Assessment of older drivers: relationships among on-road errors, medical conditions and test outcome

PROBLEM: It is essential that driver licensing authorities have a valid and reliable system for evaluating older drivers' continuing competency; road tests are usually required as part of such a system. This study sought to find information about the nature of driving errors made during license review tests, and about relationships between error type and test outcome for older drivers. METHOD: Data from licensing authority files from 533 road tests during a 12-month period were analyzed; medical and other referral information was included. Average driver age was 76 years. Performance scores were generated for intersection negotiation, lane changing, low speed manoeuvres, positioning and speed control, safety margin, and car control. RESULTS: Logistic regression analysis showed that test outcome was well predicted by a subset of driving performance scores; adding driver age to the model explained very little variance. Age alone was strongly associated with outcome. Relationships between referral information and test outcome are also reported. IMPACT: Results highlight several factors relevant to the development of more valid and reliable road tests for older drivers.     

The provisional license: nighttime and passenger restrictions--a literature review

PROBLEM: Due to inexperience and inadequate driving skills, the road is a very risky place for young and beginning drivers, yet such experience and skills can only be built by increased driving and exposure to risks on the road. Graduated driver licensing (GDL) allows beginning drivers to get their initial driving experience under less risky conditions and gradually eases them into more complex driving situations. This paper reviews the literature exploring two key features of the intermediate licensing phase of GDL, nighttime driving restrictions and passenger restrictions. METHOD: Literature review. RESULTS: Nighttime driving restrictions have been shown to effectively reduce the number and rate of crash involvements on the part of teenage drivers. Data suggest that having passengers in the car increases the likelihood of a fatal injury in young drivers and that this risk increases with the number of passengers. Young drivers were more likely to cause a crash when accompanied by their peers. DISCUSSION: Nighttime driving and passenger restrictions are effective in decreasing injuries among teenage drivers and their passengers, especially in the context of a full GDL system. Several research questions remain to be answered in order to fully refine and optimize the impact of these provisional measures.     

基于驾驶模拟的自动驾驶接管行为研究*

为探索有条件自动驾驶对非驾驶相关任务的允准边界,基于实车驾驶模拟器,设计自动驾驶接管试验典型场景,招募30名被试者开展驾驶模拟试验;要求驾驶人执行3种分心形式的驾驶次任务,系统发出接管请求提示后,驾驶人接管车辆控制权以避免险情发生,并分析驾驶人接管反应时间、驾驶负荷以及驾驶绩效等相关数据。结果表明:驾驶次任务涉及的分心形式越复杂,接管过程安全性越差,视觉分心任务与操作分心任务对接管行为影响显著;驾驶人更倾向于选择制动操作接管车辆,次任务分心程度越高,制动接管比例越大;与乘客聊天对接管行为影响不显著,看视频和玩手机游戏均会显著延长接管反应时间,增加工作负荷与车辆纵向减速度,玩手机游戏还会显著提升车辆横向加速度。     

冰雪道路环境对驾驶人视觉感知特性的影响

为预防冰雪道路环境中驾驶人因视觉感知错误引发交通事故,研究了冰雪道路环境对驾驶人视觉感知特性的影响,选择8名熟练驾驶人作为试验样本,且每2人一组,采用跟车调查的方法采集驾驶人对于自身感知车速和前导车车距的视觉感知信息,并利用非接触车速仪检测2辆跟驰行驶试验车的实际车速与车距,对冰雪条件与非冰雪条件下驾驶人的视觉感知信息进行分析对比。研究结果表明,在冰雪环境中驾驶人视觉感知车速比非冰雪环境中低5%～14%;但当2辆跟驰车辆前后车间距在50 m内时,驾驶人在冰雪环境与在非冰雪环境中行驶时,其视觉感知的车距无显著性差异。     

Developing and testing a hazard prediction task for novice drivers: A novel application of naturalistic driving videos

Introduction: Novice drivers’ inability to appropriately anticipate and respond to hazards has been implicated in their elevated crash risk. Our goal was to develop a driving hazard prediction task using naturalistic videos from the U.S. context that could distinguish between novice and experienced drivers. Method: Using the query builder from the SHRP 2 InSight Data Access Website, we identified a sample of 1034 videos for further review. Task criteria reduced these to 30 videos of near-crash events that were split into event and non-event segments and were used to develop the driving hazard prediction task (task). Participants, aged 16–20 years-old (22 novice and 19 experienced drivers) completed the task during which they watched event and non-event videos and were asked, “How likely was the driver of this car to get into a crash?” after each video. Overall ratings for hazardousness were calculated for experienced and novice drivers as well as a group difference score for hazardousness. Results: All participants rated event videos as more hazardous than non-event videos, but there was no main effect of group. Rather, there was a significant EventbyGroup interaction in which there were no group differences in hazard ratings for non-event videos, but experienced drivers rated event videos as more hazardous than novice drivers. Specific characteristics of the event videos, such as the hazard development period, were related to differences between novice and experienced drivers’ hazardousness ratings. Conclusion: To the best of our knowledge, this is the first use of naturalistic driving videos from an existing database as experimental stimuli. We found that the task discriminated between novice and experienced drivers’ ratings of hazardousness. This distinction suggests naturalistic driving videos may be viable stimuli for experimental studies. Practical Applications: The application of naturalistic driving video database for experimental research may hold promise.     

Aggressive behavior while driving as predictor of self-reported car crashes

PROBLEM: In Greece, there is a lack of scientific evidence on the relationship between aggressive behavior while driving and young drivers' involvement in car crashes; this study examined this potential relationship. METHODS: The randomly selected samples of 356 young drivers (18-24 years old) were interviewed through a questionnaire of self-reported car crash involvement, which mainly focused on their behavior on the road and the number of car crashes in which they had been involved. RESULTS: The statistical methods used were principal components analysis (PCA) and multiple regression analysis. Two factors relevant to aggressive driving emerged: (a) driving violations and (b) irritability while driving. The multivariate model suggested that driving just for fun (joyriding) and irritability were predictors of young drivers' involvement in car crashes. It was found that younger age was negatively associated with young drivers' involvement in car crashes. IMPACT ON GOVERNMENT AND INDUSTRY: The findings of this study can contribute in the formation of public policies aiming to prevent young drivers' car crashes. These findings can also be the starting point of some health promotion interventions trying to reduce car crashes and casualties on the road. Finally, the insurance companies may be interested in applying these findings into their field of interest.     

驾驶人视觉注意力需求与驾驶行为特性的关系

采用驾驶模拟系统平台,以不同车道类型及不同交通流状态(自由流/稳定流/不稳定流/强制流)为虚拟试验场,应用心理试验设计方法,测试得到21名被试在不同交通流状态下的视觉注意力需求及驾驶行为。对5种车道类型及4种交通流状态下被试驾驶时的视觉注意力需求特性和驾驶行为特性数据进行分析,得到不同车道不同交通流状态下的视觉注意力需求变化情况。利用多元回归方法分析了不同交通流状态下驾驶人视觉注意力需求与驾驶行为之间的关系,并构建了基于驾驶行为特性的驾驶人视觉注意力需求预测模型。结果表明,驾驶人视觉注意力需求与制动次数、油门踏板位移和车辆轨迹偏差之间存在相关关系。     

Driving context influences drivers' decision to engage in visual–manual phone tasks: Evidence from a naturalistic driving study

IntroductionVisual–manual (VM) phone tasks (i.e., texting, dialing, reading) are associated with an increased crash/near-crash risk. This study investigated how the driving context influences drivers' decisions to engage in VM phone tasks in naturalistic driving.MethodVideo-recordings of 1,432 car trips were viewed to identify VM phone tasks and passenger presence. Video, vehicle signals, and map data were used to classify driving context (i.e., curvature, other vehicles) before and during the VM phone tasks (N = 374). Vehicle signals (i.e., speed, yaw rate, forward radar) were available for all driving.ResultsVM phone tasks were more likely to be initiated while standing still, and less likely while driving at high speeds, or when a passenger was present. Lead vehicle presence did not influence how likely it was that a VM phone task was initiated, but the drivers adjusted their task timing to situations when the lead vehicle was increasing speed, resulting in increasing time headway. The drivers adjusted task timing until after making sharp turns and lane change maneuvers. In contrast to previous driving simulator studies, there was no evidence of drivers reducing speed as a consequence of VM phone task engagement.ConclusionsThe results show that experienced drivers use information about current and upcoming driving context to decide when to engage in VM phone tasks. However, drivers may fail to sufficiently increase safety margins to allow time to respond to possible unpredictable events (e.g., lead vehicle braking).Practical applicationsAdvanced driver assistance systems should facilitate and possibly boost drivers' self-regulating behavior. For instance, they might recognize when appropriate adaptive behavior is missing and advise or alert accordingly. The results from this study could also inspire training programs for novice drivers, or locally classify roads in terms of the risk associated with secondary task engagement while driving.     

Fatal crash between a car operating with automated control systems and a tractor-semitrailer truck

Abstract

Objective: The objective of this investigation was to evaluate the interaction between an SAE level 2 automated vehicle and the driver, including the limitations imposed by the vehicle on the driver.

Methods: A case study of the first fatal crash involving a vehicle operating with an automated control system was performed using scene evidence, vehicle damage, and recorded data available from the vehicle, and information from both drivers, including experience, phone records, computer systems, and medical information, was reviewed.

Results: System performance data downloaded from the car indicated that the driver was operating it using the Traffic-Aware Cruise Control and Autosteer lane-keeping systems, which are automated vehicle control systems within Tesla’s Autopilot suite. As the car crested the hill, a tractor trailer began its left turn onto a crossing roadway. Although reconstruction of the crash determined that there was sufficient sight distance for both drivers to see each other and take action, neither responded to the circumstances leading to the collision. Further, based on the speeds of the vehicles and simulations of the truck’s path, the car driver had at least 10.4?s to detect the truck and take evasive action. Neither the car driver nor the Autopilot system changed the vehicle’s velocity.

?At the time of the crash, the system performance data indicated that the last driver interaction with the system was 1?min 51?s prior when the cruise control speed was set to 74?mph. The driver was operating the vehicle using the Autopilot system for 37 of the 41?min in the last trip. During this period, the vehicle detected the driver’s hands on the steering wheel for a total of 25?s; each time his hands were detected on the wheel was preceded by a visual alert or auditory warning.

Conclusions: The National Transportation Safety Board (NTSB) determined that the probable cause of the Williston, Florida, crash was the truck driver’s failure to yield the right of way to the car, combined with the car driver’s inattention due to overreliance on vehicle automation, which resulted in the car driver’s lack of reaction to the presence of the truck. Contributing to the car driver’s overreliance on the vehicle automation was the car’s operational design, which permitted the driver’s prolonged disengagement from the driving task and his use of the automation in ways inconsistent with guidance and warnings from the manufacturer.     

A neglected risky behavior among children and adolescents: underage driving and injury in New South Wales,Australia

PROBLEM: Among different causes of injury, roads and traffic-related incidents contributed most to all child deaths. The majority of childhood and adolescent traffic-related deaths are young people killed as pedestrians or bicyclists. Underage driving is a particular risky behavior much neglected. This study aimed to describe some characteristics related to motor-vehicle crashes and crash-related injury in which the vehicle was driven by a young person who was under the legal age of obtaining a learner license in New South Wales, Australia. METHODS: Data used in this study were made available from the Roads and Traffic Authority of NSW for the period between 1996 and 2000. Crash information was collected and reported by NSW police at the scene of these motor-vehicle crash incidents. RESULTS: There were 526 crashes involving an underage driver recorded within the study period. The majority (79.5%) of these underage drivers were males with slightly more than half (58.0%) aged 15 years, and nearly 30% aged 14 years. Among these, 83.6% involved the driver of the vehicle being killed or injured. Among the injured or killed passengers, 128 (73.6%) were nonadult passengers under the age of 18 years. Seventy of these crashes occurred while the car was in pursuit by police. The adjusted relative risk of injury to at least one occupant in the vehicle should a crash occur for female underage drivers was two times (OR=2.01, 95% CI=1.27-3.20) as compared to male underage drivers. DISCUSSION: Underage driving poses a serious problem in terms of crash outcomes. Experimental driving and late-night outings for adolescents should be discouraged. Well-designed studies are required to further investigate the relationship between underage driving and on road risk-taking behavior among licensed adolescents. IMPACT ON INDUSTRY: Data obtained from this study indicate that adults, particularly parents, should discourage underage adolescents from experimenting driving and should actively cultivate a positive attitude toward driving.     

Child passengers and driver culpability in fatal crashes by driver gender

Objective: Studies based on accident statistics generally suggest that the presence of a passenger reduces adult drivers' accident risk. However, passengers have been reported to be a source of distraction in a remarkable portion of distraction-related crashes. Although the effect of passengers on driving performance has been studied extensively, few studies have focused on how a child passenger affects the driver.

?A child in a car is a potential distractor for parents, especially for mothers of small children, who often suffer from sleep deficit. The aim of this study was to examine how the presence of child passengers of different ages is associated with a higher driver culpability, which was expected due to child-related distraction and fatigue.

Methods: The analysis was based on the comprehensive data of fatal crashes studied in-depth by multidisciplinary road accident investigation teams in Finland during 1988–2012. Teams determine the primary party who had the most crucial effect on the origin of the event. We define the primary party as culpable and the others involved as nonculpable drivers. The culpability rate was defined as the percentage of culpable drivers and rates were compared for drivers with a child/teen passenger aged 0–17 years (N = 348), with an adult passenger without children (N = 324), and when driving alone (N = 579), grouped by child age and driver gender.

?Drivers with specific risk-related behavior (substantial speeding, driving when intoxicated, unbelted, or without a license) were excluded from the analyses, in order to make the drivers with and without children comparable. Only drivers 26–47 years old were included, representing parents with children 0–9 years of age.

Results: Male drivers were less often culpable with 0- to 17-year-old passengers in the car than alone or with adults. This was not the case with female drivers. The gender difference in culpability was most marked with small children age 0–4 years. Female drivers' culpability rate with a 0- to 4-year-old child passenger was higher and male drivers' culpability rate was lower compared to drivers without passengers or with only adult passengers.

Conclusion: The results indicate that female drivers are at higher risk of crashes than male drivers when driving with small children. Further research is needed to replicate this finding and to determine causal mechanisms.     

Deterioration of the useful visual field with ageing during simulated driving in traffic and its possible consequences for road safety

A previous study has shown that the useful visual field deteriorates in a simulated road traffic situation as a function of the driver’s age and of the vehicle’s speed under monotonous conditions [Rogé, J., Pébayle, T., Lambilliotte, E., Spitzenstetter, F., Giselbrecht, D., Muzet, A., 2004. Influence of age, speed and duration of monotonous driving task in traffic on the driver’s useful visual field. Vision Research 44 (23), 2737–2744]. The aim of this new experiment is to study the effects of traffic density and age on the useful visual field of the driver during a simulated driving task with controlled traffic characteristics (speed, number of cars) for all participants. In total, 10 young drivers (m = 28.2 years) and 10 older drivers (m = 51.2 years) followed a car in road traffic at an average speed of 126 km h⁻¹ during two 2 h sessions corresponding to two conditions of traffic (light traffic, with five vehicles around the participant; and heavy traffic, with nine vehicles). While following this vehicle, the driver had to detect changes in the colour of a signal located in the central part of his or her visual field and a signal that appeared at different eccentricities on the rear lights of other vehicles in the traffic. Analysis of the data indicated that age interacted with the location of the peripheral signal and density of traffic interacted with the duration of driving. The implications of these results are discussed in terms of road safety and in terms of models of deterioration of the useful visual field (general interference and tunnel vision).     

Assessing drivers' response during automated driver support system failures with non-driving tasks

IntroductionWith the increase in automated driver support systems, drivers are shifting from operating their vehicles to supervising their automation. As a result, it is important to understand how drivers interact with these automated systems and evaluate their effect on driver responses to safety critical events. This study aimed to identify how drivers responded when experiencing a safety critical event in automated vehicles while also engaged in non-driving tasks.MethodIn total 48 participants were included in this driving simulator study with two levels of automated driving: (a) driving with no automation and (b) driving with adaptive cruise control (ACC) and lane keeping (LK) systems engaged; and also two levels of a non-driving task (a) watching a movie or (b) no non-driving task. In addition to driving performance measures, non-driving task performance and the mean glance duration for the non-driving task were compared between the two levels of automated driving.ResultsDrivers using the automated systems responded worse than those manually driving in terms of reaction time, lane departure duration, and maximum steering wheel angle to an induced lane departure event. These results also found that non-driving tasks further impaired driver responses to a safety critical event in the automated system condition.ConclusionIn the automated driving condition, driver responses to the safety critical events were slower, especially when engaged in a non-driving task.Practical applicationTraditional driver performance variables may not necessarily effectively and accurately evaluate driver responses to events when supervising autonomous vehicle systems. Thus, it is important to develop and use appropriate variables to quantify drivers' performance under these conditions.     

Survival risk factors for fatal injured car and motorcycle drivers in single alcohol-related and alcohol-unrelated vehicle crashes

Introduction

A high percentage of drivers who die as a result of a single vehicle crash are under the influence of alcohol. We aimed to better understand the prevalence of these fatalities and the ratio of death to injuries based on various risk factors. We focused on alcohol-related and -unrelated single-vehicle crashes to investigate the influence of such risk factors on the time until death for car and motorcycle drivers.

Methods

We combined data from national police reports and a vital registration database in Taiwan. Survival analysis using Cox regression models was used to identify the risk factors of time until death.

Results

Overall, nearly 60% of car driver fatalities and 40% of motorcycle driver fatalities involved the consumption of alcohol. Survival analysis of single-vehicle crashes suggested that the traffic island separation between a car moving at a higher speed and motorcycle traffic resulted in a higher risk of death over time for motorcycle drivers who consumed alcohol. The factors attributed to a higher risk of death over time for motorcycle drivers were older age, crashing into trees, night-time driving, driving on curved roads, and driving on local roads. Driving without restraints and driving on roads with higher speed limits attributed to a higher risk of death over time for car drivers.

Conclusions

The factors that influence the risk of death over time in a motor-vehicle accident involving alcohol depended on different elements, which should each be considered when attempting to reduce this risk.

Impact on Industry

More efforts should be made to investigate the various risk factors in areas with large motorcycle populations.     

Drivers' visual behavior when using handheld and hands-free cell phones

ObjectiveThis study investigated driver distraction and how the use of handheld (HH), portable hands-free (PHF), and integrated hands-free (IHF) cell phones affected the visual behavior of motor vehicle drivers.MethodA naturalistic driving study recorded 204 participating drivers using video cameras and vehicle sensors for an average of 31 days. A total of 1564 cell phone calls made and 844 text messages sent while driving were sampled and underwent a video review. Baselines were established by recording epochs prior to the cell phone interactions. Total eyes-off-road time (TEORT) was examined to assess the visual demands of cell phone subtasks while driving. Percent TEORT was reported and compared against the baseline.ResultsVisual-manual subtasks performed on HH, PHF, and IHF cell phones were found to significantly increase drivers' mean percent TEORT. In contrast, conversing on an HH cell phone was found to significantly decrease drivers' mean percent TEORT, indicating that drivers looked at the forward roadway more often. No significant differences in percent TEORT were found for drivers conversing using PHF or IHF cell phones. The mean TEORT durations for visual-manual subtasks performed on an HH cell phone were significantly longer than the mean TEORT durations on either IHF or PHF cell phones.Practical applicationsThis research helps to further reinforce the distinction made between handheld and hands-free cell phone use in transportation distraction policy.     

Traffic climate and driver behaviors: The moderating role of driving skills in Turkey and China

Introduction: While road traffic accidents and fatalities are a worldwide problem, the rates of road traffic accidents and fatalities show differences among countries. Similarly, driver behaviors, traffic climate, and their relationships also show differences among countries. The aim of the current study is to investigate the moderating effect of driving skills on the relationship between traffic climate and driver behaviors by country. (Turkey and China). Method: There were 294 Turkish drivers and 292 Chinese drivers, and they completed the Traffic Climate Scale, the Driving Skills Inventory, and the Driver Behavior Questionnaire. The moderated moderation analyses were conducted with Hayes PROCESS tool on SPSS. Results: The results showed that safety skills moderated the relationship between internal requirements and violations both in Turkey and China. Safety skills also moderated the relationship between internal requirements and errors only in China and the relationship between functionality and violations in Turkey. Perceptual-motor skills moderated the relationships between external affective demands and errors, and also the relationship between internal requirements and positive driver behaviors in Turkey. It can be inferred that driving skills has different influences on traffic climate-driver behaviors relationship in different cultures and there might be cultural differences in the evaluation of drivers’ own driving skills. Practical Applications: Among driving skills, safety skills have a more critical role to increase road safety by decreasing number of violations. Interventions to increase safety skills of drivers might be promising for road safety.     

特长隧道环境下驾驶人注视转移特性研究

为了研究不同经验驾驶人在高速公路特长隧道环境下的注视转移特性,在高速公路特长隧道中开展实车实验,利用 iView X HED型眼动仪采集了32名不同经验驾驶人的眼动数据。运用动态聚类方法,对驾驶人注视区域进行划分,分析了职业与非职业驾驶员在高速公路隧道不同段与普通路段的注视转移规律与注意力分配特性。结果表明:相较于非职业驾驶人,职业驾驶员具有较强的注视前瞻性,且在隧道的不同段主要注视的区域因行车环境不同变化较小;驾驶人对同一目标需要重复注视才能提取足够的信息,且当行车环境复杂度增加或驾驶员驾驶经验不足时,重复注视概率增加;驾驶人在不同路段行车时,主要通过注视中间区域获取信息;行车环境与驾驶经验对驾驶人在中间近处、左侧区域及内后视镜区域的注视平稳分布存在显著的交互作用。     

Road characteristics and driver fatigue: a simulator study

Two experiments examined the influence of road characteristics on driver fatigue in a prolonged simulator drive. In experiment one, ten military truck drivers drove a mixed route, with straight, winding, and straight highway segments. In experiment two, 16 additional drivers drove either a straight, a winding, or a mixed route. Fatigue symptoms were assessed using performance, subjective, and psychophysiological measures (HRV). We hypothesized that drivers adopt different fatigue-coping strategies relative to the demands of the drive. Thus, on straight roads drivers are more likely to loosen their driving demands by either increasing their driving speed and/or not maintaining the lane position, as the road is tolerant to both strategies, whereas on winding roads, drivers are more likely to increase their speed but not their lane positioning. Our results confirm that decremental changes in driving performance varied among road types. In the straight road components, we found decrements in the quality of lane maintaining (experiment one) and steering quality (experiments one and two) and longitudinal speed (experiment two). In the winding road, we found that drivers increased their driving speed over time (experiments one and two).     

Analysis of effects of driver’s evasive action time on rear-end collision risk using a driving simulator

Introduction: Driver’s evasive action is closely associated with collision risk in a critical traffic event. To quantify collision risk, surrogate safety measures (SSMs) have been estimated using vehicle trajectories. However, vehicle trajectories cannot clearly capture presence and time of driver’s evasive action. Thus, this study determines the driver’s evasive action based on his/her use of accelerator and brake pedals, and analyzes the effects of the driver’s evasive action time (i.e., duration of evasive action) on rear-end collision risk. Method: Fifty drivers’ car-following behavior on a freeway was observed using a driving simulator. An SSM called “Deceleration Rate to Avoid Crash (DRAC)” and the evasive action time were determined for each driver using the data from the driving simulator. Each driver tested two traffic scenarios – Cars and Trucks scenarios where conflicting vehicles were cars and trucks, respectively. The factors related to DRAC were identified and their effects on DRAC were analyzed using the Generalized Linear Models and random effects models. Results: DRAC decreased with the evasive action time and DRAC was closely related to drivers’ gender and driving experience at the road sections where evasive action to avoid collision was required. DRAC was also significantly different between Cars and Trucks scenarios. The effect of the evasive action time on DRAC varied among different drivers, particularly in the Trucks scenario. Conclusions: Longer evasive action time can significantly reduce crash risk. Driver characteristics are more closely related to effective evasive action in complex driving conditions. Practical Applications: Based on the findings of this study, driver warning information can be developed to alert drivers to take specific evasive action that reduces collision risk in a critical traffic event. The information is likely to reduce the variability of the driver’s evasive action and the speed variations among different drivers.     

Assessing driver behavior using shrp2 adverse weather data

IntroductionThis study explored how drivers adapt to inclement weather in terms of driving speed, situational awareness, and visibility as road surface conditions change from dry to slippery and visibility decreases. The proposed work mined existing data from the SHRP 2 NDS for drivers who were involved in weather-related crash and near-crash events. Baseline events were also mined to create related metadata necessary for behavioral comparisons. Methods: Researchers attempted, to the greatest extent possible, to match non-adverse-weather driving scenarios that are similar to the crash and near-crash event for each driver. The ideal match scenario would be at a day prior to the crash during non-adverse weather conditions having the same driver, at the same time of day, with the same traffic level on the same road on which the crash or near-crash occurred. Once the matched scenarios have been identified, a detailed analysis will be performed to determine how a driver’s behavior changed from normal driving to inclement-weather driving. Results: Data collected indicated that, irrespective of site location (i.e., state), most crashes and near-crashes occurred in rain, with only about 12% occurring in snowy conditions. Also, the number of near-crashes was almost double the number of crashes showing that many drivers were able to avoid a crash by executing an evasive maneuver such as braking or steering. Conclusions: Most types of near crashes were rear-end and sideswipe avoidance epochs, as the drivers may have had a difficult time merging or trying to change lanes due to low visibility or traffic. Hard braking combined with swerving were the most commonly used evasive maneuvers, occurring when drivers did not adjust their speeds accordingly for specific situations. Practical applications: Results from this study are expected to be utilized to educate and guide drivers toward more confident and strategic driving behavior in adverse weather.