsafe and dangerous. The potential implications on driving performance of older drivers and on driving cessation and are discussed.     

Parenting adolescent drivers is both a continuation of parenting from earlier periods and an anticipation of a new challenge

Greater parental involvement in the driving process and greater parent-imposed limits on novice adolescent drivers hold promise for reducing driving fatalities. However, relatively little is known about why some parents are more involved in the driving process than others. Driving-specific parenting may be both a continuation of established patterns of parenting and a response to a novel developmental task. Adolescents (n = 242, M age 15.4 years, 49% male) who were enrolled in a drivers’ education courses and their parents (n = 276, 70% mothers) completed questionnaires reporting pre-driving parenting styles and monitoring behaviors; the adolescents’ previous driving experiences; perceptions of risks for novice adolescent drivers; attitudes regarding parental involvement; and expected levels of limit-setting and autonomy attainment once adolescents begins driving. Parents’ and adolescents’ involvement attitudes and expectations for limits on driving and autonomy attainment were linked in multivariate models with established patterns of parenting and perceptions of risk. The discussion emphasizes implications for prevention and intervention efforts to increase parental involvement and limits.     

Age-related declines in car following performance under simulated fog conditions

The present study examined age-related differences in car following performance when contrast of the driving scene was reduced by simulated fog. Older (mean age of 72.6) and younger (mean age of 21.1) drivers were presented with a car following scenario in a simulator in which a lead vehicle (LV) varied speed according to a sum of three sine wave functions. Drivers were shown an initial following distance of 18 m and were asked to maintain headway distance by controlling speed to match changes in LV speed. Five simulated fog conditions were examined ranging from a no fog condition (contrast of 0.55) to a high fog condition (contrast of 0.03). Average LV speed varied across trials (40, 60, or 80 km/h). The results indicated age-related declines in car following performance for both headway distance and RMS (root mean square) error in matching speed. The greatest decline occurred at moderate speeds under the highest fog density condition, with older drivers maintaining a headway distance that was 21% closer than younger drivers. At higher speeds older drivers maintained a greater headway distance than younger drivers. These results suggest that older drivers may be at greater risk for a collision under high fog density and moderate speeds.     

Experimental research on the effectiveness of speed reduction markings based on driving simulation: A case study

The objective of this paper is to test the effectiveness of speed reduction markings (SRMs). The empirical data including vehicle operations and drivers’ psychological and physical reactions were collected in a driving simulator. An index—the relative speed difference—was developed to evaluate the effectiveness of speed reduction markings. Researchers analyzed data to test the effectiveness of speed reduction markings and quantitatively study their effects and the deceleration process. Out of 15 subjects, there were 1 (7%), 2 (13%), and 7 (47%) subjects who decelerated while driving through the downhill section in the No SRMs scenario, Longitudinal SRMs scenario and Transverse SRMs scenario, respectively. In terms of speed and subjects’ decelerating maneuver, the results of the analysis of variance (ANOVA) and the contrast analysis (S–N–K method) showed that transverse speed reduction markings (TSRMs) could significantly influence subjects’ speed choice and maneuver (P < 0.05).     

The impact of Stereotype Threat on the simulated driving performance of older drivers

Older drivers are perceived as being dangerous and overly cautious by other drivers. We tested the hypothesis that this negative stereotype has a direct influence on the performance of older drivers. Based on the Stereotype Threat literature, we predicted that older driving performance would be altered after exposure to a Stereotype Threat. Sixty-one older drivers aged 65 and above completed a simulated driving assessment course. Prior to testing, half of the participants were told that the objective of the study was to investigate why older adults aged 65 and above were more implicated in on-road accidents (Stereotype Threat condition) and half were showed a neutral statement. Results confirmed that exposure to the threat significantly altered driving performance. Older adults in the Stereotype Threat condition made more driving mistakes than those in the control group. Interestingly, under a Stereotype Threat condition, older adults tended to commit more speeding infractions. We also observed that domain identification (whether driving is deemed important or not) moderated the impact of the threat. Taken together, these results support recent older drivers’ performance models suggesting that the interaction between individual and social factors need to be considered when examining older drivers’ performance.