Examining teen driver crashes and the prevalence of distraction: Recent trends, 2007-2015

Identifying the causal effects of driver distraction on hazardous actions at intersections based on propensity score weighting

Distracted driving is a threat to traffic safety that can result in more traffic crashes. Although previous studies have been conducted to explore the relationship between driver distraction and hazardous driving actions, few studies are available to identify the causation between them. Thus, the study intended to evaluate the causal effects of distraction on hazardous driving actions at intersections based on the crash data extracted from the Crash Report Sampling System (2021-2022). The multinomial logit model was employed to reveal the factors contributing to driver distraction. Then, propensity score weighting was adopted to balance the factor distributions between distraction and non-distraction cases to identify the causal effects on hazardous actions. Results indicated that 1) the propensity of distraction is relevant to factors such as the driver's age, gender, vehicle type, speed limit, area, weather, and light condition, 2) driver distraction can significantly increase the probability of risky actions including speeding, running red lights, failing to obey stop signs, failing to yield, following too closely, and 3) the causal effects show great diversity for different distraction types. The findings serve to understand the influence mechanism of distraction on specific crash risks and develop countermeasures to reduce distraction and hazardous driving actions.

How do drivers mitigate the effects of naturalistic visual complexity? : On attentional strategies and their implications under a change blindness protocol

How do the limits of high-level visual processing affect human performance in naturalistic, dynamic settings of (multimodal) interaction where observers can draw on experience to strategically adapt attention to familiar forms of complexity? In this backdrop, we investigate change detection in a driving context to study attentional allocation aimed at overcoming environmental complexity and temporal load. Results indicate that visuospatial complexity substantially increases change blindness but also that participants effectively respond to this load by increasing their focus on safety-relevant events, by adjusting their driving, and by avoiding non-productive forms of attentional elaboration, thereby also controlling "looked-but-failed-to-see" errors. Furthermore, analyses of gaze patterns reveal that drivers occasionally, but effectively, limit attentional monitoring and lingering for irrelevant changes. Overall, the experimental outcomes reveal how drivers exhibit effective attentional compensation in highly complex situations. Our findings uncover implications for driving education and development of driving skill-testing methods, as well as for human-factors guided development of AI-based driving assistance systems.

Effects of levels of automation and non-driving related tasks on driver performance and workload: A review of literature and meta-analysis

This study assessed the effects of different levels of automation and non-driving related tasks (NDRT) on driver performance and workload. A systematic literature review was conducted in March 2021 using Compendex, Google Scholar, Web of Science, and Scopus databases. Forty-five studies met the inclusion criteria. A meta-analysis was conducted and Cochrane risk of bias tool and Cochran's Q test were used to assess risk of bias and homogeneity of the effect sizes respectively. Results suggested that drivers exhibited safer performance when dealing with critical incidents in manual driving than partially automated driving (PAD) and highly automated driving (HAD) conditions. However, drivers reported higher workload in the manual driving mode as compared to the HAD and PAD conditions. Haptic, auditory, and visual-auditory takeover request modalities are preferred over the visual-only modality to improve takeover time. Use of handheld NDRTs significantly degraded driver performance as compared to NDRTs performed on mounted devices.

Determining the risk of driver-at-fault events associated with common distraction types using naturalistic driving data

INTRODUCTION

Studies thus far have focused on automobile accidents that involve driver distraction. However, it is hard to discern whether distraction played a role if fault designation is missing because an accident could be caused by an unexpected external event over which the driver has no control. This study seeks to determine the effect of distraction in driver-at-fault events.

METHOD

Two generalized linear mixed models, one with at-fault safety critical events (SCE) and the other with all-cause SCEs as the outcomes, were developed to compare the odds associated with common distraction types using data from the SHRP2 naturalistic driving study.

RESULTS

Adjusting for environment and driver variation, 6 of 10 common distraction types significantly increased the risk of at-fault SCEs by 20-1330%. The three most hazardous sources of distraction were handling in-cabin objects (OR = 14.3), mobile device use (OR = 2.4), and external distraction (OR = 1.8). Mobile device use and external distraction were also among the most commonly occurring distraction types (10.1% and 11.0%, respectively).

CONCLUSIONS

Focusing on at-fault events improves our understanding of the role of distraction in potentially avoidable automobile accidents. The in-cabin distraction that requires eye-hand coordination presents the most danger to drivers' ability in maintaining fault-free, safe driving. Practical Applications: The high risk of at-fault SCEs associated with in-cabin distraction should motivate the smart design of the interior and in-vehicle information system that requires less visual attention and manual effort.

Analysis of Drivers’ Eye Movements on Roundabouts: A Driving Simulator Study

Roundabouts are considered as one of the most efficient forms of intersection that substantially reduce the types of crashes that result in injury or loss of life. Nevertheless, they do not eliminate collision risks, especially when human error plays such a large role in traffic crashes. In this study, we used a driving simulator and an eye tracker to investigate drivers’ eye movements under cell phone-induced distraction. A total of 45 drivers participated in two experiments conducted under distracted and non-distracted conditions. The results indicated that, under distracting conditions, the drivers’ fixation duration decreased significantly on roundabouts, and pupil size increased significantly.

The role of off-path glances: A quantitative analysis of rear-end conflicts involving Chinese professional truck drivers as the striking partners

INTRODUCTION

Rear-end crashes are one of the most frequent crash types in China, leading to significant economic and societal losses. The development of active safety systems - such as Automatic Emergency Braking System (AEBS) - could avoid or mitigate the consequences of these crashes in Chinese traffic situations. However, a clear understanding of the crash causation mechanisms is necessary for the design of these systems.

METHOD

Manually coded variables were extracted from a naturalistic driving study conducted with commercial vehicles in Shanghai. Quantitative analyses of rear-end crashes and near crashes (CNC) were conducted to assess the prevalence, duration, and location of drivers' off-path glances, the influence of lead vehicle brake lights on drivers' last off-path glance, and driver brake onset, and the influence of off-path glances and kinematic criticality on drivers' response to conflicts.

RESULTS

The results indicate that the Chinese truck drivers in our study rarely engage in distracting activities involving a phone or other handheld objects while driving. Instead, they direct their off-path glances mainly toward the mirrors, and the duration of off-path glances leading to critical situations are shorter compared to earlier analyses performed in Western countries. The drivers also often keep small margins.

CONCLUSIONS

Overall, the combination of short time headway with off-path glances directed toward the mirror originates visual mismatches which, associated to a rapid change in the kinematic situation, cause the occurrence of rear-end CNC. When drivers look back toward the road after an off-path glance, a fast response seems to be triggered by lower values of looming compared to previous studies, possibly because of the short time headways. Practical Application: The results have practical implications for the development of driver models, for the design of active safety systems and automated driving, and for the design of campaigns promoting safe driving.

Driver distraction and inattention in fatal and injury crashes: Findings from in-depth road crash data

Objective: This study investigated the contribution of driver distraction and inattention within fatal and injury crashes using recent in-depth road crash investigation data. To assist in developing system-based solutions, this study also examined the wider context in which inattention-related crashes occurred and the characteristics of inattentive drivers. Methods: The sample included in-depth crash data from 186 fatal and injury crashes in South Australia investigated from 2014 to 2018. Crash case notes were reviewed to determine whether there was evidence that attentional failures contributed to the crash. Using an adapted taxonomy of inattention, 5 subtypes of driver inattention were defined: Misprioritized attention, neglected attention, cursory attention, diverted attention (distraction), and unspecified inattention. The characteristics of inattention crashes were also compared with those for non-inattention-related crashes. Results: Of the 160 crashes for which there was sufficient information to determine whether inattention was a factor, 31.3% showed evidence of driver inattention contributing to the crash. The most common subtypes of inattention were distraction (13.8% of all crashes) and driver misprioritized attention (8.1%). The distraction-related crashes included a variety of different distractions, the majority of which were not technology based (e.g., passenger interaction, searching for/adjusting objects, emotional stress, other road users), with those located in-vehicle the most prevalent. Distraction from mobile phone use was identified in 2.5% of all crashes. The majority of distractions were cognitive (64%) and voluntary (77%) in nature. Inattention crashes were most likely to involve right turn/angle or rear-end crash types and occur at intersections, in metropolitan areas, and in lower speed zones. Conclusions: The findings established that almost a third of fatal and injury crashes involved driver inattention and distraction and many of these could have been prevented. System-wide solutions that could mitigate or prevent distraction crashes include intervening vehicle safety technologies, infrastructure solutions to promote a forgiving road environment, blocking capabilities within technologies to prevent communications while driving, and interventions communicating the risks associated with inattention. Of significance, this study also demonstrated the importance of in-depth data for understanding the contribution of distraction and inattention errors in crash causation.

Exploring the impact of "soft blocking" on smartphone usage of young drivers

Smartphone usage while driving, and particularly texting, are well recognized as a major road safety concern. This paper presents an attempt to evaluate the effect of countermeasures aimed at mitigating this usage. These countermeasures, which are automatically activated, may be considered "soft blockers": silencing and hiding notifications, as well as sending an automatic reply to the person trying to contact the driver. A naturalistic study was conducted with 167 young Israeli drivers, who installed a research-oriented smartphone app, which continuously monitored their smartphones usage while driving and, in addition, activated "soft blocking" in the study's intervention stage. The evaluation is based on measures which capture the number of times drivers "touch" their smartphone screens, and on the vehicle's speed when these screen-touches occur. The results, based on 6633 hours of driving logged on 23,019 trips, indicate that a reduction of approximately 20% was obtained in the average number of screen-touches during the intervention stage of the study; that is, in the experimental groups but also in the control group, which was merely monitored. In addition, when young drivers touched the screen, the vehicle was more likely not in motion. The current paper highlights the potential of "soft blockers", as well as the awareness of being monitored, for mitigating smartphone usage while driving.