Sixteen-year-old drivers in fatal crashes, United States, 2003

OBJECTIVE: Key features of graduated licensing were introduced in 46 states and the District of Columbia between 1993 and 2003. State evaluations consistently have reported positive overall effects and positive effects of nighttime and passenger restrictions. Sixteen year-olds are the main target of graduated licensing, and the present study investigated changes in their fatal crash involvement and crash characteristics that have taken place nationally during 1993-2003. By looking at 16 year-olds nationally, the study does not constitute a direct test of the effect of graduated licensing laws per se. METHODS: Data on fatal crashes were obtained from the Fatality Analysis Reporting System. Sixteen year-olds were compared with older drivers. RESULTS: During these years, the extent to which 16-year-old drivers were in fatal crashes decreased substantially compared with older age groups. The drop in the per capita crash rate for 16 year-olds was 26%. The major change was a reduction in crashes involving transporting young passengers, especially in jurisdictions with restrictions that target these crashes. There was no change in the proportion of fatal late-night crashes even in states restricting this activity. CONCLUSIONS: There has been some progress nationally in reducing the crash problem for 16 year-olds, but this still is a big problem. To achieve further progress, the gaps and weaknesses in present graduated licensing laws will need to be addressed.     

Aggressive driving behaviour in young drivers (aged 16 through 25) involved in fatal crashes

IntroductionWe wished to determine the extent to which number of passengers, driver age, and sex were associated with aggressive driving actions (ADAs) in young drivers involved in a fatal crash.MethodsWe used U.S. fatal-crash data from Fatality Analysis Reporting System (FARS), 1991 –2008. Proxy measures of aggressive driving included ADA presence and speed differential (posted speed limit minus estimated travel speed). We examined the odds of an ADA and speed differential in young drivers (aged 16 to 25) by passenger status.ResultsCompared to driving alone young drivers (aged 16) had increased odds of an ADA between 14% (OR: 1.14; 95% CI: 1.07; 1.22) and 95% (OR: 1.95; 95% CI: 1.40; 2.74) when accompanied by one and five passengers, respectively. Further, carrying a higher number of passengers was a stronger predictor of speeding in younger drivers.ConclusionsThis study supports the use of graduated licensing approaches. Specifically, developing interventions to reduce aggressive driving appear imperative.Impact on IndustryWhile the results of our study support the use of graduated licensing approaches there is room for improvement. Our study indicates that tackling impaired driving is not sufficient to drastically reduce aggressive driving among the youngest drivers. Further research on young drivers is required to understand the influence of peers and the role of gender on driving behavior. Strategies to reduce aggressive driving behaviors among the youngest drivers may not only prevent crashes during their early driving careers but may also translate into a reduced crash risk over their lifetime.     

Antecedents of fatigue, close calls, and crashes among commercial motor-vehicle drivers

PROBLEM: Minimizing driver fatigue among commercial motor-vehicle (CMV) drivers is a major safety issue in the United States. This study examines the effects of potentially fatigue-inducing factors inherent in truck driving work and company safety management in explaining: (a) drivers driving while fatigued, (b) the frequency of close calls due to fatigue, and (c) actual crashes among CMV drivers. METHOD: Data for this study are derived from a survey of CMV drivers in 116 trucking firms, with all data being driver-reported. The relative roles of fatigue-inducing factors and safety management practices in explaining variation in fatigue, close calls, and crashes are reported, along with the roles of fatigue in affecting close calls and crashes via hierarchical regression. RESULTS: Findings indicated that fatigue-inducing factors inherent in driving work and safety practices accounted for appreciable variation in driving fatigued (R(2) =.42) and close calls (R(2) =.35), but not crash involvement. Driving while fatigued also accounted for incremental increases in the amount of variation in close calls, after consideration of inherent factors and safety practices. IMPACT ON INDUSTRY: Findings indicate that safety practices (e.g., establishment of a strong safety culture, dispatcher scheduling practices, company assistance with fatiguing behaviors such as loading and unloading) have considerable potential to offset fatigue-inducing factors associated with truck driving work.     

Prediction of responsibility for drivers and riders involved in injury road crashes

Introduction: Responsibility analysis allows the evaluation of crash risk factors from crash data only, but requires a reliable responsibility assessment. The aim of the present study is to predict expert responsibility attribution (considered as a gold-standard) from explanatory variables available in crash data routinely recorded by the police, according to a data-driven process with explicit rules. Method: Driver responsibility was assessed by experts using all information contained in police reports for a sample of about 5000 injury crashes that occurred in France in 2011. Three statistical methods were used to predict expert responsibility attribution: logistic regression with L1 penalty, random forests, and boosting. Potential predictors of expert attribution referred to inappropriate driver actions and to external conditions at the time of the crash. Logistic regression was chosen to construct a score to assess responsibility for drivers and riders in crashes involving one or more motor vehicles, or involving a cyclist or pedestrian. Results: Cross-validation showed that our tool can predict expert responsibility assessments on new data sets. In addition, responsibility analyses performed using either the expert responsibility or our predicted responsibility return similar odds ratios. Our scoring process can then be used to reliably assess responsibility based on national police report databases, provided that they include the information needed to construct the score.     

Trends and patterns in fatal US motorcycle crashes, 2000–2016

Objective: To investigate trends of motorcyclist fatalities and identify at-risk populations by motorcyclist demographics and crash characteristics.

Methods: We used the Fatality Analysis Reporting System (FARS) database (2000–2016) to track fatality rate trends, which were quantified by using Poisson mixed-effects regression models comparing 2000–2001 and 2007–2008, as well as 2009–2010 and 2015–2016.

Results: The overall fatality rate per 100,000 population increased from 2000 to 2016, defined by two trend lines—before and after the economic recession in 2008–2009. The overall fatality rate ratio between 2000–2001 and 2007–2008 was 1.60 [95% Confidence Interval (CI): 1.51–1.70], and between 2009–2010 and 2015–2016 was 1.09 (95% CI: 1.02–1.18). Fatality rates increased among all age groups, particularly for motorcyclists aged 60 and older. Those aged 18–29 had the highest fatality rates overall. Age-and-sex standardized state fatality rates were consistently highest in Wyoming, South Dakota, and South Carolina and lowest in Massachusetts, New York and New Jersey.

Conclusion: Motorcycle fatality rates increased overall and across all age groups between 2000 and 2016. Fatalities for the oldest riders showed the steadiest increasing trends. Results highlight the continued public health burden of motorcyclist fatalities and, by extension, the importance of improving motorcycle safety.     

The Iowa Graduated Driver Licensing program: effectiveness in reducing crashes of teenage drivers

PROBLEM: Graduated Driver Licensing (GDL) programs vary in the United States in terms of implementation and restrictions. The State of Iowa's GDL program is assessed for its effectiveness in reducing crashes among teenage drivers. METHOD: Time series analysis was used to evaluate police documented crashes involving 16-, 17-, and 18-year-old drivers over a 10 year period, with an intervention identified at the point of GDL implementation. RESULTS: After controlling for seasonal trends and auto-correlative effects, a significant reduction in the crash rate of and 16- and 17-year-old drivers was observed due to the GDL implementation. However, there were no significant reductions in crash rates for 18-year-old drivers. DISCUSSION: The analyses suggest that the Iowa GDL program is effective in reducing the crash rates of 16- and 17-year-old drivers but the effects do not sustain for 18-year-old drivers. IMPACT ON INDUSTRY: The results suggest that the program appears to be working, however further analysis is needed to determine what factors are preventing lasting effects for these teenage drivers.     

Medical review process and license disposition of drivers referred by law enforcement in Virginia

IntroductionMedically at-risk drivers come to the attention of licensing authorities through referrals from a variety of sources, including: physicians, family members, court systems, and law enforcement. A recently sponsored project by the National Highway Traffic Safety Administration examined a training intervention for law enforcement to increase their awareness of medical conditions and medications that impair driving and the procedures for reporting these drivers in Virginia.MethodA component of this project included an evaluation of the medical review process and licensing outcomes for 100 drivers randomly selected from a pool of over 1,000 drivers referred from law enforcement officers to the Virginia Department of Motor Vehicles over a 6-month period in 2007 and 2008 prior to any training program intervention.ResultsKey findings from the evaluation of 100 drivers referred for medical review by law enforcement were as follows. Over two-thirds of the drivers came to the attention of the referring officer because they were involved in a crash. The most prevalent indications of a medical condition or functional impairment provided by law enforcement for these referrals were: loss of consciousness, blackout, or seizures (28%); disorientation, confusion, and mental disability (16%); and physical impairments (8%). Eighty-eight percent of the drivers received some type of licensing action (e.g., restriction, suspension, or periodic review). Only 12% of the referred drivers did not require any licensing action.ConclusionsLaw enforcement provides a vital role in the identification and referral of medically impaired drivers to licensing authorities for reexamination. Training programs can inform law enforcement officers of the signs of medical impairment (both on-road behavior, and physical and psychological clues once a driver has been pulled over), and procedures for reporting their observations and concern for safety to licensing authorities.Impact on IndustryReexamination of drivers with functional and medical impairments and any consequent restrictions and/or periodic reporting requirements can improve the safety and mobility of these drivers, and the motoring public as well.     

Prediction of cervical spine injury risk for the 6-year-old child in frontal crashes

This article presents a series of 49 km/h sled tests using the Hybrid III 6-year-old dummy in a high-back booster, a low-back booster, and a three-point belt. Although a 10-year review at a level I trauma center showed that noncontact cervical spine injuries are rare in correctly restrained booster-age children, dummy neck loads exceeded published injury thresholds in all tests. The dummy underwent extreme neck flexion during the test, causing full-face contact with the dummy's chest. These dummy kinematics were compared to the kinematics of a 12-year-old cadaver tested in a similar impact environment. The cadaver test showed neck flexion, but also significant thoracic spinal flexion which was nonexistent in the dummy. This comparison was expanded using MADYMO simulations in which the thoracic spinal stiffness of the dummy model was decreased to give a more biofidelic kinematic response. We conclude that the stiff thoracic spine of the dummy results in high neck forces and moments that are not representative of the true injury potential.     

The impact of 2-day jail sentences for drunk drivers in Hennepin County,Minnesota

In 1982, the judges of the Hennepin County Municipal Court met and collectively decided that they would start sentencing all convicted first-time alcohol-related offenders to serve 2 days in jail. A research study was initiated to evaluate the effects of such sentences. It was the purpose of the evaluation to examine not only the effect of this policy on traffic safety, but also its impact on the operation of the court, the correctional system, driving while intoxicated (DWI) enforcement activity, and public perceptions. The major findings were: (a) in spite of the fact that 2-day jail sentences were voluntarily imposed by the municipal judges (vs. statutorily required), there was a high degree of judicial compliance; (b) the Hennepin County Adult Corrections Facility for the most part was able to effectively accommodate the DWI offenders serving 2-day sentences; and (c) there was a statistically significant average monthly reduction in Hennepin County of 35 nighttime injury accidents coincident with the adoption of the policy and after a 2-month lag time. This is a 20% reduction when compared to the prepolicy monthly average. There has also been a marked increase in the number of DWI arrests. Overall, the experience in Hennepin County has been positive and may have important implications for other jurisdictions considering changes in their DWI policies.     

Ankle fracture patterns in drivers are associated with femoral fracture,higher BMI,and advanced age

Objective: Despite advances in vehicle safety systems, motor vehicle crashes continue to cause ankle fractures. This study attempts to provide insight into the mechanisms of injury and to identify the at-risk population groups.

Methods: A study was made of ankle fractures patients treated at an urban level 1 trauma center following motor vehicle crashes, with a concurrent analysis of a nationally representative crash data set. The national data set focused on ankle fractures in drivers involved in frontal crashes. Statistical analysis was applied to the national data set to identify factors associated with fracture risk.

Results: Malleolar fractures occurred most frequently in the driver's right foot due to pedal interaction. The majority of complex/open fractures occurred in the left foot due to interaction with the vehicle floor. These fractures occurred in association with a femoral fracture, but their broad injury pattern suggests a range of fracture causation mechanisms. The statistical analysis indicated that the risk of fracture increased with increasing driver body mass index (BMI) and age.

Conclusions: Efforts to reduce the risk of driver ankle injury should focus on right foot and pedal interaction. The range of injury patterns identified here suggest that efforts to minimize driver ankle fracture risk will likely need to consider injury tolerances for flexion, pronation/supination, and axial loading in order to capture the full range of injury mechanisms. In the clinical environment, physicians examining drivers after a frontal crash should consider those who are older or obese or who have severe femoral injury without concurrent head injury as highly suspicious for an ankle injury.     

The influence of the age and sex distributions of drivers on the reduction of impaired crashes: Ontario, 1974-1999

Legislative changes and public media campaigns to prevent impaired driving are often cited as explanations for the reduction in the rate of impaired crashes over the past 25 years in most of the industrialized world. Other factors may have contributed to these reductions, such as changes in the age and sex distribution of the driver population. The primary purpose of this article is to assess the extent to which the reduction in impaired crashes in Ontario, Canada, may be attributable to the changing age and sex distribution of drivers. In Ontario, the rate of impaired crashes declined by 78.1% from 1974 to 1999. During this time period, the average age of drivers increased from 39.4 years in 1974 to 43.2 in 1999. Similarly, from 1974 to 1999 the percentage of all drivers that were women increased from 39.6% to 46.8%. Since statistics show the likelihood of impaired crashes is lower for both older drivers and women, the reduction of impaired crashes is partially due to these demographic changes. Using indirect standardization, the aging population accounted for an 8.6% decline in the rate of impaired crashes. The changing sex distribution of drivers accounted for a 9.4% decline in impaired crashes. Other global factors may also help to explain the reduction of impaired crashes, such as general road safety improvements and reductions in per adult consumption of alcohol.     

Car safety and social differences in traffic injuries among young adult drivers: a study of two-car injury-generating crashes in Sweden

Objective—The study examines whether socioeconomic and sex differences in road-traffic crashes leading to injury vary according to car-safety level.Method—Individuals records of subjects born 1970–1972 registered in the Swedish Census of 1985 (n = 334,070) are linked to road-traffic-crash data for the period 1988–2000 for first police-registered two-car crashes leading to severe or fatal injury (n = 4875). Injuries are split into categories according to level of car safety on a five-point scale, based on criteria related to crash safety. Account is taken of both how the car is constructed and the effectiveness of its safety equipment (such as airbags and seat belts). For each car-safety level, relative risks are computed considering socioeconomic groups of origin, educational level, and sex.Results—No substantial differences between drivers in different socioeconomic positions of origin is observed except for crashes involving cars 30% better than average with regard to safety. There are consistent risk differences across all car-safety categories according to educational level. Male drivers show an elevated risk of injury in all car categories, except for cars with the poorest safety where they are at significant under-risk.Conclusions—Car-safety level impacts on social differences in road-traffic injury risks in specific and restricted manners. Car-safety development is an important factor in improved road safety, but it may not benefit all to the same extent.     

Child passenger injury risk in motor vehicle crashes: a comparison of nighttime and daytime driving by teenage and adult drivers

INTRODUCTION: To examine the association between child passenger injury risk, restraint use, and crash time (day vs. night) for children in crashes of vehicles driven by teenage versus adult drivers. METHODS: Cross-sectional study involving telephone interviews with insured drivers in a probability sample of 6,184 crashes involving 10,028 children. RESULTS: Child passengers in teen nighttime crashes had an increased injury risk and an increased risk of restraint nonuse compared with those in teen daytime crashes. This increased injury risk can be explained by differences in the age of child passengers, collision type, and child passenger's restraint status associated with time of day. CONCLUSIONS: In order to limit the risk of injury to child passengers driven by teens, Graduated Driver Licensing (GDL) laws should include provisions restricting nighttime driving, as well as mandates for age-appropriate restraint for child passengers. Consideration should also be given for education in child passenger safety for novice teen drivers as part of the licensing process. IMPACT ON INDUSTRY: Results of this study can be used to support advocacy efforts by the automotive industry and others to promote nighttime driving restrictions on novice drivers. In addition, given that both driver groups were more likely to be involved in a single-vehicle collision during the night, technologies such as electronic stability control may offer opportunities for protection. Further reseach on specific circumstances of teen nighttime crashes is needed to inform industry efforts to improve visibility or vehicle operation under poor lighting conditions.     

Associations of repeated high alcohol use with unsafe driving behaviors,traffic offenses,and traffic crashes among young drivers: Findings from the New Zealand Drivers Study

Objective: The objective of this study was to describe self-reported high alcohol use at each of the 3 licensing stages of graduated driver licensing and its relationship to drink-driving behaviors, intentional risky driving, aggressive driving, alcohol traffic offenses, non-alcohol traffic offenses, and traffic crashes.

Methods: The New Zealand Drivers Study (NZDS) is a multistage, prospective cohort study of newly licensed drivers interviewed at all 3 stages of the graduated driver licensing system: learner (baseline), restricted (intermediate), and full license. At each stage, alcohol use was self-reported using the Alcohol Use Disorders Identification Test (AUDIT-C), with high alcohol use defined as a score of ≥4 for males and ≥3 for females. Sociodemographic and personality data were obtained at the baseline interview. Alcohol-related, intentional risky, and aggressive driving behaviors were self-reported following each license stage. Traffic crashes and offenses were identified from police records. Crashes were also self-reported.

Results: Twenty-six percent (n = 397) reported no high alcohol use, 22% at one license stage, 30% at 2 stages, and 22% at 3 stages. Poisson regression results (unadjusted and adjusted) showed that the number of stages where high alcohol use was reported was significantly associated with each of the outcomes. For most outcomes, and especially the alcohol-involved outcomes, the relative risk increased with the number of stages of high alcohol use.

Conclusions: We found that high alcohol use was common among young newly licensed drivers and those who repeatedly reported high alcohol use were at a significantly higher risk of unsafe driving behaviors. Recently introduced zero blood alcohol concentration (BAC) should help to address this problem, but other strategies are required to target persistent offenders.     

Severity of motorcycle crashes in Dar es Salaam,Tanzania

Objective: Motorcycles are a common mode of transportation in low- and middle-income countries. Tanzania, in particular, has experienced an increased use of motorcycles in the last decade. In Dar es Salaam, motorcycles provide door-to-door travel and often operate where more conventional services are uneconomical or physically impossible to maneuver. Although motorcycles play a crucial role in improving mobility in the city, they have several safety issues. This study focuses on identifying factors influencing the severity of motorcycle crashes.

Method: A multinomial logit analysis was conducted to identify factors influencing the severity of motorcycle crashes in Dar es Salaam, Tanzania. The severity categories were fatal, severe injury, minor injury, and property damage only (PDO). The analysis was based on a total of 784 motorcycle crashes that occurred from 2013 to 2016.

Results: The following factors were found to increase the probability of a fatality: Speeding, driving under the influence, head-on impact, presence of horizontal curves, reckless riding, off-peak hours, violations, and riding without a helmet. The results indicate that crashes occurring on weekdays, during peak hours, at intersections, involving a rear-end impact, in daylight, on street roads, and under clear weather conditions decrease the probability of a fatality. However, minor injury and PDO crashes were found to be associated with crashes occurring during peak hours, at intersections, and on street roads, as well as failure to yield right-of-way.

Conclusions: Several countermeasures are recommended based on the study findings. The recommended countermeasures focus on the holistic safety improvement strategies constituting the three Es of highway safety, namely, engineering, education, and enforcement.