Motor vehicle-bicycle crashes in Beijing: irregular maneuvers, crash patterns, and injury severity.
Yan, Xinping; Ma, Ming; Huang, Helai; Abdel-Aty, Mohamed; Wu, Chaozhong
2011-09-01
This research presents a comprehensive analysis of motor vehicle-bicycle crashes using 4 years of reported crash data (2004-2007) in Beijing. The interrelationship of irregular maneuvers, crash patterns and bicyclist injury severity are investigated by controlling for a variety of risk factors related to bicyclist demographics, roadway geometric design, road environment, etc. Results show that different irregular maneuvers are correlated with a number of risk factors at different roadway locations such as the bicyclist age and gender, weather and traffic condition. Furthermore, angle collisions are the leading pattern of motor vehicle-bicycle crashes, and different irregular maneuvers may lead to some specific crash patterns such as head-on or rear-end crashes. Orthokinetic scrape is more likely to result in running over bicyclists, which may lead to more severe injury. Moreover, bicyclist injury severity level could be elevated by specific crash patterns and risk factors including head-on and angle collisions, occurrence of running over bicyclists, night without streetlight, roads without median/division, higher speed limit, heavy vehicle involvement and older bicyclists. This study suggests installation of median, division between roadway and bikeway, and improvement of illumination on road segments. Reduced speed limit is also recommended at roadway locations with high bicycle traffic volume. Furthermore, it may be necessary to develop safety campaigns aimed at male, teenage and older bicyclists. Copyright © 2011 Elsevier Ltd. All rights reserved.
A novel approach for analyzing severe crash patterns on multilane highways.
Pande, Anurag; Abdel-Aty, Mohamed
2009-09-01
This study presents a novel approach for analysis of patterns in severe crashes that occur on mid-block segments of multilane highways with partially limited access. A within stratum matched crash vs. non-crash classification approach is adopted towards that end. Under this approach crashes serve as units of analysis and it does not require aggregation of crash data over arterial segments of arbitrary lengths. Also, the proposed approach does not use information on non-severe crashes and hence is not affected by under-reporting of the minor crashes. Random samples of time, day of week, and location (i.e., milepost) combinations were collected for multilane arterials in the state of Florida and matched with severe crashes from the corresponding corridor to form matched strata consisting of severe crash and non-crash cases. For these cases, geometric design/roadside and traffic characteristics were derived based on the corresponding milepost locations. Four groups of crashes, severe rear-end, lane-change related, pedestrian, and single-vehicle/off-road crashes, on multilane arterials segments were compared separately to the non-crash cases. Severe lane-change related crashes may primarily be attributed to exposure while single-vehicle crashes and pedestrian crashes have no significant relationship with the ADT (Average Daily Traffic). For severe rear-end crashes speed limit, ADT, K-factor, time of day/day of week, median type, pavement condition, and presence of horizontal curvature were significant factors. The proposed approach uses general roadway characteristics as independent variables rather than event-specific information (i.e., crash characteristics such as driver/vehicle details); it has the potential to fit within a safety evaluation framework for arterial segments.
Characteristics of cyclist crashes in Italy using latent class analysis and association rule mining
De Angelis, Marco; Marín Puchades, Víctor; Fraboni, Federico; Pietrantoni, Luca
2017-01-01
The factors associated with severity of the bicycle crashes may differ across different bicycle crash patterns. Therefore, it is important to identify distinct bicycle crash patterns with homogeneous attributes. The current study aimed at identifying subgroups of bicycle crashes in Italy and analyzing separately the different bicycle crash types. The present study focused on bicycle crashes that occurred in Italy during the period between 2011 and 2013. We analyzed categorical indicators corresponding to the characteristics of infrastructure (road type, road signage, and location type), road user (i.e., opponent vehicle and cyclist’s maneuver, type of collision, age and gender of the cyclist), vehicle (type of opponent vehicle), and the environmental and time period variables (time of the day, day of the week, season, pavement condition, and weather). To identify homogenous subgroups of bicycle crashes, we used latent class analysis. Using latent class analysis, the bicycle crash data set was segmented into 19 classes, which represents 19 different bicycle crash types. Logistic regression analysis was used to identify the association between class membership and severity of the bicycle crashes. Finally, association rules were conducted for each of the latent classes to uncover the factors associated with an increased likelihood of severity. Association rules highlighted different crash characteristics associated with an increased likelihood of severity for each of the 19 bicycle crash types. PMID:28158296
Brown, J Kristine; Jing, Yuezhou; Wang, Stewart; Ehrlich, Peter F
2006-02-01
Motor vehicle crashes (MVCs) account for 50% of pediatric trauma. Safety improvements are typically tested with child crash dummies using an in vitro model. The Crash Injury Research Engineering Network (CIREN) provides an in vivo validation process. Previous research suggest that children in lateral crashes or front-seat locations have higher Injury Severity Scale scores and lower Glasgow Coma Scale scores than those in frontal-impact crashes. However, specific injury patterns and crash characteristics have not been characterized. Data were collected from the CIREN multidisciplinary crash reconstruction network (10 pediatric trauma centers). Injuries were examined with regard to crash direction (frontal/lateral), restraint use, seat location, and change in velocity at impact (DeltaV). Injuries were limited to Abbreviated Injury Scale (AIS) scores of 3 or higher and included head, thoracic, abdominal, pelvic, spine, and long bone (orthopedic) injuries. Standard age groupings (0-4, 5-9, 10-14, and 15-18 years) were used. Statistical analyses used Fisher's Exact test and multiple logistic regressions. Four hundred seventeen MVCs with 2500 injuries were analyzed (males = 219, females = 198). Controlling for DeltaV and age, children in lateral-impact crashes (n = 232) were significantly more likely to suffer severe injuries to the head and thorax as compared with children in frontal crashes (n = 185), who were more likely to suffer severe spine and orthopedic injuries. Children in a front-seat (n = 236) vs those in a back-seat (n = 169) position had more injuries to the thoracic (27% vs 17%), abdominal (21% vs 13%), pelvic (11% vs 1%), and orthopedic (28% vs 10%) regions (P < .05 for all). Seat belts were protective for pelvic (5% vs 12% unbelted) and orthopedic (15% vs 40%) injuries (odds ratio = 3, P < .01 for both). A reproducible pattern of injury is noted for children involved in lateral-impact crashes characterized by head and chest injuries. The Injury Severity Scale scores were higher for children in front-seat positions. Increased lateral-impact safety measures such as mandatory side curtain airbags may decrease morbidity. Furthermore, continued public education for positioning children in the back seat of cars is warranted.
Epidemiology of moderate-to-severe injury patterns observed in rollover crashes.
McMurry, Timothy L; Bose, Dipan; Ridella, Stephen A; Eigen, Ana M; Crandall, Jeff R; Kerrigan, Jason R
2016-05-01
Previous epidemiological studies have highlighted the high risk of injury to the head, thorax, and cervical spine in rollover crashes. However, such results provide limited information on whole-body injury distribution and multiple region injury patterns necessary for the improvement and prioritization of rollover-focused injury countermeasures. Sampled cases representing approximately 133,000 U.S. adult occupants involved in rollover crashes (between 1995 and 2013) sustaining moderate-to-severe injuries were selected from the National Automotive Sampling System Crashworthiness Data System database. A retrospective cohort study, based on a survey of population-based data, was used to identify relevant whole body injury patterns. Among belted occupants injured in rollover crashes, 79.2% sustained injuries to only one body region. The three most frequently injured (AIS2+) body regions were head (42.1%), upper extremity (28.0%), and thorax (27.1%). The most frequent multi-region injury pattern involved the head and upper extremity, but this pattern only accounted for 2.3% of all of occupants with moderate or worse injuries. The results indicated that for rollover-dominated crashes, the frequently observed injury patterns involved isolated body regions. In contrast, multi-region injury patterns are more frequently observed in rollovers with significant planar impacts. Identification of region-specific injury patterns in pure rollover crashes is essential for clarifying injury mitigation targets and developing whole-body injury metrics specifically applicable to rollovers. Copyright © 2016 Elsevier Ltd. All rights reserved.
Statewide analysis of bicycle crashes : [project summary].
DOT National Transportation Integrated Search
2017-06-01
An extensive literature review was conducted to locate existing studies in four areas: (1) risk factors that affect the frequency and severity of bicycle crashes; (2) bicycle crash causes, patterns, and contributing factors; (3) network screening met...
Anarkooli, Alireza Jafari; Hosseinpour, Mehdi; Kardar, Adele
2017-09-01
Rollover crashes are responsible for a notable number of serious injuries and fatalities; hence, they are of great concern to transportation officials and safety researchers. However, only few published studies have analyzed the factors associated with severity outcomes of rollover crashes. This research has two objectives. The first objective is to investigate the effects of various factors, of which some have been rarely reported in the existing studies, on the injury severities of single-vehicle (SV) rollover crashes based on six-year crash data collected on the Malaysian federal roads. A random-effects generalized ordered probit (REGOP) model is employed in this study to analyze injury severity patterns caused by rollover crashes. The second objective is to examine the performance of the proposed approach, REGOP, for modeling rollover injury severity outcomes. To this end, a mixed logit (MXL) model is also fitted in this study because of its popularity in injury severity modeling. Regarding the effects of the explanatory variables on the injury severity of rollover crashes, the results reveal that factors including dark without supplemental lighting, rainy weather condition, light truck vehicles (e.g., sport utility vehicles, vans), heavy vehicles (e.g., bus, truck), improper overtaking, vehicle age, traffic volume and composition, number of travel lanes, speed limit, undulating terrain, presence of central median, and unsafe roadside conditions are positively associated with more severe SV rollover crashes. On the other hand, unpaved shoulder width, area type, driver occupation, and number of access points are found as the significant variables decreasing the probability of being killed or severely injured (i.e., KSI) in rollover crashes. Land use and side friction are significant and positively associated only with slight injury category. These findings provide valuable insights into the causes and factors affecting the injury severity patterns of rollover crashes, and thus can help develop effective countermeasures to reduce the severity of rollover crashes. The model comparison results show that the REGOP model is found to outperform the MXL model in terms of goodness-of-fit measures, and also is significantly superior to other extensions of ordered probit models, including generalized ordered probit and random-effects ordered probit (REOP) models. As a result, this research introduces REGOP as a promising tool for future research focusing on crash injury severity. Copyright © 2017 Elsevier Ltd. All rights reserved.
An empirical analysis of farm vehicle crash injury severities on Iowa's public road system.
Gkritza, Konstantina; Kinzenbaw, Caroline R; Hallmark, Shauna; Hawkins, Neal
2010-07-01
Farm vehicle crashes are a major safety concern for farmers as well as all other users of the public road system in agricultural states. Using data on farm vehicle crashes that occurred on Iowa's public roads between 2004 and 2006, we estimate a multinomial logit model to identify crash-, farm vehicle-, and driver-specific factors that determine farm vehicle crash injury severity outcomes. Estimation findings indicate that there are crash patterns (rear-end manner of collision; single-vehicle crash; farm vehicle crossed the centerline or median) and conditions (obstructed vision and crash in rural area; dry road, dark lighting, speed limit 55 mph or higher, and harvesting season), as well as farm vehicle and driver-contributing characteristics (old farm vehicle, young farm vehicle driver), where targeted intervention can help reduce the severity of crash outcomes. Determining these contributing factors and their effect is the first step to identifying countermeasures and safety strategies in a bid to improve transportation safety for all users on the public road system in Iowa as well as other agricultural states. Copyright 2010 Elsevier Ltd. All rights reserved.
Chen, Cong; Zhang, Guohui; Huang, Helai; Wang, Jiangfeng; Tarefder, Rafiqul A
2016-11-01
Rural non-interstate crashes induce a significant amount of severe injuries and fatalities. Examination of such injury patterns and the associated contributing factors is of practical importance. Taking into account the ordinal nature of injury severity levels and the hierarchical feature of crash data, this study employs a hierarchical ordered logit model to examine the significant factors in predicting driver injury severities in rural non-interstate crashes based on two-year New Mexico crash records. Bayesian inference is utilized in model estimation procedure and 95% Bayesian Credible Interval (BCI) is applied to testing variable significance. An ordinary ordered logit model omitting the between-crash variance effect is evaluated as well for model performance comparison. Results indicate that the model employed in this study outperforms ordinary ordered logit model in model fit and parameter estimation. Variables regarding crash features, environment conditions, and driver and vehicle characteristics are found to have significant influence on the predictions of driver injury severities in rural non-interstate crashes. Factors such as road segments far from intersection, wet road surface condition, collision with animals, heavy vehicle drivers, male drivers and driver seatbelt used tend to induce less severe driver injury outcomes than the factors such as multiple-vehicle crashes, severe vehicle damage in a crash, motorcyclists, females, senior drivers, driver with alcohol or drug impairment, and other major collision types. Research limitations regarding crash data and model assumptions are also discussed. Overall, this research provides reasonable results and insight in developing effective road safety measures for crash injury severity reduction and prevention. Copyright © 2016 Elsevier Ltd. All rights reserved.
Dynamic compositional modeling of pedestrian crash counts on urban roads in Connecticut.
Serhiyenko, Volodymyr; Ivan, John N; Ravishanker, Nalini; Islam, Md Saidul
2014-03-01
Uncovering the temporal trend in crash counts provides a good understanding of the context for pedestrian safety. With a rareness of pedestrian crashes it is impossible to investigate monthly temporal effects with an individual segment/intersection level data, thus the time dependence should be derived from the aggregated level data. Most previous studies have used annual data to investigate the differences in pedestrian crashes between different regions or countries in a given year, and/or to look at time trends of fatal pedestrian injuries annually. Use of annual data unfortunately does not provide sufficient information on patterns in time trends or seasonal effects. This paper describes statistical methods uncovering patterns in monthly pedestrian crashes aggregated on urban roads in Connecticut from January 1995 to December 2009. We investigate the temporal behavior of injury severity levels, including fatal (K), severe injury (A), evident minor injury (B), and non-evident possible injury and property damage only (C and O), as proportions of all pedestrian crashes in each month, taking into consideration effects of time trend, seasonal variations and VMT (vehicle miles traveled). This type of dependent multivariate data is characterized by positive components which sum to one, and occurs in several applications in science and engineering. We describe a dynamic framework with vector autoregressions (VAR) for modeling and predicting compositional time series. Combining these predictions with predictions from a univariate statistical model for total crash counts will then enable us to predict pedestrian crash counts with the different injury severity levels. We compare these predictions with those obtained from fitting separate univariate models to time series of crash counts at each injury severity level. We also show that the dynamic models perform better than the corresponding static models. We implement the Integrated Nested Laplace Approximation (INLA) approach to enable fast Bayesian posterior computation. Taking CO injury severity level as a baseline for the compositional analysis, we conclude that there was a noticeable shift in the proportion of pedestrian crashes from injury severity A to B, while the increase for injury severity K was extremely small over time. This shift to the less severe injury level (from A to B) suggests that the overall safety on urban roads in Connecticut is improving. In January and February, there was some increase in the proportions for levels A and B over the baseline, indicating a seasonal effect. We found evidence that an increase in VMT would result in a decrease of proportions over the baseline for all injury severity levels. Our dynamic model uncovered a decreasing trend in all pedestrian crash counts before April 2005, followed by a noticeable increase and a flattening out until the end of the fitting period. This appears to be largely due to the behavior of injury severity level A pedestrian crashes. Copyright © 2013 Elsevier Ltd. All rights reserved.
Ehrlich, Peter F; Brown, J Kristine; Sochor, Mark R; Wang, Stewart C; Eichelberger, Martin E
2006-11-01
Motor vehicle crashes account for more than 50% of pediatric injuries. Triage of pediatric patients to appropriate centers can be based on the crash/injury characteristics. Pediatric motor vehicle crash/injury characteristics can be determined from an in vitro laboratory using child crash dummies. However, to date, no detailed data with respect to outcomes and crash mechanism have been presented with a pediatric in vivo model. The Crash Injury Research Engineering Network is comprised of 10 level 1 trauma centers. Crashes were examined with regard to age, crash severity (DeltaV), crash direction, restraint use, and airbag deployment. Multiple logistic regression analysis was performed with Injury Severity Score (ISS) and Glasgow Coma Scale (GCS) as outcomes. Standard age groupings (0-4, 5-9, 10-14, and 15-18) were used. The database is biases toward a survivor population with few fatalities. Four hundred sixty-one motor vehicle crashes with 2500 injuries were analyzed (242 boys, 219 girls). Irrespective of age, DeltaV > 30 mph resulted in increased ISS and decreased GCS (eg, for 0-4 years, DeltaV < 30: ISS = 10, GCS = 13.5 vs DeltaV > 30: ISS = 19.5, GCS = 10.6; P < .007, < .002, respectively). Controlling for DeltaV, children in lateral crashes had increased ISS and decreased GCS versus those in frontal crashes. Airbag deployment was protective for children 15 to 18 years old and resulted in a lower ISS and higher GCS (odds ratio, 2.1; 95% confidence interval, 0.9-4.6). Front-seat passengers suffered more severe (ISS > 15) injuries than did backseat passengers (odds ratio, 1.7; 95% confidence interval, 0.7-3.4). A trend was noted for children younger than 12 years sitting in the front seat to have increased ISS and decreased GCS with airbag deployment but was limited by case number. A reproducible pattern of increased ISS and lower GCS characterized by high severity, lateral crashes in children was noted. Further analysis of the specific injuries as a function and the crash characteristic can help guide management and prevention strategies.
Crash scene photography in motor vehicle crashes without air bag deployment.
Newgard, Craig D; Martens, Katherine A; Lyons, Evelyn M
2002-09-01
To determine whether vehicle characteristics, measured using crash scene photography, are associated with anatomic patterns of injury and severity of injury sustained in motor vehicle crashes (MVCs) without air bag deployment. A prospective observational study was conducted over 22 months, using 12 fire departments serving two hospitals. Two vehicle photographs (exterior and interior) were taken at each MVC. Vehicular variables were assigned by grading the photographs with a standardized scoring system, and outcome information on each patient was collected by chart review. Five hundred fifty-nine patients were entered into the study. Frontal crashes and increasing passenger space intrusion (PSI) were associated with head, facial, and lower-extremity injuries, while rear crashes were associated with spinal injuries. Restraint use had a protective effect in head, facial, and upper and lower extremity injuries, yet was associated with higher odds of spinal injury. Lack of restraint use, increasing PSI, and steering wheel deformity were associated with an increased hospital length of stay and hospital charges, yet only steering wheel deformity was associated with increasing injury severity when adjusting for other crash variables. Out-of-hospital variables, as obtained from crash vehicle photography, are associated with injury site, injury severity, hospital length of stay, and hospital charges in patients involved in MVCs without air bag deployment.
Chen, Chen; Anderson, Jason C; Wang, Haizhong; Wang, Yinhai; Vogt, Rachel; Hernandez, Salvador
2017-11-01
Transportation agencies need efficient methods to determine how to reduce bicycle accidents while promoting cycling activities and prioritizing safety improvement investments. Many studies have used standalone methods, such as level of traffic stress (LTS) and bicycle level of service (BLOS), to better understand bicycle mode share and network connectivity for a region. However, in most cases, other studies rely on crash severity models to explain what variables contribute to the severity of bicycle related crashes. This research uniquely correlates bicycle LTS with reported bicycle crash locations for four cities in New Hampshire through geospatial mapping. LTS measurements and crash locations are compared visually using a GIS framework. Next, a bicycle injury severity model, that incorporates LTS measurements, is created through a mixed logit modeling framework. Results of the visual analysis show some geospatial correlation between higher LTS roads and "Injury" type bicycle crashes. It was determined, statistically, that LTS has an effect on the severity level of bicycle crashes and high LTS can have varying effects on severity outcome. However, it is recommended that further analyses be conducted to better understand the statistical significance and effect of LTS on injury severity. As such, this research will validate the use of LTS as a proxy for safety risk regardless of the recorded bicycle crash history. This research will help identify the clustering patterns of bicycle crashes on high-risk corridors and, therefore, assist with bicycle route planning and policy making. This paper also suggests low-cost countermeasures or treatments that can be implemented to address high-risk areas. Specifically, with the goal of providing safer routes for cyclists, such countermeasures or treatments have the potential to substantially reduce the number of fatalities and severe injuries. Published by Elsevier Ltd.
Modeling left-turn crash occurrence at signalized intersections by conflicting patterns.
Wang, Xuesong; Abdel-Aty, Mohamed
2008-01-01
In order to better understand the underlying crash mechanisms, left-turn crashes occurring at 197 four-legged signalized intersections over 6 years were classified into nine patterns based on vehicle maneuvers and then were assigned to intersection approaches. Crash frequency of each pattern was modeled at the approach level by mainly using Generalized Estimating Equations (GEE) with the Negative Binomial as the link function to account for the correlation among the crash data. GEE with a binomial logit link function was also applied for patterns with fewer crashes. The Cumulative Residuals test shows that, for correlated left-turn crashes, GEE models usually outperformed basic Negative Binomial models. The estimation results show that there are obvious differences in the factors that cause the occurrence of different left-turn collision patterns. For example, for each pattern, the traffic flows to which the colliding vehicles belong are identified to be significant. The width of the crossing distance (represented by the number of through lanes on the opposing approach of the left-turning traffic) is associated with more left-turn traffic colliding with opposing through traffic (Pattern 5), but with less left-turning traffic colliding with near-side crossing through traffic (Pattern 8). The safety effectiveness of the left-turning signal is not consistent for different crash patterns; "protected" phasing is correlated with fewer Pattern 5 crashes, but with more Pattern 8 crashes. The study indicates that in order to develop efficient countermeasures for left-turn crashes and improve safety at signalized intersections, left-turn crashes should be considered in different patterns.
Storvik, Steven G; Campbell, Julius Q; Wheeler, Jeffrey B
2017-06-01
Rates of death because of asphyxia in motor vehicle crashes have been previously estimated using county and statewide data sets, but national estimates have not been reported. The literature regarding asphyxia in motor vehicle crashes primarily involves discussions about clinical findings, and crash-related variables have been sparsely reported. The current study calculated a nationwide fatality rate for asphyxia in motor vehicle crashes of 1.4%. Seventeen case studies of asphyxia were also reported providing crash-, vehicle-, and occupant-related variables. These included type of accident, crash severity, seat belt use, containment status, extent of occupant compartment intrusion, height, weight, and injury pattern. The data presented can be used to better understand the injury mechanism, identify risk factors, develop possible protective countermeasures, and create situational awareness for emergency responders and investigators.
Analysis of work zone rear-end crash risk for different vehicle-following patterns.
Weng, Jinxian; Meng, Qiang; Yan, Xuedong
2014-11-01
This study evaluates rear-end crash risk associated with work zone operations for four different vehicle-following patterns: car-car, car-truck, truck-car and truck-truck. The deceleration rate to avoid the crash (DRAC) is adopted to measure work zone rear-end crash risk. Results show that the car-truck following pattern has the largest rear-end crash risk, followed by truck-truck, truck-car and car-car patterns. This implies that it is more likely for a car which is following a truck to be involved in a rear-end crash accident. The statistical test results further confirm that rear-end crash risk is statistically different between any two of the four patterns. We therefore develop a rear-end crash risk model for each vehicle-following pattern in order to examine the relationship between rear-end crash risk and its influencing factors, including lane position, the heavy vehicle percentage, lane traffic flow and work intensity which can be characterized by the number of lane reductions, the number of workers and the amount of equipment at the work zone site. The model results show that, for each pattern, there will be a greater rear-end crash risk in the following situations: (i) heavy work intensity; (ii) the lane adjacent to work zone; (iii) a higher proportion of heavy vehicles and (iv) greater traffic flow. However, the effects of these factors on rear-end crash risk are found to vary according to the vehicle-following patterns. Compared with the car-car pattern, lane position has less effect on rear-end crash risk in the car-truck pattern. The effect of work intensity on rear-end crash risk is also reduced in the truck-car pattern. Copyright © 2014 Elsevier Ltd. All rights reserved.
Database improvements for motor vehicle/bicycle crash analysis
Lusk, Anne C; Asgarzadeh, Morteza; Farvid, Maryam S
2015-01-01
Background Bicycling is healthy but needs to be safer for more to bike. Police crash templates are designed for reporting crashes between motor vehicles, but not between vehicles/bicycles. If written/drawn bicycle-crash-scene details exist, these are not entered into spreadsheets. Objective To assess which bicycle-crash-scene data might be added to spreadsheets for analysis. Methods Police crash templates from 50 states were analysed. Reports for 3350 motor vehicle/bicycle crashes (2011) were obtained for the New York City area and 300 cases selected (with drawings and on roads with sharrows, bike lanes, cycle tracks and no bike provisions). Crashes were redrawn and new bicycle-crash-scene details were coded and entered into the existing spreadsheet. The association between severity of injuries and bicycle-crash-scene codes was evaluated using multiple logistic regression. Results Police templates only consistently include pedal-cyclist and helmet. Bicycle-crash-scene coded variables for templates could include: 4 bicycle environments, 18 vehicle impact-points (opened-doors and mirrors), 4 bicycle impact-points, motor vehicle/bicycle crash patterns, in/out of the bicycle environment and bike/relevant motor vehicle categories. A test of including these variables suggested that, with bicyclists who had minor injuries as the control group, bicyclists on roads with bike lanes riding outside the lane had lower likelihood of severe injuries (OR, 0.40, 95% CI 0.16 to 0.98) compared with bicyclists riding on roads without bicycle facilities. Conclusions Police templates should include additional bicycle-crash-scene codes for entry into spreadsheets. Crash analysis, including with big data, could then be conducted on bicycle environments, motor vehicle potential impact points/doors/mirrors, bicycle potential impact points, motor vehicle characteristics, location and injury. PMID:25835304
Assessment of crash fire hazard of LH sub 2 fueled aircraft
NASA Technical Reports Server (NTRS)
Brewer, G. D.; Wittlin, G.; Versaw, E. F.; Parmley, R.; Cima, R.; Walther, E. G.
1981-01-01
The relative safety of passengers in LH2 - fueled aircraft, as well as the safety of people in areas surrounding a crash scene, has been evaluated in an analytical study. Four representative circumstances were postulated involving a transport aircraft in which varying degrees of severity of damage were sustained. Potential hazard to the passengers and to the surroundings posed by the spilled fuel was evaluated for each circumstance. Corresponding aircraft fueled with liquid methane, Jet A, and JP-4 were also studied in order to make comparisons of the relative safety. The four scenarios which were used to provide a basis for the evaluation included: (1) a small fuel leak internal to the aircraft, (2) a survivable crash in which a significant quantity of fuel is spilled in a radial pattern as a result of impact with a stationary object while taxiing at fairly low speed, (3) a survivable crash in which a significant quantity of fuel is spilled in an axial pattern as a result of impact during landing, and (4) a non-survivable crash in which a massive fuel spill occurs instantaneously.
Car crash and injury among young drivers: contribution of social, circumstantial and car attributes.
Laflamme, L; Vaez, M
2007-03-01
The objective of the study was to assess the independent contribution of individual, car and circumstantial features in severe and fatal car crashes involving young drivers. A prospective longitudinal, register-based cohort study was conducted at national level (in Sweden), in which people born in the years 1970-1972 (n = 334070) were followed up for the period 1988-2000 (aged 16-18 years in 1988) for their first two-car crashes leading to severe or fatal injury. Ten variables descriptive of the driver (sociodemographics), the car (safety level) and the crash have been analysed using multiple logistic regressions for male and female drivers separately, compiling crude and adjusted odds ratios with 95% CI. When controlling for other features, none of the variables descriptive of male and female drivers' socio-demographic characteristics impacts significantly on the odds of being severely injured or dying in a car-to-car crash. After adjustment, significant excess risks are observed for speed limits higher than the lowest one, type of crash other than rear end collision and road and light conditions other than favourable (dry and daylight), for both male and female drivers. For males only, cars from all car safety levels have significantly higher odds than those from the safest category. Among male and female young drivers, class differences in the risk of being severely injured in a traffic injury are substantial. Yet, despite this imbalance, crash characteristics (for males and females) and safety level of the vehicle driven (for males) remain the most determinant factors of crash severity. Understanding the social patterning of road traffic injuries is a challenge for public health and it seems that qualitative and quantitative differences in crash exposure offer part of the explanation. Young drivers from all social groups need, however, to be sensitized to the risk factors.
Chichom-Mefire, Alain; Atashili, Julius; Tsiagadigui, Jean G; Fon-Awah, Clovis; Ngowe-Ngowe, Marcelin
2015-09-18
Low and middle-income countries carry over ninety per cent of the burden of injury related mortality and disability. Motorcycles are gradually becoming a major mode of transportation in Cameroon and other African countries in the absence of an organized public transport. Consequently, the contribution of motorcycle crash to injury-related deaths seems to be on the rise. Currently, data addressing motorcycle crash characteristics, pattern, and severity of motorcycle-related injuries in Cameroon are scarce. We hypothesised that head and limb injuries are the most frequent cause of morbidity and mortality and equally affect riders and pillion passengers. This hospital-based prospective pilot cohort analysis involving 405 motorcycle crashes and 621 injury victims was conducted in Laquintinie Hospital, a large centre located in an urban area in Cameroon. All motorcycle riders and passengers received in the emergency department over a 4 months period with an injury following a traffic related crash were included. Crash characteristics and type, anatomical location and severity of injuries were recorded and analysed comparing the pattern of injuries between riders and pillion passengers involved in motorcyclecrashes. This pilot analysis is expected to propose a snapshot of motorcycle injuries in Douala and will be followed by a larger analysis over a longer period. We recorded a majority of motorcycle versus car and motorcycle versus motorcycle collisions. Most of these crashes occurred over the week-end and in the night. Helmet use was almost inexistent. We observed that females aged above 40 years represented the majority of pillion passengers. This accounted for the sex-ratio of 1.1/1. A total of 1311 injuries were identified in our patients, giving a mean of 2.1 injuries per victim. The head and the limbs were the most affected anatomical areas. Riders carried a higher risk of sustaining an injury to head and neck than pillion passengers. Riders and pillion passengers carried equal risk of injury to the lower limbs. Emergency room mortality was 4.3 % and riders were more likely to die than pillion passengers. This study has identified females aged above 40 years as a special vulnerable group in Douala. It also carries strong messages useful for the implementation of preventive measures and management of patients injured in motorcycle-related crash in general.
Injury patterns and preventability in prehospital motor vehicle crash fatalities in Victoria.
Ryan, Matt; Stella, Julian; Chiu, Herman; Ragg, Michael
2004-08-01
To examine the pattern of anatomical injury in victims of motor vehicle crashes who die prior to reaching hospital. Cases were identified where death was an unexpected outcome. A retrospective review of autopsy case records including police reports, of all persons who died in motor vehicle crashes between 1 January 1998 and 31 December 1999 and underwent full autopsy at the Victorian Institute of Forensic Medicine (VIFM). Those cases where the victim died in the prehospital phase were examined. Abbreviate Injury Scores and Injury Severity Scores were calculated in each case. Bull's probit analysis was used to identify unexpected deaths. There were 352 motor road crash fatalities identified that underwent autopsy at the VIFM in the study period. Two hundred and six of these were prehospital deaths involving motor vehicles, which satisfied specified criteria. 82% (95% CI: 77.7-86.3%) of cases had Abbreviated Injury Scores of 5 (critical) or 6 (incompatible with life). 80.1% (95% CI: 75.7-84.5%) had an Injury Severity Score greater than 40. 36.9% (95% CI: 34.5-39.3%) of cases had the maximum Injury Severity score of 75. 88.8% (95% CI: 85-92.7%) of cases sustained a head injury and 83.9% (95% CI: 79.8-88.2%) a chest injury. Possibly preventable fatality was identified in 30 (14.6% 95% CI: 13.9-15.3%) cases. In motor vehicle crash fatalities, most victims who die before reaching hospital do so because of major injury, with the head and chest the commonest regions involved. A large proportion of these injuries could be considered unsurvivable regardless of treatment. Earlier intervention or retrieval of such patients is unlikely to influence outcome in the majority of cases.
Patterns in deer-related traffic injuries over a decade: the Mayo clinic experience
2010-01-01
Background Our American College of Surgeons Level 1 Trauma Center serves a rural population. As a result, there is a unique set of accidents that are not present in an urban environment such as deer related motor vehicle crashes (dMVC). We characterized injury patterns between motorcycle/all-terrain vehicles (MCC) and automobile (MVC) crashes related to dMVC (deer motor vehicle crash) with the hypotheses that MCC will present with higher Injury Severity Score (ISS) and that it would be related to whether the driver struck the deer or swerved. Methods The records of 157 consecutive patients evaluated at our institution for injury related to dMVC from January 1st, 1997 to December 31st, 2006 were reviewed from our prospectively collected trauma database. Demographic, clinical, and crash specific parameters were abstracted. Injury severity was analyzed by the Abbreviated Injury Scale score for each body region as well as the overall Injury Severity Score (ISS). Results Motorcycle crashes presented with a higher median ISS than MVCs (14 vs 5, p < 0.001). Median Abbreviated Injury Score (AIS) of the spine for MCC riders was higher (3 vs 0, p < 0.001) if they swerved rather than collided. Seventy-seven percent of riders were not wearing a helmet which did not result in a statistically significant increase in median ISS (16 vs 10), head AIS (2 vs 0) or spine AIS (0 vs 0). Within the MVC group, there was no difference between swerving and hitting the deer in any AIS group. Forty-seven percent of drivers were not wearing seat belts which resulted in similar median ISS (6 vs 5) and AIS of all body regions. Conclusions Motorcycle operators suffered higher ISS. There were no significant differences in median ISS if a driver involved in a deer-related motor vehicle crash swerved rather than collided, was helmeted, or restrained. PMID:20716341
Patterns in deer-related traffic injuries over a decade: the Mayo Clinic experience.
Smoot, Dustin L; Zielinski, Martin D; Cullinane, Daniel C; Jenkins, Donald H; Schiller, Henry J; Sawyer, Mark D
2010-08-17
Our American College of Surgeons Level 1 Trauma Center serves a rural population. As a result, there is a unique set of accidents that are not present in an urban environment such as deer related motor vehicle crashes (dMVC). We characterized injury patterns between motorcycle/all-terrain vehicles (MCC) and automobile (MVC) crashes related to dMVC (deer motor vehicle crash) with the hypotheses that MCC will present with higher Injury Severity Score (ISS) and that it would be related to whether the driver struck the deer or swerved. The records of 157 consecutive patients evaluated at our institution for injury related to dMVC from January 1st, 1997 to December 31st, 2006 were reviewed from our prospectively collected trauma database. Demographic, clinical, and crash specific parameters were abstracted. Injury severity was analyzed by the Abbreviated Injury Scale score for each body region as well as the overall Injury Severity Score (ISS). Motorcycle crashes presented with a higher median ISS than MVCs (14 vs 5, p < 0.001). Median Abbreviated Injury Score (AIS) of the spine for MCC riders was higher (3 vs 0, p < 0.001) if they swerved rather than collided. Seventy-seven percent of riders were not wearing a helmet which did not result in a statistically significant increase in median ISS (16 vs 10), head AIS (2 vs 0) or spine AIS (0 vs 0).Within the MVC group, there was no difference between swerving and hitting the deer in any AIS group. Forty-seven percent of drivers were not wearing seat belts which resulted in similar median ISS (6 vs 5) and AIS of all body regions. Motorcycle operators suffered higher ISS. There were no significant differences in median ISS if a driver involved in a deer-related motor vehicle crash swerved rather than collided, was helmeted, or restrained.
Crash sequence based risk matrix for motorcycle crashes.
Wu, Kun-Feng; Sasidharan, Lekshmi; Thor, Craig P; Chen, Sheng-Yin
2018-04-05
Considerable research has been conducted related to motorcycle and other powered-two-wheeler (PTW) crashes; however, it always has been controversial among practitioners concerning with types of crashes should be first targeted and how to prioritize resources for the implementation of mitigating actions. Therefore, there is a need to identify types of motorcycle crashes that constitute the greatest safety risk to riders - most frequent and most severe crashes. This pilot study seeks exhibit the efficacy of a new approach for prioritizing PTW crash causation sequences as they relate to injury severity to better inform the application of mitigating countermeasures. To accomplish this, the present study constructed a crash sequence-based risk matrix to identify most frequent and most severe motorcycle crashes in an attempt to better connect causes and countermeasures of PTW crashes. Although the frequency of each crash sequence can be computed from crash data, a crash severity model is needed to compare the levels of crash severity among different crash sequences, while controlling for other factors that also have effects on crash severity such drivers' age, use of helmet, etc. The construction of risk matrix based on crash sequences involve two tasks: formulation of crash sequence and the estimation of a mixed-effects (ME) model to adjust the levels of severities for each crash sequence to account for other crash contributing factors that would have an effect on the maximum level of crash severity in a crash. Three data elements from the National Automotive Sampling System - General Estimating System (NASS-GES) data were utilized to form a crash sequence: critical event, crash types, and sequence of events. A mixed-effects model was constructed to model the severity levels for each crash sequence while accounting for the effects of those crash contributing factors on crash severity. A total of 8039 crashes involving 8208 motorcycles occurred during 2011 and 2013 were included in this study, weighted to represent 338,655 motorcyclists involved in traffic crashes in three years (2011-2013)(NHTSA, 2013). The top five most frequent and severe types of crash sequences were identified, accounting for 23 percent of all the motorcycle crashes included in the study, and they are (1) run-off-road crashes on the right, and hitting roadside objects, (2) cross-median crashes, and rollover, (3) left-turn oncoming crashes, and head-on, (4) crossing over (passing through) or turning into opposite direction at intersections, and (5) side-impacted. In addition to crash sequences, several other factors were also identified to have effects on crash severity: use of helmet, presence of horizontal curves, alcohol consumption, road surface condition, roadway functional class, and nighttime condition. Copyright © 2018 Elsevier Ltd. All rights reserved.
Multivariate poisson lognormal modeling of crashes by type and severity on rural two lane highways.
Wang, Kai; Ivan, John N; Ravishanker, Nalini; Jackson, Eric
2017-02-01
In an effort to improve traffic safety, there has been considerable interest in estimating crash prediction models and identifying factors contributing to crashes. To account for crash frequency variations among crash types and severities, crash prediction models have been estimated by type and severity. The univariate crash count models have been used by researchers to estimate crashes by crash type or severity, in which the crash counts by type or severity are assumed to be independent of one another and modelled separately. When considering crash types and severities simultaneously, this may neglect the potential correlations between crash counts due to the presence of shared unobserved factors across crash types or severities for a specific roadway intersection or segment, and might lead to biased parameter estimation and reduce model accuracy. The focus on this study is to estimate crashes by both crash type and crash severity using the Integrated Nested Laplace Approximation (INLA) Multivariate Poisson Lognormal (MVPLN) model, and identify the different effects of contributing factors on different crash type and severity counts on rural two-lane highways. The INLA MVPLN model can simultaneously model crash counts by crash type and crash severity by accounting for the potential correlations among them and significantly decreases the computational time compared with a fully Bayesian fitting of the MVPLN model using Markov Chain Monte Carlo (MCMC) method. This paper describes estimation of MVPLN models for three-way stop controlled (3ST) intersections, four-way stop controlled (4ST) intersections, four-way signalized (4SG) intersections, and roadway segments on rural two-lane highways. Annual Average Daily traffic (AADT) and variables describing roadway conditions (including presence of lighting, presence of left-turn/right-turn lane, lane width and shoulder width) were used as predictors. A Univariate Poisson Lognormal (UPLN) was estimated by crash type and severity for each highway facility, and their prediction results are compared with the MVPLN model based on the Average Predicted Mean Absolute Error (APMAE) statistic. A UPLN model for total crashes was also estimated to compare the coefficients of contributing factors with the models that estimate crashes by crash type and severity. The model coefficient estimates show that the signs of coefficients for presence of left-turn lane, presence of right-turn lane, land width and speed limit are different across crash type or severity counts, which suggest that estimating crashes by crash type or severity might be more helpful in identifying crash contributing factors. The standard errors of covariates in the MVPLN model are slightly lower than the UPLN model when the covariates are statistically significant, and the crash counts by crash type and severity are significantly correlated. The model prediction comparisons illustrate that the MVPLN model outperforms the UPLN model in prediction accuracy. Therefore, when predicting crash counts by crash type and crash severity for rural two-lane highways, the MVPLN model should be considered to avoid estimation error and to account for the potential correlations among crash type counts and crash severity counts. Copyright © 2016 Elsevier Ltd. All rights reserved.
Crashes involving motorised rickshaws in urban India: Characteristics and injury patterns
Schmucker, Uli; Dandona, Rakhi; Kumar, G. Anil; Dandona, Lalit
2011-01-01
Introduction Motorised three-wheeled vehicles (motorised rickshaw) are popular in Asian countries including India. This study aims to describe the crash characteristics and injury patterns for motorised rickshaw occupants and the road users hit-by-motorised rickshaw in urban India. Methods Consecutive cases of road traffic crashes involving motorised rickshaw, irrespective of injury severity, whether alive or dead, presenting to the emergency departments of two large government hospitals and three branches of a private hospital in Hyderabad city were recruited. Crash characteristics, details of injuries, injury severity parameters and outcome were documented in detailed interviews. Results A total of 139 (18%) of the 781 participants recruited were injured as a motorised rickshaw occupant (11%) or were hit by a motorised rickshaw (7%) in 114 crashes involving motorised rickshaw. Amongst motorised rickshaw occupants, single-vehicle collisions (54%) were more frequent than multi-vehicle collisions (46%), with overturning of motorised rickshaw in 73% of the single-vehicle collisions. Mortality (12%), the mean Injury Severity Score (5.8) and rate of multiple injured (60%) indicated a substantial trauma load. No significant differences in injury pattern were found between motorised rickshaw occupants and hit-by-motorised rickshaw subjects, with the pattern being similar to that of the pedestrians and two-wheeled vehicle users. With bivariate analysis for motorised rickshaw occupants, the risk of fatal outcome (odds ratio (OR) 2.60, 95% confidence interval (CI): 0.64–10.54), upper limb injury (OR 2.25, 95% CI: 0.94–5.37) and multiple injuries (OR 2.03, 95% CI 0.85–4.83) was high, although not statistically significant in multi-motorised-vehicle collisions as compared with the single-vehicle collisions or overturning. The risk of having multiple injuries (OR 4.55, 95% CI: 1.15–17.95) was significantly higher in motorised rickshaw occupants involved in front collisions. Being a front-seat motorised rickshaw passenger in a vehicle collision increased the risk of having a fatal outcome (OR 7.37, 95% CI: 0.83–65.66) and a Glasgow coma score ≤ 12 (OR 2.21, 95% CI: 0.49–9.89), although not significantly when compared to the back-seat passengers. Conclusion These findings can assist with planning to deal with the consequences and prevention of road traffic injuries due to crashes involving motorised rickshaw, given the high use of these and substantial morbidity of related injuries in India. The need for improved understanding of the risk characteristics of motorised rickshaw is highlighted. PMID:21584976
Pattern of emergency room mortality among road traffic crash victims.
Babalola, Oladimeji Ranti; Oluwadiya, Kehinde; Vrgoč, Goran; Akpati, Ugochukwu; Sindik, Joško; Čoklo, Miran; Marinović, Marin; Bakota, Bore
2015-11-01
Road traffic injuries are a major cause of death in the emergency room. The goal of this study was to highlight the demographic pattern of road traffic-related deaths in the accident and emergency room of a regional trauma centre. This was a 5-year retrospective study in which road traffic-related cases of emergency room mortality between June 2009 and June 2014 were reviewed. A total of 33 road traffic crash-related deaths occurred during this period with a male-to-female ratio of 2.3:1. Most of these patients were pedestrians with severe injuries involving two or more Abbreviated Injury Scale (AIS) coded regions. The mean time between injury and presentation in the first trauma facility was 112.1 (±55.4)min, and between presentation in the emergency room and death was 410 (±645)min. Mangled lower extremity, bilateral long bone lower limb fractures, pelvic injuries, blunt injuries to the chest and abdomen, and cranial fossae fractures were the common injury pattern. Median ISS and NISS in these patients were 22 (interquartile range [IQR]=11) and 25 (IQR=17), respectively. Severe injuries, delayed presentation, multiple referrals and delayed resuscitative measures contribute to road traffic crash-related mortality. Copyright © 2015 Elsevier Ltd. All rights reserved.
Simoni, Payman; Ostendorf, Robert; Cox, Artemus J
2003-01-01
To examine the relationship between the use of restraining devices and the incidence of specific facial fractures in motor vehicle crashes. Retrospective analysis of patients with facial fractures following a motor vehicle crash. University of Alabama at Birmingham Hospital level I trauma center from 1996 to 2000. Of 3731 patients involved in motor vehicle crashes, a total of 497 patients were found to have facial fractures as determined by International Classification of Diseases, Ninth Revision (ICD-9) codes. Facial fractures were categorized as mandibular, orbital, zygomaticomaxillary complex (ZMC), and nasal. Use of seat belts alone was more effective in decreasing the chance of facial fractures in this population (from 17% to 8%) compared with the use of air bags alone (17% to 11%). The use of seat belts and air bags together decreased the incidence of facial fractures from 17% to 5%. Use of restraining devices in vehicles significantly reduces the chance of incurring facial fractures in a severe motor vehicle crash. However, use of air bags and seat belts does not change the pattern of facial fractures greatly except for ZMC fractures. Air bags are least effective in preventing ZMC fractures. Improving the mechanics of restraining devices might be needed to minimize facial fractures.
Kashani, Ali Tavakoli; Besharati, Mohammad Mehdi
2017-06-01
The aim of this study was to uncover patterns of pedestrian crashes. In the first stage, 34,178 pedestrian-involved crashes occurred in Iran during a four-year period were grouped into homogeneous clusters using a clustering analysis. Next, some in-cluster and inter-cluster crash patterns were analysed. The clustering analysis yielded six pedestrian crash groups. Car/van/pickup crashes on rural roads as well as heavy vehicle crashes were found to be less frequent but more likely to be fatal compared to other crash clusters. In addition, after controlling for crash frequency in each cluster, it was found that the fatality rate of each pedestrian age group as well as the fatal crash involvement rate of each driver age group varies across the six clusters. Results of present study has some policy implications including, promoting pedestrian safety training sessions for heavy vehicle drivers, imposing limitations over elderly heavy vehicle drivers, reinforcing penalties toward under 19 drivers and motorcyclists. In addition, road safety campaigns in rural areas may be promoted to inform people about the higher fatality rate of pedestrians on rural roads. The crash patterns uncovered in this study might also be useful for prioritizing future pedestrian safety research areas.
Evacuation pattern analysis of a survivable commercial aircraft crash.
DOT National Transportation Integrated Search
1962-05-01
The evacuation pattern of 99 of 106 survivors of a jet transport crash involving a post crash fire is described, factors possibly effecting the suffocation and ultimate death of 16 passengers are listed and photographs and diagrams are presented.
Anatomy of a system accident: the crash of Avianca Flight 052.
Helmreich, R L
1994-01-01
On January 25, 1990, Avianca Flight 052 crashed after running out of fuel following a missed approach to New York's John F. Kennedy Airport. Weather was poor on the East Coast of the United States that day, and the flight had experienced several holding patterns enroute from Medellín, Colombia, to New York. The accident is analyzed in terms of Helmreich and Foushee's (1993) model of crew performance and Reason's (1990) model of latent pathogens in system operations.
Anatomy of a system accident: The crash of Avianca Flight 052
NASA Technical Reports Server (NTRS)
Helmreich, Robert L.
1994-01-01
On January 25, 1990, Avianca Flight 052 crashed after running out of fuel following a missed approach to New York's John F. Kennedy Airport. Weather was poor on the East Coast of the United States that day, and the flight had experienced several holding patterns enroute from Medellin, Colombia, to New York. The accident is analyzed in terms of Helmreich and Foushee's (1993) model of crew performance and Reason's (1990) model of latent pathogens in system operations.
Wu, Kun-Feng; Donnell, Eric T; Aguero-Valverde, Jonathan
2014-06-01
To approach the goal of "Toward Zero Deaths," there is a need to develop an analysis paradigm to better understand the effects of a countermeasure on reducing the number of severe crashes. One of the goals in traffic safety research is to search for an effective treatment to reduce fatal and major injury crashes, referred to as severe crashes. To achieve this goal, the selection of promising countermeasures is of utmost importance, and relies on the effectiveness of candidate countermeasures in reducing severe crashes. Although it is important to precisely evaluate the effectiveness of candidate countermeasures in reducing the number of severe crashes at a site, the current state-of-the-practice often leads to biased estimates. While there have been a few advanced statistical models developed to mitigate the problem in practice, these models are computationally difficult to estimate because severe crashes are dispersed spatially and temporally, and cannot be integrated into the Highway Safety Manual framework, which develops a series of safety performance functions and crash modification factors to predict the number of crashes. Crash severity outcomes are generally integrated into the Highway Safety Manual using deterministic distributions rather than statistical models. Accounting for the variability in crash severity as a function geometric design, traffic flow, and other roadway and roadside features is afforded by estimating statistical models. Therefore, there is a need to develop a new analysis paradigm to resolve the limitations in the current Highway Safety Manual methods. We propose an approach which decomposes the severe crash frequency into a function of the change in the total number of crashes and the probability of a crash becoming a severe crash before and after a countermeasure is implemented. We tested this approach by evaluating the effectiveness of shoulder rumble strips on reducing the number of severe crashes. A total of 310 segments that have had shoulder rumble strips installed during 2002-2009 are included in the analysis. It was found that shoulder rumble strips reduce the total number of crashes, but have no statistically significant effect on reducing the probability of a severe crash outcome. Copyright © 2014 Elsevier Ltd. All rights reserved.
Weather impacts on single-vehicle truck crash injury severity.
Naik, Bhaven; Tung, Li-Wei; Zhao, Shanshan; Khattak, Aemal J
2016-09-01
The focus of this paper is on illustrating the feasibility of aggregating data from disparate sources to investigate the relationship between single-vehicle truck crash injury severity and detailed weather conditions. Specifically, this paper presents: (a) a methodology that combines detailed 15-min weather station data with crash and roadway data, and (b) an empirical investigation of the effects of weather on crash-related injury severities of single-vehicle truck crashes. Random parameters ordinal and multinomial regression models were used to investigate crash injury severity under different weather conditions, taking into account the individual unobserved heterogeneity. The adopted methodology allowed consideration of environmental, roadway, and climate-related variables in single-vehicle truck crash injury severity. Results showed that wind speed, rain, humidity, and air temperature were linked with single-vehicle truck crash injury severity. Greater recorded wind speed added to the severity of injuries in single-vehicle truck crashes in general. Rain and warmer air temperatures were linked to more severe crash injuries in single-vehicle truck crashes while higher levels of humidity were linked to less severe injuries. Random parameters ordered logit and multinomial logit, respectively, revealed some individual heterogeneity in the data and showed that integrating comprehensive weather data with crash data provided useful insights into factors associated with single-vehicle truck crash injury severity. The research provided a practical method that combined comprehensive 15-min weather station data with crash and roadway data, thereby providing useful insights into crash injury severity of single-vehicle trucks. Those insights are useful for future truck driver educational programs and for truck safety in different weather conditions. Copyright © 2016 Elsevier Ltd and National Safety Council. All rights reserved.
Oxley, Jennifer; Ravi, Mano Deepa; Yuen, Jeremy; Hoareau, Effie; Hashim, Hizal Hanis
2013-01-01
In Malaysia, motorcycle crashes constitute approximately 60 percent of all road trauma, and a substantial proportion involve children 16 years and younger. There are, however, many gaps in our knowledge on contributing factors to crashes and injury patterns amongst children killed and seriously injured in motorcycle crashes. The aim of this study was to examine fatal and serious injury motorcycle-related collisions to identify contributing factors and injury patterns amongst child motorcyclists. All identified motorcyclist fatal crashes between 2007 and 2011 (inclusive) were extracted from the national Police-reported crash database (M-ROADS) and a range of variables were selected for examination. A total of 17,677 crashes were extracted where a rider or pillion was killed and of these crashes 2,038 involved children, equating to 12 percent. Examination of crashes involving children revealed that some crashes involved more than two children on the motorcycle, therefore, overall children constituted 9.5% of fatal and 18.4% of serious injury collisions. A high proportion of child fatal or serious injury collisions involved the child as the rider (62%), and this was most common for children aged between 10 and 16 years. The majority of collisions occurred on rural roads, in speed limit zones of 50–70km/h, and approximately one-third occurred at an intersection. Collisions involving another motorcycle or a passenger vehicle contributed to 41% and 53% of the total fatalities and severe injuries, respectively. A high proportion (43.9%) of the children (25.5% riders and 18.8% pillion) sustained head injuries with 37.7% being in the 10–16 age group. Furthermore, 52.4% of the children sustaining head injuries did not wear a helmet. The implications of these findings for countermeasures within a Safe System framework, particularly interventions aimed at reducing the rate of unlicensed riding and helmet wearing, and infrastructure countermeasures are discussed. PMID:24406968
Stigson, H
2009-06-01
The objective in this study, using data from crashed cars fitted with on-board crash pulse recorders, was to present differences in average crash severity, distribution of crash severity, and injury outcomes, based on an independent safety rating of roads, also taking road type and speed limit into consideration. Furthermore, the objective was to evaluate differences in injury risk, based on the distribution of crash severity. The investigation included both frontal two-vehicle crashes and single-vehicle crashes with known injury outcome. In total, 209 real-world crashes involving cars fitted with crash pulse recorders were included. For all crashes, average mean acceleration and change of velocity of the vehicle acceleration pulse were measured and calculated. All crash spots were classified according to an independent road safety rating program (European Road Assessment Programme Road Protection Score), where the safety quality of roads is rated in relation to posted speed limits. The crash severity and injury outcome in crashes that occurred on roads with good safety ratings were compared with crashes on roads with poor safety ratings. The data were also divided into subcategories according to posted speed limit and road type, to evaluate whether there was a difference in crash severity and injury outcome within the categories. In total, crash severity was statistically significantly lower in crashes occurring on roads with good safety ratings than in crashes occurring on roads with poor safety ratings. It was found that crash severity and injury risk were lower on roads with good safety ratings with a speed limit of above 90 km/h compared with roads with poor safety ratings, irrespective of speed limit. On the other hand, crash severity was higher on roads with good safety ratings with speed limit of 70 km/h than on roads with poor safety ratings with the same speed limit. Though it was found that a higher speed limit resulted in higher crash severity on roads with poor safety ratings, the opposite was found on roads with good safety ratings. The main reason for this was that lanes for traffic traveling in opposite directions were more often separated at higher speeds on roads with good safety ratings. On divided roads with good safety ratings, there were no crashes resulting in crash severity above the level corresponding to a 10 percent risk of sustaining serious or fatal injury. This indicates that one of the most important safety measures is divided roads.
Zhang, Guangnan; Li, Yanyan; King, Mark J; Zhong, Qiaoting
2018-03-21
Motor vehicle overloading is correlated with the possibility of road crash occurrence and severity. Although overloading of motor vehicles is pervasive in developing nations, few empirical analyses have been performed on factors that might influence the occurrence of overloading. This study aims to address this shortcoming by seeking evidence from several years of crash data from Guangdong province, China. Data on overloading and other factors are extracted for crash-involved vehicles from traffic crash records for 2006-2010 provided by the Traffic Management Bureau in Guangdong province. Logistic regression is applied to identify risk factors for overloading in crash-involved vehicles and within these crashes to identify factors contributing to greater crash severity. Driver, vehicle, road and environmental characteristics and violation types are considered in the regression models. In addition to the basic logistic models, association analysis is employed to identify the potential interactions among different risk factors during fitting the logistic models of overloading and severity. Crash-involved vehicles driven by males from rural households and in an unsafe condition are more likely to be overloaded and to be involved in higher severity overloaded vehicle crashes. If overloaded vehicles speed, the risk of severe traffic crash casualties increases. Young drivers (aged under 25 years) in mountainous areas are more likely to be involved in higher severity overloaded vehicle crashes. This study identifies several factors associated with overloading in crash-involved vehicles and with higher severity overloading crashes and provides an important reference for future research on those specific risk factors. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
Orzechowski, Kelly M; Edgerton, Elizabeth A; Bulas, Dorothy I; McLaughlin, Patrick M; Eichelberger, Martin R
2003-06-01
Injury patterns among children in frontal collisions have been well documented, but little information exists regarding injuries to children in side impact collisions. Restrained children 14-years-old or younger admitted to the hospital for crash injuries were analyzed. Data concerning injuries, medical treatment, and outcome were correlated with crash data. Case reviews achieved consensus regarding injury contact points. Side impacts were compared with frontal impacts. These results were then compared with data from the National Automotive Sampling System. There were no differences between the groups with respect to age, sex, restraint type, or seat position. Compared with frontal crashes, children in side impacts were more likely to have an Injury Severity Score > 15 (odds ratio [OR], 3.1; 95% confidence interval [CI], 1.7-5.8) and were more likely to have Abbreviated Injury Scale score 2+ injuries to the head (OR, 2.5; 95% CI, 1.4-4.4), chest (OR, 4.0; 95% CI, 2.0-8.0), and cervical spine (OR, 3.7; 95% CI, 1.2-11.3). When compared with National Automotive Sampling System data, similar trends were seen regarding Abbreviated Injury Scale score 2+ injuries to the head, chest, and extremities. In this study population, side impacts resulted in more injuries to the head, cervical spine, and chest. Knowledge of this pattern-the side impact syndrome-can help guide diagnosis, treatment, and prevention strategy.
How safe is tuning a radio?: using the radio tuning task as a benchmark for distracted driving.
Lee, Ja Young; Lee, John D; Bärgman, Jonas; Lee, Joonbum; Reimer, Bryan
2018-01-01
Drivers engage in non-driving tasks while driving, such as interactions entertainment systems. Studies have identified glance patterns related to such interactions, and manual radio tuning has been used as a reference task to set an upper bound on the acceptable demand of interactions. Consequently, some view the risk associated with radio tuning as defining the upper limit of glance measures associated with visual-manual in-vehicle activities. However, we have little knowledge about the actual degree of crash risk that radio tuning poses and, by extension, the risk of tasks that have similar glance patterns as the radio tuning task. In the current study, we use counterfactual simulation to take the glance patterns for manual radio tuning tasks from an on-road experiment and apply these patterns to lead-vehicle events observed in naturalistic driving studies. We then quantify how often the glance patterns from radio tuning are associated with rear-end crashes, compared to driving only situations. We used the pre-crash kinematics from 34 crash events from the SHRP2 naturalistic driving study to investigate the effect of radio tuning in crash-imminent situations, and we also investigated the effect of radio tuning on 2,475 routine braking events from the Safety Pilot project. The counterfactual simulation showed that off-road glances transform some near-crashes that could have been avoided into crashes, and glance patterns observed in on-road radio tuning experiment produced 2.85-5.00 times more crashes than baseline driving. Copyright © 2017 Elsevier Ltd. All rights reserved.
Impact of roadway geometric features on crash severity on rural two-lane highways.
Haghighi, Nima; Liu, Xiaoyue Cathy; Zhang, Guohui; Porter, Richard J
2018-02-01
This study examines the impact of a wide range of roadway geometric features on the severity outcomes of crashes occurred on rural two-lane highways. We argue that crash data have a hierarchical structure which needs to be addressed in modeling procedure. Moreover, most of previous studies ignored the impact of geometric features on crash types when developing crash severity models. We hypothesis that geometric features are more likely to determine crash type, and crash type together with other occupant, environmental and vehicle characteristics determine crash severity outcome. This paper presents an application of multilevel models to successfully capture both hierarchical structure of crash data and indirect impact of geometric features on crash severity. Using data collected in Illinois from 2007 to 2009, multilevel ordered logit model is developed to quantify the impact of geometric features and environmental conditions on crash severity outcome. Analysis results revealed that there is a significant variation in severity outcomes of crashes occurred across segments which verifies the presence of hierarchical structure. Lower risk of severe crashes is found to be associated with the presence of 10-ft lane and/or narrow shoulders, lower roadside hazard rate, higher driveway density, longer barrier length, and shorter barrier offset. The developed multilevel model offers greater consistency with data generating mechanism and can be utilized to evaluate safety effects of geometric design improvement projects. Published by Elsevier Ltd.
Injury Risk Functions in Frontal Impacts Using Data from Crash Pulse Recorders
Stigson, Helena; Kullgren, Anders; Rosén, Erik
2012-01-01
Knowledge of how crash severity influences injury risk in car crashes is essential in order to create a safe road transport system. Analyses of real-world crashes increase the ability to obtain such knowledge. The aim of this study was to present injury risk functions based on real-world frontal crashes where crash severity was measured with on-board crash pulse recorders. Results from 489 frontal car crashes (26 models of four car makes) with recorded acceleration-time history were analysed. Injury risk functions for restrained front seat occupants were generated for maximum AIS value of two or greater (MAIS2+) using multiple logistic regression. Analytical as well as empirical injury risk was plotted for several crash severity parameters; change of velocity, mean acceleration and peak acceleration. In addition to crash severity, the influence of occupant age and gender was investigated. A strong dependence between injury risk and crash severity was found. The risk curves reflect that small changes in crash severity may have a considerable influence on the risk of injury. Mean acceleration, followed by change of velocity, was found to be the single variable that best explained the risk of being injured (MAIS2+) in a crash. Furthermore, all three crash severity parameters were found to predict injury better than age and gender. However, age was an important factor. The very best model describing MAIS2+ injury risk included delta V supplemented by an interaction term of peak acceleration and age. PMID:23169136
Comparison of four statistical and machine learning methods for crash severity prediction.
Iranitalab, Amirfarrokh; Khattak, Aemal
2017-11-01
Crash severity prediction models enable different agencies to predict the severity of a reported crash with unknown severity or the severity of crashes that may be expected to occur sometime in the future. This paper had three main objectives: comparison of the performance of four statistical and machine learning methods including Multinomial Logit (MNL), Nearest Neighbor Classification (NNC), Support Vector Machines (SVM) and Random Forests (RF), in predicting traffic crash severity; developing a crash costs-based approach for comparison of crash severity prediction methods; and investigating the effects of data clustering methods comprising K-means Clustering (KC) and Latent Class Clustering (LCC), on the performance of crash severity prediction models. The 2012-2015 reported crash data from Nebraska, United States was obtained and two-vehicle crashes were extracted as the analysis data. The dataset was split into training/estimation (2012-2014) and validation (2015) subsets. The four prediction methods were trained/estimated using the training/estimation dataset and the correct prediction rates for each crash severity level, overall correct prediction rate and a proposed crash costs-based accuracy measure were obtained for the validation dataset. The correct prediction rates and the proposed approach showed NNC had the best prediction performance in overall and in more severe crashes. RF and SVM had the next two sufficient performances and MNL was the weakest method. Data clustering did not affect the prediction results of SVM, but KC improved the prediction performance of MNL, NNC and RF, while LCC caused improvement in MNL and RF but weakened the performance of NNC. Overall correct prediction rate had almost the exact opposite results compared to the proposed approach, showing that neglecting the crash costs can lead to misjudgment in choosing the right prediction method. Copyright © 2017 Elsevier Ltd. All rights reserved.
Richter, Martinus; Pape, Hans-Christoph; Otte, Dietmar; Krettek, Christian
2005-04-01
The purpose of this study was to characterize changes in the mechanism and pattern of injury for vehicular trauma victims with modern vehicle design. Crash and injury severity were specifically investigated to isolate the influence of these improvements in vehicle design. Since 1972, a local, prospective, assessment of vehicular trauma victims on-scene and at medical institutions providing care has been performed including the following parameters: delta-v, collision speed, type of road using, abbreviated injury scale (AIS), injury severity score (ISS), incidence of polytrauma or death. Victims (for restrained car occupants, bicyclists, pedestrians) injured between 1973 and 1978, and between 1994 and 1999 were compared. Lower crash severity (delta-v, collision speed) and injury severity (AIS, ISS, incidence of polytrauma or death) were measured for restrained car occupants, bicyclists and pedestrians during the later period. The correlation coefficient between delta-v or vehicle collision speed and ISS was higher in the earlier period for car occupants, cyclists and pedestrians. This study suggests that the observed reduction in injury severity in restrained car occupants, bicyclists and pedestrians is not only linked to the reduction of crash severity, but also related to improvements in vehicle design beyond seat-belt use. Passive car safety led to decreased injury severity--a comparison.
Lee, Chris; Li, Xuancheng
2014-10-01
This study analyzes driver's injury severity in single- and two-vehicle crashes and compares the effects of explanatory variables among various types of crashes. The study identified factors affecting injury severity and their effects on severity levels using 5-year crash records for provincial highways in Ontario, Canada. Considering heteroscedasticity in the effects of explanatory variables on injury severity, the heteroscedastic ordered logit (HOL) models were developed for single- and two-vehicle crashes separately. The results of the models show that there exists heteroscedasticity for young drivers (≤30), safety equipment and ejection in the single-vehicle crash model, and female drivers, safety equipment and head-on collision in the two-vehicle crash models. The results also show that young car drivers have opposite effects between single-car and car-car crashes, and sideswipe crashes have opposite effects between car-car and truck-truck crashes. The study demonstrates that separate HOL models for single-vehicle and different types of two-vehicle crashes can identify differential effects of factors on driver's injury severity. Copyright © 2014 Elsevier Ltd. All rights reserved.
The impact of Michigan's text messaging restriction on motor vehicle crashes.
Ehsani, Johnathon P; Bingham, C Raymond; Ionides, Edward; Childers, David
2014-05-01
The purpose of this study was to determine the effects of Michigan's universal text messaging restriction (effective July 2010) across different age groups of drivers and crash severities. Changes in monthly crash rates and crash trends per 10,000 licensed drivers aged 16, 17, 18, 19, 20-24, and 25-50 years were estimated using time series analysis for three levels of crash severity: (1) fatal/disabling injury; (2) nondisabling injury; and (3) possible injury/property damage only (PDO) crashes for the period 2005-2012. Analyses were adjusted for crash rates of drivers' aged 65-99 years, Michigan's unemployment rate, and gasoline prices. After the introduction of the texting restriction, significant increases were observed in crash rates and monthly trends in fatal/disabling injury crashes and nondisabling injury crashes, and significant decreases in possible injury/PDO crashes. The magnitude of the effects where significant changes were observed was small. The introduction of the texting restriction was not associated with a reduction in crash rates or trends in severe crash types. On the contrary, small increases in the most severe crash types (fatal/disabling and nondisabling injury) and small decreases in the least severe crash types (possible injury/PDO) were observed. These findings extend the literature on the effects of cell phone restrictions by examining the effects of the restriction on newly licensed adolescent drivers and adult drivers separately by crash severity. Published by Elsevier Inc.
The frequency--severity indeterminacy.
Hauer, Ezra
2006-01-01
Nothing is known about unreported crashes; the information we have is of reported crashes only. Whether a crash gets reported depends on its severity. It follows by logic that, using only data about reported crashes, it is impossible to say whether a change or difference in crash counts reflects a change or difference in crash frequency or in crash severity. This indeterminacy has practical implications. Examples discussed are of the misattribution of over-representation in reported crashes of older drivers and of trucks to causal factors related to the frequency of crash involvement, and of misinterpretation by researchers of findings about the rollover propensity of SUVs.
Cheng, Wen; Gill, Gurdiljot Singh; Sakrani, Taha; Dasu, Mohan; Zhou, Jiao
2017-11-01
Motorcycle crashes constitute a very high proportion of the overall motor vehicle fatalities in the United States, and many studies have examined the influential factors under various conditions. However, research on the impact of weather conditions on the motorcycle crash severity is not well documented. In this study, we examined the impact of weather conditions on motorcycle crash injuries at four different severity levels using San Francisco motorcycle crash injury data. Five models were developed using Full Bayesian formulation accounting for different correlations commonly seen in crash data and then compared for fitness and performance. Results indicate that the models with serial and severity variations of parameters had superior fit, and the capability of accurate crash prediction. The inferences from the parameter estimates from the five models were: an increase in the air temperature reduced the possibility of a fatal crash but had a reverse impact on crashes of other severity levels; humidity in air was not observed to have a predictable or strong impact on crashes; the occurrence of rainfall decreased the possibility of crashes for all severity levels. Transportation agencies might benefit from the research results to improve road safety by providing motorcyclists with information regarding the risk of certain crash severity levels for special weather conditions. Copyright © 2017 Elsevier Ltd. All rights reserved.
Liu, Jun; Khattak, Asad J; Richards, Stephen H; Nambisan, Shashi
2015-12-01
Crashes at highway-rail grade crossings can result in severe injuries and fatalities to vehicle occupants. Using a crash database from the Federal Railroad Administration (N=15,639 for 2004-2013), this study explores differences in safety outcomes from crashes between passive controls (Crossbucks and STOP signs) and active controls (flashing lights, gates, audible warnings and highway signals). To address missing data, an imputation model is developed, creating a complete dataset for estimation. Path analysis is used to quantify the direct and indirect associations of passive and active controls with pre-crash behaviors and crash outcomes in terms of injury severity. The framework untangles direct and indirect associations of controls by estimating two models, one for pre-crash driving behaviors (e.g., driving around active controls), and another model for injury severity. The results show that while the presence of gates is not directly associated with injury severity, the indirect effect through stopping behavior is statistically significant (95% confidence level) and substantial. Drivers are more likely to stop at gates that also have flashing lights and audible warnings, and stopping at gates is associated with lower injury severity. This indirect association lowers the chances of injury by 16%, compared with crashes at crossings without gates. Similar relationships between other controls and injury severity are explored. Generally, crashes occurring at active controls are less severe than crashes at passive controls. The results of study can be used to modify Crash Modification Factors (CMFs) to account for crash injury severity. The study contributes to enhancing the understanding of safety by incorporating pre-crash behaviors in a broader framework that quantifies correlates of crash injury severity at active and passive crossings. Copyright © 2015 Elsevier Ltd. All rights reserved.
Shinar, D; Valero-Mora, P; van Strijp-Houtenbos, M; Haworth, N; Schramm, A; De Bruyne, Guido; Cavallo, V; Chliaoutakis, J; Dias, J; Ferraro, O E; Fyhri, A; Sajatovic, A Hursa; Kuklane, K; Ledesma, R; Mascarell, O; Morandi, A; Muser, M; Otte, D; Papadakaki, M; Sanmartín, J; Dulf, D; Saplioglu, M; Tzamalouka, G
2018-01-01
Police crash reports are often the main source for official data in many countries. However, with the exception of fatal crashes, crashes are often underreported in a biased manner. Consequently, the countermeasures adopted according to them may be inefficient. In the case of bicycle crashes, this bias is most acute and it probably varies across countries, with some of them being more prone to reporting accidents to police than others. Assessing if this bias occurs and the size of it can be of great importance for evaluating the risks associated with bicycling. This study utilized data collected in the COST TU1101 action "Towards safer bicycling through optimization of bicycle helmets and usage". The data came from an online survey that included questions related to bicyclists' attitudes, behaviour, cycling habits, accidents, and patterns of use of helmets. The survey was filled by 8655 bicyclists from 30 different countries. After applying various exclusion factors, 7015 questionnaires filled by adult cyclists from 17 countries, each with at least 100 valid responses, remained in our sample. The results showed that across all countries, an average of only 10% of all crashes were reported to the police, with a wide range among countries: from a minimum of 0.0% (Israel) and 2.6% (Croatia) to a maximum of a 35.0% (Germany). Some factors associated with the reporting levels were type of crash, type of vehicle involved, and injury severity. No relation was found between the likelihood of reporting and the cyclist's gender, age, educational level, marital status, being a parent, use of helmet, and type of bicycle. The significant under-reporting - including injury crashes that do not lead to hospitalization - justifies the use of self-report survey data for assessment of bicycling crash patterns as they relate to (1) crash risk issues such as location, infrastructure, cyclists' characteristics, and use of helmet and (2) strategic approaches to bicycle crash prevention and injury reduction. Copyright © 2017 Elsevier Ltd. All rights reserved.
Hosseinpour, Mehdi; Yahaya, Ahmad Shukri; Sadullah, Ahmad Farhan
2014-01-01
Head-on crashes are among the most severe collision types and of great concern to road safety authorities. Therefore, it justifies more efforts to reduce both the frequency and severity of this collision type. To this end, it is necessary to first identify factors associating with the crash occurrence. This can be done by developing crash prediction models that relate crash outcomes to a set of contributing factors. This study intends to identify the factors affecting both the frequency and severity of head-on crashes that occurred on 448 segments of five federal roads in Malaysia. Data on road characteristics and crash history were collected on the study segments during a 4-year period between 2007 and 2010. The frequency of head-on crashes were fitted by developing and comparing seven count-data models including Poisson, standard negative binomial (NB), random-effect negative binomial, hurdle Poisson, hurdle negative binomial, zero-inflated Poisson, and zero-inflated negative binomial models. To model crash severity, a random-effect generalized ordered probit model (REGOPM) was used given a head-on crash had occurred. With respect to the crash frequency, the random-effect negative binomial (RENB) model was found to outperform the other models according to goodness of fit measures. Based on the results of the model, the variables horizontal curvature, terrain type, heavy-vehicle traffic, and access points were found to be positively related to the frequency of head-on crashes, while posted speed limit and shoulder width decreased the crash frequency. With regard to the crash severity, the results of REGOPM showed that horizontal curvature, paved shoulder width, terrain type, and side friction were associated with more severe crashes, whereas land use, access points, and presence of median reduced the probability of severe crashes. Based on the results of this study, some potential countermeasures were proposed to minimize the risk of head-on crashes. Copyright © 2013 Elsevier Ltd. All rights reserved.
Patterns of abdominal injuries in frontal and side impacts.
Yoganandan, N; Pintar, F A; Gennarelli, T A; Maltese, M R
2000-01-01
Public awareness for safety and vehicle improvements has contributed to significant reduction in injuries secondary to motor vehicle crashes. The spectrum of trauma has shifted from one region of the body to another with varying consequences. For example, airbags have minimized head and neck injuries for adults while emphasizing the lower regions of the human body. Studies have concentrated on the changing patterns of these injuries in frontal impacts. However, there is almost a paucity of data with regard to the characterization of abdominal injuries. Consequently, this study was conducted to determine the patterns of abdominal injuries in frontal and side impacts with an emphasis on more recent crashes. In particular, the frequency and severity of trauma were investigated with a focus on the various abdominal organs (e.g., spleen and liver). Results indicate that side crashes contribute to a large percentage of injuries to the abdomen. The liver and spleen organs are most vulnerable; therefore, it may be beneficial to apply concerted efforts to focus on injury biomechanics research and prioritization activities in these areas of the abdomen. These data may be of benefit to develop anthropomorphic dummies with improved biofidelity.
Investigations of Crashes Involving Pregnant Occupants
Klinich, Kathleen DeSantis; Schneider, Lawrence W.; Moore, Jamie L.; Pearlman, Mark D.
2000-01-01
Case reports of 16 crashes involving pregnant occupants are presented that illustrate the main conclusions of a crash-investigation program that includes 42 crashes investigated to date. Some unusual cases that are exceptions to the overall trends are also described. The study indicates a strong association between adverse fetal outcome and both crash severity and maternal injury. Proper restraint use, with and without airbag deployment, generally leads to acceptable fetal outcomes in lower severity crashes, while it does not affect fetal outcome in high-severity crashes. Compared to properly restrained pregnant occupants, improperly restrained occupants have a higher risk of adverse fetal outcome in lower severity crashes, which comprise the majority of all motor-vehicle collisions. PMID:11558095
Chung, Younshik
2018-02-01
In-vehicle recording devices have enabled recent changes in methodological paradigms for traffic safety research. Such devices include event data recorders (EDRs), vehicle black boxes (VBBs), and various sensors used in naturalistic driving studies (NDSs). These technologies may help improve the validity of models used to assess impacts on traffic safety. The objective of this study is to analyze the injury severity in taxi-pedestrian crashes using the accurate crash data from VBBs, such as the time-to-collision (TTC), speed, angle, and region of the crash. VBB data from a two-year period (2010-2011) were collected from taxis operating in Incheon, South Korea. An ordered probit model was then applied to analyze the injury severity in crashes. Five variables were found to have a greater effect on injury severity: crash speed, crashes in no-median sections, crashes where the secondary impact object of pedestrians was the crash vehicle, crashes where the third impact object of pedestrians was another moving vehicle, and crashes where the third impact region of pedestrians was their head. However, injuries were less severe in crashes where the first impact region on the pedestrian was their leg, crashes with the car moving in a straight line, and crashes involving junior high school students. Copyright © 2017 Elsevier Ltd. All rights reserved.
Chen, Cong; Zhang, Guohui; Liu, Xiaoyue Cathy; Ci, Yusheng; Huang, Helai; Ma, Jianming; Chen, Yanyan; Guan, Hongzhi
2016-12-01
There is a high potential of severe injury outcomes in traffic crashes on rural interstate highways due to the significant amount of high speed traffic on these corridors. Hierarchical Bayesian models are capable of incorporating between-crash variance and within-crash correlations into traffic crash data analysis and are increasingly utilized in traffic crash severity analysis. This paper applies a hierarchical Bayesian logistic model to examine the significant factors at crash and vehicle/driver levels and their heterogeneous impacts on driver injury severity in rural interstate highway crashes. Analysis results indicate that the majority of the total variance is induced by the between-crash variance, showing the appropriateness of the utilized hierarchical modeling approach. Three crash-level variables and six vehicle/driver-level variables are found significant in predicting driver injury severities: road curve, maximum vehicle damage in a crash, number of vehicles in a crash, wet road surface, vehicle type, driver age, driver gender, driver seatbelt use and driver alcohol or drug involvement. Among these variables, road curve, functional and disabled vehicle damage in crash, single-vehicle crashes, female drivers, senior drivers, motorcycles and driver alcohol or drug involvement tend to increase the odds of drivers being incapably injured or killed in rural interstate crashes, while wet road surface, male drivers and driver seatbelt use are more likely to decrease the probability of severe driver injuries. The developed methodology and estimation results provide insightful understanding of the internal mechanism of rural interstate crashes and beneficial references for developing effective countermeasures for rural interstate crash prevention. Copyright © 2016 Elsevier Ltd. All rights reserved.
Impact of pavement conditions on crash severity.
Li, Yingfeng; Liu, Chunxiao; Ding, Liang
2013-10-01
Pavement condition has been known as a key factor related to ride quality, but it is less clear how exactly pavement conditions are related to traffic crashes. The researchers used Geographic Information System (GIS) to link Texas Department of Transportation (TxDOT) Crash Record Information System (CRIS) data and Pavement Management Information System (PMIS) data, which provided an opportunity to examine the impact of pavement conditions on traffic crashes in depth. The study analyzed the correlation between several key pavement condition ratings or scores and crash severity based on a large number of crashes in Texas between 2008 and 2009. The results in general suggested that poor pavement condition scores and ratings were associated with proportionally more severe crashes, but very poor pavement conditions were actually associated with less severe crashes. Very good pavement conditions might induce speeding behaviors and therefore could have caused more severe crashes, especially on non-freeway arterials and during favorable driving conditions. In addition, the results showed that the effects of pavement conditions on crash severity were more evident for passenger vehicles than for commercial vehicles. These results provide insights on how pavement conditions may have contributed to crashes, which may be valuable for safety improvement during pavement design and maintenance. Readers should notice that, although the study found statistically significant effects of pavement variables on crash severity, the effects were rather minor in reality as suggested by frequency analyses. Copyright © 2013 Elsevier Ltd. All rights reserved.
Head impact contact points for restrained child occupants.
Arbogast, Kristy B; Wozniak, Samantha; Locey, Caitlin M; Maltese, Matthew R; Zonfrillo, Mark R
2012-01-01
Head injuries are the most common injuries sustained by children in motor vehicle crashes regardless of age, restraint, and crash direction. For rear seat occupants, the interaction of the subject with the seat back and the vehicle side interior structures has been previously highlighted. In order to advance this knowledge to the development of countermeasures, a summary of vehicle components that contributed to these injuries is needed. Therefore, the objective of this study was to create a contact map of the vehicle interior for head and face injuries to rear-seated restrained children in front crashes. The Crash Injury Research and Engineering Network (CIREN) was queried for rear-seated, restrained child occupants (age 0-15 years) in forward-facing child restraints, booster seats, or lap and shoulder belts who sustained an AIS2+ head and/or face injury in a frontal motor vehicle crash. Cases were analyzed to describe injury patterns and injury causation scenarios. A contact point map was developed to summarize the vehicle components related to injury causation of the head/face injury. Twenty-one cases met the combined inclusion and exclusion criteria. Seven of the child occupants were restrained in forward-facing child restraints, 2 in belt-positioning booster seats, and 12 in lap and shoulder belts. There were 28 head and 17 facial injuries. For left rear occupants, the most common contact point was the pillar in front of the occupant's seat row; that is, B-pillar for second-row occupants, indicating a leftward kinematics. For right rear occupants, due to differences in crash dynamics, the most common contact point location was the passenger's seat back, suggesting that these occupants moved predominantly forward. Contact points associated with head/face injury for restrained children 0 to 15 years in frontal crashes have been delineated. In a majority of the cases, the head/face injury was the most severe injury and severe injuries to other body regions were uncommon, suggesting that efforts to mitigate head injuries for these occupants would greatly improve their overall safety. The majority of the head/face contact points were to the first row seat back and B-pillar. In these frontal crashes, the importance of head/face contact with the vehicle side structure suggests that deploying a curtain air bag in frontal impacts may help manage the energy of impact. These data advance the current understanding of injury patterns and causation in frontal crashes involving restrained rear-row occupants and can be used to develop solutions to mitigate the injuries sustained. Copyright © 2012 Taylor & Francis Group, LLC
Socio-economic analysis of fatal crash trends : final report.
DOT National Transportation Integrated Search
2005-12-01
This report describes the analysis of fatal crash patterns and explores the impact of socioeconomic factors and safety regulations on statewide crash rates. This analysis separated statewide crash rates between 2002 and 2004 into two samples, 1) thos...
Hallman, Jason J; Brasel, Karen J; Yoganandan, Narayan; Pintar, Frank A
2009-10-01
Injury mechanisms from frontal airbags, first identified in anecdotal reports, are now well documented for pediatric, small female, and out-of-position occupants. In contrast, torso side airbags have not yet been consistently associated with specific injury risks in field assessments. To determine possible torso side airbag-related injuries, the present study identified crashes involving side airbags from reports within the CIREN, NASS, and SCI databases. Injury patterns were compared to patterns from lateral crashes in absence of side airbag. Splenic trauma (AIS 3+) was found present in five cases of torso side airbag deployment at lower impact severity (as measured by velocity change and compartment intrusion) than cases of splenic trauma without side airbag. Five additional cases were found to contain similar injury patterns but occurred with greater crash severity. To supplement case analyses, full scale sled tests were conducted with a THOR-NT dummy and cadaveric specimen. Four THOR tests with door- and seat-mounted torso side airbags confirmed that out-of-position (early inflation stage) airbag contact elevated thoracic injury metrics compared to optimal (fully inflated) contact. Out-of-position seat-mounted airbag deployment also produced AIS 3 splenic trauma in the cadaveric specimen. Due to potentially sudden or delayed onset of intraperitoneal hemorrhage and hypovolemic shock following splenic trauma, further biomechanical investigation of this anecdotal evidence is essential to identify injury mechanisms, prevention techniques, and methods for early diagnosis.
Hallman, Jason J.; Brasel, Karen J.; Yoganandan, Narayan; Pintar, Frank A.
2009-01-01
Injury mechanisms from frontal airbags, first identified in anecdotal reports, are now well documented for pediatric, small female, and out-of-position occupants. In contrast, torso side airbags have not yet been consistently associated with specific injury risks in field assessments. To determine possible torso side airbag-related injuries, the present study identified crashes involving side airbags from reports within the CIREN, NASS, and SCI databases. Injury patterns were compared to patterns from lateral crashes in absence of side airbag. Splenic trauma (AIS 3+) was found present in five cases of torso side airbag deployment at lower impact severity (as measured by velocity change and compartment intrusion) than cases of splenic trauma without side airbag. Five additional cases were found to contain similar injury patterns but occurred with greater crash severity. To supplement case analyses, full scale sled tests were conducted with a THOR-NT dummy and cadaveric specimen. Four THOR tests with door- and seat-mounted torso side airbags confirmed that out-of-position (early inflation stage) airbag contact elevated thoracic injury metrics compared to optimal (fully inflated) contact. Out-of-position seat-mounted airbag deployment also produced AIS 3 splenic trauma in the cadaveric specimen. Due to potentially sudden or delayed onset of intraperitoneal hemorrhage and hypovolemic shock following splenic trauma, further biomechanical investigation of this anecdotal evidence is essential to identify injury mechanisms, prevention techniques, and methods for early diagnosis. PMID:20184829
Real-World Rib Fracture Patterns in Frontal Crashes in Different Restraint Conditions.
Lee, Ellen L; Craig, Matthew; Scarboro, Mark
2015-01-01
The purpose of this study was to use the detailed medical injury information in the Crash Injury Research and Engineering Network (CIREN) to evaluate patterns of rib fractures in real-world crash occupants in both belted and unbelted restraint conditions. Fracture patterns binned into rib regional levels were examined to determine normative trends associated with belt use and other possible contributing factors. Front row adult occupants with Abbreviated Injury Scale (AIS) 3+ rib fractures, in frontal crashes with a deployed frontal airbag, were selected from the CIREN database. The circumferential location of each rib fracture (with respect to the sternum) was documented using a previously published method (Ritchie et al. 2006) and digital computed tomography scans. Fracture patterns for different crash and occupant parameters (restraint use, involved physical component, occupant kinematics, crash principal direction of force, and occupant age) were compared qualitatively and quantitatively. There were 158 belted and 44 unbelted occupants included in this study. For belted occupants, fractures were mainly located near the path of the shoulder belt, with the majority of fractures occurring on the inboard (with respect to the vehicle) side of the thorax. For unbelted occupants, fractures were approximately symmetric and distributed across both sides of the thorax. There were negligible differences in fracture patterns between occupants with frontal (0°) and near side (330° to 350° for drivers; 10° to 30° for passengers) crash principal directions of force but substantial differences between groups when occupant kinematics (and contacts within the vehicle) were considered. Age also affected fracture pattern, with fractures tending to occur more anteriorly in older occupants and more laterally in younger occupants (both belted and unbelted). Results of this study confirmed with real-world data that rib fracture patterns in unbelted occupants were more distributed and symmetric across the thorax compared to belted occupants in crashes with a deployed frontal airbag. Other factors, such as occupant kinematics and occupant age, also produced differing patterns of fractures. Normative data on rib fracture patterns in real-world occupants can contribute to understanding injury mechanisms and the role of different causation factors, which can ultimately help prevent fractures and improve vehicle safety.
Rao, Raj D.; Berry, Chirag; Yoganandan, Narayan; Agarwal, Arnav
2016-01-01
Background context Motor vehicle collisions (MVC) are a leading cause of thoracic and lumbar (T and L) spine injuries. Mechanisms of injury in vehicular crashes that result in thoracic and lumbar fractures and the spectrum of injury in these occupants have not been extensively studied in the literature. Purpose The objective was to investigate the patterns of T and L spine injury following MVC; correlate these patterns with restraint use, crash characteristics and demographic variables; and study the associations of these injuries with general injury morbidity and fatality. Study design/Setting Retrospective study of a prospectively gathered database. Patient sample Six hundred and thirty-one occupants with T and L (T1-L5) spine injuries from 4572 occupants included in the Crash Injury Research and Engineering Network (CIREN) database between 1996 and 2011. Outcome measures No clinical outcome measures were evaluated in this study. Methods The CIREN database includes moderate to severely injured occupants from MVC involving vehicles manufactured recently. Demographic, injury and crash data from each patient was analyzed for correlations between pattern of T and L spine injury, associated extra-spinal injuries and overall injury severity score (ISS), type and use of seat belts, and other crash characteristics. T and L spine injury pattern was categorized using a modified Denis classification, to include extension injuries as a separate entity. Results T and L spine injuries were identified in 631 of 4572 vehicle occupants, of whom 299 sustained major injuries (including 21 extension injuries) and 332 sustained minor injuries. Flexion-distraction injuries were more prevalent in children and young adults, and extension injuries in older adults (mean age 65.7 years). Occupants with extension injuries had a mean BMI of 36.0 and a fatality rate of 23.8%, much higher than the fatality rate for the entire cohort (10.9%). The most frequent extra-spinal injuries (Abbreviated Injury Scale grade 2 or more) associated with T and L spine injuries involved the chest (seen in 65.6% of 631 occupants). In contrast to occupants with major T and L spine injuries, those with minor T and L spine injuries showed a strikingly greater association with pelvic and abdominal injuries. Occupants with minor T and L spine injuries had a higher mean ISS (27.1) than those with major T and L spine injuries (25.6). Among occupants wearing a three-point seat belt, 35.3% sustained T and L spine injuries, while only 11.6% of the unbelted occupants sustained T and L spine injuries. Three-point belted individuals were more likely to sustain burst fractures, while two-point belted occupants sustained flexion-distraction injuries most often, and unbelted occupants had a predilection for fracture-dislocations of the T and L spine. Three-point seat belts were protective against neurologic injury, higher ISS and fatality. Conclusions T and L spine fracture patterns are influenced by age of occupant and type and use of seat belts. Despite a reduction in overall injury severity and mortality, seat belt use is associated with an increased incidence of T and L spine fractures. Minor T and L spine fractures were associated with an increased likelihood of pelvic and abdominal injuries and higher ISS scores, demonstrating their importance in predicting overall injury severity. Extension injuries occurred in older, obese individuals, and were associated with a high fatality rate. Future advancements in automobile safety engineering should address the need to reduce T and L spine injuries in belted occupants. PMID:24486471
Severe injury in multiple impacts: Analysis of 1997-2015 NASS-CDS.
Viano, David C; Parenteau, Chantal S
2018-07-04
This is a descriptive study of the incidence and risk for severe injury in single-impact and multi-impact crashes by belt use and crash type using NASS-CDS. 1997-2015 NASS-CDS data were used to determine the distribution of crashes by the number of impacts and severe injury (Maximum Abbreviated Injury Score [MAIS] 4+F) to >15-year-old nonejected drivers by seat belt use in 1997+ MY vehicles. It compares the risk for severe injury in a single impact and in crashes involving 2, 3, or 4+ impacts in the collision with a focus on a frontal crash followed by other impacts. Most vehicle crashes involve a single impact (75.4% of 44,889,518 vehicles), followed by 2-impact crashes (19.6%), 3-impact crashes (5.0%) and 4+ impacts (2.6%). For lap-shoulder-belted drivers, the distribution of severe injury was 42.1% in a single impact, 29.3% in 2 impacts, 13.4% in 3 impacts, and 15.1% in 4+ impact crashes. The risk for a belted driver was 0.256 ± 0.031% in a single impact, 0.564 ± 0.079% in 2 impacts, 0.880 ± 0.125% in 3 impacts, and 2.121 ± 0.646% in 4+ impact. The increase in risk from a single crash to multi-impact collisions was statistically significant (P < .001). In a single impact, 53.8% of belted drivers were in a frontal crashes, 22.4% in side crashes, 20% in rear crashes, and 1.7% in rollover crashes. The risk for severe injury was highest in a rollover at 0.677 ± 0.250%, followed by near-side impact at 0.467 ± 0.084% and far-side impact at 0.237 ± 0.071%. Seat belt use was 82.4% effective in preventing severe injury (MAIS 4+F) in a rollover, 47.9% in a near-side impact, and 74.8% in a far-side impact. In 2-impact crashes with a belted driver, the most common sequence was a rear impact followed by a frontal crash at 1,843,506 (21.5%) with a risk for severe injury of 0.100 ± 0.058%. The second most common was a frontal impact followed by another frontal crash at 1,257,264 (14.7%) with a risk of 0.401 ± 0.057%. The risk was 0.658 ± 0.271% in a frontal impact followed by a rear impact. A near-side impact followed by a rear crash had the highest risk for severe injury at 2.073 ± 1.322%. Restraint systems are generally developed for a single crash or sled test. The risk for severe injury was significantly higher in 2-, 3-, and 4+-impact crashes than a single impact. The majority (57.9%) of severe injuries occurred in multi-impact crashes with belted drivers. The evaluation of restraint performance warrants additional study in multi-impact crashes.
Analysis of the frequency and severity of rear-end crashes in work zones.
Qi, Yi; Srinivasan, Raghavan; Teng, Hualiang; Baker, Robert
2013-01-01
The objective of this study was to identify the factors that influence the frequency and severity of rear-end crashes in work zones because rear-end crashes represent a significant proportion of crashes that occur in work zones. Truncated count data models were developed to identify influencing factors on the frequency of read-end crashes in work zones and ordered probit models were developed to evaluate influencing factors on the severity of rear-end crashes in work zones. Most of the variables identified in this study for these 2 models were significant at the 95 percent level. The statistics for models indicate that the 2 developed models are appropriate compared to alternative models. Major findings related to the frequency of rear-end crashes include the following: (1) work zones for capacity and pavement improvements have the highest frequency compared to other types of work zones; (2) work zones controlled by flaggers are associated with more rear-end crashes compared to those controlled by arrow boards; and (3) work zones with alternating one-way traffic tended to have more rear-end crashes compared to those with lane shifts. Major findings related to the severity of the rear-end crashes include the following: (1) rear-end crashes associated with alcohol, night, pedestrians, and roadway defects are more severe, and those associated with careless backing, stalled vehicles, slippery roadways, and misunderstanding flagging signals are less severe; (2) truck involvement and a large number of vehicles in a crash are both associated with increased severity, and (3) rear-end crashes that happened in work zones for bridge, capacity, and pavement are likely to be more severe than others.
Sasidharan, Lekshmi; Donnell, Eric T
2014-10-01
Accurate estimation of the expected number of crashes at different severity levels for entities with and without countermeasures plays a vital role in selecting countermeasures in the framework of the safety management process. The current practice is to use the American Association of State Highway and Transportation Officials' Highway Safety Manual crash prediction algorithms, which combine safety performance functions and crash modification factors, to estimate the effects of safety countermeasures on different highway and street facility types. Many of these crash prediction algorithms are based solely on crash frequency, or assume that severity outcomes are unchanged when planning for, or implementing, safety countermeasures. Failing to account for the uncertainty associated with crash severity outcomes, and assuming crash severity distributions remain unchanged in safety performance evaluations, limits the utility of the Highway Safety Manual crash prediction algorithms in assessing the effect of safety countermeasures on crash severity. This study demonstrates the application of a propensity scores-potential outcomes framework to estimate the probability distribution for the occurrence of different crash severity levels by accounting for the uncertainties associated with them. The probability of fatal and severe injury crash occurrence at lighted and unlighted intersections is estimated in this paper using data from Minnesota. The results show that the expected probability of occurrence of fatal and severe injury crashes at a lighted intersection was 1 in 35 crashes and the estimated risk ratio indicates that the respective probabilities at an unlighted intersection was 1.14 times higher compared to lighted intersections. The results from the potential outcomes-propensity scores framework are compared to results obtained from traditional binary logit models, without application of propensity scores matching. Traditional binary logit analysis suggests that the probability of occurrence of severe injury crashes is higher at lighted intersections compared to unlighted intersections, which contradicts the findings obtained from the propensity scores-potential outcomes framework. This finding underscores the importance of having comparable treated and untreated entities in traffic safety countermeasure evaluations. Copyright © 2014 Elsevier Ltd. All rights reserved.
Influence of pavement condition on horizontal curve safety.
Buddhavarapu, Prasad; Banerjee, Ambarish; Prozzi, Jorge A
2013-03-01
Crash statistics suggest that horizontal curves are the most vulnerable sites for crash occurrence. These crashes are often severe and many involve at least some level of injury due to the nature of the collisions. Ensuring the desired pavement surface condition is one potentially effective strategy to reduce the occurrence of severe accidents on horizontal curves. This study sought to develop crash injury severity models by integrating crash and pavement surface condition databases. It focuses on developing a causal relationship between pavement condition indices and severity level of crashes occurring on two-lane horizontal curves in Texas. In addition, it examines the suitability of the existing Skid Index for safety maintenance of two-lane curves. Significant correlation is evident between pavement condition and crash injury severity on two-lane undivided horizontal curves in Texas. Probability of a crash becoming fatal is appreciably sensitive to certain pavement indices. Data suggested that road facilities providing a smoother and more comfortable ride are vulnerable to severe crashes on horizontal curves. In addition, the study found that longitudinal skid measurement barely correlates with injury severity of crashes occurring on curved portions. The study recommends exploring the option of incorporating lateral friction measurement into Pavement Management System (PMS) databases specifically at curved road segments. Copyright © 2012 Elsevier Ltd. All rights reserved.
Driver air bag effectiveness by severity of the crash.
Segui-Gomez, M
2000-01-01
OBJECTIVES: This analysis provided effectiveness estimates of the driver-side air bag while controlling for severity of the crash and other potential confounders. METHODS: Data were from the National Automotive Sampling System (1993-1996). Injury severity was described on the basis of the Abbreviated Injury Scale, Injury Severity Score, Functional Capacity Index, and survival. Ordinal, linear, and logistic multivariate regression methods were used. RESULTS: Air bag deployment in frontal or near-frontal crashes decreases the probability of having severe and fatal injuries (e.g., Abbreviated Injury Scale score of 4-6), including those causing a long-lasting high degree of functional limitation. However, air bag deployment in low-severity crashes increases the probability that a driver (particularly a woman) will sustain injuries of Abbreviated Injury Scale level 1 to 3. Air bag deployment exerts a net injurious effect in low-severity crashes and a net protective effect in high-severity crashes. The level of crash severity at which air bags are protective is higher for female than for male drivers. CONCLUSIONS: Air bag improvement should minimize the injuries induced by their deployment. One possibility is to raise their deployment level so that they deploy only in more severe crashes. PMID:11029991
Gasoline prices and their relationship to drunk-driving crashes.
Chi, Guangqing; Zhou, Xuan; McClure, Timothy E; Gilbert, Paul A; Cosby, Arthur G; Zhang, Li; Robertson, Angela A; Levinson, David
2011-01-01
This study investigates the relationship between changing gasoline prices and drunk-driving crashes. Specifically, we examine the effects of gasoline prices on drunk-driving crashes in Mississippi by several crash types and demographic groups at the monthly level from 2004 to 2008, a period experiencing great fluctuation in gasoline prices. An exploratory visualization by graphs shows that higher gasoline prices are generally associated with fewer drunk-driving crashes. Higher gasoline prices depress drunk-driving crashes among young and adult drivers, among male and female drivers, and among white and black drivers. Results from negative binomial regression models show that when gas prices are higher, there are fewer drunk-driving crashes, particularly among property-damage-only crashes. When alcohol consumption levels are higher, there are more drunk-driving crashes, particularly fatal and injury crashes. The effects of gasoline prices and alcohol consumption are stronger on drunk-driving crashes than on all crashes. The findings do not vary much across different demographic groups. Overall, gasoline prices have greater effects on less severe crashes and alcohol consumption has greater effects on more severe crashes. Copyright © 2010 Elsevier Ltd. All rights reserved.
Li, Yunjie; Ma, Dongfang; Zhu, Mengtao; Zeng, Ziqiang; Wang, Yinhai
2018-02-01
Identification of the significant factors of traffic crashes has been a primary concern of the transportation safety research community for many years. A fatal-injury crash is a comprehensive result influenced by multiple variables involved at the moment of the crash scenario, the main idea of this paper is to explore the process of significant factors identification from a multi-objective optimization (MOP) standpoint. It proposes a data-driven model which combines the Non-dominated Sorting Genetic Algorithm (NSGA-II) with the Neural Network (NN) architecture to efficiently search for optimal solutions. This paper also defines the index of Factor Significance (F s ) for quantitative evaluation of the significance of each factor. Based on a set of three year data of crash records collected from three main interstate highways in the Washington State, the proposed method reveals that the top five significant factors for a better Fatal-injury crash identification are 1) Driver Conduct, 2) Vehicle Action, 3) Roadway Surface Condition, 4) Driver Restraint and 5) Driver Age. The most sensitive factors from a spatiotemporal perspective are the Hour of Day, Most Severe Sobriety, and Roadway Characteristics. The method and results in this paper provide new insights into the injury pattern of highway crashes and may be used to improve the understanding of, prevention of, and other enforcement efforts related to injury crashes in the future. Copyright © 2017. Published by Elsevier Ltd.
Injury analysis of patients according to impact patterns involved in pedestrian traffic crashes.
Lee, Hee Young; Youk, Hyun; Ii Lee, Jeong; Kang, Chan Young; Kong, Joon Seok; Sung, Sil; Kang, In Hye; Lee, Jung Hun; Kim, Oh Hyun; Jung, Woo Jin; Lee, Kang Hyun; Youn, Young Han; Park, Jong Chan
2018-02-28
In cases of car-to-person pedestrian traffic crashes (PTCs), the principal issue is determining at what point the car collided with the pedestrian. Accordingly, the objective of the present study was to use the medical records of patients injured in PTCs to investigate the characteristics of crash types and the areas and injury severity and to determine whether there are differences in injuries due to the angle, motion, and position at the point of impact. The present study examined 231 PTC patients admitted to the emergency room (ER) between January and December 2014. Electronic medical records from the hospital were used to divide the patient data according to Abbreviated Injury Scale (AIS) codes for injured areas based on sex, age, time of the crash, outcomes after ER treatment, and major symptoms. Among 231 patients, police reports on 67 crash cases, involving 70 people, were obtained with the help of local police departments, and these reports were used to reconstruct details of the actual crash. For statistical analysis, a chi-square test and a one-way analysis of variance calculation were used to compare the Injury Severity Score (ISS) based on groups and stages, with a statistical significance level set to P < .05. With respect to patients who were admitted for PTC, 52.4% were females and 47.6% were males. The frequency of crashes was high in middle-aged and elderly groups, as well as for youths between 10 and 19 years old. With respect to outcomes after ER treatment, discharge to home after symptom improvement was the most common outcome (24.6%). Admissions to the intensive care unit (25.1%) and to the general ward (23.8%) were also high. In terms of major symptoms, the most common injuries were to the head, resulting from a rotatory motion post impact (35.9%), and injuries to the legs, resulting from the impact of a direct collision with an object (25.1%). This study demonstrated that injuries to the chest and abdomen were the most severe in the fender vault group and head and neck injuries were the most severe in the roof vault group. In particular, the Injury Severity Score was highest in the roof vault group.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wenzel, Tom P.
2016-05-20
Previous analyses have indicated that mass reduction is associated with an increase in crash frequency (crashes per VMT), but a decrease in fatality or casualty risk once a crash has occurred, across all types of light-duty vehicles. These results are counter-intuitive: one would expect that lighter, and perhaps smaller, vehicles have better handling and shorter braking distances, and thus should be able to avoid crashes that heavier vehicles cannot. And one would expect that heavier vehicles would have lower risk once a crash has occurred than lighter vehicles. However, these trends occur under several alternative regression model specifications. This reportmore » tests whether these results continue to hold after accounting for crash severity, by excluding crashes that result in relatively minor damage to the vehicle(s) involved in the crash. Excluding non-severe crashes from the initial LBNL Phase 2 and simultaneous two-stage regression models for the most part has little effect on the unexpected relationships observed in the baseline regression models. This finding suggests that other subtle differences in vehicles and/or their drivers, or perhaps biases in the data reported in state crash databases, are causing the unexpected results from the regression models.« less
Sadeghi-Bazargani, Homayoun; Ayubi, Erfan; Azami-Aghdash, Saber; Abedi, Leila; Zemestani, Alireza; Amanati, Louiz; Moosazadeh, Mahmood; Syedi, Naeema; Safiri, Saeid
2016-01-01
Context Despite considerable attention given to health statistics of road traffic crashes (RTCs), the epidemiological aspects of injuries resulting from RTCs are not fully understood in Iran and other developing countries. The aim of this review was to study the epidemiological pattern and issues arising due to RTCs in Iran. Evidence Acquisition The scope of this study involves data from a broad range of published literature on RTCs in Iran. Data collection for this study was conducted by searching for keywords such as traffic accidents, traffic crashes, motorcycle accidents, motorcycle crashes, motorcycle injury, motor vehicle injury, motor vehicle crashes and motor vehicle accidents, Iran and Iranian in various databases such as Embase, PubMed, Google Scholar, Scopus, Magiran, Iranian scientific information database (SID) and IranMedex. Results This study comprised of 95 articles. It is evident from this review that a large number of severe RTCs occur due to collision of two or more vehicles and most of the victims are males aged between 30 and 39 years. Male pedestrian, drivers and passengers are more likely to be severely injured in comparison to females. One of the most prevalent causes of death among adults involved in the RTCs are head injuries and the majority of deaths occur prior to hospitalization. Mortality rates for RTCs are higher in summer, especially during midnight among all age groups. The most common individual and environmental risk factors associated with RTCs include lack of attention, getting trapped in the car, listening to music, fatigue and sleepiness, duration and distance and negligence of seatbelt usage while driving. Conclusions The findings of the current study will be beneficial in prevention of RTCs and its associated complications and hence will be vital for policy makers, health service managers and stakeholders. PMID:27800461
Investigation of the Performance of Safety Systems for Protection of the Elderly
Augenstein, J.; Digges, K; Bahouth, G.; Dalmotas, D.; Perdeck, E.; Stratton, J.
2005-01-01
This study investigates injury occurrence for belted occupants as a function of age. An analysis of NASS/CDS 1997–2003 data was conducted to determine crash involvement rates and injury rates for front seat occupants versus mean occupant age. In frontal and near-side crashes, the average age of MAIS 3+ belted front seat occupants injured in crashes less severe than 15 mph is of the order of 50 years. The average age of the population exposed to crashes less severe than 15 mph is under 40 years old. The crash exposure and frequency if injuries to the elderly were both found to be the highest in low severity crashes. The chest is the most frequent body region injured for the elderly. These findings suggest the need for more benign safety systems to protect the elderly in low severity crashes. Design of safety systems for the elderly should give priority to reducing the chest loading in low severity frontal and near-side crashes. PMID:16179159
Yang, Hongtai; Cherry, Christopher R; Su, Fan; Ling, Ziwen; Pannell, Zane; Li, Yanlai; Fu, Zhijian
2018-05-25
Unreported minor crashes have importance as a surrogate for more serious crashes that require infrastructure, education, and enforcement strategies; and they still inflict damages. To study factors that influence underreporting, cause, and severity of minor crashes; a survey was performed in Kunming and Beijing to collect self-reported personal characteristics and crash history data of the three major urban road users in China: automobile drivers, bicycle riders and electric bike (e-bike) riders. Underreporting rates of automobile to automobile, automobile to non-motorized vehicle, and non-motorized vehicle to non-motorized vehicle crashes are 56%, 77% and 94%, respectively. Minor crashes with higher reported injury severity levels are more likely to be reported. E-bike riders without a driver's license are more likely to cause crashes. Licensing and education could be an effective way to reduce their crashes. The party that is not at fault in a crash is more likely to sustain high level of injury.
Pilot age and error in air taxi crashes.
Rebok, George W; Qiang, Yandong; Baker, Susan P; Li, Guohua
2009-07-01
The associations of pilot error with the type of flight operations and basic weather conditions are well documented. The correlation between pilot characteristics and error is less clear. This study aims to examine whether pilot age is associated with the prevalence and patterns of pilot error in air taxi crashes. Investigation reports from the National Transportation Safety Board for crashes involving non-scheduled Part 135 operations (i.e., air taxis) in the United States between 1983 and 2002 were reviewed to identify pilot error and other contributing factors. Crash circumstances and the presence and type of pilot error were analyzed in relation to pilot age using Chi-square tests. Of the 1751 air taxi crashes studied, 28% resulted from mechanical failure, 25% from loss of control at landing or takeoff, 7% from visual flight rule conditions into instrument meteorological conditions, 7% from fuel starvation, 5% from taxiing, and 28% from other causes. Crashes among older pilots were more likely to occur during the daytime rather than at night and off airport than on airport. The patterns of pilot error in air taxi crashes were similar across age groups. Of the errors identified, 27% were flawed decisions, 26% were inattentiveness, 23% mishandled aircraft kinetics, 15% mishandled wind and/or runway conditions, and 11% were others. Pilot age is associated with crash circumstances but not with the prevalence and patterns of pilot error in air taxi crashes. Lack of age-related differences in pilot error may be attributable to the "safe worker effect."
Neighborhood Influences on Vehicle-Pedestrian Crash Severity.
Toran Pour, Alireza; Moridpour, Sara; Tay, Richard; Rajabifard, Abbas
2017-12-01
Socioeconomic factors are known to be contributing factors for vehicle-pedestrian crashes. Although several studies have examined the socioeconomic factors related to the location of the crashes, limited studies have considered the socioeconomic factors of the neighborhood where the road users live in vehicle-pedestrian crash modelling. This research aims to identify the socioeconomic factors related to both the neighborhoods where the road users live and where crashes occur that have an influence on vehicle-pedestrian crash severity. Data on vehicle-pedestrian crashes that occurred at mid-blocks in Melbourne, Australia, was analyzed. Neighborhood factors associated with road users' residents and location of crash were investigated using boosted regression tree (BRT). Furthermore, partial dependence plots were applied to illustrate the interactions between these factors. We found that socioeconomic factors accounted for 60% of the 20 top contributing factors to vehicle-pedestrian crashes. This research reveals that socioeconomic factors of the neighborhoods where the road users live and where the crashes occur are important in determining the severity of the crashes, with the former having a greater influence. Hence, road safety countermeasures, especially those focussing on the road users, should be targeted at these high-risk neighborhoods.
Spatial patterns monitoring of road traffic injuries in Karachi metropolis.
Lateef, Muhammad U
2011-06-01
This article aims to assess the pattern of road traffic injuries (RTIs) and fatalities in Karachi metropolis. Assessing the pattern of RTIs in Karachi at this juncture is important for many reasons. The rapid motorisation in the recent years due to the availability of credit has significantly increased the traffic volume of the city. Since then, the roads of Karachi have continuously developed at a rapid pace. This development has come with a high human loss, because the construction of multilevel flyovers, signal-free corridors and the resulting high-speed traffic ultimately increase the severity of injuries. The reasons for this high proportion are inadequate infrastructure, poor enforcement of safety regulations, high crash severity index and greater population of vulnerable road user groups (riders and pedestrians). This research is the first of its kind in the country to have a geocoded database of fatalities and injuries in a geographical information system for the entire city of Karachi. In fact, road crashes are both predictable and preventable. Developing countries should learn from the experience of highly motorised nations to avoid the high burden of RTIs by adopting road safety and prevention measures.
Functional recovery patterns in seriously injured automotive crash victims.
McMurry, Timothy L; Poplin, Gerald S; Crandall, Jeff
2016-09-01
The functional capacity index (FCI) is designed to predict functional loss 12 months post-injury for each injury in the 2008 Abbreviated Injury Scale (AIS) manual on a scale from 0 (death) to 100 (full recovery), but FCI has never been validated. This study compared FCI predicted loss with patient-reported 12-month outcomes as measured through the Short Form 36 (SF-36) health assessment survey. Using follow-up data collected on 2,858 adult car crash occupants in the Crash Injury Research and Engineering Network (CIREN) database, we compared FCI predicted outcomes to occupants' Physical Component Summary (PCS) scores, which are weighted averages of the SF-36 items addressing physical function. Our analyses included descriptive statistics, plots of typical recovery patterns, and a mixed effects regression model that describes PCS as a function of FCI, demographics, comorbidities, and injury pattern while also adjusting for the occupants' pre-crash physical capabilities. We further examined injuries in patients who report a significant drop in PCS 12 months post-crash despite being predicted to fully recover. At baseline, the CIREN population exhibited PCS scores similar to the overall population (mean = 51.1, SD = 10.3). Twelve months post-crash, occupants with predicted impairment (FCI < 100) report a substantial decrease in physical function, and those who were predicted to fully recover still report some, albeit less, impairment. In the multivariate mixed-effects regression model, FCI is a strongly significant (P-value <.0001) predictor of PCS, with each 1-point drop in FCI predicting a 0.27-point drop in PCS. Maximum AIS severities in the head, spine, and lower extremity body regions were also significantly associated with PCS (P-values <.05). Among occupants who were expected to fully recover but who report a significant drop in PCS at 12 months, spinal fractures without cord involvement account for 5 of the 10 most common AIS 2+ injuries. FCI was associated with 12-month outcomes but may not adequately describe the recovery from some head, spine, and lower extremity injuries. Some occupants who were expected to recover still report functional loss 12 months post-injury.
Zaloshnja, Eduard; Miller, Ted; Council, Forrest; Persaud, Bhagwant
2004-01-01
This paper presents estimates for both the economic and comprehensive costs per crash for three police-coded severity groupings within 16 selected crash types and within two speed limit categories (
Vehicular crash data used to rank intersections by injury crash frequency and severity.
Liu, Yi; Li, Zongzhi; Liu, Jingxian; Patel, Harshingar
2016-09-01
This article contains data on research conducted in "A double standard model for allocating limited emergency medical service vehicle resources ensuring service reliability" (Liu et al., 2016) [1]. The crash counts were sorted out from comprehensive crash records of over one thousand major signalized intersections in the city of Chicago from 2004 to 2010. For each intersection, vehicular crashes were counted by crash severity levels, including fatal, injury Types A, B, and C for major, moderate, and minor injury levels, property damage only (PDO), and unknown. The crash data was further used to rank intersections by equivalent injury crash frequency. The top 200 intersections with the highest number of crash occurrences identified based on crash frequency- and severity-based scenarios are shared in this brief. The provided data would be a valuable source for research in urban traffic safety analysis and could also be utilized to examine the effectiveness of traffic safety improvement planning and programming, intersection design enhancement, incident and emergency management, and law enforcement strategies.
Zaloshnja, Eduard; Miller, Ted; Council, Forrest; Persaud, Bhagwant
2004-01-01
This paper presents estimates for both the economic and comprehensive costs per crash for three police-coded severity groupings within 16 selected crash types and within two speed limit categories (<=45 and >=50 mph). The economic costs are hard dollar costs. The comprehensive costs include economic costs and quality of life losses. We merged previously developed costs per victim keyed on the Abbreviated Injury Scale (AIS) into US crash data files that scored injuries in both the AIS and police-coded severity scales to produce per crash estimates. The most costly crashes were non-intersection fatal/disabling injury crashes on a road with a speed limit of 50 miles per hour or higher where multiple vehicles crashed head-on or a single vehicle struck a human (over 1.69 and $1.16 million per crash, respectively). The annual cost of police-reported run-off-road collisions, which include both rollovers and object impacts, represented 34% of total costs. PMID:15319129
Median barrier crash severity: some new insights.
Hu, Wen; Donnell, Eric T
2010-11-01
Median barrier is used to prevent cross-median crashes on divided highways. Although it is well documented that crash frequencies increase after installing median barrier, little is known about median barrier crash severity outcomes. The present study estimated a nested logit model of median barrier crash severity using 5 years of data from rural divided highways in North Carolina. Vehicle, driver, roadway, and median cross-section design data were factors considered in the model. A unique aspect of the data used to estimate the model was the availability of median barrier placement and median cross-slope data, two elements not commonly included in roadway inventory data files. The estimation results indicate that collisions with a cable median barrier increase the probability of less-severe crash outcomes relative to collisions with a concrete or guardrail median barrier. Increasing the median barrier offset was associated with a lower probability of severe crash outcomes. The presence of a cable median barrier installed on foreslopes that were between 6H:1V and 10H:1V were associated with an increase in severe crash probabilities when compared to cable median barrier installations on foreslopes that were 10H:1V or flatter. 2010 Elsevier Ltd. All rights reserved.
A hybrid clustering and classification approach for predicting crash injury severity on rural roads.
Hasheminejad, Seyed Hessam-Allah; Zahedi, Mohsen; Hasheminejad, Seyed Mohammad Hossein
2018-03-01
As a threat for transportation system, traffic crashes have a wide range of social consequences for governments. Traffic crashes are increasing in developing countries and Iran as a developing country is not immune from this risk. There are several researches in the literature to predict traffic crash severity based on artificial neural networks (ANNs), support vector machines and decision trees. This paper attempts to investigate the crash injury severity of rural roads by using a hybrid clustering and classification approach to compare the performance of classification algorithms before and after applying the clustering. In this paper, a novel rule-based genetic algorithm (GA) is proposed to predict crash injury severity, which is evaluated by performance criteria in comparison with classification algorithms like ANN. The results obtained from analysis of 13,673 crashes (5600 property damage, 778 fatal crashes, 4690 slight injuries and 2605 severe injuries) on rural roads in Tehran Province of Iran during 2011-2013 revealed that the proposed GA method outperforms other classification algorithms based on classification metrics like precision (86%), recall (88%) and accuracy (87%). Moreover, the proposed GA method has the highest level of interpretation, is easy to understand and provides feedback to analysts.
Large and Small Cars in Real-World Crashes -Patterns of Use, Collision Types and Injury Outcomes
Thomas, Pete; Frampton, Richard
1999-01-01
Previous work examining the effect of vehicle mass has demonstrated the link with occupant injury severity. The principal factor has been related to Newtonian mechanics. This paper analyses data from the UK Co-operative Crash Injury Study and identifies other factors associated with car size. The mass of the car is found to have a predominant effect on injury outcome in frontal collisions only where the effect is seen most in injuries to the head, face and chest. Most fatal casualties in small cars die when in collision with another car in front or side collisions while the key group for large cars is frontal collisions with road-side objects. There are several characteristics of small car occupants that differ from those in large cars including gender, age and vehicle occupancy. New information in the analysis concerns the priorities in casualty reduction between small and large car occupants and the paper argues that vehicle design should take account of this variation to produce vehicles optimised for the complete range of crashes and car occupants.
Pilot Age and Error in Air-Taxi Crashes
Rebok, George W.; Qiang, Yandong; Baker, Susan P.; Li, Guohua
2010-01-01
Introduction The associations of pilot error with the type of flight operations and basic weather conditions are well documented. The correlation between pilot characteristics and error is less clear. This study aims to examine whether pilot age is associated with the prevalence and patterns of pilot error in air-taxi crashes. Methods Investigation reports from the National Transportation Safety Board for crashes involving non-scheduled Part 135 operations (i.e., air taxis) in the United States between 1983 and 2002 were reviewed to identify pilot error and other contributing factors. Crash circumstances and the presence and type of pilot error were analyzed in relation to pilot age using Chi-square tests. Results Of the 1751 air-taxi crashes studied, 28% resulted from mechanical failure, 25% from loss of control at landing or takeoff, 7% from visual flight rule conditions into instrument meteorological conditions, 7% from fuel starvation, 5% from taxiing, and 28% from other causes. Crashes among older pilots were more likely to occur during the daytime rather than at night and off airport than on airport. The patterns of pilot error in air-taxi crashes were similar across age groups. Of the errors identified, 27% were flawed decisions, 26% were inattentiveness, 23% mishandled aircraft kinetics, 15% mishandled wind and/or runway conditions, and 11% were others. Conclusions Pilot age is associated with crash circumstances but not with the prevalence and patterns of pilot error in air-taxi crashes. Lack of age-related differences in pilot error may be attributable to the “safe worker effect.” PMID:19601508
Ahmed, Mohamed M; Franke, Rebecca; Ksaibati, Khaled; Shinstine, Debbie S
2018-08-01
Roadway safety is an integral part of a functioning infrastructure. A major use of the highway system is the transport of goods. The United States has experienced constant growth in the amount of freight transported by truck in the last few years. Wyoming is experiencing a large increase in truck traffic on its local and county roads due to an increase in oil and gas production. This study explores the involvement of heavy trucks in crashes and their significance as a predictor of crash severity and addresses the effect that large truck traffic is having on the safety of roadways for various road classifications. Studies have been done on the factors involved in and the causation of heavy truck crashes, but none address the causation and effect of roadway classifications on truck crashes. Binary Logit Models (BLM) with Bayesian inferences were utilized to classify heavy truck involvement in severe and non-severe crashes using ten years (2002-2011) of historical crash data in the State of Wyoming. From the final main effects model, various interactions proved to be significant in predicting the severity of crashes and varied depending on the roadway classification. The results indicated the odds of a severe crash increase to 2.3 and 4.5 times when a heavy truck is involved on state and interstate highways respectively. The severity of crashes is significantly increased when road conditions were not clear, icy, and during snowy weather conditions. Copyright © 2018 Elsevier Ltd. All rights reserved.
Taxonomy of Older Driver Behaviors and Crash Risk : Appendix C
DOT National Transportation Integrated Search
2012-02-01
This projects objectives were to identify risky behaviors, driving habits, and exposure patterns that have been shown to increase the likelihood of crash involvement among older drivers; and to classify these crash-contributing factors according t...
Comprehensive study to reduce pedestrian crashes in Florida.
DOT National Transportation Integrated Search
2013-12-01
Pedestrian crashes are a major traffic safety concern in Florida. This project aims to improve pedestrian safety on : Floridas state roads by identifying crash patterns and contributing factors at both the statewide and site-specific : level and p...
Taxonomy of Older Driver Behaviors and Crash Risk : Appendix D
DOT National Transportation Integrated Search
2012-02-01
This projects objectives were to identify risky behaviors, driving habits, and exposure patterns that have been shown to increase the likelihood of crash involvement among older drivers; and to classify these crash-contributing factors according t...
2010-01-01
Background Heavy vehicle transportation continues to grow internationally; yet crash rates are high, and the risk of injury and death extends to all road users. The work environment for the heavy vehicle driver poses many challenges; conditions such as scheduling and payment are proposed risk factors for crash, yet the precise measure of these needs quantifying. Other risk factors such as sleep disorders including obstructive sleep apnoea have been shown to increase crash risk in motor vehicle drivers however the risk of heavy vehicle crash from this and related health conditions needs detailed investigation. Methods and Design The proposed case control study will recruit 1034 long distance heavy vehicle drivers: 517 who have crashed and 517 who have not. All participants will be interviewed at length, regarding their driving and crash history, typical workloads, scheduling and payment, trip history over several days, sleep patterns, health, and substance use. All participants will have administered a nasal flow monitor for the detection of obstructive sleep apnoea. Discussion Significant attention has been paid to the enforcement of legislation aiming to deter problems such as excess loading, speeding and substance use; however, there is inconclusive evidence as to the direction and strength of associations of many other postulated risk factors for heavy vehicle crashes. The influence of factors such as remuneration and scheduling on crash risk is unclear; so too the association between sleep apnoea and the risk of heavy vehicle driver crash. Contributory factors such as sleep quality and quantity, body mass and health status will be investigated. Quantifying the measure of effect of these factors on the heavy vehicle driver will inform policy development that aims toward safer driving practices and reduction in heavy vehicle crash; protecting the lives of many on the road network. PMID:20338064
Latent class analysis of factors that influence weekday and weekend single-vehicle crash severities.
Adanu, Emmanuel Kofi; Hainen, Alexander; Jones, Steven
2018-04-01
This paper investigates factors that influence the severity of single-vehicle crashes that happen on weekdays and weekends. Crash data from 2012 to 2016 for the State of Alabama was used for this study. Latent class logit models were developed as alternative to the frequently used random parameters models to account for unobserved heterogeneity across crash-severity observations. Exploration of the data revealed that a high proportion of severe injury injury crashes happened on weekends. The study examined whether single-vehicle crash contributing factors differ between weekdays and weekends. The model estimation results indicate a significant association of severe injury crashes to risk factors such as driver unemployment, driving with invalid license, no seatbelt use, fatigue, driving under influence, old age, and driving on county roads for both weekdays and weekends. Research findings show a strong link between human factors and the occurrence of severe injury single-vehicle crashes, as it has been observed that many of the factors associated with severe-injury outcome are driver behavior related. To illustrate the significance of the findings of this study, a third model using the combined data was developed to explore the merit of using sub-populations of the data for improved and detailed segmentation of the crash-severity factors. It has also been shown that generally, the factors that influence single-vehicle crash injury outcomes were not very different between weekdays and weekends. The findings of this study show the importance of investigating sub-populations of data to reveal complex relationships that should be understood as a necessary step in targeted countermeasure application. Copyright © 2018 Elsevier Ltd. All rights reserved.
Shkrum, Michael J; McClafferty, Kevin J; Nowak, Edwin S; German, Alan
2002-09-01
Assessment of the role of air bag deployment in injury causation in a crash of any severity requires analysis of occupant, vehicle, and impact data. The potential injurious role of an air bag is independent of crash severity and is more obvious in minor collisions, particularly those involving "out-of-position" occupants. Factors such as occupant height and other constitutional and medical factors, intoxication, age, type, and proper use of other restraint systems, pre-impact braking and multiple impacts can contribute to an occupant being "out-of-position." Two injury mechanisms are described in out-of-position occupants: "punch-out" when the individual covers the air bag module before deployment and "membrane-force" when the occupant contacts a partly deployed air bag. Each mechanism is associated with injury patterns. In adults, "punch-out" can cause thoraco-abdominal trauma and "membrane-force" loading can lead to craniocervical injury. This can also occur in short-statured occupants including children subjected to both types of loading. In more severe collisions, other factors, e.g., intrusion, steering column and seatbelt loading and other occupant compartment contacts, can contribute to trauma.
Isaksson-Hellman, Irene; Lindman, Magdalena
2018-02-28
Lane changes, which frequently occur when vehicles travel on major roads, may contribute to critical situations that significantly affect the traffic flow and traffic safety. Thus, knowledge of lane change situations is important for infrastructure improvements as well as for driver support systems and automated driving development projects. The objectives of this study were to evaluate the crash avoidance performance of a lane change driver support system, the Blind Spot Information System (BLIS) in Volvo car models, and to describe the characteristics of lane change crashes by analyzing detailed information from insurance claim reports. An overall evaluation of the safety effect of BLIS was performed by analyzing crash rate differences in lane change situations for cars with and without the optionally mounted BLIS system based on a population of 380,000 insured vehicle years. Further, crashes in which the repair cost of the host vehicle exceeded approximately US$1,250 were selected and compared. Finally, the study examined different precrash factors and crash configurations, using in-depth insurance claims data from representative lane change crash cases including all severity levels in a population of more than 200,000 insured vehicle years. The technology did not significantly reduce the overall number of crashes when all types of lane change crashes and severity levels were considered, though a significant crash-reducing effect of 31% for BLIS cars was found when more severe crashes with a repair cost exceeding US$1,250 were analysed. Cars with the BLIS technology also have a 30% lower claim cost on average for reported lane change crashes, indicating reduced crash severity. When stratifying the data into specific situations, by collecting precrash information in a case-by-case study, the influence of BLIS was indicated to differ for the evaluated situations, although no significant results were found. For example, during general lane change maneuvers (i.e., not while exiting or entering highways or during weaving/merging situations) the crash rate was reduced by 14%, whereas in weaving/merging situations the crash rate increased. The insurance data analyzed provided useful information about real-world lane change crash characteristics by covering collisions in all crash severities and thus revealed information beyond what is available in, for example, data sets of police-reported crashes. This will guide further development of driver support systems. For crashes with repair cost exceeding US$1,250, a significant crash reduction was found, although the technology did not significantly reduce the total number of lane change crashes. An average lower insurance claim cost for cars equipped with the BLIS technology also indicated that the technology contributes to reduced crash severity even if crashes were not totally avoided. Stratifying the data into different lane change crash situations gave indications of the condition-specific performance of the system, even if the results were not statistically significant at the 95% level.
Guo, Qiang; Xu, Pengpeng; Pei, Xin; Wong, S C; Yao, Danya
2017-02-01
Pedestrian safety is increasingly recognized as a major public health concern. Extensive safety studies have been conducted to examine the influence of multiple variables on the occurrence of pedestrian-vehicle crashes. However, the explicit relationship between pedestrian safety and road network characteristics remains unknown. This study particularly focused on the role of different road network patterns on the occurrence of crashes involving pedestrians. A global integration index via space syntax was introduced to quantify the topological structures of road networks. The Bayesian Poisson-lognormal (PLN) models with conditional autoregressive (CAR) prior were then developed via three different proximity structures: contiguity, geometry-centroid distance, and road network connectivity. The models were also compared with the PLN counterpart without spatial correlation effects. The analysis was based on a comprehensive crash dataset from 131 selected traffic analysis zones in Hong Kong. The results indicated that higher global integration was associated with more pedestrian-vehicle crashes; the irregular pattern network was proved to be safest in terms of pedestrian crash occurrences, whereas the grid pattern was the least safe; the CAR model with a neighborhood structure based on road network connectivity was found to outperform in model goodness-of-fit, implying the importance of accurately accounting for spatial correlation when modeling spatially aggregated crash data. Copyright © 2016 Elsevier Ltd. All rights reserved.
"Crashing the gates" - selection criteria for television news reporting of traffic crashes.
De Ceunynck, Tim; De Smedt, Julie; Daniels, Stijn; Wouters, Ruud; Baets, Michèle
2015-07-01
This study investigates which crash characteristics influence the probability that the crash is reported in the television news. To this purpose, all news items from the period 2006-2012 about traffic crashes from the prime time news of two Belgian television channels are linked to the official injury crash database. Logistic regression models are built for the database of all injury crashes and for the subset of fatal crashes to identify crash characteristics that correlate with a lower or higher probability of being reported in the news. A number of significant biases in terms of crash severity, time, place, types of involved road users and victims' personal characteristics are found in the media reporting of crashes. More severe crashes are reported in the media more easily than less severe crashes. Significant fluctuations in media reporting probability through time are found in terms of the year and month in which the crash took place. Crashes during week days are generally less reported in the news. The geographical area (province) in which the crash takes place also has a significant impact on the probability of being reported in the news. Crashes on motorways are significantly more represented in the news. Regarding the age of the involved victims, a clear trend of higher media reporting rates of crashes involving young victims or young fatalities is observed. Crashes involving female fatalities are also more frequently reported in the news. Furthermore, crashes involving a bus have a significantly higher probability of being reported in the news, while crashes involving a motorcycle have a significantly lower probability. Some models also indicate a lower reporting rate of crashes involving a moped, and a higher reporting rate of crashes involving heavy goods vehicles. These biases in media reporting can create skewed perceptions in the general public about the prevalence of traffic crashes and eventually may influence people's behaviour. Copyright © 2015 Elsevier Ltd. All rights reserved.
Cost of Crashes Related to Road Conditions, United States, 2006
Zaloshnja, Eduard; Miller, Ted R.
2009-01-01
This is the first study to estimate the cost of crashes related to road conditions in the U.S. To model the probability that road conditions contributed to the involvement of a vehicle in the crash, we used 2000–03 Large Truck Crash Causation Study (LTCCS) data, the only dataset that provides detailed information whether road conditions contributed to crash occurrence. We applied the logistic regression results to a costed national crash dataset in order to calculate the probability that road conditions contributed to the involvement of a vehicle in each crash. In crashes where someone was moderately to seriously injured (AIS-2-6) in a vehicle that harmfully impacted a large tree or medium or large non-breakaway pole, or if the first harmful event was collision with a bridge, we changed the calculated probability of being road-related to 1. We used the state distribution of costs of fatal crashes where road conditions contributed to crash occurrence or severity to estimate the respective state distribution of non-fatal crash costs. The estimated comprehensive cost of traffic crashes where road conditions contributed to crash occurrence or severity was $217.5 billion in 2006. This represented 43.6% of the total comprehensive crash cost. The large share of crash costs related to road design and conditions underlines the importance of these factors in highway safety. Road conditions are largely controllable. Road maintenance and upgrading can prevent crashes and reduce injury severity. PMID:20184840
The Effect of Booster Seat Use on Pediatric Injuries in Motor Vehicle Frontal Crashes.
Caskey, Sean; Hammond, Joshua; Peck, Jeffery; Sardelli, Matthew; Atkinson, Theresa
2018-04-20
Motor vehicle crashes are a significant source of pediatric mortality and morbidity. Studies indicate that booster seats significantly improve seat belt fit for children who have not attained a height of 145 cm (4' 9"). This study examined injuries occurring in booster age children up to age 12, as the majority of children do not attain 145 cm until this age. The purpose of the study was to identify differences in injuries due to the type of restraint used, with attention to musculoskeletal injuries. Vehicle and occupant data were obtained from a publically available statistical sample of tow-away crashes. Frontal crashes over an 8-year period were examined. A data set of cases was created involving children ages 5 to 12 years who were unrestrained, restrained using the vehicle's lap and shoulder belt, and restrained using a booster seat with the vehicle's lap and shoulder seat belt. Injury severity, frequency, and patterns of distribution were compared. Unrestrained children experienced moderate to severe injuries 3.8 to 19 times more frequently than children using restraints. There were more injuries to the head and face in unrestrained versus restrained children, but the head and face was the most frequently injured region for all groups. There were no serious cervical spine injuries reported for any group. Lower extremity fractures were not observed in booster seat users but occurred at similar rates in both unrestrained and seat belt restrained children. These fractures occurred in older children who were involved in more severe crashes. Unrestrained children were more likely to experience moderate and severe injuries than restrained children. The data sample suggests that booster use may reduce the risk of extremity fracture, as there were no extremity fractures in children restrained with booster seats. This work provides evidence for the efficacy of booster use for preventing orthopaedic injury in children. This evidence can be used to inform parents and establish recommendations for best practices in transporting children.
A kinetic energy model of two-vehicle crash injury severity.
Sobhani, Amir; Young, William; Logan, David; Bahrololoom, Sareh
2011-05-01
An important part of any model of vehicle crashes is the development of a procedure to estimate crash injury severity. After reviewing existing models of crash severity, this paper outlines the development of a modelling approach aimed at measuring the injury severity of people in two-vehicle road crashes. This model can be incorporated into a discrete event traffic simulation model, using simulation model outputs as its input. The model can then serve as an integral part of a simulation model estimating the crash potential of components of the traffic system. The model is developed using Newtonian Mechanics and Generalised Linear Regression. The factors contributing to the speed change (ΔV(s)) of a subject vehicle are identified using the law of conservation of momentum. A Log-Gamma regression model is fitted to measure speed change (ΔV(s)) of the subject vehicle based on the identified crash characteristics. The kinetic energy applied to the subject vehicle is calculated by the model, which in turn uses a Log-Gamma Regression Model to estimate the Injury Severity Score of the crash from the calculated kinetic energy, crash impact type, presence of airbag and/or seat belt and occupant age. Copyright © 2010 Elsevier Ltd. All rights reserved.
Statistical analysis of the national crash severity study data
DOT National Transportation Integrated Search
1980-08-01
This is the Final Report on a two-year statistical analysis of the data collected in the National Crash Severity Study (NCSS). The analysis presented is primarily concerned with the relationship between occupant injury severity and the crash conditio...
Taxonomy of Older Driver Behaviors and Crash Risk : with Appendices A and B
DOT National Transportation Integrated Search
2012-02-01
This projects objectives were to identify risky behaviors, driving habits, and exposure patterns that have been shown to increase the likelihood of crash involvement among older drivers; and to classify these crash-contributing factors according t...
An Analysis of fatal traffic crashes in Kentucky and recommended countermeasures.
DOT National Transportation Integrated Search
2005-11-01
The objective of this study were analyze fatal traffic crashes in Kentucky to identify patterns and causes of these crashes and to recommend potential countermeasures. The study included the following areas of analysis: 1) trends in fatal collisions,...
NASA Astrophysics Data System (ADS)
Sornette, D.
2003-04-01
This review presents a general theory of financial crashes and of stock market instabilities that his co-workers and the author have developed over the past seven years. We start by discussing the limitation of standard analyses for characterizing how crashes are special. The study of the frequency distribution of drawdowns, or runs of successive losses shows that large financial crashes are “outliers”: they form a class of their own as can be seen from their statistical signatures. If large financial crashes are “outliers”, they are special and thus require a special explanation, a specific model, a theory of their own. In addition, their special properties may perhaps be used for their prediction. The main mechanisms leading to positive feedbacks, i.e., self-reinforcement, such as imitative behavior and herding between investors are reviewed with many references provided to the relevant literature outside the narrow confine of Physics. Positive feedbacks provide the fuel for the development of speculative bubbles, preparing the instability for a major crash. We demonstrate several detailed mathematical models of speculative bubbles and crashes. A first model posits that the crash hazard drives the market price. The crash hazard may sky-rocket at some times due to the collective behavior of “noise traders”, those who act on little information, even if they think they “know”. A second version inverses the logic and posits that prices drive the crash hazard. Prices may skyrocket at some times again due to the speculative or imitative behavior of investors. According the rational expectation model, this entails automatically a corresponding increase of the probability for a crash. We also review two other models including the competition between imitation and contrarian behavior and between value investors and technical analysts. The most important message is the discovery of robust and universal signatures of the approach to crashes. These precursory patterns have been documented for essentially all crashes on developed as well as emergent stock markets, on currency markets, on company stocks, and so on. We review this discovery at length and demonstrate how to use this insight and the detailed predictions obtained from these models to forecast crashes. For this, we review the major crashes of the past that occurred on the major stock markets of the planet and describe the empirical evidence of the universal nature of the critical log-periodic precursory signature of crashes. The concept of an “anti-bubble” is also summarized, with the Japanese collapse from the beginning of 1991 to present, taken as a prominent example. A prediction issued and advertised in January 1999 has been until recently born out with remarkable precision, predicting correctly several changes of trends, a feat notoriously difficult using standard techniques of economic forecasting. We also summarize a very recent analysis the behavior of the U.S. S&P500 index from 1996 to August 2002 and the forecast for the two following years. We conclude by presenting our view of the organization of financial markets.
Using data mining techniques to predict the severity of bicycle crashes.
Prati, Gabriele; Pietrantoni, Luca; Fraboni, Federico
2017-04-01
To investigate the factors predicting severity of bicycle crashes in Italy, we used an observational study of official statistics. We applied two of the most widely used data mining techniques, CHAID decision tree technique and Bayesian network analysis. We used data provided by the Italian National Institute of Statistics on road crashes that occurred on the Italian road network during the period ranging from 2011 to 2013. In the present study, the dataset contains information about road crashes occurred on the Italian road network during the period ranging from 2011 to 2013. We extracted 49,621 road accidents where at least one cyclist was injured or killed from the original database that comprised a total of 575,093 road accidents. CHAID decision tree technique was employed to establish the relationship between severity of bicycle crashes and factors related to crash characteristics (type of collision and opponent vehicle), infrastructure characteristics (type of carriageway, road type, road signage, pavement type, and type of road segment), cyclists (gender and age), and environmental factors (time of the day, day of the week, month, pavement condition, and weather). CHAID analysis revealed that the most important predictors were, in decreasing order of importance, road type (0.30), crash type (0.24), age of cyclist (0.19), road signage (0.08), gender of cyclist (0.07), type of opponent vehicle (0.05), month (0.04), and type of road segment (0.02). These eight most important predictors of the severity of bicycle crashes were included as predictors of the target (i.e., severity of bicycle crashes) in Bayesian network analysis. Bayesian network analysis identified crash type (0.31), road type (0.19), and type of opponent vehicle (0.18) as the most important predictors of severity of bicycle crashes. Copyright © 2017 Elsevier Ltd. All rights reserved.
Truck crash severity in New York city: An investigation of the spatial and the time of day effects.
Zou, Wei; Wang, Xiaokun; Zhang, Dapeng
2017-02-01
This paper investigates the differences between single-vehicle and multi-vehicle truck crashes in New York City. The random parameter models take into account the time of day effect, the heterogeneous truck weight effect and other influencing factors such as crash characteristics, driver and vehicle characteristics, built environment factors and traffic volume attributes. Based on the results from the co-location quotient analysis, a spatial generalized ordered probit model is further developed to investigate the potential spatial dependency among single-vehicle truck crashes. The sample is drawn from the state maintained incident data, the publicly available Smart Location Data, and the BEST Practices Model (BPM) data from 2008 to 2012. The result shows that there exists a substantial difference between factors influencing single-vehicle and multi-vehicle truck crash severity. It also suggests that heterogeneity does exist in the truck weight, and it behaves differently in single-vehicle and multi-vehicle truck crashes. Furthermore, individual truck crashes are proved to be spatially dependent events for both single and multi-vehicle crashes. Last but not least, significant time of day effects were found for PM and night time slots, crashes that occurred in the afternoons and at nights were less severe in single-vehicle crashes, but more severe in multi-vehicle crashes. Copyright © 2016. Published by Elsevier Ltd.
DOT National Transportation Integrated Search
2009-04-28
Severe injury involvements on arterial roads account for a quarter of the total severe injuries reported statewide. Crash severity analysis was conducted and consisted of six road entity models and twenty crash type models. The data preparation and s...
Spatial analysis of alcohol-related motor vehicle crash injuries in southeastern Michigan.
Meliker, Jaymie R; Maio, Ronald F; Zimmerman, Marc A; Kim, Hyungjin Myra; Smith, Sarah C; Wilson, Mark L
2004-11-01
Temporal, behavioral and social risk factors that affect injuries resulting from alcohol-related motor vehicle crashes have been characterized in previous research. Much less is known about spatial patterns and environmental associations of alcohol-related motor vehicle crashes. The aim of this study was to evaluate geographic patterns of alcohol-related motor vehicle crashes and to determine if locations of alcohol outlets are associated with those crashes. In addition, we sought to demonstrate the value of integrating spatial and traditional statistical techniques in the analysis of this preventable public health risk. The study design was a cross-sectional analysis of individual-level blood alcohol content, traffic report information, census block group data, and alcohol distribution outlets. Besag and Newell's spatial analysis and traditional logistic regression both indicated that areas of low population density had more alcohol-related motor vehicle crashes than expected (P < 0.05). There was no significant association between alcohol outlets and alcohol-related motor vehicle crashes using distance analyses, logistic regression, and Chi-square. Differences in environmental or behavioral factors characteristic of areas of low population density may be responsible for the higher proportion of alcohol-related crashes occurring in these areas.
Investigation of factors associated with truck crash severity in Nebraska.
DOT National Transportation Integrated Search
2012-06-01
The severity of truck crashes is a concern in the state of Nebraska. This study was undertaken to investigate factors : associated with the severity of truck crashes. A two-year dataset obtained from the Nebraska Department of Roads : (NDOR) was anal...
Albertsson, Pontus; Falkmer, Torbjörn
2005-03-01
In order to identify and describe a pattern in bus and coach incident related injuries and fatalities, and to suggest possible future measures for improvement of bus and coach safety, a literature analysis was performed. The results formed a multi-faceted pattern, which briefly can be described as follows; women travelled more frequently by bus as compared to men. Injuries sustained predominantly affected women 60 years of age and older. Of all traffic fatalities in Europe, bus and coach fatalities represented 0.3-0.5%. In the OECD countries, the risk of being killed or seriously injured was found to be seven to nine times lower for bus and coach occupants as compared to those of car occupants. Despite the fact that fatalities were more frequent on rural roads, a vast majority of all bus and coach casualties occurred on urban roads and in dry weather conditions. Boarding and alighting caused about one-third of all injury cases. Collisions were a major injury-contributing factor. Buses and coaches most frequently collided with cars, but unprotected road users were hit in about one-third of all cases of a collision, the point of impact on the bus or the coach being typically frontal or side. Rollovers occurred in almost all cases of severe coach crashes. In this type of crash projection, total ejection, partial ejection, intrusion and smoke inhalation were the main injury mechanisms and among those, ejection being the most dangerous. A 2-point belt may prevent passenger ejection, but in frontal crashes when the upper abdominal parts and the head hit the seatback in front, it could, however, contribute to head and thoracic injuries. Hence, a 3-point belt provides the best restraint in rollovers and frontal crashes.
Wrong-way driving crashes: A random-parameters ordered probit analysis of injury severity.
Jalayer, Mohammad; Shabanpour, Ramin; Pour-Rouholamin, Mahdi; Golshani, Nima; Zhou, Huaguo
2018-04-23
In the context of traffic safety, whenever a motorized road user moves against the proper flow of vehicle movement on physically divided highways or access ramps, this is referred to as wrong-way driving (WWD). WWD is notorious for its severity rather than frequency. Based on data from the U.S. National Highway Traffic Safety Administration, an average of 355 deaths occur in the U.S. each year due to WWD. This total translates to 1.34 fatalities per fatal WWD crashes, whereas the same rate for other crash types is 1.10. Given these sobering statistics, WWD crashes, and specifically their severity, must be meticulously analyzed using the appropriate tools to develop sound and effective countermeasures. The objectives of this study were to use a random-parameters ordered probit model to determine the features that best describe WWD crashes and to evaluate the severity of injuries in WWD crashes. This approach takes into account unobserved effects that may be associated with roadway, environmental, vehicle, crash, and driver characteristics. To that end and given the rareness of WWD events, 15 years of crash data from the states of Alabama and Illinois were obtained and compiled. Based on this data, a series of contributing factors including responsible driver characteristics, temporal variables, vehicle characteristics, and crash variables are determined, and their impacts on the severity of injuries are explored. An elasticity analysis was also performed to accurately quantify the effect of significant variables on injury severity outcomes. According to the obtained results, factors such as driver age, driver condition, roadway surface conditions, and lighting conditions significantly contribute to the injury severity of WWD crashes. Copyright © 2018 Elsevier Ltd. All rights reserved.
Commercial truck crash injury severity analysis using gradient boosting data mining model.
Zheng, Zijian; Lu, Pan; Lantz, Brenda
2018-06-01
Truck crashes contribute to a large number of injuries and fatalities. This study seeks to identify the contributing factors affecting truck crash severity using 2010 to 2016 North Dakota and Colorado crash data provided by the Federal Motor Carrier Safety Administration. To fulfill a gap of previous studies, broad considerations of company and driver characteristics, such as company size and driver's license class, along with vehicle types and crash characteristics are researched. Gradient boosting, a data mining technique, is applied to comprehensively analyze the relationship between crash severities and a set of heterogeneous risk factors. Twenty five variables were tested and 22 of them are identified as significant variables contributing to injury severities, however, top 11 variables account for more than 80% of injury forecasting. The relative variable importance analysis is conducted and furthermore marginal effects of all contributing factors are also illustrated in this research. Several factors such as trucking company attributes (e.g., company size), safety inspection values, trucking company commerce status (e.g., interstate or intrastate), time of day, driver's age, first harmful events, and registration condition are found to be significantly associated with crash injury severity. Even though most of the identified contributing factors are significant for all four levels of crash severity, their relative importance and marginal effect are all different. For the first time, trucking company and driver characteristics are proved to have significant impact on truck crash injury severity. Some of the results in this study reinforce previous studies' conclusions. Findings in this study can be helpful for transportation agencies to reduce injury severity, and develop efficient strategies to improve safety. Copyright © 2018 National Safety Council and Elsevier Ltd. All rights reserved.
Spinal injury in car crashes: crash factors and the effects of occupant age.
Bilston, Lynne E; Clarke, Elizabeth C; Brown, Julie
2011-08-01
Motor vehicle crashes are the leading cause of serious spinal injury in most developed nations. However, since these injuries are rare, systematic analyses of the crash factors that are predictive of spinal injury have rarely been performed. This study aimed to use a population-reference crash sample to identify crash factors associated with moderate to severe spinal injury, and how these vary with occupant age. The US National Automotive Sampling System Crashworthiness Data System (NASS) data for 1993-2007 were analysed using logistic regression to identify crash factors associated with Abbreviated Injury Scale (AIS)2+ spinal injury among restrained vehicle passengers. Risk of moderate or severe spinal injury (AIS2+) was associated with higher severity crashes (OR=3.5 (95% CI 2.6 to 4.6)), intrusion into an occupant's seating position (OR=2.7 (95% CI 1.9 to 3.7)), striking a fixed object rather than another car (OR=1.7 (95% CI 1.3 to 2.1)), and use of a shoulder-only belt (OR=2.7 (95% CI 1.5 to 4.8)). Older occupants (65 years or older) were at higher risk of spinal injury than younger adults in frontal, side and rollover crashes. Children under 16 were at a lower risk of spinal injury than adults in all crash types except frontal crashes. While the risk of serious spinal injury in motor vehicle crashes is low, these injuries are more common in crashes of higher severity or into fixed objects, and in the presence of intrusion. There are elevated risks of spinal injury for older occupants compared with younger adults, which may reflect changes in biomechanical tolerances with age. Children appear to be at lower risk of serious spinal injury than adults except in frontal crashes.
Chen, Huiqin; Chen, Qiang; Chen, Lei; Zhang, Guanjun
2016-11-16
The objective of this research was to study risk factors that significantly influence the severity of crashes for drivers both under and not under the influence of alcohol. Ordinal logistic regression was applied to analyze a crash data set involving drivers under and not under the influence of alcohol in China from January 2011 to December 2014. Four risk factors were found to be significantly associated with the severity of driver injury, including crash partner and intersection type. Age group was found to be significantly associated with the severity of crashes involving drivers under the influence of alcohol. Crash partner, intersection type, lighting conditions, gender, and time of day were found to be significantly associated with severe driver injuries, the last of which was also significantly associated with severe crashes involving drivers not under the influence of alcohol. This study found that pedestrian involvement decreases the odds of severe driver injury when a driver is under the influence of alcohol, with a relative risk of 0.05 compared to the vehicle-to-vehicle group. The odds of severe driver injury at T-intersections were higher than those for traveling along straight roads. Age was shown to be an important factor, with drivers 50-60 years of age having higher odds of being involved in severe crashes compared to 20- to 30-year-olds when the driver was under the influence of alcohol. When the driver was not under the influence of alcohol, drivers suffered more severe injuries between midnight and early morning compared to early nighttime. The vehicle-to-motorcycle and vehicle-to-pedestrian groups experienced less severe driver injuries, and vehicle collisions with fixed objects exhibited higher odds of severe driver injury than did vehicle-to-vehicle impacts. The odds of severe driver injury at cross intersections were 0.29 compared to travel along straight roads. The odds of severe driver injury when street lighting was not available at night were 3.20 compared to daylight. The study indicated that female drivers are more likely to experience severe injury than male drivers when not under the influence of alcohol. Crashes between midnight and early morning exhibited higher odds of severe injury compared to those occurring at other times of day. The identification of risk factors and a discussion on the odds ratio between levels of the impact of the driver injury and crash severity may benefit road safety stakeholders when developing initiatives to reduce the severity of crashes.
Analysis of passenger-car crash injury severity in different work zone configurations.
Osman, Mohamed; Paleti, Rajesh; Mishra, Sabyasachee
2018-02-01
Work zone safety remains a priority to the Federal Highway Administration, State Highway Departments, highway engineers, and the traveling public. Work zones create a hospitable environment for crashes; an issue that gained tremendous share of attention in recent years. Therefore, every effort should be sought out to reduce the injury severity of crashes in work zones. In this paper we attempt to investigate factors contributing to the injury severity of passenger-car crashes in different work zone configurations. Considering the discrete ordinal nature of injury severity categories, a Mixed Generalized Ordered Response Probit (MGORP) modeling framework was developed. The model estimation was undertaken by compiling a database consisting of 10 years of crashes that involved at least one passenger car, and occurred in a work zone. Revealing the underlying factors contributing to injury severity levels for different work zone configurations will allow for distinguishing mitigation methods for higher severity outcomes that best suit each of the depicted work zone layouts. This can be accomplished through the implementation of specific safety measures based on the specific configuration of a work zone as a potential crash location. Elasticity analysis suggests that partial control of access, roadways classified as rural, crashes during evening times, crashes during weekends, and curved roadways are key factors that increase the likelihood of severe outcomes. Also, the effects of several covariates were found to vary across the different work zone configurations. Copyright © 2017 Elsevier Ltd. All rights reserved.
Sebego, Miriam; Naumann, Rebecca B.; Rudd, Rose A.; Voetsch, Karen; Dellinger, Ann M.; Ndlovu, Christopher
2015-01-01
In Botswana, increased development and motorization have brought increased road traffic-related death rates. Between 1981 and 2001, the road traffic-related death rate in Botswana more than tripled. The country has taken several steps over the last several years to address the growing burden of road traffic crashes and particularly to address the burden of alcohol-related crashes. This study examines the impact of the implementation of alcohol and road safety-related policies on crash rates, including overall crash rates, fatal crash rates, and single-vehicle nighttime fatal (SVNF) crash rates, in Botswana from 2004 to 2011. The overall crash rate declined significantly in June 2009 and June 2010, such that the overall crash rate from June 2010 to December 2011 was 22% lower than the overall crash rate from January 2004 to May 2009. Additionally, there were significant declines in average fatal crash and SVNF crash rates in early 2010. Botswana’s recent crash rate reductions occurred during a time when aggressive policies and other activities (e.g., education, enforcement) were implemented to reduce alcohol consumption and improve road safety. While it is unclear which of the policies or activities contributed to these declines and to what extent, these reductions are likely the result of several, combined efforts. PMID:24686164
Sebego, Miriam; Naumann, Rebecca B; Rudd, Rose A; Voetsch, Karen; Dellinger, Ann M; Ndlovu, Christopher
2014-09-01
In Botswana, increased development and motorization have brought increased road traffic-related death rates. Between 1981 and 2001, the road traffic-related death rate in Botswana more than tripled. The country has taken several steps over the last several years to address the growing burden of road traffic crashes and particularly to address the burden of alcohol-related crashes. This study examines the impact of the implementation of alcohol and road safety-related policies on crash rates, including overall crash rates, fatal crash rates, and single-vehicle nighttime fatal (SVNF) crash rates, in Botswana from 2004 to 2011. The overall crash rate declined significantly in June 2009 and June 2010, such that the overall crash rate from June 2010 to December 2011 was 22% lower than the overall crash rate from January 2004 to May 2009. Additionally, there were significant declines in average fatal crash and SVNF crash rates in early 2010. Botswana's recent crash rate reductions occurred during a time when aggressive policies and other activities (e.g., education, enforcement) were implemented to reduce alcohol consumption and improve road safety. While it is unclear which of the policies or activities contributed to these declines and to what extent, these reductions are likely the result of several, combined efforts. Copyright © 2014 Elsevier Ltd. All rights reserved.
A Heckman selection model for the safety analysis of signalized intersections
Wong, S. C.; Zhu, Feng; Pei, Xin; Huang, Helai; Liu, Youjun
2017-01-01
Purpose The objective of this paper is to provide a new method for estimating crash rate and severity simultaneously. Methods This study explores a Heckman selection model of the crash rate and severity simultaneously at different levels and a two-step procedure is used to investigate the crash rate and severity levels. The first step uses a probit regression model to determine the sample selection process, and the second step develops a multiple regression model to simultaneously evaluate the crash rate and severity for slight injury/kill or serious injury (KSI), respectively. The model uses 555 observations from 262 signalized intersections in the Hong Kong metropolitan area, integrated with information on the traffic flow, geometric road design, road environment, traffic control and any crashes that occurred during two years. Results The results of the proposed two-step Heckman selection model illustrate the necessity of different crash rates for different crash severity levels. Conclusions A comparison with the existing approaches suggests that the Heckman selection model offers an efficient and convenient alternative method for evaluating the safety performance at signalized intersections. PMID:28732050
Influence of pedestrian age and gender on spatial and temporal distribution of pedestrian crashes.
Toran Pour, Alireza; Moridpour, Sara; Tay, Richard; Rajabifard, Abbas
2018-01-02
Every year, about 1.24 million people are killed in traffic crashes worldwide and more than 22% of these deaths are pedestrians. Therefore, pedestrian safety has become a significant traffic safety issue worldwide. In order to develop effective and targeted safety programs, the location- and time-specific influences on vehicle-pedestrian crashes must be assessed. The main purpose of this research is to explore the influence of pedestrian age and gender on the temporal and spatial distribution of vehicle-pedestrian crashes to identify the hotspots and hot times. Data for all vehicle-pedestrian crashes on public roadways in the Melbourne metropolitan area from 2004 to 2013 are used in this research. Spatial autocorrelation is applied in examining the vehicle-pedestrian crashes in geographic information systems (GIS) to identify any dependency between time and location of these crashes. Spider plots and kernel density estimation (KDE) are then used to determine the temporal and spatial patterns of vehicle-pedestrian crashes for different age groups and genders. Temporal analysis shows that pedestrian age has a significant influence on the temporal distribution of vehicle-pedestrian crashes. Furthermore, men and women have different crash patterns. In addition, results of the spatial analysis shows that areas with high risk of vehicle-pedestrian crashes can vary during different times of the day for different age groups and genders. For example, for those between ages 18 and 65, most vehicle-pedestrian crashes occur in the central business district (CBD) during the day, but between 7:00 p.m. and 6:00 a.m., crashes among this age group occur mostly around hotels, clubs, and bars. This research reveals that temporal and spatial distributions of vehicle-pedestrian crashes vary for different pedestrian age groups and genders. Therefore, specific safety measures should be in place during high crash times at different locations for different age groups and genders to increase the effectiveness of the countermeasures in preventing and reducing vehicle-pedestrian crashes.
A spatial generalized ordered response model to examine highway crash injury severity.
Castro, Marisol; Paleti, Rajesh; Bhat, Chandra R
2013-03-01
This paper proposes a flexible econometric structure for injury severity analysis at the level of individual crashes that recognizes the ordinal nature of injury severity categories, allows unobserved heterogeneity in the effects of contributing factors, as well as accommodates spatial dependencies in the injury severity levels experienced in crashes that occur close to one another in space. The modeling framework is applied to analyze the injury severity sustained in crashes occurring on highway road segments in Austin, Texas. The sample is drawn from the Texas Department of Transportation (TxDOT) crash incident files from 2009 and includes a variety of crash characteristics, highway design attributes, driver and vehicle characteristics, and environmental factors. The results from our analysis underscore the value of our proposed model for data fit purposes as well as to accurately estimate variable effects. The most important determinants of injury severity on highways, according to our results, are (1) whether any vehicle occupant is ejected, (2) whether collision type is head-on, (3) whether any vehicle involved in the crash overturned, (4) whether any vehicle occupant is unrestrained by a seat-belt, and (5) whether a commercial truck is involved. Copyright © 2012 Elsevier Ltd. All rights reserved.
Schuliar, Yves; Chapenoire, Stéphane; Miras, Alain; Contrand, Benjamin; Lagarde, Emmanuel
2014-09-01
For investigation of air disasters, crash reconstruction is obtained using data from flight recorders, physical evidence from the site, and injuries patterns of the victims. This article describes a new software, Crash Injury Pattern Assessment Tool (CIPAT), to code and analyze injuries. The coding system was derived from the Abbreviated Injury Score (AIS). Scores were created corresponding to the amount of energy required causing the trauma (ER), and the software was developed to compute summary variables related to the position (assigned seat) of victims. A dataset was built from the postmortem examination of 154/228 victims of the Air France disaster (June 2009), recovered from the Atlantic Ocean after a complex and difficult task at a depth of 12790 ft. The use of CIPAT allowed to precise cause and circumstances of deaths and confirmed major dynamics parameters of the crash event established by the French Civil Aviation Safety Investigation Authority. © 2014 American Academy of Forensic Sciences.
Intersection crash prediction modeling with macro-level data from various geographic units.
Lee, Jaeyoung; Abdel-Aty, Mohamed; Cai, Qing
2017-05-01
There have been great efforts to develop traffic crash prediction models for various types of facilities. The crash models have played a key role to identify crash hotspots and evaluate safety countermeasures. In recent, many macro-level crash prediction models have been developed to incorporate highway safety considerations in the long-term transportation planning process. Although the numerous macro-level studies have found that a variety of demographic and socioeconomic zonal characteristics have substantial effects on traffic safety, few studies have attempted to coalesce micro-level with macro-level data from existing geographic units for estimating crash models. In this study, the authors have developed a series of intersection crash models for total, severe, pedestrian, and bicycle crashes with macro-level data for seven spatial units. The study revealed that the total, severe, and bicycle crash models with ZIP-code tabulation area data performs the best, and the pedestrian crash models with census tract-based data outperforms the competing models. Furthermore, it was uncovered that intersection crash models can be drastically improved by only including random-effects for macro-level entities. Besides, the intersection crash models are even further enhanced by including other macro-level variables. Lastly, the pedestrian and bicycle crash modeling results imply that several macro-level variables (e.g., population density, proportions of specific age group, commuters who walk, or commuters using bicycle, etc.) can be a good surrogate exposure for those crashes. Copyright © 2017 Elsevier Ltd. All rights reserved.
Planar Impacts in Rollover Crashes: Significance, Distribution and Injury Epidemiology
Bose, Dipan; Kerrigan, Jason R.; Foster, Jonathan B.; Crandall, Jeff R.; Tobaru, Shigeo
2011-01-01
While one third of all fatal motor vehicle crashes involve rollover of the vehicle, a substantially large portion of these rollover crashes involve planar impacts (e.g., frontal, side or rear impact) that influence the crash kinematics and subsequently the injury outcome. The objective of the study was to evaluate the distribution of planar impacts in rollover crashes, and in particular, to describe the differences in the underlying crash kinematics, injury severity and the regional distribution of injuries when compared to the rollover-dominated crashes without significant planar impact (i.e., primary rollovers). Sampled cases (n=6,900) from the U.S. National Automotive Sampling System – Crashworthiness Data System, representing approximately 3.3 million belted drivers involved in a rollover crash in years 1998–2008, were analyzed. Single vehicle rollover crashes with significant planar impact (21% of all rollover crashes) were in general more likely to result in occupant fatality and involved higher incidence of moderate to severe injuries compared to single vehicle primary rollovers (p<0.05). A substantial proportion of the planar impact rollovers ended in single quarter turn crashes (30%), mostly resulting from a frontal impact (59%). While chest was the most frequently injured body region among all rollover victims sustaining severe injuries, severe injuries sustained in primary rollovers were more isolated (single body region) in comparison to the ones sustained in rollovers with planar impacts. The results emphasize the higher risk of rollover victims sustaining an injury and the differences in distribution of injuries sustained when a planar impact is associated with the rollover crash. PMID:22105400
Comparing international crash statistics
DOT National Transportation Integrated Search
1999-12-01
In order to examine national developments in traffic safety, crash statistics from several of the more safety, crash statistics from several of the more United States. Data obtained from the Fatality Analysis Reporting System (FARS) and the Internati...
Dummy Measurement of Chest Injuries Induced by Two-Point Shoulder Belts
Augenstein, J.; Perdeck, E.; Bowen, J.; Stratton, J.; Horton, T.; Singer, M.; Digges, K.; Malliaris, A.; Steps, J.
2000-01-01
The University of Miami’s William Lehman Injury Research Center at the Jackson Memorial Medical Center conducts interdisciplinary investigations to study seriously injured restrained occupants in frontal automobile collisions. Engineering analysis of these crashes is conducted in conjunction with the National Crash Analysis Center at the George Washington University. The multidisciplinary research team includes expertise in crash investigation, crash reconstruction, computer graphics, biomechanics of injuries, crash data analysis, trauma care, and all of the medical specialties associated with the Ryder Trauma Center at Jackson Memorial Hospital. More than 350 injured occupants and their crashes have been studied in depth. The purpose of this paper is to report on an observed pattern of liver lacerations suffered by drivers wearing shoulder belts, without the lap belt fastened and to assess the ability of existing crash test dummies to measure the potential for these injuries. During the initial years of the study, 48 cases of drivers protected by shoulder belts but without the lap belt fastened met the criteria for the study. Fifty percent of these drivers suffered liver lacerations. Further study showed that 22 of the crashes involved damage to the right front of the vehicle. Among the drivers in vehicles with right front damage, 92% sustained injuries to the liver. This observation indicated that 2-point belts were most likely to produce liver injuries in low severity frontal collisions when the crash direction is 1 to 2 o’clock. An analysis of the National Accident Sampling System for the years 1988-95 indicated that liver injuries constitute about 0.5% of the injuries suffered by drivers who are in tow-away crashes. NASS data showed that the risk of chest injury is more likely among drivers with automatic shoulder belts than drivers with 3-point manual belts. The crash test dummies showed no difference in chest injury measures. Finite element computer modeling demonstrated that the high deflection of the right lower rib on the Hybrid III dummy predicts the liver injuries in the 1 o’clock crashes. These higher deflections were less apparent at the location of the center chest deflection measurement device on the Hybrid III. PMID:11558077
Dummy measurement of chest injuries induced by two-point shoulder belts.
Augenstein, J; Perdeck, E; Bowen, J; Stratton, J; Horton, T; Singer, M; Digges, K; Malliaris, A; Steps, J
2000-01-01
The University of Miami's William Lehman Injury Research Center at the Jackson Memorial Medical Center conducts interdisciplinary investigations to study seriously injured restrained occupants in frontal automobile collisions. Engineering analysis of these crashes is conducted in conjunction with the National Crash Analysis Center at the George Washington University. The multidisciplinary research team includes expertise in crash investigation, crash reconstruction, computer graphics, biomechanics of injuries, crash data analysis, trauma care, and all of the medical specialties associated with the Ryder Trauma Center at Jackson Memorial Hospital. More than 350 injured occupants and their crashes have been studied in depth. The purpose of this paper is to report on an observed pattern of liver lacerations suffered by drivers wearing shoulder belts, without the lap belt fastened and to assess the ability of existing crash test dummies to measure the potential for these injuries. During the initial years of the study, 48 cases of drivers protected by shoulder belts but without the lap belt fastened met the criteria for the study. Fifty percent of these drivers suffered liver lacerations. Further study showed that 22 of the crashes involved damage to the right front of the vehicle. Among the drivers in vehicles with right front damage, 92% sustained injuries to the liver. This observation indicated that 2-point belts were most likely to produce liver injuries in low severity frontal collisions when the crash direction is 1 to 2 o'clock. An analysis of the National Accident Sampling System for the years 1988-95 indicated that liver injuries constitute about 0.5% of the injuries suffered by drivers who are in tow-away crashes. NASS data showed that the risk of chest injury is more likely among drivers with automatic shoulder belts than drivers with 3-point manual belts. The crash test dummies showed no difference in chest injury measures. Finite element computer modeling demonstrated that the high deflection of the right lower rib on the Hybrid III dummy predicts the liver injuries in the 1 o'clock crashes. These higher deflections were less apparent at the location of the center chest deflection measurement device on the Hybrid III.
Brazilian Road Traffic Fatalities: A Spatial and Environmental Analysis
de Andrade, Luciano; Vissoci, João Ricardo Nickenig; Rodrigues, Clarissa Garcia; Finato, Karen; Carvalho, Elias; Pietrobon, Ricardo; de Souza, Eniuce Menezes; Nihei, Oscar Kenji; Lynch, Catherine; de Barros Carvalho, Maria Dalva
2014-01-01
Background Road traffic injuries (RTI) are a major public health epidemic killing thousands of people daily. Low and middle-income countries, such as Brazil, have the highest annual rates of road traffic fatalities. In order to improve road safety, this study mapped road traffic fatalities on a Brazilian highway to determine the main environmental factors affecting road traffic fatalities. Methods and Findings Four techniques were utilized to identify and analyze RTI hotspots. We used spatial analysis by points by applying kernel density estimator, and wavelet analysis to identify the main hot regions. Additionally, built environment analysis, and principal component analysis were conducted to verify patterns contributing to crash occurrence in the hotspots. Between 2007 and 2009, 379 crashes were notified, with 466 fatalities on BR277. Higher incidence of crashes occurred on sections of highway with double lanes (ratio 2∶1). The hotspot analysis demonstrated that both the eastern and western regions had higher incidences of crashes when compared to the central region. Through the built environment analysis, we have identified five different patterns, demonstrating that specific environmental characteristics are associated with different types of fatal crashes. Patterns 2 and 4 are constituted mainly by predominantly urban characteristics and have frequent fatal pedestrian crashes. Patterns 1, 3 and 5 display mainly rural characteristics and have higher prevalence of vehicular collisions. In the built environment analysis, the variables length of road in urban area, limited lighting, double lanes roadways, and less auxiliary lanes were associated with a higher incidence of fatal crashes. Conclusions By combining different techniques of analyses, we have identified numerous hotspots and environmental characteristics, which governmental or regulatory agencies could make use to plan strategies to reduce RTI and support life-saving policies. PMID:24498051
Koopmans, Joy M; Friedman, Lee; Kwon, Soyang; Sheehan, Karen
2015-04-01
Describe age-based urban pedestrian versus auto crash characteristics and identify crash characteristics associated with injury severity. Secondary analysis of the 2004-2010 National Highway and Traffic Safety Administration database for Illinois. All persons in Chicago crashes with age data who were listed as pedestrians (n=7175 child age ≤19 yo, n=16,398 adult age ≥20 yo) were included. Incidence and crash characteristics were analyzed by age groups and year. Main outcome measures were incidence, crash setting, and injury severity. Multivariate logistic regression analysis was performed to estimate injury severity by crash characteristics. Overall incidence was higher for child (146.6 per 100,000) versus adult (117.3 per 100,000) pedestrians but case fatality rate was lower (0.7% for children, 1.7% for adults). Child but not adult pedestrian injury incidence declined over time (trend test p<0.0001 for <5 yo, 5-9 yo, and 10-14 yo; p<0.05 for 15-19 yo, p=0.96 for ≥20 yo). Most crashes for both children and adults took place during optimal driving conditions. Injuries were more frequent during warmer months for younger age groups compared to older (χ(2)p<0.001). Midblock crashes increased as age decreased (p<0.0001 for trend). Most crashes occurred at sites with sub-optimal traffic controls but varied by age (p<0.0001 for trend). Crashes were more likely to be during daylight on dry roads in clear weather conditions for younger age groups compared to older (χ(2)p<0.001). Daylight was associated with less severe injury (child OR 0.93, 95% CI 0.87-0.98; adult OR 0.90, 95% CI 0.87-0.93). The incidence of urban pedestrian crashes declined over time for child subgroups but not for adults. The setting of pedestrian crashes in Chicago today varies by age but is similar to that seen in other urban locales previously. Injuries for all age groups tend to be less severe during daylight conditions. Age-based prevention efforts may prove beneficial. Copyright © 2015 Elsevier Ltd. All rights reserved.
Crash energy absorption of two-segment crash box with holes under frontal load
NASA Astrophysics Data System (ADS)
Choiron, Moch. Agus; Sudjito, Hidayati, Nafisah Arina
2016-03-01
Crash box is one of the passive safety components which designed as an impact energy absorber during collision. Crash box designs have been developed in order to obtain the optimum crashworthiness performance. Circular cross section was first investigated with one segment design, it rather influenced by its length which is being sensitive to the buckling occurrence. In this study, the two-segment crash box design with additional holes is investigated and deformation behavior and crash energy absorption are observed. The crash box modelling is performed by finite element analysis. The crash test components were impactor, crash box, and fixed rigid base. Impactor and the fixed base material are modelled as a rigid, and crash box material as bilinear isotropic hardening. Crash box length of 100 mm and frontal crash velocity of 16 km/jam are selected. Crash box material of Aluminum Alloy is used. Based on simulation results, it can be shown that holes configuration with 2 holes and ¾ length locations have the largest crash energy absorption. This condition associated with deformation pattern, this crash box model produces axisymmetric mode than other models.
Analyses of rear-end crashes based on classification tree models.
Yan, Xuedong; Radwan, Essam
2006-09-01
Signalized intersections are accident-prone areas especially for rear-end crashes due to the fact that the diversity of the braking behaviors of drivers increases during the signal change. The objective of this article is to improve knowledge of the relationship between rear-end crashes occurring at signalized intersections and a series of potential traffic risk factors classified by driver characteristics, environments, and vehicle types. Based on the 2001 Florida crash database, the classification tree method and Quasi-induced exposure concept were used to perform the statistical analysis. Two binary classification tree models were developed in this study. One was used for the crash comparison between rear-end and non-rear-end to identify those specific trends of the rear-end crashes. The other was constructed for the comparison between striking vehicles/drivers (at-fault) and struck vehicles/drivers (not-at-fault) to find more complex crash pattern associated with the traffic attributes of driver, vehicle, and environment. The modeling results showed that the rear-end crashes are over-presented in the higher speed limits (45-55 mph); the rear-end crash propensity for daytime is apparently larger than nighttime; and the reduction of braking capacity due to wet and slippery road surface conditions would definitely contribute to rear-end crashes, especially at intersections with higher speed limits. The tree model segmented drivers into four homogeneous age groups: < 21 years, 21-31 years, 32-75 years, and > 75 years. The youngest driver group shows the largest crash propensity; in the 21-31 age group, the male drivers are over-involved in rear-end crashes under adverse weather conditions and the 32-75 years drivers driving large size vehicles have a larger crash propensity compared to those driving passenger vehicles. Combined with the quasi-induced exposure concept, the classification tree method is a proper statistical tool for traffic-safety analysis to investigate crash propensity. Compared to the logistic regression models, tree models have advantages for handling continuous independent variables and easily explaining the complex interaction effect with more than two independent variables. This research recommended that at signalized intersections with higher speed limits, reducing the speed limit to 40 mph efficiently contribute to a lower accident rate. Drivers involved in alcohol use may increase not only rear-end crash risk but also the driver injury severity. Education and enforcement countermeasures should focus on the driver group younger than 21 years. Further studies are suggested to compare crash risk distributions of the driver age for other main crash types to seek corresponding traffic countermeasures.
The interactive effect on injury severity of driver-vehicle units in two-vehicle crashes.
Zeng, Qiang; Wen, Huiying; Huang, Helai
2016-12-01
This study sets out to investigate the interactive effect on injury severity of driver-vehicle units in two-vehicle crashes. A Bayesian hierarchical ordered logit model is proposed to relate the variation and correlation of injury severity of drivers involved in two-vehicle crashes to the factors of both driver-vehicle units and the crash configurations. A total of 6417 crash records with 12,834 vehicles involved in Florida are used for model calibration. The results show that older, female and not-at-fault drivers and those without use of safety equipment are more likely to be injured but less likely to injure the drivers in the other vehicles. New vehicles and lower speed ratios are associated with lower injury degree of both drivers involved. Compared with automobiles, vans, pick-ups, light trucks, median trucks, and heavy trucks possess better self-protection and stronger aggressivity. The points of impact closer to the driver's seat in general indicate a higher risk to the own drivers while engine cover and vehicle rear are the least hazardous to other drivers. Head-on crashes are significantly more severe than angle and rear-end crashes. We found that more severe crashes occurred on roadways than on shoulders or safety zones. Based on these results, some suggestions for traffic safety education, enforcement and engineering are made. Moreover, significant within-crash correlation is found in the crash data, which demonstrates the applicability of the proposed model. Copyright © 2016 Elsevier Ltd and National Safety Council. All rights reserved.
Changes in the Severity and Injury Sources of Thoracic Aorta Injuries due to Vehicular Crashes.
Ryb, Gabriel; Dischinger, Patricia; Kerns, Timothy; Burch, Cynthia; Rabin, Joseph; Ho, Shiu
Research using the National Automotive Sampling System-Crashworthiness Data System (NASS-CDS) suggested a decreased adjusted risk of thoracic aorta injuries (TAI) for newer vehicles during near-side crashes and an increased adjusted TAI risk during frontal crashes. This study attempted to explore possible explanations of these findings. Adult front seat occupants in the Crash Injury Research and Engineering Network (CIREN) database through June 2012 were studied. TAI cases were compared with remaining cases in relation to crash and vehicular characteristics. TAI cases of later crash year (CY) (2004-2012) were compared to those in earlier CY (1996-2003) in relation to TAI severity (minor, moderate, severe and non-survivable). TAI cases in newer model year (MY) vehicles (1999-2012) were compared to those in older vehicles (1988-98) in relation to injury source (steering wheel, front, left, seat belt, air bag and other or unknown). Analysis was stratified by direction of impact (frontal and near-side) and the use of restraints. The similar TAI severity of earlier and later CY among frontal crashes suggests that the observed changes in the adjusted odds of injury seen in NASS-CDS are not due to an increase in injury detection. The decrease in TAI severity among newer vehicles in near-side crashes of later CY is consistent with a beneficial effect of crashworthiness improvements for this crash configuration. A shift of injury source in frontal crashes from the steering wheel in older vehicles to "front of vehicle structures", "seat belts" and "unknown and other" in newer vehicles should suggest potential sites for crashworthiness improvements.
Mahajan, Narinder; Aggarwal, Meenu; Raina, Sunil; Verma, Lekh Raj; Mazta, Salig Ram; Gupta, B P
2013-07-01
What are the various injuries in road traffic crash cases? To study various non-fatal injuries in road traffic crash cases. Hospital based Descriptive study. The study population comprised of 401 consecutive cases of non- fatal injuries involved in road traffic crashes and reported at Indira Gandhi Medical College hospital, Shimla. 1(st) June 2005 to 31(st) May 2006. Demographic characteristics of the victims, pattern of injuries and hospital stay of the victims. Types of crashes, time, day and month of crashes, vehicles involved in crashes, use of protective gear etc. Percentages, Proportions. 73% of the injured victims were young between 20-49yrs, male to female ratio being 5.3:1. Employees (34.7%) and occupants of transport vehicles (45.9%) constituted the maximum number of the victims. Major injuries (fractures and abd. injuries) were reported in 53.4% of the victims and fractures of lower limb were the commonest of the injuries (26.3%). Use of seat-belt was found to be alarmingly low (14.3%) amongst the four- wheeler users and its non-use was found to be significantly associated with the major injuries. Helmet was used by 36 cases (66.7%) out of total of 54 users of motorized two-wheelers at the time of crash. Human error was the most reported cause of crash (82%) and the most common mode of crash was skidding and/rolling down (55%).23.1% of the drivers were reported to have consumed alcohol at the time of crash.
The role of intersection and street design on severity of bicycle-motor vehicle crashes
Verma, Santosh; Mekary, Rania A; Courtney, Theodore K; Christiani, David C
2017-01-01
Background Safety concerns are a major barrier to cycling. Intersection and street design variables such as intersection angles and street width might contribute to the severity of crashes and the safety concerns. In this study we examined whether these design variables were associated with bicycle-motor vehicle crashes (BMVC) severity. Methods Using the geographical information system and latitudes/longitudes recorded by the police using a global positioning device, we extracted intersection angles, street width, bicycle facilities, posted speed limits and annual average daily traffic from 3266 BMVC data from New York City police records. Additional variables about BMVC, including age and sex of the bicyclist, time of the day, road surface conditions, road character, vehicle type and injury severity, were obtained from police reports. Injury severity was classified as severe (incapacitating or killed) or non-severe (non-incapacitating, possible injury). The associations between injury severity and environment design variables were examined using multivariate log-binomial regression model. Findings Compared with crashes at orthogonal intersections, crashes at non-orthogonal intersections had 1.37 times (95% CI 1.05 to 1.80) and non-intersection street segments had 1.31 times (95% CI 1.01 to 1.70) higher risk of a severe injury. Crashes that involved a truck or a bus were twice as likely to result in a severe injury outcome; street width was not significantly associated with injury severity. Conclusion Crashes at non-orthogonal intersections and non-intersection segments are more likely to result in higher injury severity. The findings can be used to improve road design and develop effective safety interventions. PMID:27881469
Jafari Anarkooli, A; Hadji Hosseinlou, M
2016-02-01
Many studies have examined different factors contributing to the injury severity of crashes; however, relatively few studies have focused on the crashes by considering the specific effects of lighting conditions. This research investigates lighting condition differences in the injury severity of crashes using 3-year (2009-2011) crash data of two-lane rural roads of the state of Washington. Separate ordered-probit models were developed to predict the effects of a set of factors expected to influence injury severity in three lighting conditions; daylight, dark, and dark with street lights. A series of likelihood ratio tests were conducted to determine if these lighting condition models were justified. The modeling results suggest that injury severity in specific lighting conditions are associated with contributing factors in different ways, and that such differences cannot be uncovered by focusing merely on one aggregate model. Key differences include crash location, speed limit, shoulder width, driver action, and three collision types (head-on, rear-end, and right-side impact collisions). This paper highlights the importance of deploying street lights at and near intersections (or access points) on two-lane rural roads because injury severity highly increases when crashes occur at these points in dark conditions. Copyright © 2016 Elsevier Ltd and National Safety Council. All rights reserved.
Sutyak, J P; Passi, V; Hammond, J S
1997-09-01
Air bags (ABs) may be perceived by the public and physicians as protection for thoracoabdominal injuries. This study compares injury patterns when air bags are used alone with injury patterns when air bags plus mechanical restraints (MRs) are used. Patients treated over a 4-year period with emergency medical services-documented AB deployment alone (n = 16) or AB plus MR (n = 22) were identified by trauma registry query. Medical records were reviewed and injuries recorded. Air bag-alone users had more severe overall (injury severity score > or = 15:9 vs 5), chest (abbreviated injury score [AIS] > or = 3:5 vs 1), and abdominal injuries (AIS > or = 3:6 vs 0). They required more tube thoracostomies (5 vs 0) and laparotomies (6 vs 0), longer hospitalizations (11.9 +/- 3.2 vs 5.3 +/- 1.4 days), and more intensive care unit admissions (8 vs 1). Craniofacial injuries (AIS > or = 3:6 vs 6) and fractures were similar. More victims using air bags alone required impatient rehabilitation and some patients died (6 vs 1). Crash victims using air bags alone (vs AB plus MR) had increased injury severity, hospitalizations, thoracoabdominal procedures, and rehabilitation. Physicians must be aware of the incomplete protection by air bags alone.
Vehicle crashworthiness ratings in Australia.
Cameron, M; Mach, T; Neiger, D; Graham, A; Ramsay, R; Pappas, M; Haley, J
1994-08-01
The paper reviews the published vehicle safety ratings based on mass crash data from the United States, Sweden, and Great Britain. It then describes the development of vehicle crashworthiness ratings based on injury compensation claims and police accident reports from Victoria and New South Wales, the two most populous states in Australia. Crashworthiness was measured by a combination of injury severity (of injured drivers) and injury risk (of drivers involved in crashes). Injury severity was based on 22,600 drivers injured in crashes in the two states. Injury risk was based on 70,900 drivers in New South Wales involved in crashes after which a vehicle was towed away. Injury risk measured in this way was compared with the "relative injury risk" of particular model cars involved in two car crashes in Victoria (where essentially only casualty crashes are reported), which was based on the method developed by Folksam Insurance in Sweden from Evans' double-pair comparison method. The results include crashworthiness ratings for the makes and models crashing in Australia in sufficient numbers to measure their crash performance adequately. The ratings were normalised for the driver sex and speed limit at the crash location, the two factors found to be strongly related to injury risk and/or severity and to vary substantially across makes and models of Australian crash-involved cars. This allows differences in crashworthiness of individual models to be seen, uncontaminated by major crash exposure differences.
Crash countermeasure and mobility effects.
DOT National Transportation Integrated Search
2012-04-19
The Michigan Department of Transportation (MDOT) has undertaken several initiatives to reduce crashes on its roadway network. In 2009, there were 2,201 reported crashes involving pedestrians and 866 reported crashes involving bicyclists in Michigan. ...
Changes in the Severity and Injury Sources of Thoracic Aorta Injuries due to Vehicular Crashes
Ryb, Gabriel; Dischinger, Patricia; Kerns, Timothy; Burch, Cynthia; Rabin, Joseph; Ho, Shiu
2013-01-01
Research using the National Automotive Sampling System-Crashworthiness Data System (NASS-CDS) suggested a decreased adjusted risk of thoracic aorta injuries (TAI) for newer vehicles during near-side crashes and an increased adjusted TAI risk during frontal crashes. This study attempted to explore possible explanations of these findings. Adult front seat occupants in the Crash Injury Research and Engineering Network (CIREN) database through June 2012 were studied. TAI cases were compared with remaining cases in relation to crash and vehicular characteristics. TAI cases of later crash year (CY) (2004–2012) were compared to those in earlier CY (1996–2003) in relation to TAI severity (minor, moderate, severe and non-survivable). TAI cases in newer model year (MY) vehicles (1999–2012) were compared to those in older vehicles (1988–98) in relation to injury source (steering wheel, front, left, seat belt, air bag and other or unknown). Analysis was stratified by direction of impact (frontal and near-side) and the use of restraints. The similar TAI severity of earlier and later CY among frontal crashes suggests that the observed changes in the adjusted odds of injury seen in NASS-CDS are not due to an increase in injury detection. The decrease in TAI severity among newer vehicles in near-side crashes of later CY is consistent with a beneficial effect of crashworthiness improvements for this crash configuration. A shift of injury source in frontal crashes from the steering wheel in older vehicles to “front of vehicle structures”, “seat belts” and “unknown and other” in newer vehicles should suggest potential sites for crashworthiness improvements. PMID:24406956
Russo, Brendan J; Savolainen, Peter T
2018-08-01
Median-crossover crashes are among the most hazardous events that can occur on freeways, often resulting in severe or fatal injuries. The primary countermeasure to reduce the occurrence of such crashes is the installation of a median barrier. When installation of a median barrier is warranted, transportation agencies are faced with the decision among various alternatives including concrete barriers, beam guardrail, or high-tension cable barriers. Each barrier type differs in terms of its deflection characteristics upon impact, the required installation and maintenance costs, and the roadway characteristics (e.g., median width) where installation would be feasible. This study involved an investigation of barrier performance through an in-depth analysis of crash frequency and severity data from freeway segments where high-tension cable, thrie-beam, and concrete median barriers were installed. A comprehensive manual review of crash reports was conducted to identify crashes in which a vehicle left the roadway and encroached into the median. This review also involved an examination of crash outcomes when a barrier strike occurred, which included vehicle containment, penetration, or re-direction onto the travel lanes. The manual review of crash reports provided critical supplementary information through narratives and diagrams not normally available through standard fields on police crash report forms. Statistical models were estimated to identify factors that affect the frequency, severity, and outcomes of median-related crashes, with particular emphases on differences between segments with varying median barrier types. Several roadway-, traffic-, and environmental-related characteristics were found to affect these metrics, with results varying across the different barrier types. The results of this study provide transportation agencies with important guidance as to the in-service performance of various types of median barrier. Copyright © 2018 Elsevier Ltd. All rights reserved.
DOT National Transportation Integrated Search
1995-08-01
Regardless of whether we consider fatal crashes recorded throughout the United States or total crashes recorded in one state, it is clear that speeding is a serious threat to the motoring public. In 1993, for example, some 53,343 drivers were involve...
Analyzing and modeling risk exposure of pedestrian children to involvement in car crashes.
Elias, Wafa; Shiftan, Yoram
2014-01-01
This paper analyzes the various variables affecting pedestrian children road crashes, placing emphasis on the effect of daily activity patterns and the built environment, including the children's residential neighborhoods and the land use of the places where they conduct their activities. Two complementary data sources from the case study of an Arab town in northern Israel were used to provide a holistic picture of child-pedestrian road crashes: police files providing detailed analyzes of the reason for each crash, its location, and the characteristics of the driver involved; and a survey of 199 households with both involved and not involved children in road crashes, including a one-day travel diary. The study found that a combination of three groups of variables affects child-pedestrian road crashes: socio-economic status, travel patterns, and land use. Most vulnerable are boys from a low socio-economic group who live in areas of high density and mixed land use near a major road and who tend to walk to and from school and additional activities after school. Copyright © 2013 Elsevier Ltd. All rights reserved.
To brake or to accelerate? Safety effects of combined speed and red light cameras.
De Pauw, Ellen; Daniels, Stijn; Brijs, Tom; Hermans, Elke; Wets, Geert
2014-09-01
The present study evaluates the traffic safety effect of combined speed and red light cameras at 253 signalized intersections in Flanders, Belgium that were installed between 2002 and 2007. The adopted approach is a before-and-after study with control for the trend. The analyses showed a non-significant increase of 5% in the number of injury crashes. An almost significant decrease of 14% was found for the more severe crashes. The number of rear-end crashes turned out to have increased significantly (+44%), whereas a non-significant decrease (-6%) was found in the number of side crashes. The decrease for the severe crashes was mainly attributable to the effect on side crashes, for which a significant decrease of 24% was found. It is concluded that combined speed and red light cameras have a favorable effect on traffic safety, in particular on severe crashes. However, future research should examine the circumstances of rear-end crashes and how this increase can be managed. Copyright © 2014 National Safety Council and Elsevier Ltd. All rights reserved.
Crash energy absorption of two-segment crash box with holes under frontal load
DOE Office of Scientific and Technical Information (OSTI.GOV)
Choiron, Moch Agus, E-mail: agus-choiron@ub.ac.id; Sudjito,; Hidayati, Nafisah Arina
Crash box is one of the passive safety components which designed as an impact energy absorber during collision. Crash box designs have been developed in order to obtain the optimum crashworthiness performance. Circular cross section was first investigated with one segment design, it rather influenced by its length which is being sensitive to the buckling occurrence. In this study, the two-segment crash box design with additional holes is investigated and deformation behavior and crash energy absorption are observed. The crash box modelling is performed by finite element analysis. The crash test components were impactor, crash box, and fixed rigid base.more » Impactor and the fixed base material are modelled as a rigid, and crash box material as bilinear isotropic hardening. Crash box length of 100 mm and frontal crash velocity of 16 km/jam are selected. Crash box material of Aluminum Alloy is used. Based on simulation results, it can be shown that holes configuration with 2 holes and ¾ length locations have the largest crash energy absorption. This condition associated with deformation pattern, this crash box model produces axisymmetric mode than other models.« less
Safety performance evaluation of cable median barriers on freeways in Florida.
Alluri, Priyanka; Haleem, Kirolos; Gan, Albert; Mauthner, John
2016-07-03
This article aims to evaluate the safety performance of cable median barriers on freeways in Florida. The safety performance evaluation was based on the percentages of barrier and median crossovers by vehicle type, crash severity, and cable median barrier type (Trinity Cable Safety System [CASS] and Gibraltar system). Twenty-three locations with cable median barriers totaling about 101 miles were identified. Police reports of 6,524 crashes from years 2005-2010 at these locations were reviewed to verify and obtain detailed crash information. A total of 549 crashes were determined to be barrier related (i.e., crashes involving vehicles hitting the cable median barrier) and were reviewed in further detail to identify crossover crashes and the manner in which the vehicles crossed the barriers; that is, by either overriding, underriding, or penetrating the barriers. Overall, 2.6% of vehicles that hit the cable median barrier crossed the median and traversed into the opposite travel lane. Overall, 98.1% of cars and 95.5% of light trucks that hit the barrier were prevented from crossing the median. In other words, 1.9% of cars and 4.5% of light trucks that hit the barrier had crossed the median and encroached on the opposite travel lanes. There is no significant difference in the performance of cable median barrier for cars versus light trucks in terms of crossover crashes. In terms of severity, overrides were more severe compared to underrides and penetrations. The statistics showed that the CASS and Gibraltar systems performed similarly in terms of crossover crashes. However, the Gibraltar system experienced a higher proportion of penetrations compared to the CASS system. The CASS system resulted in a slightly higher percentage of moderate and minor injury crashes compared to the Gibraltar system. Cable median barriers are successful in preventing median crossover crashes; 97.4% of the cable median barrier crashes were prevented from crossing over the median. Of all of the vehicles that hit the barrier, 83.6% were either redirected or contained by the cable barrier system. Barrier crossover crashes were found to be more severe compared to barrier noncrossover crashes. In addition, overrides were found to be more severe compared to underrides and penetrations.
Wang, Chen; Lu, Linjun; Lu, Jian; Wang, Tao
2016-01-01
In order to improve motorcycle safety, this article examines the correlation between crash avoidance maneuvers and injury severity sustained by motorcyclists, under multiple precrash conditions. Ten-year crash data for single-vehicle motorcycle crashes from the General Estimates Systems (GES) were analyzed, using partial proportional odds models (i.e., generalized ordered logit models). The modeling results show that "braking (no lock-up)" is associated with a higher probability of increased severity, whereas "braking (lock-up)" is associated with a higher probability of decreased severity, under all precrash conditions. "Steering" is associated with a higher probability of reduced injury severity when other vehicles are encroaching, whereas it is correlated with high injury severity under other conditions. "Braking and steering" is significantly associated with a higher probability of low severity under "animal encounter and object presence," whereas it is surprisingly correlated with high injury severity when motorcycles are traveling off the edge of the road. The results also show that a large number of motorcyclists did not perform any crash avoidance maneuvers or conducted crash avoidance maneuvers that are significantly associated with high injury severity. In general, this study suggests that precrash maneuvers are an important factor associated with motorcyclists' injury severity. To improve motorcycle safety, training/educational programs should be considered to improve safety awareness and adjust driving habits of motorcyclists. Antilock brakes and such systems are also promising, because they could effectively prevent brake lock-up and assist motorcyclists in maneuvering during critical conditions. This study also provides valuable information for the design of motorcycle training curriculum.
Mahajan, Narinder; Aggarwal, Meenu; Raina, Sunil; Verma, Lekh Raj; Mazta, Salig Ram; Gupta, B P
2013-01-01
Research Question: What are the various injuries in road traffic crash cases? Objectives: To study various non-fatal injuries in road traffic crash cases. Study Design: Hospital based Descriptive study. Study Population: The study population comprised of 401 consecutive cases of non- fatal injuries involved in road traffic crashes and reported at Indira Gandhi Medical College hospital, Shimla. Study Period: 1st June 2005 to 31st May 2006. Study Variables: Demographic characteristics of the victims, pattern of injuries and hospital stay of the victims. Types of crashes, time, day and month of crashes, vehicles involved in crashes, use of protective gear etc. Statistical Analysis: Percentages, Proportions. Results: 73% of the injured victims were young between 20-49yrs, male to female ratio being 5.3:1. Employees (34.7%) and occupants of transport vehicles (45.9%) constituted the maximum number of the victims. Major injuries (fractures and abd. injuries) were reported in 53.4% of the victims and fractures of lower limb were the commonest of the injuries (26.3%). Use of seat-belt was found to be alarmingly low (14.3%) amongst the four- wheeler users and its non-use was found to be significantly associated with the major injuries. Helmet was used by 36 cases (66.7%) out of total of 54 users of motorized two-wheelers at the time of crash. Human error was the most reported cause of crash (82%) and the most common mode of crash was skidding and/rolling down (55%).23.1% of the drivers were reported to have consumed alcohol at the time of crash. PMID:24404456
2007 South Dakota motor vehicle traffic crash summary
DOT National Transportation Integrated Search
2008-01-01
The Motor Vehicle Traffic Crash Summary is divided into two main sections, Historical : Trends and 2007 Motor Vehicle Traffic Crash Profile. The Historical Trend section : provides information on alcohol involvement in motor vehicle crashes, severity...
2006 South Dakota motor vehicle traffic crash summary
DOT National Transportation Integrated Search
2007-05-01
The Motor Vehicle Traffic Crash Summary is divided into two main sections, Historical : Trends and 2006 Motor Vehicle Traffic Crash Profile. The Historical Trend section : provides information on alcohol involvement in motor vehicle crashes, severity...
2008 South Dakota motor vehicle traffic crash summary
DOT National Transportation Integrated Search
2009-06-01
The Motor Vehicle Traffic Crash Summary is divided into two main sections, Historical : Trends and 2008 Motor Vehicle Traffic Crash Profile. The Historical Trend section : provides information on alcohol involvement in motor vehicle crashes, severity...
2009 South Dakota motor vehicle traffic crash summary
DOT National Transportation Integrated Search
2010-06-01
The Motor Vehicle Traffic Crash Summary is divided into two main sections, Historical : Trends and 2009 Motor Vehicle Traffic Crash Profile. The Historical Trend section : provides information on alcohol involvement in motor vehicle crashes, severity...
Crash risk analysis during fog conditions using real-time traffic data.
Wu, Yina; Abdel-Aty, Mohamed; Lee, Jaeyoung
2018-05-01
This research investigates the changes of traffic characteristics and crash risks during fog conditions. Using real-time traffic flow and weather data at two regions in Florida, the traffic patterns at the fog duration were compared to the traffic patterns at the clear duration. It was found that the average 5-min speed and the average 5-min volume were prone to decreasing during fog. Based on previous studies, a "Crash Risk Increase Indicator (CRII)" was proposed to explore the differences of crash risk between fog and clear conditions. A binary logistic regression model was applied to link the increase of crash risks with traffic flow characteristics. The results suggested that the proposed indicator worked well in evaluating the increase of crash risk under fog condition. It was indicated that the crash risk was prone to increase at ramp vicinities in fog conditions. Also, the average 5-min volume during fog and the lane position are important factors for crash risk increase. The differences between the regions were also explored in this study. The results indicated that the locations with heavier traffic or locations at the lanes that were closest to the median in Region 2 were more likely to observe an increase in crash risks in fog conditions. It is expected that the proposed indicator can help identify the dangerous traffic status under fog conditions and then proper ITS technologies can be implemented to enhance traffic safety when the visibility declines. Copyright © 2017 Elsevier Ltd. All rights reserved.
The Stock Market Crashes of 1929 and 1987: Linking History and Personal Finance Education
ERIC Educational Resources Information Center
Lopus, Jane S.
2005-01-01
This article discusses two twentieth-century stock market crashes: the crash of 1929 and the crash of 1987. When this material is presented to students, they see important parallels between the two historical events. But despite remarkable similarities in the severity and many other aspects of the two crashes, the crash of 1929 was followed by the…
Human factors in aviation crashes involving older pilots.
Li, Guohua; Baker, Susan P; Lamb, Margaret W; Grabowski, Jurek G; Rebok, George W
2002-02-01
Pilot errors are recognized as a contributing factor in as many as 80% of aviation crashes. Experimental studies using flight simulators indicate that due to decreased working memory capacity, older pilots are outperformed by their younger counterparts in communication tasks and flight summary scores. This study examines age-related differences in crash circumstances and pilot errors in a sample of pilots who flew commuter aircraft or air taxis and who were involved in airplane or helicopter crashes. A historical cohort of 3306 pilots who in 1987 flew commuter aircraft or air taxis and were 45-54 yr of age was constructed using the Federal Aviation Administration's airmen information system. Crash records of the study subjects for the years 1983-1997 were obtained from the National Transportation Safety Board (NTSB) by matching name and date of birth. NTSB's investigation reports were reviewed to identify pilot errors and other contributing factors. Comparisons of crash circumstances and human factors were made between pilots aged 40-49 yr and pilots aged 50-63 yr. A total of 165 crash records were studied, with 52% of these crashes involving pilots aged 50-63 yr. Crash circumstances, such as time and location of crash, type and phase of flight, and weather conditions, were similar between the two age groups. Pilot error was a contributing factor in 73% of the crashes involving younger pilots and in 69% of the crashes involving older pilots (p = 0.50). Age-related differences in the pattern of pilot errors were statistically insignificant. Overall, 23% of pilot errors were attributable to inattentiveness, 20% to flawed decisions, 18% to mishandled aircraft kinetics, and 18% to mishandled wind/runway conditions. Neither crash circumstances nor the prevalence and patterns of pilot errors appear to change significantly as age increases from the 40s to the 50s and early 60s.
Saha, Dibakar; Alluri, Priyanka; Gan, Albert; Wu, Wanyang
2018-02-21
The objective of this study was to investigate the relationship between bicycle crash frequency and their contributing factors at the census block group level in Florida, USA. Crashes aggregated over the census block groups tend to be clustered (i.e., spatially dependent) rather than randomly distributed. To account for the effect of spatial dependence across the census block groups, the class of conditional autoregressive (CAR) models were employed within the hierarchical Bayesian framework. Based on four years (2011-2014) of crash data, total and fatal-and-severe injury bicycle crash frequencies were modeled as a function of a large number of variables representing demographic and socio-economic characteristics, roadway infrastructure and traffic characteristics, and bicycle activity characteristics. This study explored and compared the performance of two CAR models, namely the Besag's model and the Leroux's model, in crash prediction. The Besag's models, which differ from the Leroux's models by the structure of how spatial autocorrelation are specified in the models, were found to fit the data better. A 95% Bayesian credible interval was selected to identify the variables that had credible impact on bicycle crashes. A total of 21 variables were found to be credible in the total crash model, while 18 variables were found to be credible in the fatal-and-severe injury crash model. Population, daily vehicle miles traveled, age cohorts, household automobile ownership, density of urban roads by functional class, bicycle trip miles, and bicycle trip intensity had positive effects in both the total and fatal-and-severe crash models. Educational attainment variables, truck percentage, and density of rural roads by functional class were found to be negatively associated with both total and fatal-and-severe bicycle crash frequencies. Published by Elsevier Ltd.
Yuan, Quan; Lu, Meng; Theofilatos, Athanasios; Li, Yi-Bing
2017-02-01
Rear-end crashes attribute to a large portion of total crashes in China, which lead to many casualties and property damage, especially when involving commercial vehicles. This paper aims to investigate the critical factors for occupant injury severity in the specific rear-end crash type involving trucks as the front vehicle (FV). This paper investigated crashes occurred from 2011 to 2013 in Beijing area, China and selected 100 qualified cases i.e., rear-end crashes involving trucks as the FV. The crash data were supplemented with interviews from police officers and vehicle inspection. A binary logistic regression model was used to build the relationship between occupant injury severity and corresponding affecting factors. Moreover, a multinomial logistic model was used to predict the likelihood of fatal or severe injury or no injury in a rear-end crash. The results provided insights on the characteristics of driver, vehicle and environment, and the corresponding influences on the likelihood of a rear-end crash. The binary logistic model showed that drivers' age, weight difference between vehicles, visibility condition and lane number of road significantly increased the likelihood for severe injury of rear-end crash. The multinomial logistic model and the average direct pseudo-elasticity of variables showed that night time, weekdays, drivers from other provinces and passenger vehicles as rear vehicles significantly increased the likelihood of rear drivers being fatal. All the abovementioned significant factors should be improved, such as the conditions of lighting and the layout of lanes on roads. Two of the most common driver factors are drivers' age and drivers' original residence. Young drivers and outsiders have a higher injury severity. Therefore it is imperative to enhance the safety education and management on the young drivers who steer heavy duty truck from other cities to Beijing on weekdays. Copyright © 2016 Daping Hospital and the Research Institute of Surgery of the Third Military Medical University. Production and hosting by Elsevier B.V. All rights reserved.
Park, Juneyoung; Abdel-Aty, Mohamed; Lee, Jaeyoung
2016-09-01
Although many researchers have estimated the crash modification factors (CMFs) for specific treatments (or countermeasures), there is a lack of prior studies that have explored the variation of CMFs. Thus, the main objectives of this study are: (a) to estimate CMFs for the installation of different types of roadside barriers, and (b) to determine the changes of safety effects for different crash types, severities, and conditions. Two observational before-after analyses (i.e. empirical Bayes (EB) and full Bayes (FB) approaches) were utilized in this study to estimate CMFs. To consider the variation of safety effects based on different vehicle, driver, weather, and time of day information, the crashes were categorized based on vehicle size (passenger and heavy), driver age (young, middle, and old), weather condition (normal and rain), and time difference (day time and night time). The results show that the addition of roadside barriers is safety effective in reducing severe crashes for all types and run-off roadway (ROR) crashes. On the other hand, it was found that roadside barriers tend to increase all types of crashes for all severities. The results indicate that the treatment might increase the total number of crashes but it might be helpful in reducing injury and severe crashes. In this study, the variation of CMFs was determined for ROR crashes based on the different vehicle, driver, weather, and time information. Based on the findings from this study, the variation of CMFs can enhance the reliability of CMFs for different roadway conditions in decision making process. Also, it can be recommended to identify the safety effects of specific treatments for different crash types and severity levels with consideration of the different vehicle, driver, weather, and time of day information. Copyright © 2016 Elsevier Ltd and National Safety Council. All rights reserved.
The Pattern of Road Traffic Crashes in South East Iran
Rad, Mahdieh; Martiniuk, Alexandra LC.; Ansari-Moghaddam, Alireza; Mohammadi, Mahdi; Rashedi, Fariborz; Ghasemi, Ardavan
2016-01-01
Background: In the present study, the epidemiologic aspects of road traffic crashes in South East of Iran are described. Methods: This cross-sectional study included the profile of 2398 motor vehicle crashes recorded in the police office in one Year in South East of Iran. Data collected included: demographics, the type of crash, type of involved vehicle, location of crash and factors contributing to the crash. Descriptive statistics were used for data analysis. Results: Collisions with other vehicles or objects contributed the highest proportion (62.4%) of motor vehicle crashes. Human factors including careless driving, violating traffic laws, speeding, and sleep deprivation/fatigue were the most important causal factors accounting for 90% of road crashes. Data shows that 41% of drivers were not using a seat belt at the time of crash. One- third of the crashes resulted in injury (25%) or death (5%). Conclusions: Reckless driving such as speeding and violation of traffic laws are major risk factors for crashes in the South East of Iran. This highlights the need for education along with traffic law enforcement to reduce motor vehicle crashes in future. PMID:27157159
The Pattern of Road Traffic Crashes in South East Iran.
Rad, Mahdieh; Martiniuk, Alexandra Lc; Ansari-Moghaddam, Alireza; Mohammadi, Mahdi; Rashedi, Fariborz; Ghasemi, Ardavan
2016-09-01
In the present study, the epidemiologic aspects of road traffic crashes in South East of Iran are described. This cross-sectional study included the profile of 2398 motor vehicle crashes recorded in the police office in one Year in South East of Iran. Data collected included: demographics, the type of crash, type of involved vehicle, location of crash and factors contributing to the crash. Descriptive statistics were used for data analysis. Collisions with other vehicles or objects contributed the highest proportion (62.4%) of motor vehicle crashes. Human factors including careless driving, violating traffic laws, speeding, and sleep deprivation/fatigue were the most important causal factors accounting for 90% of road crashes. Data shows that 41% of drivers were not using a seat belt at the time of crash. One- third of the crashes resulted in injury (25%) or death (5%). Reckless driving such as speeding and violation of traffic laws are major risk factors for crashes in the South East of Iran. This highlights the need for education along with traffic law enforcement to reduce motor vehicle crashes in future.
2010 South Dakota motor vehicle traffic crash summary
DOT National Transportation Integrated Search
2011-01-01
The Motor Vehicle Traffic Crash Summary is divided into two main sections, Historical Trends and 2010 Motor Vehicle Traffic Crash Profile. The Historical Trend section provides information on alcohol involvement in motor vehicle crashes, severity of ...
Considering built environment and spatial correlation in modeling pedestrian injury severity.
Prato, Carlo G; Kaplan, Sigal; Patrier, Alexandre; Rasmussen, Thomas K
2018-01-02
This study looks at mitigating and aggravating factors that are associated with the injury severity of pedestrians when they have crashes with another road user and overcomes existing limitations in the literature by focusing attention on the built environment and considering spatial correlation across crashes. Reports for 6,539 pedestrian crashes occurred in Denmark between 2006 and 2015 were merged with geographic information system resources containing detailed information about the built environment and exposure at the crash locations. A linearized spatial logit model estimated the probability of pedestrians sustaining a severe or fatal injury conditional on the occurrence of a crash with another road user. This study confirms previous findings about older pedestrians and intoxicated pedestrians being the most vulnerable road users and crashes with heavy vehicles and in roads with higher speed limits being related to the most severe outcomes. This study provides novel perspectives by showing positive spatial correlations of crashes with the same severity outcomes and emphasizing the role of the built environment in the proximity of the crash. This study emphasizes the need for thinking about traffic calming measures, illumination solutions, road maintenance programs, and speed limit reductions. Moreover, this study emphasizes the role of the built environment, because shopping areas, residential areas, and walking traffic density are positively related to a reduction in pedestrian injury severity. Often, these areas have in common a larger pedestrian mass that is more likely to make other road users more aware and attentive, whereas the same does not seem to apply to areas with lower pedestrian density.
Huang, Helai; Peng, Yunying; Wang, Jie; Luo, Qizhang; Li, Xiang
2018-02-01
Traffic safety of freeways has attracted major concerns, especially for a mountainous freeway affected by adverse terrain conditions, constrained roadway geometry and complicated driving environments. On the basis of a comprehensive dataset collected from a mountainous freeway with a length of 61km but gathering 12 tunnels, this study seeks to examining the interactive effect of mountainous freeway alignment, driving behaviors, vehicle characteristics and environmental factors on crash severity. A classification and regression tree (CART) model is employed as it can deal with high-order interactions between explanatory variables. Results show that the driving behavior is the most important determinant for injury severity of mountainous freeway crashes, followed by the crash time, grade, curve radius and vehicle type. These variables, interacted with the factors of season and crash location, may largely account for the likelihood of high risk events which may result in severe crashes. Events associated with a notably higher probability of severe crashes include coach drivers involved in improper lane changing and other improper actions, drivers involved in speeding during afternoon or evening, drivers involved in speeding along large curve and straight segment during morning, noon or night, and drivers involved in fatigue while passing along the downgrade. Safety interventions to prevent severe crashes at the mountainous freeway include hierarchical supervision in terms of hazardous driving events, enhanced enforcement for speeding and fatigue driving, deployment of advanced driving assistance systems for fatigue driving warning, and cumulative driving time monitoring for long-distance-travel freight vehicles. Copyright © 2017 Elsevier Ltd. All rights reserved.
Stübig, Timo; Brand, Stephan; Zeckey, Christian; Beltran, Michael J; Otte, Dietmar; Krettek, Christian; Haasper, Carl
2013-01-01
Thoracic injuries are common in vehicle crashes, but only a few studies thus far have analysed the relationship between injury characteristics and collision details and discussed the possible implications for future vehicle design and prevention. In this study, the crash details were prospectively collected at the scene of injury between 2004 and 2009 for severely injured patients. The collected data included the type of collision, angle of impact and change of velocity on impact as well as injury characteristics and patient demographics, including abbreviated injury scale (AIS) and injury severity score (ISS).There were 5998 accidents involving 8830 patients over this five-year period; 31 met the inclusion criteria (23 males and eight females). The mean ISS was 37 ± 12.68, the mean AIS Thorax was 4.0. Lung contusions were found in 90% of the patients, pneumothoraces in 58% and rib fractures in 81%. There was a significant relationship between accident deceleration speed (ΔV), AIS Thorax (p = 0.02) and the incidence of pneumothoraces (p = 0.046). The analysis showed a high overall incidence of thoracic injuries in car passengers. Future improvements in automobile safety and design should seek to reduce the incidence of thoracic injuries by uniform vehicle deformation and further implementation of side airbags.
Trends and characteristics of animal-vehicle collisions in the United States.
Sullivan, John M
2011-02-01
Since 1990, fatal animal-vehicle collisions (AVCs) in the United States have more than doubled. This paper examines annual AVC trends in the United States over a 19-year period, seasonal and diurnal patterns of AVC risk, the geographic distribution of crash risk by state, and the association between posted speed limit and AVC crash risk in darkness. AVCs were compiled from the Fatality Analysis Reporting System (FARS) and the General Estimates System (GES) for the years 1990-2008 to examine annual crash trends for fatal and nonfatal crashes. Seasonal trends for fatal AVCs were examined with the aggregated FARS dataset; seasonal trends for fatal and nonfatal AVCs were also examined by aggregating four years of Michigan crash data. State-by-state distributions of fatal AVCs were also described with the aggregated FARS dataset. Finally, the relationship between posted speed limit and the odds that a fatal or nonfatal AVC occurred in darkness were examined with logistic regressions using the aggregated FARS and Michigan datasets. Between 1990 and 2008, fatal AVCs increased by 104% and by 1.3 crashes per trillion vehicle miles travelled per year. Although not all AVCs involve deer, daily and seasonal AVC crash trends follow the general activity pattern of deer populations, consistent with prior reports. The odds that a fatal AVC occurred in darkness were also found to increase by 2.3% for each mile-per-hour increase in speed; a similar, albeit smaller, effect was also observed in the aggregated Michigan dataset, among nonfatal crashes. AVCs represent a small but increasing share of crashes in the United States. Seasonal and daily variation in the pattern of AVCs seem to follow variation in deer exposure and ambient light level. Finally, the relative risk that a fatal and nonfatal AVC occurred in darkness is influenced by posted speed limit, suggesting that a driver's limited forward vision at night plays a role in AVCs, as it does in pedestrian collisions. The association between speed limit and crash risk in darkness suggests that AVC risk might be reduced with countermeasures that improve a driver's forward view of the road. Copyright © 2010 Elsevier Ltd. All rights reserved.
Risk factors for the severity of injury incurred in crashes involving on-duty police cars.
Chu, Hsing-Chung
2016-07-03
This article explores the risk factors associated with police cars on routine patrol and/or on an emergency run and their effects on the severity of injuries in crashes. The binary probit model is used to examine the effects of important factors on the risk of injuries sustained in crashes involving on-duty police cars. Several factors significantly increase the probability of crashes that cause severe injuries. Among those causes are police officers who drive at excessive speeds, traffic violations during emergency responses or pursuits, and driving during the evening (6 to 12 p.m.) or in rainy weather. Findings also indicate some potential issues associated with an increase in the probability of crashes that cause injuries. Younger police drivers were found to be more likely to be involved in crashes causing injuries than middle-aged drivers were. Distracted driving by on-duty police officers as well as civilian drivers who did not pull over to let a police car pass in emergency situations also caused serious crashes. Police cars are exempted from certain traffic laws under emergency circumstances. However, to reduce the probability of being involved in a crash resulting in severe injuries, officers are still obligated to drive safely and follow safety procedures when responding to emergencies or pursuing a car. Enhancement of training techniques for emergency situations or driving in pursuit of an offender and following the safety procedures are essential for safety in driving during an emergency run by police.
Isaksson-Hellman, Irene; Lindman, Magdalena
2016-09-01
The aim of the present study was to evaluate the crash mitigation performance of low-speed automated emergency braking collision avoidance technologies by examining crash rates, car damage, and personal injuries. Insurance claims data were used to identify rear-end frontal collisions, the specific situations where the low-speed automated emergency braking system intervenes. We compared cars of the same model (Volvo V70) with and without the low-speed automated emergency braking system (AEB and no AEB, respectively). Distributions of spare parts required for car repair were analyzed to identify car damage, and crash severity was estimated by comparing the results with laboratory crash tests. Repair costs and occupant injuries were investigated for both the striking and the struck vehicle. Rear-end frontal collisions were reduced by 27% for cars with low-speed AEB compared to cars without the system. Those of low severity were reduced by 37%, though more severe crashes were not reduced. Accordingly, the number of injured occupants in vehicles struck by low-speed AEB cars was reduced in low-severity crashes. In offset crash configurations, the system was found to be less effective. This study adds important information about the safety performance of collision avoidance technologies, beyond the number of crashes avoided. By combining insurance claims data and information from spare parts used, the study demonstrates a mitigating effect of low-speed AEB in real-world traffic.
Commercial bus crashes in North Carolina 1995-1999
DOT National Transportation Integrated Search
2000-04-01
Tables and figures are shown to depict a statistical representation of commercial bus crashes in North Carolina. Information displayed includes crash frequency, crashes by county, accident severity, time of day, month of the year, class of roadway, r...
Crashes involving farm tractors and other farm vehicles/equipment in North Carolina 1995-1999
DOT National Transportation Integrated Search
2000-04-01
Tables and figures are shown to depict a statistical representation of crashes involving farm tractors and other farm vehicles or equipment, in North Carolina. Information displayed includes crash frequency, crashes by county, accident severity, type...
Characteristics and contributory causes related to large truck crashes (phase II) : all crashes.
DOT National Transportation Integrated Search
2012-03-01
Statistics clearly demonstrate that large-truck crashes contribute to a significant percentage of high-severity crashes. It is : therefore important for the highway safety community to identify the characteristics and contributory causes of these typ...
Singleton, Michael; Qin, Huifang; Luan, Jingyu
2004-06-01
The majority of motor vehicle occupants who were killed or hospitalized in crashes in Kentucky in 2000-2001 occupied vehicles that were severely damaged in the crash. Even so, overall only a small percentage of all severely damaged vehicle occupants were killed or hospitalized. The purpose was to identify occupant, vehicle, crash, and roadway/environmental factors that were associated with increased risk of severe injury in crashes where the occupant's vehicle was severely damaged. This study probabilistically linked Kentucky's statewide motor vehicle crash and inpatient hospital discharge data files for 2000 and 2001, and selected cases representing occupants of vehicles that were reported by police as having either "severe" or "very severe" damage. For occupants who were identified through data linkage as having been hospitalized, the Injury Severity Score (ISS) was calculated using ICDMAP-90 software, and the scores were stratified into the following categories: critical (>24), severe (15-24), moderate (9-14), and mild (<9). We then created an outcome variable, injury severity level, with five levels: killed; hospitalized with at least moderate injuries (ISS = critical, severe, or moderate); hospitalized with mild injuries (ISS = mild); injured according to the police report but not hospitalized; and no apparent injury according to the police report. We performed a stepwise, ordinal logistic regression of injury severity, using independent variables identified from the existing crash literature. Occupant risk factors for higher levels of injury severity selected by the regression were age (risk increased with age, other factors being equal), female gender, restraint non-use, ejection from the vehicle, and driver impairment (by alcohol and/or drugs). Crash risk factors included head-on collision, collision with a fixed object, vehicle rollover, and vehicle fire. Roadway/environmental factors were federal- or state-maintained roadway and posted speed limit 89 kph (55 mph) or greater. Many of the identified risk factors are explicitly or implicitly mentioned in the strategic plans of key organizations involved in highway safety and injury prevention in Kentucky. Our analysis provides additional evidence of their importance, and confirms that their mitigation will reduce injury severity in crashes involving severe vehicle damage. Additionally, older occupants and female occupants showed increased risks of serious injury, but to our knowledge these factors are not currently addressed in any state plans. An opportunity exists to clarify the nature of these risks through further studies, which might lead to the identification of countermeasures specific to these populations.
Characteristics of the Injury Environment in Far-Side Crashes
Digges, K.; Gabler, H; Mohan, P.; Alonso, B.
2005-01-01
The population of occupants in far-side crashes that are documented in the US National database (NASS/CDS) was studied. The annual number of front seat occupants with serious or fatal injuries in far-side planar and rollover crashes was 17,194. The crash environment that produces serious and fatal injuries to belted front seat occupants in planar far-side crashes was investigated in detail. It was found that both the change in velocity and extent of damage were important factors that relate to crash severity. The median severity for crashes with serious or fatal injuries was a lateral delta-V of 28 kph and an extent of damage of CDC 3.6. Vehicle-to-vehicle impacts were simulated by finite element models to determine the intrusion characteristics associated with the median crash condition. These simulations indicated that the side damage caused by the IIHS barrier was representative of the damage in crashes that produce serious injuries in far-side crashes. Occupant simulations of the IIHS barrier crash at 28 kph showed that existing dummies lack biofidelity in upper body motion. The analysis suggested test conditions for studying far-side countermeasures and supported earlier studies that showed the need for an improved dummy to evaluate safety performance in the far-side crash environment. PMID:16179148
Figler, Bradley D; Mack, Christopher D; Kaufman, Robert; Wessells, Hunter; Bulger, Eileen; Smith, Thomas G; Voelzke, Bryan
2014-03-01
The National Highway Traffic Safety Administration's New Car Assessment Program (NCAP) implemented side-impact crash testing on all new vehicles since 1998 to assess the likelihood of major thoracoabdominal injuries during a side-impact crash. Higher crash test rating is intended to indicate a safer car, but the real-world applicability of these ratings is unknown. Our objective was to determine the relationship between a vehicle's NCAP side-impact crash test rating and the risk of major thoracoabdominal injury among the vehicle's occupants in real-world side-impact motor vehicle crashes. The National Automotive Sampling System Crashworthiness Data System contains detailed crash and injury data in a sample of major crashes in the United States. For model years 1998 to 2010 and crash years 1999 to 2010, 68,124 occupants were identified in the Crashworthiness Data System database. Because 47% of cases were missing crash severity (ΔV), multiple imputation was used to estimate the missing values. The primary predictor of interest was the occupant vehicle's NCAP side-impact crash test rating, and the outcome of interest was the presence of major (Abbreviated Injury Scale [AIS] score ≥ 3) thoracoabdominal injury. In multivariate analysis, increasing NCAP crash test rating was associated with lower likelihood of major thoracoabdominal injury at high (odds ratio [OR], 0.8; 95% confidence interval [CI], 0.7-0.9; p < 0.01) and medium (OR, 0.9; 95% CI, 0.8-1.0; p < 0.05) crash severity (ΔV), but not at low ΔV (OR, 0.95; 95% CI, 0.8-1.2; p = 0.55). In our model, older age and absence of seat belt use were associated with greater likelihood of major thoracoabdominal injury at low and medium ΔV (p < 0.001), but not at high ΔV (p ≥ 0.09). Among adults in model year 1998 to 2010 vehicles involved in medium and high severity motor vehicle crashes, a higher NCAP side-impact crash test rating is associated with a lower likelihood of major thoracoabdominal trauma. Epidemiologic study, level III.
Shults, Ruth A; Williams, Allan F
2017-09-01
The Monitoring the Future (MTF) survey provides nationally-representative annual estimates of licensure and driving patterns among U.S. teens. A previous study using MTF data reported substantial declines in the proportion of high school seniors that were licensed to drive and increases in the proportion of nondrivers following the recent U.S. economic recession. To explore whether licensure and driving patterns among U.S. high school seniors have rebounded in the post-recession years, we analyzed MTF licensure and driving data for the decade of 2006-2015. We also examined trends in teen driver involvement in fatal and nonfatal injury crashes for that decade using data from the Fatality Analysis Reporting System and National Automotive Sampling System General Estimates System, respectively. During 2006-2015, the proportion of high school seniors that reported having a driver's license declined by 9 percentage points (11%) from 81% to 72% and the proportion that did not drive during an average week increased by 8 percentage points (44%) from 18% to 26%. The annual proportion of black seniors that did not drive was consistently greater than twice the proportion of nondriving white seniors. Overall during the decade, 17- and 18-year-old drivers experienced large declines in fatal and nonfatal injury crashes, although crashes increased in both 2014 and 2015. The MTF data indicate that licensure and driving patterns among U.S. high school seniors have not rebounded since the economic recession. The recession had marked negative effects on teen employment opportunities, which likely influenced teen driving patterns. Possible explanations for the apparent discrepancies between the MTF data and the 2014 and 2015 increases in crashes are explored. MTF will continue to be an important resource for clarifying teen driving trends in relation to crash trends and informing strategies to improve teen driver safety. Published by Elsevier Ltd.
DOT National Transportation Integrated Search
2015-03-01
Lane departure crashes including single-vehicle-run-off-road crashes, opposite direction sideswipe and head-on crashes are considered the most sever : crashes and often dominated by sleep deprivation/fatigue, and distracted driving. According to the ...
Crash cost estimates by maximum police-reported injury severity within selected crash geometrics
DOT National Transportation Integrated Search
2005-10-01
This paper presents estimates for the economic (human capital) and comprehensive costs per crash for six KABCO groupings within 22 selected crash types and within two speed limit categories (=80 km/h (>= 50 mi/h)). The comp...
Evaluation of the locations of Kentucky's traffic crash data.
DOT National Transportation Integrated Search
2010-11-01
An evaluation of a random sample of crashes from 2009 was performed to assess the current accuracy of the crash data's location information.The location of the crash was compared to the presumed location using several report data elements such as nea...
NASA Astrophysics Data System (ADS)
Effati, Meysam; Thill, Jean-Claude; Shabani, Shahin
2015-04-01
The contention of this paper is that many social science research problems are too "wicked" to be suitably studied using conventional statistical and regression-based methods of data analysis. This paper argues that an integrated geospatial approach based on methods of machine learning is well suited to this purpose. Recognizing the intrinsic wickedness of traffic safety issues, such approach is used to unravel the complexity of traffic crash severity on highway corridors as an example of such problems. The support vector machine (SVM) and coactive neuro-fuzzy inference system (CANFIS) algorithms are tested as inferential engines to predict crash severity and uncover spatial and non-spatial factors that systematically relate to crash severity, while a sensitivity analysis is conducted to determine the relative influence of crash severity factors. Different specifications of the two methods are implemented, trained, and evaluated against crash events recorded over a 4-year period on a regional highway corridor in Northern Iran. Overall, the SVM model outperforms CANFIS by a notable margin. The combined use of spatial analysis and artificial intelligence is effective at identifying leading factors of crash severity, while explicitly accounting for spatial dependence and spatial heterogeneity effects. Thanks to the demonstrated effectiveness of a sensitivity analysis, this approach produces comprehensive results that are consistent with existing traffic safety theories and supports the prioritization of effective safety measures that are geographically targeted and behaviorally sound on regional highway corridors.
Sasidharan, Lekshmi; Wu, Kun-Feng; Menendez, Monica
2015-12-01
One of the major challenges in traffic safety analyses is the heterogeneous nature of safety data, due to the sundry factors involved in it. This heterogeneity often leads to difficulties in interpreting results and conclusions due to unrevealed relationships. Understanding the underlying relationship between injury severities and influential factors is critical for the selection of appropriate safety countermeasures. A method commonly employed to address systematic heterogeneity is to focus on any subgroup of data based on the research purpose. However, this need not ensure homogeneity in the data. In this paper, latent class cluster analysis is applied to identify homogenous subgroups for a specific crash type-pedestrian crashes. The manuscript employs data from police reported pedestrian (2009-2012) crashes in Switzerland. The analyses demonstrate that dividing pedestrian severity data into seven clusters helps in reducing the systematic heterogeneity of the data and to understand the hidden relationships between crash severity levels and socio-demographic, environmental, vehicle, temporal, traffic factors, and main reason for the crash. The pedestrian crash injury severity models were developed for the whole data and individual clusters, and were compared using receiver operating characteristics curve, for which results favored clustering. Overall, the study suggests that latent class clustered regression approach is suitable for reducing heterogeneity and revealing important hidden relationships in traffic safety analyses. Copyright © 2015 Elsevier Ltd. All rights reserved.
Modeling crash injury severity by road feature to improve safety.
Penmetsa, Praveena; Pulugurtha, Srinivas S
2018-01-02
The objective of this research is 2-fold: to (a) model and identify critical road features (or locations) based on crash injury severity and compare it with crash frequency and (b) model and identify drivers who are more likely to contribute to crashes by road feature. Crash data from 2011 to 2013 were obtained from the Highway Safety Information System (HSIS) for the state of North Carolina. Twenty-three different road features were considered, analyzed, and compared with each other as well as no road feature. A multinomial logit (MNL) model was developed and odds ratios were estimated to investigate the effect of road features on crash injury severity. Among the many road features, underpass, end or beginning of a divided highway, and on-ramp terminal on crossroad are the top 3 critical road features. Intersection crashes are frequent but are not highly likely to result in severe injuries compared to critical road features. Roundabouts are least likely to result in both severe and moderate injuries. Female drivers are more likely to be involved in crashes at intersections (4-way and T) compared to male drivers. Adult drivers are more likely to be involved in crashes at underpasses. Older drivers are 1.6 times more likely to be involved in a crash at the end or beginning of a divided highway. The findings from this research help to identify critical road features that need to be given priority. As an example, additional advanced warning signs and providing enlarged or highly retroreflective signs that grab the attention of older drivers may help in making locations such as end or beginning of a divided highway much safer. Educating drivers about the necessary skill sets required at critical road features in addition to engineering solutions may further help them adopt safe driving behaviors on the road.
Direct medical costs of motorcycle crashes in Ontario
Pincus, Daniel; Wasserstein, David; Nathens, Avery B.; Bai, Yu Qing; Redelmeier, Donald A.; Wodchis, Walter P.
2017-01-01
BACKGROUND: There is no reliable estimate of costs incurred by motorcycle crashes. Our objective was to calculate the direct costs of all publicly funded medical care provided to individuals after motorcycle crashes compared with automobile crashes. METHODS: We conducted a population-based, matched cohort study of adults in Ontario who presented to hospital because of a motorcycle or automobile crash from 2007 through 2013. For each case, we identified 1 control absent a motor vehicle crash during the study period. Direct costs for each case and control were estimated in 2013 Canadian dollars from the payer perspective using methodology that links health care use to individuals over time. We calculated costs attributable to motorcycle and automobile crashes within 2 years using a difference-in-differences approach. RESULTS: We identified 26 831 patients injured in motorcycle crashes and 281 826 injured in automobile crashes. Mean costs attributable to motorcycle and automobile crashes were $5825 and $2995, respectively (p < 0.001). The rate of injury was triple for motorcycle crashes compared with automobile crashes (2194 injured annually/100 000 registered motorcycles v. 718 injured annually/100 000 registered automobiles; incidence rate ratio [IRR] 3.1, 95% confidence interval [CI] 2.8 to 3.3, p < 0.001). Severe injuries, defined as those with an Abbreviated Injury Scale ≥ 3, were 10 times greater (125 severe injuries annually/100 000 registered motorcycles v. 12 severe injuries annually/100 000 registered automobiles; IRR 10.4, 95% CI 8.3 to 13.1, p < 0.001). INTERPRETATION: Considering both the attributable cost and higher rate of injury, we found that each registered motorcycle in Ontario costs the public health care system 6 times the amount of each registered automobile. Medical costs may provide an additional incentive to improve motorcycle safety. PMID:29158454
Rizzi, Matteo; Strandroth, Johan; Tingvall, Claes
2009-10-01
This study set out to evaluate the effectiveness of antilock brake system (ABS) technology on motorcycles in reducing real-life injury crashes and to mitigate injury severity. The study comprised an analysis of in-depth fatal crash data in Sweden during 2005-2008 to investigate the potential of ABS as well an estimate of the effectiveness of ABS in crash reduction in Sweden between 2003 and 2008 using induced exposure methods. Findings show that head-on collisions were the least ABS-affected crash types and collisions at intersections the most influenced. Induced exposure analysis showed that the overall effectiveness of ABS was 38 percent on all crashes with injuries and 48 percent on all severe and fatal crashes, with a minimum effectiveness of 11 and 17 percent, respectively. The study recommends the fitment of ABS on all new motorcycles as soon as possible and that customers only purchase motorcycles with ABS.
Bener, Abdulbari; Rahman, Yassir S Abdul; Mitra, Biswadev
2009-01-01
Head and neck injuries following the road traffic crashes (RTCs) are the most common cause of morbidity and mortality in most developed and developing countries and may also result in temporary or permanent disability. The aim of this study was to determine the incidence pattern of head and neck injuries, investigate its trend and identify the severity of injuries involved with road traffic crashes (RTCs) during the period 2001-2006. This is a retrospective descriptive hospital based study. The patients with head and neck injuries were seen and treated in the Accident and Emergency Department of the Hamad General Hospital and other Trauma Centers of the Hamad Medical Corporation following the road traffic crashes during the period 2001-2006. This study is a retrospective analysis of 6709 patients attended and treated at the Accident and Emergency and Trauma centers for head and neck injuries over a 6 year period. Head and neck injuries were determined according to the ICD 10 criteria. Of these, 3013 drivers, 2502 passengers, 704 pedestrians and 490 two wheel riders (motor bike and cyclists). Details of all the road traffic crash patients were compiled in the database of the Emergency Medical Services (EMS), and the data of patients with head and neck injuries were extracted from this database. A total of 6709 patients with head and neck injuries was reported during the study period. Majority of the victims were non-Qataris (68.7%), men (85.9%) and in the age group 20-44 years (68.5%). There were statistical significant differences in relation to age, nationality, gender, and accident during week ends for head and neck injuries (p<0.001). The male to female ratio for head and neck injury was 6.1:1. There was a disproportionately higher incidence of accidents during weekends (27.8%). Majority of the patients had mild injury (87.2%), followed by moderate (7.3%) and severe (5.5%). The highest frequency of head injury was among the young adults 20-44 years (68.5%). There was a remarkable increase in the incidence rate of head and neck injuries per 10,000 population in the year 2005 (18.2) compared to previous years and declined slightly in the year 2006 (17.1). Overall, the incidence of head and neck injuries from road traffic crashes are increasing. The present study findings provided an overview of head and neck injuries in Qatar from road traffic crashes. The incidence of head and neck injuries is still very high in Qatar, but the severity of injury was mild in most of the victims. The findings of the study highlighted the need for taking urgent steps for safety of people especially drivers and passengers.
Identification of CRASH, a gene deregulated in gynecological tumors.
Evtimova, Vesna; Zeillinger, Robert; Kaul, Sepp; Weidle, Ulrich H
2004-01-01
We have identified CRASH, a human asparaginase-like protein which is composed of 308 amino acids and exhibits 32% homology to human aspartylglucosaminadase at the amino acid level. Database analysis revealed that the gene corresponding to CRASH is composed of 7 exons and 6 introns. Steady-state level of CRASH mRNA was found to be increased in 5 cell lines derived from metastatic lesions compared with 2 cell lines derived from primary mammary carcinoma and HMEC (human mammary epithelial cells). We found that the mRNA level of CRASH correlates with the metastatic propensity of several isogenic human colon cancer and pancreatic carcinoma cell lines. CRASH corresponds to a recently identified sperm autoantigen and furthermore we have demonstrated inducibility of CRASH mRNA by androgen and progesterone. Investigation of several types of human cancers and their corresponding normal tissues revealed high levels of CRASH mRNA in uterine, mammary and ovarian tumors compared with the corresponding normal tissues. CRASH mRNA expression was analysed in breast cancer samples with disclosed clinico-pathological features and corresponding normal tissues. The levels of CRASH mRNA were significantly up-regulated in tumors compared with normal breast tissues and correlate with lack of estrogen receptor expression of the tumors.
Evaluation of pedestrian road traffic maxillofacial injuries in a Nigerian tertiary hospital.
Aladelusi, T O; Akinmoladun, I V; Olusanya, O O; Akadiri, O A; Fasola, A O
2014-12-01
Background: Walking is the most basic form of mobility and forms an important part of daily activities; however, walking could often be associated with risks. This is more so when pedestrians share a common space with motorized vehicles especially in developing countries. Despite the frequency of road traffic crashes (RTC) related pedestrian injuries in many developing countries, there is a dearth of documentation of maxillofacial injuries in victims of pedestrian road traffic crashes. The aim of this study was to determine the causes, frequency, pattern, severity, concomitant injuries and outcome of pedestrian maxillofacial injuries observed at a tertiary trauma centre in Nigeria. Pedestrian victims of RTC were prospectively recruited from among all maxillofacial trauma patients seen at the Accident and Emergency department and the Department of Oral and Maxillofacial Surgery of the University College Hospital, Ibadan between April 2011 and November 2011. Ethical approval was obtained from the UI/UCH Joint Ethics Review Board before the commencement of the study and informed consent was obtained from participants. Patients' demography, the crash events, types of maxillofacial injuries, and concomitant injuries were recorded. Severity of maxillofacial injury was estimated based on the Maxillofacial Injury Severity Scale (MFISS). Forty-six participants (22.9% of all victims of road traffic crashes seen within the study period) were victims of pedestrian RTC. Pedestrian RTC occurred in all age groups with almost 40% of the victims in their 1st and 2nd decades of life. The most severe MFISS was observed in the 21 - 30 year age group while the least severe injury observed was in the 71 - 80 years age group. Thirty participants (65.2%) were hit by a car or minibus while fourteen (30.4%) were knocked down by a motorcycle. Two (4.4%) were hit by a truck. Soft tissue injury was the most common maxillofacial injury and head injury was the commonest concomitant injury observed. The median MFISS score of victims of motorcycle was 4.0 while the median scores for victims of car/minibus pedestrian RTC was 9.0. The most severe maxillofacial injury was seen in victim of car/minibus pedestrian crashes. Seventeen percent (8) of the victims had a fatal outcome. Conclusion: Pedestrian RTC resulting in maxillofacial injuries are common in the studied environment. It is particularly common among the 11 -20 year age group and victims are usually hit by cars/minibuses. These injuries are often severe and fatal outcome is not infrequent. Therefore, definitive preventive measures are imperative.
Kim, Jong-Eun; Kim, Hwan; Shum, Phillip C.; Shih, Alan M.; Pintar, Frank; Shen, Wei; Ma, Xiaoguang; Laud, Purushottam W.; Heymsfield, Steven B.; Allison, David B.; Zhu, Shankuan
2015-01-01
The objective of this study was to examine the role of body mass and subcutaneous fat in injury severity and pattern sustained by overweight drivers. Finite element models were created to represent the geometry and properties of subcutaneous adipose tissue in the torso with data obtained from reconstructed magnetic resonance imaging datasets. The torso adipose tissue models were then integrated into the standard multibody dummy models together with increased inertial parameters and sizes of the limbs to represent overweight occupants. Frontal crash simulations were performed considering a variety of occupant restraint systems and regional body injuries were measured. The results revealed that differences in body mass and fat distribution have an impact on injury severity and pattern. Even though the torso adipose tissue of overweight subjects contributed to reduce abdominal injury, the momentum effect of a greater body mass of overweight subjects was more dominant over the cushion effect of the adipose tissue, increasing risk of other regional body injuries except abdomen. Through statistical analysis of the results, strong correlations (p < 0.01) were found between body mass index and regional body injuries except neck injury. The analysis also revealed that a greater momentum of overweight males leads to greater forward torso and pelvic excursions that account for higher risks (p < 0.001) of head, thorax, and lower extremity injury than observed in non-overweight males. The findings have important implications for improving the vehicle and occupant safety systems designed for the increasing global obese population. PMID:23113549
Effect of electronic stability control on automobile crash risk.
Farmer, Charles
2004-12-01
Per vehicle crash involvement rates were compared for otherwise identical vehicle models with and without electronic stability control (ESC) systems. ESC was found to affect single-vehicle crashes to a greater extent than multiple-vehicle crashes, and crashes with fatal injuries to a greater extent than less severe crashes. Based on all police-reported crashes in 7 states over 2 years, ESC reduced single-vehicle crash involvement risk by approximately 41 percent (95 percent confidence limits 3348) and single-vehicle injury crash involvement risk by 41 percent (2752). This translates to an estimated 7 percent reduction in overall crash involvement risk (310) and a 9 percent reduction in overall injury crash involvement risk (314). Based on all fatal crashes in the United States over 3 years, ESC was found to have reduced single-vehicle fatal crash involvement risk by 56 percent (3968). This translates to an estimated 34 percent reduction in overall fatal crash involvement risk (2145).
Risk and type of crash among young drivers by rurality of residence: findings from the DRIVE Study.
Chen, H Y; Ivers, R Q; Martiniuk, A L C; Boufous, S; Senserrick, T; Woodward, M; Stevenson, M; Williamson, A; Norton, R
2009-07-01
Most previous literature on urban/rural differences in road crashes has a primary focus on severe injuries or deaths, which may be largely explained by variations of medical resources. Little has been reported on police-reported crashes by geographical location, or crash type and severity, especially among young drivers. DRIVE is a prospective cohort study of 20,822 drivers aged 17-24 in NSW, Australia. Information on risk factors was collected via online questionnaire and subsequently linked to police-reported crashes. Poisson regression was used to analyse risk of various crash types by three levels of rurality of residence: urban, regional (country towns and surrounds) and rural. Compared to urban drivers, risk of crash decreased with increasing rurality (regional adjusted RR: 0.7, 95% CI 0.6-0.9; rural adjusted RR: 0.5, 95% CI 0.3-0.7). Among those who crashed, risk of injurious crash did not differ by geographic location; however, regional and rural drivers had significantly higher risk of a single versus multiple vehicle crash (regional adjusted RR 1.8, 95% CI 1.3-2.5; rural adjusted RR: 2.0, 95% CI 1.1-3.6), which was explained by speeding involvement and road alignment at the time or site of crash. Although young urban drivers have a higher crash risk overall, rural and regional residents have increased risk of a single vehicle crash. Interventions to reduce single vehicle crashes should aim to address key issues affecting such crashes, including speeding and specific aspects of road geometry.
Maltese, Matthew R.; Chen, Irene G.; Arbogast, Kristy B.
2005-01-01
Previous work identified a similar risk of injury for children seated on the struck side and center rear in side impact crashes in passenger cars. In order to further explain this finding, we investigated the effect of sharing the rear row with other occupants on injury risk and delineated differences in injury patterns among the seat positions. These analyses, conducted from a large child specific crash surveillance system, included: children 4–15 years old, rear seated, seat belt restrained, in a passenger car, and in a side impact crash. Injury risk was compared among each rear seat position stratified by the presence of other occupants on the rear row. Occupants are at an increased risk of injury if they sit alone on their row as compared to sitting with other occupants. Patterns of injuries distinct to each seat position were delineated. PMID:16179151
DOE Office of Scientific and Technical Information (OSTI.GOV)
Barancik, J.I.; Kramer, C.F.; Thode, H.C. Jr.
On January 25, 1990 Avianca Flight 052 crashed without a conflagration after running out of fuel; 73 persons died, 85 survived. Epidemiological, biostatistical, and related analytical methods were used for the analysis of decedent and survivor injury patterns and for the purpose of examining selected EMS and hospital issues-relative to disaster planning and incident management and response. Medical examiner and hospital records for all decedents and survivors were identified, abstracted, and coded using the International Classification of Diseases with Clinical Modifications, 9th Edition (ICD 9-CM) to determine the nature of injuries and comorbid conditions. Injury severity values were determined usingmore » the 1985 Abbreviated Injury Scale with Epidemiologic Modifications (AIS 85-EM).« less
Effect of speed limit increase on crash rate on rural two-lane highways in Louisiana.
DOT National Transportation Integrated Search
2006-08-01
This study investigated the impact of a speed limit increase on the crash rate on rural twolane roads in Louisiana. The Louisiana crash database for 1999-2004 was used to compare rates of different crash severities and types before and after a speed ...
Investigation of work zone crash casualty patterns using association rules.
Weng, Jinxian; Zhu, Jia-Zheng; Yan, Xuedong; Liu, Zhiyuan
2016-07-01
Investigation of the casualty crash characteristics and contributory factors is one of the high-priority issues in traffic safety analysis. In this paper, we propose a method based on association rules to analyze the characteristics and contributory factors of work zone crash casualties. A case study is conducted using the Michigan M-94/I-94/I-94BL/I-94BR work zone crash data from 2004 to 2008. The obtained association rules are divided into two parts including rules with high-lift, and rules with high-support for the further analysis. The results show that almost all the high-lift rules contain either environmental or occupant characteristics. The majority of association rules are centered on specific characteristics, such as drinking driving, the highway with more than 4 lanes, speed-limit over 40mph and not use of traffic control devices. It should be pointed out that some stronger associated rules were found in the high-support part. With the network visualization, the association rule method can provide more understandable results for investigating the patterns of work zone crash casualties. Copyright © 2016 Elsevier Ltd. All rights reserved.
Chu, Hsing-Chung
2014-01-01
High-deck buses that have a higher center of gravity traveling at an excessive speed have a higher likelihood of causing serious and fatal accidents when drivers lose control of the vehicle. In addition, drivers who suffer from fatigue in long-distance driving increase the likelihood of serious accident. This paper examines the effects of risk factors contributing to severe crashes associated with high-deck buses used for long-distance driving on freeways. An ordered logit and latent class models are used to examine significant factors on the severity of injuries in crashes related to high-deck buses. Driver fatigue, drivers or passengers not wearing a seat belt, reckless driving, drunk driving, crashes occurred between midnight and dawn, and crashes occurred at interchange ramps were found to significantly affect the severity of injuries in crashes involving high-deck buses. Safety policies to prevent severe injuries in crashes involving high deck buses used for long-distance runs on freeways include: (1) restricting drivers from exceeding the limit of daily driving hours and mandating sufficient rest breaks; (2) installing an automatic sleep-warning device in the vehicle; (3) drivers with obstructive sleep apnea syndrome or sleep disorders should be tested and treated before they are allowed to perform long hours of driving tasks; (4) educating the public or even amending the seatbelt legislation to require all passengers to wear a seat belt and thus reduce the chance of ejection from a high-deck bus and prevent serious injuries in a crash while traveling at a higher speed on freeways. Copyright © 2013 Elsevier Ltd. All rights reserved.
Chand, Sai; Dixit, Vinayak V
2018-03-01
The repercussions from congestion and accidents on major highways can have significant negative impacts on the economy and environment. It is a primary objective of transport authorities to minimize the likelihood of these phenomena taking place, to improve safety and overall network performance. In this study, we use the Hurst Exponent metric from Fractal Theory, as a congestion indicator for crash-rate modeling. We analyze one month of traffic speed data at several monitor sites along the M4 motorway in Sydney, Australia and assess congestion patterns with the Hurst Exponent of speed (H speed ). Random Parameters and Latent Class Tobit models were estimated, to examine the effect of congestion on historical crash rates, while accounting for unobserved heterogeneity. Using a latent class modeling approach, the motorway sections were probabilistically classified into two segments, based on the presence of entry and exit ramps. This will allow transportation agencies to implement appropriate safety/traffic countermeasures when addressing accident hotspots or inadequately managed sections of motorway. Copyright © 2017 Elsevier Ltd. All rights reserved.
Rage against the machine? Google's self-driving cars versus human drivers.
Teoh, Eric R; Kidd, David G
2017-12-01
Automated driving represents both challenges and opportunities in highway safety. Google has been developing self-driving cars and testing them under employee supervision on public roads since 2009. These vehicles have been involved in several crashes, and it is of interest how this testing program compares to human drivers in terms of safety. Google car crashes were coded by type and severity based on narratives released by Google. Crash rates per million vehicle miles traveled (VMT) were computed for crashes deemed severe enough to be reportable to police. These were compared with police-reported crash rates for human drivers. Crash types also were compared. Google cars had a much lower rate of police-reportable crashes per million VMT than human drivers in Mountain View, Calif., during 2009-2015 (2.19 vs 6.06), but the difference was not statistically significant. The most common type of collision involving Google cars was when they got rear-ended by another (human-driven) vehicle. Google cars shared responsibility for only one crash. These results suggest Google self-driving cars, while a test program, are safer than conventional human-driven passenger vehicles; however, currently there is insufficient information to fully examine the extent to which disengagements affected these results. Results suggest that highly-automated vehicles can perform more safely than human drivers in certain conditions, but will continue to be involved in crashes with conventionally-driven vehicles. Copyright © 2017. Published by Elsevier Ltd.
Sleep-related vehicle crashes on low speed roads.
Filtness, A J; Armstrong, K A; Watson, A; Smith, S S
2017-02-01
Very little is known about the characteristics of sleep related (SR) crashes occurring on low speed roads compared with current understanding of the role of sleep in crashes occurring on high speed roads e.g. motorways. To address this gap, analyses were undertaken to identify the differences and similarities between (1) SR crashes occurring on roads with low (≤60km/h) and high (≥100km/h) speed limits, and (2) SR crashes and not-SR crashes occurring on roads with low speed limits. Police reports of all crashes occurring on low and high speed roads over a ten year period between 2000 and 2009 were examined for Queensland, Australia. Attending police officers identified all crash attributes, including 'fatigue/fell asleep', which indicates that the police believe the crash to have a causal factor relating to falling asleep, sleepiness due to sleep loss, time of day, or fatigue. Driver or rider involvement in crashes was classified as SR or not-SR. All crash-associated variables were compared using Chi-square tests (Cramer's V=effect size). A series of logistic regression was performed, with driver and crash characteristics as predictors of crash category. A conservative alpha level of 0.001 determined statistical significance. There were 440,855 drivers or riders involved in a crash during this time; 6923 (1.6%) were attributed as SR. SR crashes on low speed roads have similar characteristics to those on high speed roads with young (16-24y) males consistently over represented. SR crashes on low speed roads are noticeably different to not-SR crashes in the same speed zone in that male and young novice drivers are over represented and outcomes are more severe. Of all the SR crashes identified, 41% occurred on low speed roads. SR crashes are not confined to high speed roads. Low speed SR crashes warrant specific investigation because they occur in densely populated areas, exposing a greater number of people to risk and have more severe outcomes than not-SR crashes on the same low speed roads. Copyright © 2016 Elsevier Ltd. All rights reserved.
Multivariate spatial models of excess crash frequency at area level: case of Costa Rica.
Aguero-Valverde, Jonathan
2013-10-01
Recently, areal models of crash frequency have being used in the analysis of various area-wide factors affecting road crashes. On the other hand, disease mapping methods are commonly used in epidemiology to assess the relative risk of the population at different spatial units. A natural next step is to combine these two approaches to estimate the excess crash frequency at area level as a measure of absolute crash risk. Furthermore, multivariate spatial models of crash severity are explored in order to account for both frequency and severity of crashes and control for the spatial correlation frequently found in crash data. This paper aims to extent the concept of safety performance functions to be used in areal models of crash frequency. A multivariate spatial model is used for that purpose and compared to its univariate counterpart. Full Bayes hierarchical approach is used to estimate the models of crash frequency at canton level for Costa Rica. An intrinsic multivariate conditional autoregressive model is used for modeling spatial random effects. The results show that the multivariate spatial model performs better than its univariate counterpart in terms of the penalized goodness-of-fit measure Deviance Information Criteria. Additionally, the effects of the spatial smoothing due to the multivariate spatial random effects are evident in the estimation of excess equivalent property damage only crashes. Copyright © 2013 Elsevier Ltd. All rights reserved.
Work zone safety analysis and modeling: a state-of-the-art review.
Yang, Hong; Ozbay, Kaan; Ozturk, Ozgur; Xie, Kun
2015-01-01
Work zone safety is one of the top priorities for transportation agencies. In recent years, a considerable volume of research has sought to determine work zone crash characteristics and causal factors. Unlike other non-work zone-related safety studies (on both crash frequency and severity), there has not yet been a comprehensive review and assessment of methodological approaches for work zone safety. To address this deficit, this article aims to provide a comprehensive review of the existing extensive research efforts focused on work zone crash-related analysis and modeling, in the hopes of providing researchers and practitioners with a complete overview. Relevant literature published in the last 5 decades was retrieved from the National Work Zone Crash Information Clearinghouse and the Transport Research International Documentation database and other public digital libraries and search engines. Both peer-reviewed publications and research reports were obtained. Each study was carefully reviewed, and those that focused on either work zone crash data analysis or work zone safety modeling were identified. The most relevant studies are specifically examined and discussed in the article. The identified studies were carefully synthesized to understand the state of knowledge on work zone safety. Agreement and inconsistency regarding the characteristics of the work zone crashes discussed in the descriptive studies were summarized. Progress and issues about the current practices on work zone crash frequency and severity modeling are also explored and discussed. The challenges facing work zone safety research are then presented. The synthesis of the literature suggests that the presence of a work zone is likely to increase the crash rate. Crashes are not uniformly distributed within work zones and rear-end crashes are the most prevalent type of crashes in work zones. There was no across-the-board agreement among numerous papers reviewed on the relationship between work zone crashes and other factors such as time, weather, victim severity, traffic control devices, and facility types. Moreover, both work zone crash frequency and severity models still rely on relatively simple modeling techniques and approaches. In addition, work zone data limitations have caused a number of challenges in analyzing and modeling work zone safety. Additional efforts on data collection, developing a systematic data analysis framework, and using more advanced modeling approaches are suggested as future research tasks.
A generalized nonlinear model-based mixed multinomial logit approach for crash data analysis.
Zeng, Ziqiang; Zhu, Wenbo; Ke, Ruimin; Ash, John; Wang, Yinhai; Xu, Jiuping; Xu, Xinxin
2017-02-01
The mixed multinomial logit (MNL) approach, which can account for unobserved heterogeneity, is a promising unordered model that has been employed in analyzing the effect of factors contributing to crash severity. However, its basic assumption of using a linear function to explore the relationship between the probability of crash severity and its contributing factors can be violated in reality. This paper develops a generalized nonlinear model-based mixed MNL approach which is capable of capturing non-monotonic relationships by developing nonlinear predictors for the contributing factors in the context of unobserved heterogeneity. The crash data on seven Interstate freeways in Washington between January 2011 and December 2014 are collected to develop the nonlinear predictors in the model. Thirteen contributing factors in terms of traffic characteristics, roadway geometric characteristics, and weather conditions are identified to have significant mixed (fixed or random) effects on the crash density in three crash severity levels: fatal, injury, and property damage only. The proposed model is compared with the standard mixed MNL model. The comparison results suggest a slight superiority of the new approach in terms of model fit measured by the Akaike Information Criterion (12.06 percent decrease) and Bayesian Information Criterion (9.11 percent decrease). The predicted crash densities for all three levels of crash severities of the new approach are also closer (on average) to the observations than the ones predicted by the standard mixed MNL model. Finally, the significance and impacts of the contributing factors are analyzed. Copyright © 2016 Elsevier Ltd. All rights reserved.
Xu, Chengcheng; Wang, Wei; Liu, Pan; Zhang, Fangwei
2015-01-01
This study aimed to identify the traffic flow variables contributing to crash risks under different traffic states and to develop a real-time crash risk model incorporating the varying crash mechanisms across different traffic states. The crash, traffic, and geometric data were collected on the I-880N freeway in California in 2008 and 2009. This study considered 4 different traffic states in Wu's 4-phase traffic theory. They are free fluid traffic, bunched fluid traffic, bunched congested traffic, and standing congested traffic. Several different statistical methods were used to accomplish the research objective. The preliminary analysis showed that traffic states significantly affected crash likelihood, collision type, and injury severity. Nonlinear canonical correlation analysis (NLCCA) was conducted to identify the underlying phenomena that made certain traffic states more hazardous than others. The results suggested that different traffic states were associated with various collision types and injury severities. The matching of traffic flow characteristics and crash characteristics in NLCCA revealed how traffic states affected traffic safety. The logistic regression analyses showed that the factors contributing to crash risks were quite different across various traffic states. To incorporate the varying crash mechanisms across different traffic states, random parameters logistic regression was used to develop a real-time crash risk model. Bayesian inference based on Markov chain Monte Carlo simulations was used for model estimation. The parameters of traffic flow variables in the model were allowed to vary across different traffic states. Compared with the standard logistic regression model, the proposed model significantly improved the goodness-of-fit and predictive performance. These results can promote a better understanding of the relationship between traffic flow characteristics and crash risks, which is valuable knowledge in the pursuit of improving traffic safety on freeways through the use of dynamic safety management systems.
Michigan fatal and serious injury traffic-crash patterns : 1993-1997
DOT National Transportation Integrated Search
1999-01-01
This report details facts and figures relevant to a better understanding of possible causes of and prevention implications for deaths and serious injuries due to traffic crashes in the state of Michigan during the period Junuary 1993 through December...
Michigan fatal and serious injury traffic-crash patterns : 1994-1998
DOT National Transportation Integrated Search
1999-11-01
This report details facts and figures relevant to a better understanding of possible causes of and prevention implications for deaths and serious injuries due to traffic crashes in the state of Michigan during the period January 1994 through December...
Safety evaluation of new roads.
DOT National Transportation Integrated Search
2002-09-01
The primary objective of this research study was to evaluate the crash history of bypass routes to determine if there were unusual patterns or changes in the crash history on these routes over the first years of operation. The focus of the evaluation...
Zou, Yaotian; Tarko, Andrew P
2018-02-01
The objective of this study was to develop crash modification factors (CMFs) and estimate the average crash costs applicable to a wide range of road-barrier scenarios that involved three types of road barriers (concrete barriers, W-beam guardrails, and high-tension cable barriers) to produce a suitable basis for comparing barrier-oriented design alternatives and road improvements. The intention was to perform the most comprehensive and in-depth analysis allowed by the cross-sectional method and the crash data available in Indiana. To accomplish this objective and to use the available data efficiently, the effects of barrier were estimated on the frequency of barrier-relevant (BR) crashes, the types of harmful events and their occurrence during a BR crash, and the severity of BR crash outcomes. The harmful events component added depth to the analysis by connecting the crash onset with its outcome. Further improvement of the analysis was accomplished by considering the crash outcome severity of all the individuals involved in a crash and not just drivers, utilizing hospital data, and pairing the observations with and without road barriers along same or similar road segments to better control the unobserved heterogeneity. This study confirmed that the total number of BR crashes tended to be higher where medians had installed barriers, mainly due to collisions with barriers and, in some cases, with other vehicles after redirecting vehicles back to traffic. These undesirable effects of barriers were surpassed by the positive results of reducing cross-median crashes, rollover events, and collisions with roadside hazards. The average cost of a crash (unit cost) was reduced by 50% with cable barriers installed in medians wider than 50ft. A similar effect was concluded for concrete barriers and guardrails installed in medians narrower than 50ft. The studied roadside guardrails also reduced the unit cost by 20%-30%. Median cable barriers were found to be the most effective among all the studied barriers due to the smaller increase in the crash frequency caused by these barriers and the less severe injury outcomes. More specifically, the occupants of vehicles colliding with near-side cable barriers tended to have less severe injuries than occupants of vehicles entering the median from median's farther side. The near-side cable barriers provided protection against rollover inside the median and against a potentially dangerous collision with or running over the median drain; therefore, the greatest safety benefit can be expected where cable barriers are installed at both edges of the median. The CMFs and unit crash costs for 48 road-barrier scenarios produced in this study are included in this paper. Copyright © 2017 Elsevier Ltd. All rights reserved.
Gender differences in injury severity risks in crashes at signalized intersections.
Obeng, K
2011-07-01
This paper analyzes gender differences in crash risk severities using data for signalized intersections. It estimates gender models for injury severity risks and finds that driver condition, type of crash, type of vehicle driven and vehicle safety features have different effects on females' and males' injury severity risks. Also, it finds some variables which are significantly related to females' injury severity risks but not males' and others which affect males' injury severity risks but not females'. It concludes that better and more in-depth information about gender differences in injury severity risks is gained by estimating separate models for females and males. Copyright © 2011 Elsevier Ltd. All rights reserved.
Costs of large truck- and bus-involved crashes.
DOT National Transportation Integrated Search
2000-12-01
This study provides comprehensive, economically sophisticated estimates of the costs of highway crashes involving large trucks and buses by severity. Based on the latest data available, the estimated cost of police-reported crashes involving trucks w...
Takahashi, Hiroki; Fujita, Takashi; Nakahara, Shinji; Sakamoto, Tetsuya
2018-04-19
This study describes injury patterns and outcomes related to the seating position of child passengers involved in motor vehicle crashes in Japan. Using data obtained from a national trauma registry database, we compared the occurrence of injuries by body parts, length of hospital stay and in-hospital deaths between front-seating and rear-seating among children. We analysed 166 children aged 0-5 years and 205 children aged 6-12 years. No significant differences were observed between front- and rear-seating for injured body parts, length of hospital stay or in-hospital deaths in the 0-5-year-old victims. Among those aged 6-12 years, rear-seating was associated with a higher incidence of head and chest injuries but the length of stay or in-hospital deaths did not differ. These findings contrast those of previous studies, which found that rear-seating reduces injury risk, possibly attributed to low age-appropriate restraint use among school-aged children in Japan.
A joint econometric analysis of seat belt use and crash-related injury severity.
Eluru, Naveen; Bhat, Chandra R
2007-09-01
This paper formulates a comprehensive econometric structure that recognizes two important issues in crash-related injury severity analysis. First, the impact of a factor on injury severity may be moderated by various observed and unobserved variables specific to an individual or to a crash. Second, seat belt use is likely to be endogenous to injury severity. That is, it is possible that intrinsically unsafe drivers do not wear seat belts and are the ones likely to be involved in high injury severity crashes because of their unsafe driving habits. The preceding issues are considered in the current research effort through the development of a comprehensive model of seat belt use and injury severity that takes the form of a joint correlated random coefficients binary-ordered response system. To our knowledge, this is the first instance of such a model formulation and application not only in the safety analysis literature, but in the econometrics literature in general. The empirical analysis is based on the 2003 General Estimates System (GES) data base. Several types of variables are considered to explain seat belt use and injury severity levels, including driver characteristics, vehicle characteristics, roadway design attributes, environmental factors, and crash characteristics. The results, in addition to confirming the effects of various explanatory variables, also highlight the importance of (a) considering the moderating effects of unobserved individual/crash-related factors on the determinants of injury severity and (b) seat belt use endogeneity. From a policy standpoint, the results suggest that seat belt non-users, when apprehended in the act, should perhaps be subjected to both a fine (to increase the chances that they wear seat belts) as well as mandatory enrollment in a defensive driving course (to attempt to change their aggressive driving behaviors).
Benefits of a Low Severity Frontal Crash Test
Digges, Kennerly; Dalmotas, Dainius
2007-01-01
The US Federal Motor Vehicle Safety Standard for frontal protection requires vehicle crash tests into a rigid barrier with two belted dummies in the front seats. The standard was recently modified to require two separate 56 Kph frontal tests. In one test the dummies are 50% males. In the other test, the dummies are 5% females. Analysis of crash test data indicates that the 56 Kph test does not encourage technology to reduce chest injuries in lower severity crashes. Tests conducted by Transport Canada provide data from belted 5% female dummies in the front seats of vehicles that were subjected crashes into a rigid barrier at 40 Kph. An analysis of the results showed that for many vehicles, the risks of serious chest injuries were higher in the 40 Kph test than in a 56 Kph test. This paper examines the benefits that would result from a requirement for a low severity (40 Kph) frontal barrier crash test with two belted 5% female dummies and more stringent chest injury requirements. A preliminary benefits analysis for chest deflection allowable in the range of 28 mm. to 36 mm. was conducted. A standard that limits the chest deflection to 34 mm. would reduce serious chest injury by 16% to 24% for the belted population in frontal crashes. PMID:18184499
Benefits of a low severity frontal crash test.
Digges, Kennerly; Dalmotas, Dainius
2007-01-01
The US Federal Motor Vehicle Safety Standard for frontal protection requires vehicle crash tests into a rigid barrier with two belted dummies in the front seats. The standard was recently modified to require two separate 56 Kph frontal tests. In one test the dummies are 50% males. In the other test, the dummies are 5% females. Analysis of crash test data indicates that the 56 Kph test does not encourage technology to reduce chest injuries in lower severity crashes. Tests conducted by Transport Canada provide data from belted 5% female dummies in the front seats of vehicles that were subjected crashes into a rigid barrier at 40 Kph. An analysis of the results showed that for many vehicles, the risks of serious chest injuries were higher in the 40 Kph test than in a 56 Kph test. This paper examines the benefits that would result from a requirement for a low severity (40 Kph) frontal barrier crash test with two belted 5% female dummies and more stringent chest injury requirements. A preliminary benefits analysis for chest deflection allowable in the range of 28 mm. to 36 mm. was conducted. A standard that limits the chest deflection to 34 mm. would reduce serious chest injury by 16% to 24% for the belted population in frontal crashes.
Evaluation of Vehicle-Based Crash Severity Metrics.
Tsoi, Ada H; Gabler, Hampton C
2015-01-01
Vehicle change in velocity (delta-v) is a widely used crash severity metric used to estimate occupant injury risk. Despite its widespread use, delta-v has several limitations. Of most concern, delta-v is a vehicle-based metric which does not consider the crash pulse or the performance of occupant restraints, e.g. seatbelts and airbags. Such criticisms have prompted the search for alternative impact severity metrics based upon vehicle kinematics. The purpose of this study was to assess the ability of the occupant impact velocity (OIV), acceleration severity index (ASI), vehicle pulse index (VPI), and maximum delta-v (delta-v) to predict serious injury in real world crashes. The study was based on the analysis of event data recorders (EDRs) downloaded from the National Automotive Sampling System / Crashworthiness Data System (NASS-CDS) 2000-2013 cases. All vehicles in the sample were GM passenger cars and light trucks involved in a frontal collision. Rollover crashes were excluded. Vehicles were restricted to single-event crashes that caused an airbag deployment. All EDR data were checked for a successful, completed recording of the event and that the crash pulse was complete. The maximum abbreviated injury scale (MAIS) was used to describe occupant injury outcome. Drivers were categorized into either non-seriously injured group (MAIS2-) or seriously injured group (MAIS3+), based on the severity of any injuries to the thorax, abdomen, and spine. ASI and OIV were calculated according to the Manual for Assessing Safety Hardware. VPI was calculated according to ISO/TR 12353-3, with vehicle-specific parameters determined from U.S. New Car Assessment Program crash tests. Using binary logistic regression, the cumulative probability of injury risk was determined for each metric and assessed for statistical significance, goodness-of-fit, and prediction accuracy. The dataset included 102,744 vehicles. A Wald chi-square test showed each vehicle-based crash severity metric estimate to be a significant predictor in the model (p < 0.05). For the belted drivers, both OIV and VPI were significantly better predictors of serious injury than delta-v (p < 0.05). For the unbelted drivers, there was no statistically significant difference between delta-v, OIV, VPI, and ASI. The broad findings of this study suggest it is feasible to improve injury prediction if we consider adding restraint performance to classic measures, e.g. delta-v. Applications, such as advanced automatic crash notification, should consider the use of different metrics for belted versus unbelted occupants.
The influence of daily sleep patterns of commercial truck drivers on driving performance
Chen, Guang Xiang; Fang, Youjia; Guo, Feng; Hanowski, Richard J.
2016-01-01
Fatigued and drowsy driving has been found to be a major cause of truck crashes. Lack of sleep is the number one cause of fatigue and drowsiness. However, there are limited data on the sleep patterns (sleep duration, sleep percentage in the duration of non-work period, and the time when sleep occurred) of truck drivers in non-work periods and the impact on driving performance. This paper examined sleep patterns of 96 commercial truck drivers during non-work periods and evaluated the influence these sleep patterns had on truck driving performance. Data were from the Naturalistic Truck Driving Study. Each driver participated in the study for approximately four weeks. A shift was defined as a non-work period followed by a work period. A total of 1397 shifts were identified. Four distinct sleep patterns were identified based on sleep duration, sleep start/end point in a non-work period, and the percentage of sleep with reference to the duration of non-work period. Driving performance was measured by safety-critical events, which included crashes, near-crashes, crash-relevant conflicts, and unintentional lane deviations. Negative binomial regression was used to evaluate the association between the sleep patterns and driving performance, adjusted for driver demographic information. The results showed that the sleep pattern with the highest safety-critical event rate was associated with shorter sleep, sleep in the early stage of a non-work period, and less sleep between 1 a.m. and 5 a.m. This study also found that male drivers, with fewer years of commercial vehicle driving experience and higher body mass index, were associated with deteriorated driving performance and increased driving risk. The results of this study could inform hours-of-service policy-making and benefit safety management in the trucking industry. PMID:26954762
Contributing factors to vehicle to vehicle crash frequency and severity under rainfall.
Jung, Soyoung; Jang, Kitae; Yoon, Yoonjin; Kang, Sanghyeok
2014-09-01
This study combined vehicle to vehicle crash frequency and severity estimations to examine factor impacts on Wisconsin highway safety in rainy weather. Because of data deficiency, the real-time water film depth, the car-following distance, and the vertical curve grade were estimated with available data sources and a GIS analysis to capture rainy weather conditions at the crash location and time. Using a negative binomial regression for crash frequency estimation, the average annual daily traffic per lane, the interaction between the posted speed limit change and the existence of an off-ramp, and the interaction between the travel lane number change and the pavement surface material change were found to increase the likelihood of vehicle to vehicle crashes under rainfall. However, more average daily rainfall per month and a wider left shoulder were identified as factors that decrease the likelihood of vehicle to vehicle crashes. In the crash severity estimation using the multinomial logit model that outperformed the ordered logit model, the travel lane number, the interaction between the travel lane number and the slow grade, the deep water film, and the rear-end collision type were more likely to increase the likelihood of injury crashes under rainfall compared with crashes involving only property damage. As an exploratory data analysis, this study provides insight into potential strategies for rainy weather highway safety improvement, specifically, the following weather-sensitive strategies: road design and ITS implementation for drivers' safety awareness under rainfall. Copyright © 2014 National Safety Council and Elsevier Ltd. All rights reserved.
Goldenbeld, Charles; Reurings, Martine; Van Norden, Yvette; Stipdonk, Henk
2013-01-01
To establish the statistical relationship between offenses and crashes when the unit of analysis is the vehicle instead of the driver, to show the influence of the severity (e.g., minor speed offenses) on this relationship, and to research whether the form of this relationship is similar in different enforcement contexts. An exploratory analysis was conducted using Dutch traffic offense and crash data. Crash data included all police-registered crashes involving motorized and registered vehicles in 2009; offense data included all non-criminal traffic offenses registered during 2005-2009 (mostly camera detected). Together these comprise an estimated 97 percent of all traffic offenses registered in this period. The analysis was done on a level of identified vehicles rather than persons. Vehicles involved in crashes were matched to vehicles involved in traffic offenses. The offense frequency distributions of registered crash involved vehicles and a random selection of vehicles was analyzed. Two comparisons were made: (1) privately owned vehicles versus company-owned vehicles and (2) vehicles for which only minor speed offenses were registered versus vehicles for which at least one major speed offense was registered. An increase in traffic offense frequency coincides with a stronger increase in relative crash involvement. This relationship was adequately described by a power function. The slightly more than linear increase in the crash risk for vehicles with only minor speed offenses suggests that minor speed offenses (<10 km/h over the limit) contributed slightly to crashes. This relationship was unlikely to be caused by increased distance traveled only. For vehicles with at least one or more major speed violation an approximately quadratic increase of crash risk with increasing speed offense frequency was found. A comparison of Dutch and Canadian data showed a much more progressive offense-crash relationship in the Dutch data. The crash involvement of vehicles increased more than linearly with the number of minor traffic violations. Thus, automatic detection of minor offenses bears relevance to safety. The substantial increase in crash rates with speed offense frequency for vehicles with at least one major speed violation suggests that these vehicles represent a specific group with a significantly increased crash risk, especially in the case of many minor offenses. The more progressive relationship between offenses and crashes in The Netherlands when compared to Canada was hypothesized to result from the higher intensity camera enforcement levels and less severe consequences in the Dutch enforcement and adjudication system.
Røe, Cecilie; Skandsen, Toril; Manskow, Unn; Ader, Tiina; Anke, Audny
2015-01-01
The aim of the present study was to evaluate mortality and functional outcome in old and very old patients with severe traumatic brain injury (TBI) and compare to the predicted outcome according to the internet based CRASH (Corticosteroid Randomization After Significant Head injury) model based prediction, from the Medical Research Council (MRC). Methods. Prospective, national multicenter study including patients with severe TBI ≥65 years. Predicted mortality and outcome were calculated based on clinical information (CRASH basic) (age, GCS score, and pupil reactivity to light), as well as with additional CT findings (CRASH CT). Observed 14-day mortality and favorable/unfavorable outcome according to the Glasgow Outcome Scale at one year was compared to the predicted outcome according to the CRASH models. Results. 97 patients, mean age 75 (SD 7) years, 64% men, were included. Two patients were lost to follow-up; 48 died within 14 days. The predicted versus the observed odds ratio (OR) for mortality was 2.65. Unfavorable outcome (GOSE < 5) was observed at one year follow-up in 72% of patients. The CRASH models predicted unfavorable outcome in all patients. Conclusion. The CRASH model overestimated mortality and unfavorable outcome in old and very old Norwegian patients with severe TBI. PMID:26688614
The effect of frontal air bags on eye injury patterns in automobile crashes.
Duma, Stefan M; Jernigan, M Virginia; Stitzel, Joel D; Herring, Ian P; Crowley, John S; Brozoski, Fred T; Bass, Cameron R
2002-11-01
To investigate eye injuries resulting from frontal automobile crashes and to determine the effects of frontal air bags. The National Automotive Sampling System database files from January 1, 1993, through December 31, 1999, were examined in a 3-part study that included an investigation of 22 236 individual crashes that occurred in the United States. A new 4-level eye injury severity scale that quantifies injuries based on recovery time, need for surgery, and possible loss of sight was developed. Of all occupants who were exposed to an air bag deployment, 3% sustained an eye injury. In contrast, 2% of occupants not exposed to an air bag deployment sustained an eye injury. A closer examination of the type of eye injuries showed that there was a statistically significant increase in the risk of corneal abrasions for occupants who were exposed to an air bag compared with those who were not (P =.03). Of occupants exposed to an air bag deployment, 0.5% sustained a corneal abrasion compared with 0.04% of occupants who were not exposed to an air bag. Using the new injury levels, it was shown that although occupants exposed to an air bag deployment had a higher risk of sustaining minor eye injuries, the air bag appears to have provided a beneficial exchange by reducing the number of severe eye injuries.
NASA Astrophysics Data System (ADS)
Ko, Bonggyun; Song, Jae Wook; Chang, Woojin
2018-02-01
The aim of this research is to propose an alarm index to forecast the crash of the Korean financial market in extension to the idea of Johansen-Ledoit-Sornette model, which uses the log-periodic functions and pattern recognition algorithm. We discover that the crashes of the Korean financial market can be classified into domestic and global crises where each category requires different window length of fitted datasets. Therefore, we add the window length as a new parameter to enhance the performance of alarm index. Distinguishing the domestic and global crises separately, our alarm index demonstrates more robust forecasting than previous model by showing the error diagram and the results of trading performance.
Speed enforcement program guidelines
DOT National Transportation Integrated Search
2008-03-01
It is well-established that speeding represents a risk to public safety. Excessive speed increases the likelihood of crashing and the risk of severe injury in a crash. In 2005, more than 13,000 lives were lost in speeding-related crashes. Reducing sp...
Pedestrian and bicyclist fatalities in large truck crashes, 2013.
DOT National Transportation Integrated Search
2016-05-01
This report presents data on pedestrian and bicyclist fatalities in large truck crashes over the past several years (up to 2013). Information is provided on the characteristics of fatal crashes recorded in the National Highway Traffic Safety Administ...
Chen, Cong; Zhang, Guohui; Yang, Jinfu; Milton, John C; Alcántara, Adélamar Dely
2016-05-01
Rear-end crashes are a major type of traffic crashes in the U.S. Of practical necessity is a comprehensive examination of its mechanism that results in injuries and fatalities. Decision table (DT) and Naïve Bayes (NB) methods have both been used widely but separately for solving classification problems in multiple areas except for traffic safety research. Based on a two-year rear-end crash dataset, this paper applies a decision table/Naïve Bayes (DTNB) hybrid classifier to select the deterministic attributes and predict driver injury outcomes in rear-end crashes. The test results show that the hybrid classifier performs reasonably well, which was indicated by several performance evaluation measurements, such as accuracy, F-measure, ROC, and AUC. Fifteen significant attributes were found to be significant in predicting driver injury severities, including weather, lighting conditions, road geometry characteristics, driver behavior information, etc. The extracted decision rules demonstrate that heavy vehicle involvement, a comfortable traffic environment, inferior lighting conditions, two-lane rural roadways, vehicle disabled damage, and two-vehicle crashes would increase the likelihood of drivers sustaining fatal injuries. The research limitations on data size, data structure, and result presentation are also summarized. The applied methodology and estimation results provide insights for developing effective countermeasures to alleviate rear-end crash injury severities and improve traffic system safety performance. Copyright © 2016 Elsevier Ltd. All rights reserved.
The injury epidemiology of cyclists based on a road trauma registry.
Amoros, Emmanuelle; Chiron, Mireille; Thélot, Bertrand; Laumon, Bernard
2011-08-17
Bicycle use has increased in some of France's major cities, mainly as a means of transport. Bicycle crashes need to be studied, preferably by type of cycling. Here we conduct a descriptive analysis. A road trauma registry has been in use in France since 1996, in a large county around Lyon (the Rhône, population 1.6 million). It covers outpatients, inpatients and fatalities. All injuries are coded using the Abbreviated Injury Scale (AIS). Proxies were used to identify three types of cycling: learning = children (0-10 years old); sports cycling = teenagers and adults injured outside towns; cycling as means of transport = teenagers and adults injured in towns. The study is based on 13,684 cyclist casualties (1996-2008). The percentage of cyclists injured in a collision with a motor vehicle was 8% among children, 17% among teenagers and adults injured outside towns, and 31% among those injured in towns. The percentage of serious casualties (MAIS 3+) was 4.5% among children, 10.9% among adults injured outside towns and 7.2% among those injured in towns. Collisions with motor-vehicles lead to more internal injuries than bicycle-only crashes. The description indicates that cyclist type is associated with different crash and injury patterns. In particular, cyclists injured in towns (where cycling is increasing) are generally less severely injured than those injured outside towns for both types of crash (bicycle-only crashes and collisions with a motor vehicle). This is probably due to lower speeds in towns, for both cyclists and motor vehicles.
The injury epidemiology of cyclists based on a road trauma registry
2011-01-01
Background Bicycle use has increased in some of France's major cities, mainly as a means of transport. Bicycle crashes need to be studied, preferably by type of cycling. Here we conduct a descriptive analysis. Method A road trauma registry has been in use in France since 1996, in a large county around Lyon (the Rhône, population 1.6 million). It covers outpatients, inpatients and fatalities. All injuries are coded using the Abbreviated Injury Scale (AIS). Proxies were used to identify three types of cycling: learning = children (0-10 years old); sports cycling = teenagers and adults injured outside towns; cycling as means of transport = teenagers and adults injured in towns. The study is based on 13,684 cyclist casualties (1996-2008). Results The percentage of cyclists injured in a collision with a motor vehicle was 8% among children, 17% among teenagers and adults injured outside towns, and 31% among those injured in towns. The percentage of serious casualties (MAIS 3+) was 4.5% among children, 10.9% among adults injured outside towns and 7.2% among those injured in towns. Collisions with motor-vehicles lead to more internal injuries than bicycle-only crashes. Conclusion The description indicates that cyclist type is associated with different crash and injury patterns. In particular, cyclists injured in towns (where cycling is increasing) are generally less severely injured than those injured outside towns for both types of crash (bicycle-only crashes and collisions with a motor vehicle). This is probably due to lower speeds in towns, for both cyclists and motor vehicles. PMID:21849071
Mechanisms of cervical spine injuries for non-fatal motorcycle road crash.
Ooi, S S; Wong, S V; Radin Umar, R S; Azhar, A A; Yeap, J S; Megat Ahmad, M M H
2004-06-01
Cervical spine injuries such as subluxation and fracture dislocation have long been known to result in severe consequences, as well as the trauma management itself. The injury to the region has been identified as one of the major causes of death in Malaysian motorcyclists involved in road crashes, besides head and chest injuries (Pang, 1999). Despite this, cervical spine injury in motorcyclists is not a well-studied injury, unlike the whiplash injury in motorcar accidents. The present study is a retrospective study on the mechanisms of injury in cervical spine sustained by Malaysian motorcyclists, who were involved in road crash using an established mechanistic classification system. This will serve as an initial step to look at the cervical injuries pattern. The information obtained gives engineer ideas to facilitate design and safety features to reduce injuries. All cervical spine injured motorcyclists admitted to Hospital Kuala Lumpur between January 1, 2000 and December 31, 2001 were included in the present study. Based on the medical notes and radiological investigations (X-rays, CT and MRI scans), the mechanisms of injuries were formulated using the injury mechanics classification. The result shows that flexion of the cervical vertebrae is the most common vertebral kinematics in causing injury to motorcyclists. This indicates that the cervical vertebrae sustained a high-energy loading at flexion movement in road crash, and exceeded its tolerance level. The high frequency of injury at the C5 vertebra, C6 vertebra and C5-C6 intervertebral space are recorded. Classification based on the Abbreviated Injury Scale (AIS) is made to give a view on injury severity, 9.1% of the study samples have been classified as AIS code 1, 51.5% with AIS 2 and 21.2% with AIS 3.
Huisingh, Carrie; Levitan, Emily B.; Irvin, Marguerite R.; MacLennan, Paul; Wadley, Virginia; Owsley, Cynthia
2017-01-01
Purpose An innovative methodology using naturalistic driving data was used to examine the association between visual sensory and visual-cognitive function and rates of future crash or near-crash involvement among older drivers. Methods The Strategic Highway Research Program (SHRP2) Naturalistic Driving Study was used for this prospective analysis. The sample consisted of N = 659 drivers aged ≥70 years and study participation lasted 1 or 2 years for most participants. Distance and near visual acuity, contrast sensitivity, peripheral vision, visual processing speed, and visuospatial skills were assessed at baseline. Crash and near-crash involvement were based on video recordings and vehicle sensors. Poisson regression models were used to generate crude and adjusted rate ratios (RRs) and 95% confidence intervals, while accounting for person-miles of travel. Results After adjustment, severe impairment of the useful field of view (RR = 1.33) was associated with an increased rate of near-crash involvement. Crash, severe crash, and at-fault crash involvement were associated with impaired contrast sensitivity in the worse eye (RRs = 1.38, 1.54, and 1.44, respectively) and far peripheral field loss in both eyes (RRs = 1.74, 2.32, and 1.73, respectively). Conclusions Naturalistic driving data suggest that contrast sensitivity in the worse eye and far peripheral field loss in both eyes elevate the rates of crash involvement, and impaired visual processing speed elevates rates of near-crash involvement among older drivers. Naturalistic driving data may ultimately be critical for understanding the relationship between vision and driving safety. PMID:28605807
Ferguson, Susan A
2007-12-01
Electronic stability control (ESC) is designed to help drivers maintain heading control of their vehicles in high-speed or sudden maneuvers and on slippery roads. The wider proliferation of ESC across the vehicle fleet has allowed evaluation of its effects in real-world crashes in many countries, including Japan, Germany, Sweden, France, Great Britain, and the United States. This article provides a summary of the findings. Studies that examined the real-world effectiveness of ESC were reviewed. Crash effects have been examined for different roadways, using differing analytic methods, different crash severities, and different make/model vehicles including both cars and SUVs. The review discusses the methodological differences and examines the findings according to vehicle type, crash type and severity, and road conditions. The overwhelming majority of studies find that ESC is highly effective in reducing single-vehicle crashes in cars and SUVs. Fatal single-vehicle crashes involving cars are reduced by about 30-50% and SUVs by 50-70%. Fatal rollover crashes are estimated to be about 70-90% lower with ESC regardless of vehicle type. A number of studies find improved effectiveness in reducing crashes when road conditions are slippery. There is little or no effect of ESC in all multi-vehicle crashes; however, there is a 17-38% reduction in more serious, fatal multi-vehicle crashes. Given the extraordinary benefits of ESC in preventing crashes, especially those with more serious outcomes, the implementation of ESC should be accelerated to cover the full range of passenger vehicles in both developed and developing markets.
Torres, Pedro; Romano, Eduardo; Voas, Robert B.; de la Rosa, Mario; Lacey, John H.
2014-01-01
Introduction The literature presents a puzzling picture of Latinos being overrepresented in alcohol-related crashes, but not in noncrash drinking and driving. This report examines if, like other demographic variables in which some groups are at a higher crash risk than others (e.g., young drivers), different racial/ethnic groups face different crash risks Method This study compares blood-alcohol information from the 2006–2007 U.S. Fatality Analysis Reporting System (FARS) with control data from the 2007 U.S. National Roadside Survey. Logistic regression, including a dual interaction between BAC and race/ethnicity, was used to estimate crash risk at different BAC levels. Results It was found that, although Hispanic and African-American drivers were less likely to be involved in single-vehicle crashes than their White counterparts, all drivers face similar BAC relative crash risk regardless of their group membership. The overrepresentation of Latino drivers in alcohol-related crashes could be explained by differences in patterns of consumption, driving exposure, lack of awareness of driving rules, and/or socioeconomics. PMID:24529097
Simulation of the right-angle car collision based on identified parameters
NASA Astrophysics Data System (ADS)
Kostek, R.; Aleksandrowicz, P.
2017-10-01
This article presents an influence of contact parameters on the collision pattern of vehicles. In this case a crash of two Fiat Cinquecentos with perpendicular median planes was simulated. The first vehicle was driven with a speed 50 km/h and crashed into the other one, standing still. It is a typical collision at junctions. For the first simulation, the default parameters of the V-SIM simulation program were assumed and then the parameters identified from the crash test of a Fiat Cinquecento, published by ADAC (Allgemeiner Deutscher Automobil-Club) were used. Various post-impact movements were observed for both simulations, which demonstrates a sensitivity of the simulation results to the assumed parameters. Applying the default parameters offered by the program can lead to inadequate evaluation of the collision part due to its only approximate reconstruction, which in consequence, influences the court decision. It was demonstrated how complex it is to reconstruct the pattern of the vehicles’ crash and what problems are faced by expert witnesses who tend to use default parameters.
Venkataraman, Narayan; Ulfarsson, Gudmundur F; Shankar, Venky N
2013-10-01
A nine-year (1999-2007) continuous panel of crash histories on interstates in Washington State, USA, was used to estimate random parameter negative binomial (RPNB) models for various aggregations of crashes. A total of 21 different models were assessed in terms of four ways to aggregate crashes, by: (a) severity, (b) number of vehicles involved, (c) crash type, and by (d) location characteristics. The models within these aggregations include specifications for all severities (property damage only, possible injury, evident injury, disabling injury, and fatality), number of vehicles involved (one-vehicle to five-or-more-vehicle), crash type (sideswipe, same direction, overturn, head-on, fixed object, rear-end, and other), and location types (urban interchange, rural interchange, urban non-interchange, rural non-interchange). A total of 1153 directional road segments comprising of the seven Washington State interstates were analyzed, yielding statistical models of crash frequency based on 10,377 observations. These results suggest that in general there was a significant improvement in log-likelihood when using RPNB compared to a fixed parameter negative binomial baseline model. Heterogeneity effects are most noticeable for lighting type, road curvature, and traffic volume (ADT). Median lighting or right-side lighting are linked to increased crash frequencies in many models for more than half of the road segments compared to both-sides lighting. Both-sides lighting thereby appears to generally lead to a safety improvement. Traffic volume has a random parameter but the effect is always toward increasing crash frequencies as expected. However that the effect is random shows that the effect of traffic volume on crash frequency is complex and varies by road segment. The number of lanes has a random parameter effect only in the interchange type models. The results show that road segment-specific insights into crash frequency occurrence can lead to improved design policy and project prioritization. Copyright © 2013 Elsevier Ltd. All rights reserved.
Yunus, Siti Salmiah Mohd; Ngeow, Wei Cheong; Ramli, Roszalina
2015-09-01
A cross-sectional study to determine the pattern of craniomaxillofacial (CMF) injuries among children involved in road traffic crashes was performed. The association of protective equipment use with the CMF injuries was evaluated. Retrospective records of children treated in the University Malaya Medical Centre, Kuala Lumpur, Malaysia, after road traffic crashes between January 1, 2008 and December 31, 2012 were reviewed, and, after that, telephone interviews were made. Seventy-one children were included in this study. Fifty-two (73.6%) were involved in a motorcycle injury and 19 (23.4%) in a car crash. Their mean age was 6.02 years; SD, 3.46 (range between 0 to 13 years old). More male children were observed (52.1%) compared with females (47.9%). Thirty-nine point four percent of the children sustained CMF injuries, 33.8% body injuries, and 23.9% had both CMF and other body parts injuries. The highest injury severity score was 26, whereas the lowest was 0. Many children did not use protective equipment during traveling, 44.2% of children among motorcycle pillion riders, and 78.9% among car passengers. The association between helmet use and CMF injuries was shown to be statistically significant (P < .001). Craniomaxillofacial injuries could be prevented with the use of motorcycle helmet and seat belt. Copyright © 2015 Elsevier Inc. All rights reserved.
Population density and mortality among individuals in motor vehicle crashes.
Gedeborg, Rolf; Thiblin, Ingemar; Byberg, Liisa; Melhus, Håkan; Lindbäck, Johan; Michaelsson, Karl
2010-10-01
To assess whether higher mortality rates among individuals in motor vehicle crashes in areas with low population density depend on injury type and severity or are related to the performance of emergency medical services (EMS). Prehospital and hospital deaths were studied in a population-based cohort of 41,243 motor vehicle crashes that occurred in Sweden between 1998 and 2004. The final multivariable analysis was restricted to 6884 individuals in motor vehicle crashes, to minimise the effects of confounding factors. Crude mortality rates following motor vehicle crashes were inversely related to regional population density. In regions with low population density, the unadjusted rate ratio for prehospital death was 2.2 (95% CI 1.9 to 2.5) and for hospital death 1.5 (95% CI 1.1 to 1.9), compared with a high-density population. However, after controlling for regional differences in age, gender and the type/severity of injuries among 6884 individuals in motor vehicle crashes, low population density was no longer associated with increased mortality. At 25 years of age, predicted prehospital mortality was 9% lower (95% CI 5% to 12%) in regions with low population density compared with high population density. This difference decreased with increasing age, but was still 3% lower (95% CI 0.5% to 5%) at 65 years of age. The inverse relationship between population density and mortality among individuals in motor vehicle crashes is related to pre-crash factors that influence the type and severity of injuries and not to differences in EMS.
Bennett, Tellen D; Kaufman, Robert; Schiff, Melissa; Mock, Charles; Quan, Linda
2006-09-01
The mechanism, crash characteristics, and spectrum of lower extremity injuries in children restrained in forward-facing car seats during front and rear impacts have not been described. We identified in two databases children who sustained lower extremity injuries while restrained in forward-facing car seats. To identify the mechanism, we analyzed crash reconstructions from three frontal-impact cases from the Crash Injury Research and Engineering Network. To further describe the crash and injury characteristics we evaluated children between 1 and 4 years of age with lower extremity injuries from front or rear impacts in the National Automotive Sampling System (NASS) Crashworthiness Data System (CDS) database. Crash reconstruction data demonstrated that the likely mechanism of lower extremity injury was contact between the legs and the front seatbacks. In the CDS database, we identified 15 children with lower extremity injuries in a forward-facing child seat, usually (13 out of 15) placed in the rear seat, incurred in frontal impacts (11 out of 15). Several (5 out of 15) children were in unbelted or improperly secured forward-facing car seats. Injury Severity Scores varied widely (5-50). Children in forward-facing car seats involved in severe front or rear crashes may incur a range of lower extremity injury from impact with the car interior component in front of them. Crash scene photography can provide useful information about anatomic sites at risk for injury and alert emergency department providers to possible subtle injury.
Unit costs of medium and heavy truck crashes.
DOT National Transportation Integrated Search
2008-03-01
This study provides the latest estimates of unit costs for highway crashes involving medium/heavy trucks by severity. Based on the latest data available, the estimated cost of police-reported crashes involving trucks with a gross weight rating of mor...
Development of procedures for identifying high-crash locations and prioritizing safety improvements
DOT National Transportation Integrated Search
2003-06-01
The objectives of this study were to review and analyze the current procedures for identifying high-crash locations and evaluating and prioritizing roadway safety improvements at high-crash locations, and to recommend improved methods. Several tasks ...
Development of procedures for identifying high-crash locations and prioritizing safety improvements.
DOT National Transportation Integrated Search
2003-06-01
The objectives of this study were to review and analyze the current procedures for identifying high-crash locations and evaluating and prioritizing roadway safety improvements at high-crash locations, and to recommend improved methods. Several tasks ...
Effects of blind spot monitoring systems on police-reported lane-change crashes.
Cicchino, Jessica B
2018-06-21
To examine the effectiveness of blind spot monitoring systems in preventing police-reported lane-change crashes. Poisson regression was used to compare crash involvement rates per insured vehicle year in police-reported lane-change crashes in 26 U.S. states during 2009-2015 between vehicles with blind spot monitoring and the same vehicle models without the optional system, controlling for other factors that can affect crash risk. Crash involvement rates in lane-change crashes were 14% lower (95% confidence limits -24% to -2%) among vehicles with blind spot monitoring than those without. Blind spot monitoring systems are effective in preventing police-reported lane-change crashes when considering crashes of all severities. If every U.S. vehicle in 2015 were equipped with blind spot monitoring that performed like the study systems, it is estimated that about 50,000 crashes could have been prevented.
Hanna, Christina L; Hasselberg, Marie; Laflamme, Lucie; Möller, Jette
2010-01-14
Young car drivers run a higher risk of road traffic crash and injury not only because of their lack of experience but also because of their young age and their greater propensity for adopting unsafe driving practices. Also, low family socioeconomic position increases the risk of crash and of severe crash in particular. Whether this holds true for young unlicensed drivers as well is not known. Increasing attention is being drawn to the prevalence and practice of unlicensed driving among young people as an important contributor to road traffic fatalities. This is a population-based cohort study linking Swedish national register data for a cohort of 1 616 621 individuals born between 1977 and 1991. Crash circumstances for first-time road traffic crash (RTC) were compared considering licensed and unlicensed drivers. The socioeconomic distribution of injury was assessed considering household socioeconomic position, social welfare benefits, and level of urbanicity of the living area. The main outcome measure is relative risk of RTC. RTCs involving unlicensed drivers were over-represented among male drivers, suspected impaired drivers, severe injuries, crashes occurring in higher speed limit areas, and in fair road conditions. Unlicensed drivers from families in a lower socioeconomic position showed increased relative risks for RTC in the range of 1.75 to 3.25. Those living in rural areas had an increased relative risk for a severe RTC of 3.29 (95% CI 2.47 - 4.39) compared to those living in metropolitan areas. At the time of the crash, young unlicensed drivers display more risky driving practices than their licensed counterparts. Just as licensed drivers, unlicensed young people from low socioeconomic positions are over-represented in the most severe injury crashes. Whether the mechanisms lying behind those similarities compare between these groups remains to be determined.
Xie, Meiquan; Cheng, Wen; Gill, Gurdiljot Singh; Zhou, Jiao; Jia, Xudong; Choi, Simon
2018-02-17
Most of the extensive research dedicated to identifying the influential factors of hit-and-run (HR) crashes has utilized typical maximum likelihood estimation binary logit models, and none have employed real-time traffic data. To fill this gap, this study focused on investigating factors contributing to HR crashes, as well as the severity levels of HR. This study analyzed 4-year crash and real-time loop detector data by employing hierarchical Bayesian models with random effects within a sequential logit structure. In addition to evaluation of the impact of random effects on model fitness and complexity, the prediction capability of the models was examined. Stepwise incremental sensitivity and specificity were calculated and receiver operating characteristic (ROC) curves were utilized to graphically illustrate the predictive performance of the model. Among the real-time flow variables, the average occupancy and speed from the upstream detector were observed to be positively correlated with HR crash possibility. The average upstream speed and speed difference between upstream and downstream speeds were correlated with the occurrence of severe HR crashes. In addition to real-time factors, other variables found influential for HR and severe HR crashes were length of segment, adverse weather conditions, dark lighting conditions with malfunctioning street lights, driving under the influence of alcohol, width of inner shoulder, and nighttime. This study suggests the potential traffic conditions of HR and severe HR occurrence, which refer to relatively congested upstream traffic conditions with high upstream speed and significant speed deviations on long segments. The above findings suggest that traffic enforcement should be directed toward mitigating risky driving under the aforementioned traffic conditions. Moreover, enforcement agencies may employ alcohol checkpoints to counter driving under the influence (DUI) at night. With regard to engineering improvements, wider inner shoulders may be constructed to potentially reduce HR cases and street lights should be installed and maintained in working condition to make roads less prone to such crashes.
Evaluation of safety and mobility of two-lane roundabouts : final report.
DOT National Transportation Integrated Search
2017-07-01
When looking at measures of fatal and severe-injury crashes, roundabouts have demonstrated improved safety performance compared to traditional signalized intersections. Despite this, when it comes to less severe crashes, multilane roundabouts fail to...
Seacrist, Thomas; Belwadi, Aditya; Prabahar, Abhiti; Chamberlain, Samuel; Megariotis, James; Loeb, Helen
2016-09-01
Motor vehicle crashes are the leading cause of death for teens. Previous teen and adult crash rates have been based upon fatal crashes, police-reported crashes, and estimated miles driven. Large-scale naturalistic driving studies offer the opportunity to compute crash rates using a reliable methodology to capture crashes and driving exposure. The Strategic Highway Research Program 2 (SHRP2) Naturalistic Driving Study contains extensive real-world data on teen and adult driving. This article presents findings on the crash rates of novice teen and experienced adult drivers in naturalistic crashes. A subset from the SHRP2 database consisting of 539 crash events for novice teens (16-19 years, n = 549) and experienced adults (35-54 years, n = 591) was used. Onboard instrumentation such as scene cameras, accelerometers, and Global Positioning System logged time series data at 10 Hz. Scene videos were reviewed for all events to identify rear-end striking crashes. Dynamic variables such as acceleration and velocity were analyzed for rear-end striking events. Number of crashes, crash rates, rear-end striking crash severity, and rear-end striking impact velocity were compared between novice teens and experienced adults. Video review of the SHRP2 crashes identified significantly more crashes (P < 0.01) and rear-end striking crashes (P < 0.01) among the teen group than among the adult group. This yielded crash rates of 30.0 crashes per million miles driven for novice teens compared to 5.3 crashes per million miles driven for experienced adults. The crash rate ratio for teens vs. adults was 5.7. The rear-end striking crash rate was 13.5 and 1.8 per million miles driven for novice teens and experienced adults, respectively. The rear-end striking crash rate ratio for teens vs. adults was 7.5. The rear-end striking crash severity measured by the accelerometers was greater (P < 0.05) for the teen group (1.8 ± 0.9 g; median = 1.6 g) than for the adult group (1.1 ± 0.4 g; median = 1.0 g), suggesting that teen crashes tend to be more serious than adult crashes. Increased rear-end striking impact velocity (P < 0.01) was also observed for novice teens (18.8 ± 13.2 mph; median = 18.9 mph) compared to experienced adults (3.3 ± 1.2 mph; median = 2.8 mph). To our knowledge, this is the first study to compare crash rates between teens and adults using a large-scale naturalistic driving database. Unlike previous crash rates, the reported rates reliably control for crash type and driving exposure. These results conform to previous findings that novice teens exhibit increased crash rates compared to experienced adults.
Monaco, Kristen; Redmon, Brydey
2012-03-01
Using data from the Motor Carrier Management Information System, we model crashes as a function of firm characteristics, with a focus on the employment relationship. We find that very small firms (one driver, one truck) and firms that contract with owner operators have fewer crashes than employee-only companies, once other firm characteristics and exposure are controlled. Additionally, though very small firms are more likely to have severe crashes, we find no relationship between the share of owner operators and crash severity. Copyright © 2011 Elsevier Ltd. All rights reserved.
Analysis of roadway departure crashes on two-lane rural roads in Texas.
DOT National Transportation Integrated Search
2011-12-01
"This three-year research effort was undertaken to identify factors that influence the number and severity of : roadway departure crashes on rural two-lane highways in Texas and provide engineering countermeasures to : reduce this type of crash. The ...
Analysis of roadway departure crashes on two lane rural roads in Texas.
DOT National Transportation Integrated Search
2011-12-01
This three-year research effort was undertaken to identify factors that influence the number and severity of : roadway departure crashes on rural two-lane highways in Texas and provide engineering countermeasures to : reduce this type of crash. The s...
Revised costs of large truck-and bus-involved crashes.
DOT National Transportation Integrated Search
2002-11-01
This study provides the latest estimates of the costs of highway crashes involving large trucks and buses by severity. Based on the latest data available, the estimated cost of police-reported crashes involving trucks with a gross weight rating of mo...
Wu, Qiong; Zhang, Guohui; Ci, Yusheng; Wu, Lina; Tarefder, Rafiqul A; Alcántara, Adélamar Dely
2016-05-18
Teenage drivers are more likely to be involved in severely incapacitating and fatal crashes compared to adult drivers. Moreover, because two thirds of urban vehicle miles traveled are on signal-controlled roadways, significant research efforts are needed to investigate intersection-related teenage driver injury severities and their contributing factors in terms of driver behavior, vehicle-infrastructure interactions, environmental characteristics, roadway geometric features, and traffic compositions. Therefore, this study aims to explore the characteristic differences between teenage and adult drivers in intersection-related crashes, identify the significant contributing attributes, and analyze their impacts on driver injury severities. Using crash data collected in New Mexico from 2010 to 2011, 2 multinomial logit regression models were developed to analyze injury severities for teenage and adult drivers, respectively. Elasticity analyses and transferability tests were conducted to better understand the quantitative impacts of these factors and the teenage driver injury severity model's generality. The results showed that although many of the same contributing factors were found to be significant in the both teenage and adult driver models, certain different attributes must be distinguished to specifically develop effective safety solutions for the 2 driver groups. The research findings are helpful to better understand teenage crash uniqueness and develop cost-effective solutions to reduce intersection-related teenage injury severities and facilitate driver injury mitigation research.
Brumbelow, Matthew L; Mueller, Becky C; Arbelaez, Raul A
2015-01-01
The Insurance Institute for Highway Safety (IIHS) introduced its side impact consumer information test program in 2003. Since that time, side airbags and structural improvements have been implemented across the fleet and the proportion of good ratings has increased to 93% of 2012-2014 model year vehicles. Research has shown that drivers of good-rated vehicles are 70% less likely to die in a left-side crash than drivers of poor-rated vehicles. Despite these improvements, side impact fatalities accounted for about one quarter of passenger vehicle occupant fatalities in 2012. This study is a detailed analysis of real-world cases with serious injury resulting from side crashes of vehicles with good ratings in the IIHS side impact test. NASS-CDS and Crash Injury Research and Engineering Network (CIREN) were queried for occupants of good-rated vehicles who sustained an Abbreviated Injury Scale (AIS) ≥ 3 injury in a side-impact crash. The resulting 110 cases were categorized by impact configuration and other factors that contributed to injury. Patterns of impact configuration, restraint performance, and occupant injury were identified and discussed in the context of potential upgrades to the current IIHS side impact test. Three quarters of the injured occupants were involved in near-side impacts. For these occupants, the most common factors contributing to injury were crash severities greater than the IIHS test, inadequate side-airbag performance, and lack of side-airbag coverage for the injured body region. In the cases where an airbag was present but did not prevent the injury, occupants were often exposed to loading centered farther forward on the vehicle than in the IIHS test. Around 40% of the far-side occupants were injured from contact with the struck-side interior structure, and almost all of these cases were more severe than the IIHS test. The remaining far-side occupants were mostly elderly and sustained injury from the center console, instrument panel, or seat belt. In addition, many far-side occupants were likely out of position due to events preceding the side impact and/or being unbelted. Individual changes to the IIHS side impact test have the potential to reduce the number of serious injuries in real-world crashes. These include impacting the vehicle farther forward (relevant to 28% of all cases studied), greater test severity (17%), the inclusion of far-side occupants (9%), and more restrictive injury criteria (9%). Combinations of these changes could be more effective.
Stitzel, Joel D; Weaver, Ashley A; Talton, Jennifer W; Barnard, Ryan T; Schoell, Samantha L; Doud, Andrea N; Martin, R Shayn; Meredith, J Wayne
2016-06-01
Advanced Automatic Crash Notification algorithms use vehicle telemetry measurements to predict risk of serious motor vehicle crash injury. The objective of the study was to develop an Advanced Automatic Crash Notification algorithm to reduce response time, increase triage efficiency, and improve patient outcomes by minimizing undertriage (<5%) and overtriage (<50%), as recommended by the American College of Surgeons. A list of injuries associated with a patient's need for Level I/II trauma center treatment known as the Target Injury List was determined using an approach based on 3 facets of injury: severity, time sensitivity, and predictability. Multivariable logistic regression was used to predict an occupant's risk of sustaining an injury on the Target Injury List based on crash severity and restraint factors for occupants in the National Automotive Sampling System - Crashworthiness Data System 2000-2011. The Advanced Automatic Crash Notification algorithm was optimized and evaluated to minimize triage rates, per American College of Surgeons recommendations. The following rates were achieved: <50% overtriage and <5% undertriage in side impacts and 6% to 16% undertriage in other crash modes. Nationwide implementation of our algorithm is estimated to improve triage decisions for 44% of undertriaged and 38% of overtriaged occupants. Annually, this translates to more appropriate care for >2,700 seriously injured occupants and reduces unnecessary use of trauma center resources for >162,000 minimally injured occupants. The algorithm could be incorporated into vehicles to inform emergency personnel of recommended motor vehicle crash triage decisions. Lower under- and overtriage was achieved, and nationwide implementation of the algorithm would yield improved triage decision making for an estimated 165,000 occupants annually. Copyright © 2016. Published by Elsevier Inc.
Ivarsson, Johan; Poplin, Gerald; McMurry, Tim; Crandall, Jeff; Kerrigan, Jason
2015-12-01
Planar impacts with objects and other vehicles may increase the risk and severity of injury in rollover crashes. The current study compares the frequency of injury measures (MAIS 2+, 3+, and 4+; fatal; AIS 2+ head and cervical spine; and AIS 3+ head and thorax) as well as vehicle type distribution (passenger car, SUV, van, and light truck), crash kinematics, and occupant demographics between single vehicle single event rollovers (SV Pure) and multiple event rollovers to determine which types of multiple event rollovers can be pooled with SV Pure to study rollover induced occupant injury. Four different types of multiple event rollovers were defined: single and multi-vehicle crashes for which the rollover is the most severe event (SV Prim and MV Prim) and single and multi-vehicle crashes for which the rollover is not the most severe event (SV Non-Prim and MV Non-Prim). Information from real world crashes was obtained from the National Automotive Sampling System - Crashworthiness Data System (NASS-CDS) for the period from 1995 through 2011. Belted, contained or partially ejected, adult occupants in vehicles that completed 1-16 lateral quarter turns were assigned to one of the five rollover categories. The results showed that the frequency of injury in non-primary rollovers (SV Non-Prim and MV Non-Prim) involving no more than one roof inversion is substantially greater than in SV Pure, but that this disparity diminishes for crashes involving multiple inversions. It can further be concluded that for a given number of roof inversions, the distribution of injuries and crash characteristics in SV Pure and SV Prim crashes are sufficiently similar for these categories to be considered collectively for purposes of understanding etiologies and developing strategies for prevention. Copyright © 2015 Elsevier Ltd. All rights reserved.
Potential benefits of underride guards in large truck side crashes.
Brumbelow, Matthew L
2012-01-01
To evaluate the maximum potential for side underride guards (SUGs) to reduce passenger vehicle occupant fatalities and injuries in crashes with large trucks in the United States. Examination of the Large Truck Crash Causation Study (LTCCS) identified 206 crash events involving a passenger vehicle impact with the side of a large truck. Each case was evaluated to determine whether the most severe injury sustained by a passenger vehicle occupant was a result of the impact with the side of the truck and whether an SUG could have reduced the injury severity. Data from the 2006-2008 Fatality Analysis Reporting System (FARS) and Trucks Involved in Fatal Accidents (TIFA) survey were used to compare the types of trucks involved in all fatal side impacts with passenger vehicles with the truck types in the LTCCS cases that were studied. FARS and TIFA data also were used to estimate the total annual number of passenger vehicle occupants killed in truck side impacts. In 143 of the 206 cases, the truck side impact produced the most severe injury sustained by a passenger vehicle occupant. In the other cases, no passenger vehicle occupant was injured or the most severe injury was due to an event preceding or following the truck side impact. Forty-nine of these occupants sustained injuries coded as level 3 or higher on the abbreviated injury scale (AIS) or were killed. SUGs could have reduced injury severity in 76 of the 143 cases, including 38 of the 49 cases with an AIS ≥ 3 coded injury or fatality. Semi-trailers were the most common type of impacted truck unit, both overall and when considering only cases where an SUG could have mitigated injury severity. Crashes where the front of the passenger vehicle struck the side of the semi-trailer perpendicularly or obliquely from the oncoming direction were less common overall than side-to-side and oblique/same direction crashes but more often produced an AIS ≥ 3 injury or fatality. The distribution of truck types in the LTCCS sample was similar to that in the FARS and TIFA data. Overall, around 1600 passenger vehicle occupants were killed in 2-vehicle truck side impact crashes during 2006-2008, or 22 percent of all passenger vehicle occupants who died in 2-vehicle crashes with large trucks. Structural incompatibility was a common factor in LTCCS crashes between passenger vehicles and the sides of large trucks. SUGs could have reduced injury risk in around three fourths of the crashes that produced an AIS ≥ 3 injury or fatality. Most of these crashes involved semi-trailers. However, the necessary strength and location of these SUGs present technical challenges that need to be addressed.
Comparing crash trends and severity in the northern Rocky Mountain region.
DOT National Transportation Integrated Search
2012-08-01
Safety Management Systems are federally mandated in an effort to encourage states to develop strategic programs in order to : mitigate severe crashes. In 2006, the Wyoming Department of Transportation (WYDOT) published the Wyoming Strategic Highway S...
Moradi, Ali; Soori, Hamid; Kavousi, Amir; Eshghabadi, Farshid; Jamshidi, Ensiyeh; Zeini, Salahdien
2016-01-01
Background: More than 20% of deaths from traffic crashes are related to pedestrians. This figure in Tehran, the capital of Iran, reaches to 40%. This study aimed to determine the high-risk areas and spatially analyze the traffic crashes, causing death to pedestrians in Tehran. Methods: Mapping was used to display the distribution of the crashes. Determining the distribution pattern of crashes and the hot spots/ low-risk areas were done, using Moran’s I index and Getis-Ord G, respectively. Results: A total of 198 crashes were studied; 92 of which, (46.4%) occurred in 2013 to 2014 and other 106 cases (63.6%) occurred in 2014 to 2015. The highest and the lowest frequency of crashes was related to January (26 cases) and June (10 cases), respectively. One hundred fifty- eight cases (79.8%) of crashes occurred in Tehran highways. Moran’s index showed that the studied traffic crashes had a cluster distribution (p<0.001). Getis- Ord General G index indicated that the distribution of hot and cold spots of the studied crashes was statistically significant (p<0.001). Conclusion: The majority of traffic crashes causing death to pedestrians occurred in highways located in the main entrances and exits of Tehran. Given the important role of environmental factors in the occurrence of traffic crashes related to pedestrians, identification of these factors requires more studies with casual inferences. PMID:28210615
Bahouth, George; Digges, Kennerly; Schulman, Carl
2012-01-01
This paper presents methods to estimate crash injury risk based on crash characteristics captured by some passenger vehicles equipped with Advanced Automatic Crash Notification technology. The resulting injury risk estimates could be used within an algorithm to optimize rescue care. Regression analysis was applied to the National Automotive Sampling System / Crashworthiness Data System (NASS/CDS) to determine how variations in a specific injury risk threshold would influence the accuracy of predicting crashes with serious injuries. The recommended thresholds for classifying crashes with severe injuries are 0.10 for frontal crashes and 0.05 for side crashes. The regression analysis of NASS/CDS indicates that these thresholds will provide sensitivity above 0.67 while maintaining a positive predictive value in the range of 0.20. PMID:23169132
Injury risk functions for frontal oblique collisions.
Andricevic, Nino; Junge, Mirko; Krampe, Jonas
2018-03-09
The objective of this article was the construction of injury risk functions (IRFs) for front row occupants in oblique frontal crashes and a comparison to IRF of nonoblique frontal crashes from the same data set. Crashes of modern vehicles from GIDAS (German In-Depth Accident Study) were used as the basis for the construction of a logistic injury risk model. Static deformation, measured via displaced voxels on the postcrash vehicles, was used to calculate the energy dissipated in the crash. This measure of accident severity was termed objective equivalent speed (oEES) because it does not depend on the accident reconstruction and thus eliminates reconstruction biases like impact direction and vehicle model year. Imputation from property damage cases was used to describe underrepresented low-severity crashes-a known shortcoming of GIDAS. Binary logistic regression was used to relate the stimuli (oEES) to the binary outcome variable (injured or not injured). IRFs for the oblique frontal impact and nonoblique frontal impact were computed for the Maximum Abbreviated Injury Scale (MAIS) 2+ and 3+ levels for adults (18-64 years). For a given stimulus, the probability of injury for a belted driver was higher in oblique crashes than in nonoblique frontal crashes. For the 25% injury risk at MAIS 2+ level, the corresponding stimulus for oblique crashes was 40 km/h but it was 64 km/h for nonoblique frontal crashes. The risk of obtaining MAIS 2+ injuries is significantly higher in oblique crashes than in nonoblique crashes. In the real world, most MAIS 2+ injuries occur in an oEES range from 30 to 60 km/h.
Multilevel analysis of the role of human factors in regional disparities in crash outcomes.
Adanu, Emmanuel Kofi; Smith, Randy; Powell, Lars; Jones, Steven
2017-12-01
A growing body of research has examined the disparities in road traffic safety among population groups and geographic regions. These studies reveal disparities in crash outcomes between people and regions with different socioeconomic characteristics. A critical aspect of the road traffic crash epidemic that has received limited attention is the influence of local characteristics on human elements that increase the risk of getting into a crash. This paper applies multilevel logistic regression modeling techniques to investigate the influence of driver residential factors on driver behaviors in an attempt to explain the area-based differences in the severity of road crashes across the State of Alabama. Specifically, the paper reports the effects of characteristics attributable to drivers and the geographic regions they reside on the likelihood of a crash resulting in serious injuries. Model estimation revealed that driver residence (postal code or region) accounted for about 7.3% of the variability in the probability of a driver getting into a serious injury crash, regardless of driver characteristics. The results also reveal disparities in serious injury crash rate as well as significant proportions of serious injury crashes involving no seatbelt usage, driving under influence (DUI), unemployed drivers, young drivers, distracted driving, and African American drivers among some regions. The average credit scores, average commute times, and populations of driver postal codes are shown to be significant predictors for risk of severe injury crashes. This approach to traffic crash analysis presented can serve as the foundation for evidence-based policies and also guide the implementation of targeted countermeasures. Copyright © 2017 Elsevier Ltd. All rights reserved.
An insight into the performance of road barriers - redistribution of barrier-relevant crashes.
Zou, Yaotian; Tarko, Andrew P
2016-11-01
Unlike most of traffic safety treatments that prevent crashes, road barriers reduce the severity of crash outcomes by replacing crashes with a high risk of severe injury and fatality (such as median crossover head-on collisions or collisions with high-hazard objects) with less risky events (such as collisions with barriers). This "crash conversion" is actually more complex than one-to-one replacement and it has not been studied yet. The published work estimated the reduction of selected types of crashes (typically, median crossover collisions) or the overall effect of barriers on crash severity. The objective of this study was to study the probabilities of various types of crash events possible under various road and barrier scenarios. The estimated probabilities are conditional given that at least one vehicle left the travelled way and the resulted crash had been recorded. The results are meant to deliver a useful insight onto the conversion of crashes by barriers from more to less risky to help better understand the mechanism of crash severity reduction. Such knowledge should allow engineers more accurate estimation of barriers' benefits and help researchers evaluate barriers' performance to improve the barrier's design. Seven barrier-relevant crash events possible after a vehicle departs the road could be identified based on the existing crash data and their probabilities estimated given the presence and location of three types of barriers: median concrete barriers, median and roadside W-beam steel guardrails, and high-tension median cable barriers. A multinomial logit model with variable outcomes was estimated based on 2049 barrier-relevant crashes occurred between 2003 and 2012 on 1258 unidirectional travelled ways in Indiana. The developed model allows calculating the changes in the probabilities of the barrier-relevant crash events. The results of this study indicated that road departures lead to less frequent crossings of unprotected (no barriers) medians 50-80ft. wide than for narrower medians 30-50ft wide. This benefit decreased with an increase in rollovers inside the median. Although our data indicated no median crossover events when a median barrier was present, the risk of crossovers, although low, is still present and could manifest itself if the sample were larger. The presence of barriers near a travelled way was associated with a higher risk of redirecting errant vehicles back to the roadway where they could collide with other vehicles continuing on the road. As expected, cable barriers installed on the far-side edge of a median were associated with a lower probability of being hit by errant vehicles and of redirecting vehicles into traffic than the nearside cable barriers. On the other hand, the probability of off-road non-barrier crashes was higher because vehicles penetrating the median from the unprotected side were exposed to median ditches and similar obstacles. The roadside guardrails were confirmed to reduce the percentage of hazardous off-road crashes. The results of this study facilitate a more transparent evaluation of the safety effect of road barriers. Copyright © 2016 Elsevier Ltd. All rights reserved.
Weaver, Ashley A; Gayzik, F Scott; Stitzel, Joel D
2009-01-01
Pulmonary contusion is the most common thoracic soft tissue injury encountered in motor vehicle crashes and is seen in 10-17% of all trauma admissions. This study presents a biomechanical and radiological analysis with the goal of quantifying pulmonary contusion resulting from motor vehicle crashes in order to illustrate the relationships between crash characteristics, contusion severity, and patient outcome. The 20 patients selected for this study were involved in motor vehicle crashes and subsequently enrolled in the Crash Injury and Research Engineering Network (CIREN) program at Wake Forest University Baptist Medical Center. Demographic data, sustained injuries, and crash characteristics were obtained through medical records and the CIREN database for all patients in the study. For each patient, the first chest computed tomography (CT) scan following the crash was segmented using a semi-automated approach to obtain volumes of trapped air, total lung, healthy lung, and high attenuation lung representing contused tissue. Three-dimensional models of the healthy and contused lung tissue were created for each patient. Rib fractures were present in 75% of patients and a substantial proportion of patients with pulmonary contusion injuries were involved in near side collisions. The near side door was identified as the most commonly involved component in pulmonary contusion injuries. The methodology and analysis presented in this study between crash characteristics, pulmonary contusion severity, and patient outcome are data that may contribute to future improvements in motor vehicle safety.
Haleem, Kirolos; Gan, Albert
2013-09-01
This study identifies geometric, traffic, environmental, vehicle-related, and driver-related predictors of crash injury severity on urban freeways. The study takes advantage of the mixed logit model's ability to account for unobserved effects that are difficult to quantify and may affect the model estimation, such as the driver's reaction at the time of crash. Crashes of 5 years occurring on 89 urban freeway segments throughout the state of Florida in the United States were used. Examples of severity predictors explored include traffic volume, distance of the crash to the nearest ramp, and detailed driver's age, vehicle types, and sides of impact. To show how the parameter estimates could vary, a binary logit model was compared with the mixed logit model. It was found that the at-fault driver's age, traffic volume, distance of the crash to the nearest ramp, vehicle type, side of impact, and percentage of trucks significantly influence severity on urban freeways. Additionally, young at-fault drivers were associated with a significant severity risk increase relative to other age groups. It was also observed that some variables in the binary logit model yielded illogic estimates due to ignoring the random variation of the estimation. Since the at-fault driver's age and side of impact were significant random parameters in the mixed logit model, an in-depth investigation was performed. It was noticed that back, left, and right impacts had the highest risk among middle-aged drivers, followed by young drivers, very young drivers, and finally, old and very old drivers. To reduce side impacts due to lane changing, two primary strategies can be recommended. The first strategy is to conduct campaigns to convey the hazardous effect of changing lanes at higher speeds. The second is to devise in-vehicle side crash avoidance systems to alert drivers of a potential crash risk. The study provided a promising approach to screening the predictors before fitting the mixed logit model using the random forest technique. Furthermore, potential countermeasures were proposed to reduce the severity of impacts. Copyright © 2013 National Safety Council and Elsevier Ltd. All rights reserved.
Evaluation of large truck crashes at horizontal curves on two-lane rural highways in Kansas.
DOT National Transportation Integrated Search
2012-08-01
The objective of this study was to investigate the relationship between roadway and environment-related factors and truck : crash severity at horizontal curves located on rural, two-lane state highways in Kansas. Single vehicle truck crashes and : mu...
Developing inexpensive crash countermeasures for Louisiana local roads : [technical summary].
DOT National Transportation Integrated Search
2014-03-01
Local road crash countermeasures are an important part of the overall e orts to reduce crashes and their severity in : Louisiana. The e orts to develop a local road safety program are hampered by the lack of an appropriate risk assessment : and...
DOT National Transportation Integrated Search
2016-06-01
Traditional highway safety performance metrics have been largely based on fatal crashes and more recently serious injury crashes. In the near future however, there may be less severe motor vehicle crashes due to advances in driver assistance systems,...
Doecke, Sam D; Kloeden, Craig N; Dutschke, Jeffrey K; Baldock, Matthew R J
2018-05-19
The objective of this article is to provide empirical evidence for safe speed limits that will meet the objectives of the Safe System by examining the relationship between speed limit and injury severity for different crash types, using police-reported crash data. Police-reported crashes from 2 Australian jurisdictions were used to calculate a fatal crash rate by speed limit and crash type. Example safe speed limits were defined using threshold risk levels. A positive exponential relationship between speed limit and fatality rate was found. For an example fatality rate threshold of 1 in 100 crashes it was found that safe speed limits are 40 km/h for pedestrian crashes; 50 km/h for head-on crashes; 60 km/h for hit fixed object crashes; 80 km/h for right angle, right turn, and left road/rollover crashes; and 110 km/h or more for rear-end crashes. The positive exponential relationship between speed limit and fatal crash rate is consistent with prior research into speed and crash risk. The results indicate that speed zones of 100 km/h or more only meet the objectives of the Safe System, with regard to fatal crashes, where all crash types except rear-end crashes are exceedingly rare, such as on a high standard restricted access highway with a safe roadside design.
Evolution of the crashworthiness and aggressivity of the Spanish car fleet.
Gómez Méndez, Alvaro; Aparicio Izquierdo, Francisco; Arenas Ramírez, Blanca
2010-11-01
This paper investigates the relationship between a passenger car's year of registration and its crashworthiness and aggressivity in real-world crashes. Crashworthiness is defined as the ability of a car to protect its own occupants, and has been evaluated in single and two-car crashes. Aggressivity is defined as the ability to protect users travelling in other vehicles, and has been evaluated only in two-car crashes. The dependent variable is defined as the proportion of injured drivers who are killed or seriously injured; following previous research, we refer to this magnitude as injury severity. A decrease in the injury severity of a driver is interpreted as an improvement in the crashworthiness of their car; similarly, a decrease in the injury severity of the opponent driver is regarded as an improvement in aggressivity. Data have been extracted from the Spanish Road Accident Database, which contains information on every accident registered by the police in which at least one person was injured. Two types of regression models have been used: logistic regression models in single-car crashes, and generalised estimating equations (GEE) models in two-car crashes. GEE allow to take account of the correlation between the injury severities of drivers involved in the same crash. The independent variables considered have been: year of registration of the subject car (crashworthiness component), year of registration of the opponent car (aggressivity component), and several factors related to road, driver and environment. Our models confirm that crashworthiness has largely improved in two-car crashes: when crashing into the average opponent car, drivers of cars registered before 1985 have a significantly higher probability of being killed or seriously injured than drivers of cars registered in 2000-2005 (odds ratio: 1.80; 95% confidence interval: 1.61; 2.01). In single-car crashes, the improvement in crashworthiness is very slight (odds ratio: 1.04; 95% confidence interval: 0.93; 1.16). On the other hand, we have also found a significant worsening in aggressivity in two-car crashes: the driver of the average car has a significantly lower probability of being killed or seriously injured when crashing into a car registered before 1985, than when crashing into a car registered in 2000-2005 (odds ratio: 0.52; 95% confidence interval: 0.45; 0.60). Our results are consistent with a large amount of previous research that has reported significant improvements in the protection of car occupants. They also add to some recent studies that have found a worsening in the aggressivity of modern cars. This trend may be reflecting the impact of differences in masses and travel speeds, as well as the influence of consumer choices. The precise reasons have to be investigated. Also, the causes have to be found for so large a discrepancy between crashworthiness in single and two-car crashes. 2010 Elsevier Ltd. All rights reserved.
Macroeconomic conditions and alcohol-impaired driving.
Wagenaar, A C; Streff, F M
1989-05-01
Several distinct bodies of literature indicate that economic factors influence alcohol consumption and driving behavior, including: econometric studies of effects of income and price on drinking, studies of booming and depressed communities, studies of the effects of recession on mental health and studies of the effects of the business cycle on driving patterns. The core research questions of this study were: (1) Does the state of the economy affect the rate of fatal motor vehicle crashes involving drinking drivers? and (2) Is the relationship between the state of the economy and motor vehicle fatalities mediated by effects of economic conditions on amount of alcohol consumed and amount of driving? Data were collected on multiple indicators of economic conditions, alcohol consumption, vehicle miles traveled and rates per population of fatal crashes in the United States on a monthly basis from 1976 through 1985. Nonlinear time-series modeling methods were used to estimate both direct and indirect effects and both coincident and lagged relationships. Results showed that economic conditions significantly influence fatal crash rates both directly and via changes in aggregate amount of alcohol consumed and aggregate amount of driving. However, these interrelationships at multiple lags are complex and not yet fully understood.
Chen, H Y; Ivers, R Q; Martiniuk, A L C; Boufous, S; Senserrick, T; Woodward, M; Stevenson, M; Norton, R
2010-11-01
Previous studies that found increased crash risks for young drivers of low socioeconomic status (SES) have failed to adjust for factors such as driving exposure and rural residence. This aim of this study is to examine the independent effect of SES on crash risk, adjusting for such factors, and to examine the relationship between injury severity following a crash and SES. Information on risk factors for crash collected from 20,822 newly licenced drivers aged 17-24 years in New South Wales, Australia, as part of the DRIVE Study was prospectively linked to hospitalisation data. SES was classified as high, moderate or low based on the Australia 2001 Socio-Economic Index for Areas. Poisson regression was used to model risk of crash-related hospitalisation by SES, adjusting for confounders. Two measures of injury severity--urgency of treatment and length of hospital stay--were examined by SES. Results of multivariable analysis showed that drivers from low SES areas had increased relative risk (RR 1.8, 95% CI 1.1 to 3.1) of crash-related hospitalisation compared to drivers from high SES areas. This increased risk remained when adjusting for confounders including driving exposure and rurality (RR 1.9, 95% CI 1.1 to 3.2). No significant association was found between injury severity and SES. The higher risk of crash-related hospitalisation for young drivers from low SES areas is independent of driving exposure and rural-urban differences. This finding may help improve and better target interventions for youth of low SES.
Indian reservation safety improvement program : a methodology and case study.
DOT National Transportation Integrated Search
2013-10-01
The need to reduce fatal and injury crashes on Tribal lands has been recognized for years. The U.S. has : realized a decline in fatal crashes over the past several years but fatal crashes continue to increase on : Tribal lands. Little progress has be...
Association of Michigan's older adult crashes with roadway features : final report.
DOT National Transportation Integrated Search
2017-03-31
Studies have shown that older drivers (65yrs-and-older) are prone to an increased risk of crash : involvement per vehicle mile traveled and are more likely to be severely injured or killed as a : result of a crash. The Federal Highway Administration ...
Human factors of vehicle-based lane departure warning systems : final report.
DOT National Transportation Integrated Search
2015-06-01
Run-off-road (ROR) crashes are a concern for two-lane rural and urban roadways throughout Minnesota due to the : frequency by which they contribute to fatal crashes (Minnesota Crash Facts, 2013). Mitigating the severity of the : ROR events is an on-g...
Melvin, John W; Begeman, Paul C; Faller, Ronald K; Sicking, Dean L; McClellan, Scott B; Maynard, Edwin; Donegan, Michael W; Mallott, Annette M; Gideon, Thomas W
2006-11-01
Biomechanical analysis of Indy car crashes using on-board impact recorders (Melvin et al. 1998, Melvin et al. 2001) indicates that Indy car driver protection in high-energy crashes can be achieved in frontal, side, and rear crashes with severities in the range of 100 to 135 G peak deceleration and velocity changes in the range of 50 to 70 mph. These crashes were predominantly single-car impacts with the rigid concrete walls of oval tracks. This impressive level of protection was found to be due to the unique combination of a very supportive and tight-fitting cockpit-seating package, a six-point belt restraint system, and effective head padding with an extremely strong chassis that defines the seat and cockpit of a modern Indy car. In 2000 and 2001, a series of fatal crashes in stock car racing created great concern for improving the crash protection for drivers in those racecars. Unlike the Indy car, the typical racing stock car features a more spacious driver cockpit due to its resemblance to the shape of a passenger car. The typical racing seat used in stock cars did not have the same configuration or support characteristics of the Indy car seat, and five-point belt restraints were used. The tubular steel space frame chassis of a stock car also differs from an Indy car's composite chassis structure in both form and mechanical behavior. This paper describes the application of results of the biomechanical analysis of the Indy car crash studies to the unique requirements of stock car racing driver crash protection. Sled test and full-scale crash test data using both Hybrid III frontal crash anthropomorphic test devices (ATDs) and BioSID side crash ATDs for the purpose of evaluating countermeasures involving restraint systems, seats and head/neck restraints has been instrumental in guiding these developments. In addition, the development of deformable walls for oval tracks (the SAFER Barrier) is described as an adjunct to improved occupant restraint through control of the crash forces acting on a racing car. NASCAR (National Association for Stock Car Auto Racing, Inc) implemented crash recording in stock car racing in its three national series in 2002. Data from 2925 crashes from 2002 through the 2005 season are summarized in terms of crash severity, crash direction, injury outcome, and protective system performance.
Chen, Cynthia; Lin, Haiyun; Loo, Becky P Y
2012-02-01
Pedestrians and cyclists are a vulnerable group of road users. Immigrants are disproportionally represented in pedestrian and cyclist crashes. We postulate that the mismatch in safety culture between countries of their origin and the U.S.A. contribute to their vulnerability in pedestrian and cyclist crashes. Over time, the differences may disappear and immigrants' traffic behavior gravitates toward those of native-borns. We describe this process as safety assimilation. Using the pedestrian and cyclist crash database in New York City between 2001 and 2003, we examined the effects of foreign-born population, their countries of origin, and time of entry into the USA on census tract-level pedestrian and cyclist crashes. We find that neighborhoods with a higher concentration of immigrants, especially those from Latin America, Eastern Europe, and Asia, have more crashes. Our results also exhibit a pattern of the hypothesized safety assimilation process. The study suggests a higher level of vulnerability of immigrants to pedestrian and cyclist crashes. We propose that targeted policies and programs need to be developed for immigrants of different countries of origin.
Fatal motorcycle crashes: a growing public health problem in Cambodia
Roehler, Douglas R.; Ear, Chariya; Parker, Erin M.; Sem, Panhavuth; Ballesteros, Michael F.
2015-01-01
This study examines the risk characteristics of fatal motorcycle crashes in Cambodia over a 5-year period (2007–2011). Secondary data analyses were conducted using the Cambodia Road Crash and Victim Information System, the only comprehensive and integrated road crash surveillance system in the country. Researchers from the Centers for Disease Control and Prevention and Handicap International found that (1) males are dying in motorcycle crashes roughly seven times more frequently than females; (2) motorcyclist fatalities increased by about 30% from 2007 to 2011; (3) the motorcyclist death rates per 100,000 population increased from 7.4 to 8.7 deaths from 2007 to 2011; and (4) speed-related crashes and not wearing motorcycle helmet were commonly reported for motorcyclist fatalities at approximately 50% and over 80% through the study years, respectively. Additionally, this study highlights that Cambodia has the highest motorcycle death rate in South-East Asia, far surpassing Thailand, Malaysia, and Myanmar. By recognising the patterns of fatal motorcycle crashes in Cambodia, local road-safety champions and stakeholders can design targeted interventions and preventative measures to improve road safety among motorcyclists. PMID:24499413
Preliminary analysis of the National Crash Severity Study : factors in fatal accidents
DOT National Transportation Integrated Search
1979-06-01
This study investigates the fatalities on the National Crash Severity Study (NCSS) of towaway, passenger car accidents. The analysis is in three stages. First, NCSS fatalities are compared to the fatally-injured occupants reported on the Fatal Accide...
DOT National Transportation Integrated Search
1994-11-30
A multi-year study was recently completed that examined several major highway crash types. The examined crash types included rear-end, roadway departure, backing, lane change, opposite-direction, and various intersection-related crashes, Each analysi...
DOT National Transportation Integrated Search
2016-09-01
In Virginia, sections of I-77 and I-64 in mountainous parts of the state have significant recurring fog events. These : locations have also been the sites of several chain reaction crashes involving more than 50 vehicles during fog. These crashes : w...
Coimbra, Raul; Conroy, Carol; Hoyt, David B; Pacyna, Sharon; May, MarSue; Erwin, Steve; Tominaga, Gail; Kennedy, Frank; Sise, Michael; Velky, Tom
2008-07-01
In spite of improvements in motor vehicle safety systems and crashworthiness, motor vehicle crashes remain one of the leading causes of brain injury. The purpose of this study was to determine if the damage distribution across the frontal plane affected brain injury severity of occupants in frontal impacts. Occupants in "head on" frontal impacts with a Principal Direction of Force (PDOF) equal to 11, 12, or 1o'clock who sustained serious brain injury were identified using the Crash Injury Research Engineering Network (CIREN) database. Impacts were further classified based on the damage distribution across the frontal plane as distributed, offset, and extreme offset (corner). Overall, there was no significant difference for brain injury severity (based on Glasgow Coma Scale<9, or brain injury AIS>2) comparing occupants in the different impact categories. For occupants in distributed frontal impacts, safety belt use was protective (odds ratio (OR)=0.61) and intrusion at the occupant's seat position was four times more likely to result in severe (Glasgow Coma Scale (GCS)<9) brain injury (OR=4.35). For occupants in offset frontal impacts, again safety belt use was protective against severe brain injury (OR=0.25). Possibly due to the small number of brain-injured occupants in corner impacts, safety belts did not significantly protect against increased brain injury severity during corner impacts. This study supports the importance of safety belt use to decrease brain injury severity for occupants in distributed and offset frontal crashes. It also illustrates how studying "real world" crashes may provide useful information on occupant injuries under impact circumstances not currently covered by crash testing.
Older driver crash rates in relation to type and quantity of travel.
Keall, Michael D; Frith, William J
2004-03-01
It is a well-established phenomenon that, notwithstanding their overall good crash record, older drivers have a higher than average rate of involvement in injury crashes when the rate is calculated by dividing crash numbers by distance driven. It has been hypothesised that at least some of this higher crash rate is an artefact of the different nature of driving undertaken by many older drivers. For example, driving in congested urban environments provides more opportunities for collisions than driving the same distance on a motorway. However, there have been few opportunities to investigate this theory, as relevant data are difficult to acquire. High-quality data from the New Zealand Travel Survey (1997/1998) were combined with crash data to enable a statistical model to estimate the risk of driver groups under various driving conditions characterised by the type of road used, time of day, day of week, and season of year. Despite elevated crash risks per distance driven compared with middle-aged drivers for most road types, older drivers were as safe as any other age group when driving on motorways. Accounting for the fragility of older drivers and their passengers in the risk estimates for other road types, older drivers appeared to have daytime risks comparable to 25-year-olds and night-time risks as low as any other age group. The driving patterns of older drivers (in terms of when and where they drive) were estimated to minimize their risks in comparison with the driving patterns of other age groups. These results are of interest to both policy makers and transportation planners working against the background of inevitable increases in the number of older drivers as the population ages.
Side impact crashes--factors affecting incidence and severity: review of the literature.
Chipman, Mary L
2004-03-01
Many traffic crashes are side impact collisions resulting in significant death and injury. A review was conducted of the evidence of driver, road, and vehicle characteristics affecting either the risk of occurrence or the severity of injury in such crashes for papers published from 1996 to early 2003. For drivers, evidence was found of increased crash risk or injury severity only for age and age-related medical conditions (e.g., dementia). Traffic roundabouts and other traffic control devices--stop signs, traffic lights, and so on--had mixed results; traffic controls were better than no controls, but their effectiveness varied with circumstance. Most vehicle characteristics have had little or no effect on crash occurrence. Antilock braking systems (ABS) in the striking vehicle had been anticipated to reduce the risk of crashes, but so far have demonstrated little effect. The primary emphasis in vehicle design has been on protective devices to reduce the severity of injury. Disparity in the size of the two vehicles, especially when the struck vehicle is smaller and lighter, is almost a consistent risk factor for occupant injury. The occupants of light trucks, however, when struck by passengers cars on the opposite side, were at higher risk of injury. Wearing seat belts had a consistently protective effect; airbags did not, but there were few studies, and no field studies, of lateral airbags found. Of all the characteristics examined, vehicle design, including occupant restraints, is the most easily modified in the short term, although road design, traffic control, and the monitoring of older drivers may also prove effective in reducing side impact crashes in the longer term.
Risk factors affecting injury severity determined by the MAIS score.
Ferreira, Sara; Amorim, Marco; Couto, Antonio
2017-07-04
Traffic crashes result in a loss of life but also impact the quality of life and productivity of crash survivors. Given the importance of traffic crash outcomes, the issue has received attention from researchers and practitioners as well as government institutions, such as the European Commission (EC). Thus, to obtain detailed information on the injury type and severity of crash victims, hospital data have been proposed for use alongside police crash records. A new injury severity classification based on hospital data, called the maximum abbreviated injury scale (MAIS), was developed and recently adopted by the EC. This study provides an in-depth analysis of the factors that affect injury severity as classified by the MAIS score. In this study, the MAIS score was derived from the International Classification of Diseases. The European Union adopted an MAIS score equal to or greater than 3 as the definition for a serious traffic crash injury. Gains are expected from using both police and hospital data because the injury severities of the victims are detailed by medical staff and the characteristics of the crash and the site of its occurrence are also provided. The data were obtained by linking police and hospital data sets from the Porto metropolitan area of Portugal over a 6-year period (2006-2011). A mixed logit model was used to understand the factors that contribute to the injury severity of traffic victims and to explore the impact of these factors on injury severity. A random parameter approach offers methodological flexibility to capture individual-specific heterogeneity. Additionally, to understand the importance of using a reliable injury severity scale, we compared MAIS with length of hospital stay (LHS), a classification used by several countries, including Portugal, to officially report injury severity. To do so, the same statistical technique was applied using the same variables to analyze their impact on the injury severity classified according to LHS. This study showed the impact of variables, such as the presence of blood alcohol, the use of protection devices, the type of crash, and the site characteristics, on the injury severity classified according to the MAIS score. Additionally, the sex and age of the victims were analyzed as risk factors, showing that elderly and male road users are highly associated with MAIS 3+ injuries. The comparison between the marginal effects of the variables estimated by the MAIS and LHS models showed significant differences. In addition to the differences in the magnitude of impact of each variable, we found that the impact of the road environment variable was dependent on the injury severity classification. The differences in the effects of risk factors between the classifications highlight the importance of using a reliable classification of injury severity. Additionally, the relationship between LHS and MAIS levels is quite different among countries, supporting the previous conclusion that bias is expected in the assessment of risk factors if an injury severity classification other than MAIS is used.
Ecological Associations of Alcohol Outlets with Underage and Young Adult Injuries
Gruenewald, Paul J.; Freisthler, Bridget; Remer, Lillian; LaScala, Elizabeth A.; Treno, Andrew J.; Ponicki, William R.
2010-01-01
Objective This paper argues that associations between rates of three specific problems related to alcohol (i.e., accidents, traffic crashes, and assaults) should be differentially related to densities of off-premise outlets among underage youth and young adults based upon age related-patterns of alcohol outlet use. Methods Zip code-level population models assessed local and distal effects of alcohol outlets upon rates of hospital discharges for these outcomes. Results Densities of off-premise alcohol outlets were significantly related to injuries from accidents, assaults, and traffic crashes for both underage youth and young adults. Densities of bars were associated with more assaults and densities of restaurants were associated with more traffic crash injuries for young adults. Conclusions The distribution of alcohol-related injuries relative to alcohol outlets reflect patterns of alcohol outlet use. PMID:20028361
Dong, Chunjiao; Xie, Kun; Zeng, Jin; Li, Xia
2018-04-01
Highway safety laws aim to influence driver behaviors so as to reduce the frequency and severity of crashes, and their outcomes. For one specific highway safety law, it would have different effects on the crashes across severities. Understanding such effects can help policy makers upgrade current laws and hence improve traffic safety. To investigate the effects of highway safety laws on crashes across severities, multivariate models are needed to account for the interdependency issues in crash counts across severities. Based on the characteristics of the dependent variables, multivariate dynamic Tobit (MVDT) models are proposed to analyze crash counts that are aggregated at the state level. Lagged observed dependent variables are incorporated into the MVDT models to account for potential temporal correlation issues in crash data. The state highway safety law related factors are used as the explanatory variables and socio-demographic and traffic factors are used as the control variables. Three models, a MVDT model with lagged observed dependent variables, a MVDT model with unobserved random variables, and a multivariate static Tobit (MVST) model are developed and compared. The results show that among the investigated models, the MVDT models with lagged observed dependent variables have the best goodness-of-fit. The findings indicate that, compared to the MVST, the MVDT models have better explanatory power and prediction accuracy. The MVDT model with lagged observed variables can better handle the stochasticity and dependency in the temporal evolution of the crash counts and the estimated values from the model are closer to the observed values. The results show that more lives could be saved if law enforcement agencies can make a sustained effort to educate the public about the importance of motorcyclists wearing helmets. Motor vehicle crash-related deaths, injuries, and property damages could be reduced if states enact laws for stricter text messaging rules, higher speeding fines, older licensing age, and stronger graduated licensing provisions. Injury and PDO crashes would be significantly reduced with stricter laws prohibiting the use of hand-held communication devices and higher fines for drunk driving. Copyright © 2018 Elsevier Ltd. All rights reserved.
Fink, Joshua; Kwigizile, Valerian; Oh, Jun-Seok
2016-06-01
Despite seeing widespread usage worldwide, adaptive traffic control systems have experienced relatively little use in the United States. Of the systems used, the Sydney Coordinated Adaptive Traffic System (SCATS) is the most popular in America. Safety benefits of these systems are not as well understood nor as commonly documented. This study investigates the safety benefits of adaptive traffic control systems by using the large SCATS-based system in Oakland County, MI known as FAST-TRAC. This study uses data from FAST-TRAC-controlled intersections in Oakland County and compares a wide variety of geometric, traffic, and crash characteristics to similar intersections in metropolitan areas elsewhere in Michigan. Data from 498 signalized intersections are used to conduct a cross-sectional analysis. Negative binomial models are used to estimate models for three dependent crash variables. Multinomial logit models are used to estimate an injury severity model. A variable tracking the presence of FAST-TRAC controllers at intersections is used in all models to determine if a SCATS-based system has an impact on crash occurrences or crash severity. Estimates show that the presence of SCATS-based controllers at intersections is likely to reduce angle crashes by up to 19.3%. Severity results show a statistically significant increase in non-serious injuries, but not a significant reduction in incapacitating injuries or fatal accidents. Copyright © 2016 Elsevier Ltd and National Safety Council. All rights reserved.
The effect of crash experience on changes in risk taking among urban and rural young people.
Lin, Mau-Roung; Huang, Wenzheng; Hwang, Hei-Fen; Wu, Hong-Dar Isaac; Yen, Lee-Lan
2004-03-01
A 20-month prospective study was conducted to investigate the effect of motorcycle crash experience on changes in risk taking among 2514 urban and 2304 rural students in Taiwan. Risk taking was assessed using a 14-item self-administered questionnaire at the beginning and end of the study. A risk-taking score for each student at the initial and the last follow-up assessments was generated from adding up points across all 14 items. For exposure variables, the study documented past motorcycle crash history at the initial assessment and collected detailed information about any motorcycle crash involvement that occurred during the study period. A general linear mixed model was applied to assess the effects of prior and recent crash involvements on the path of risk-taking behavior. The results show that at the initial assessment, students with crash experience had higher risk-taking levels than those without crash experience. However, crash experience, irregardless of whether it was measured in terms of crash history prior to the study, crash frequency, time elapsed since the last crash, or crash severity, did not significantly change the risk-taking path among students, even though its effect differed between urban and rural areas.
The influence of daily sleep patterns of commercial truck drivers on driving performance.
Chen, Guang Xiang; Fang, Youjia; Guo, Feng; Hanowski, Richard J
2016-06-01
Fatigued and drowsy driving has been found to be a major cause of truck crashes. Lack of sleep is the number one cause of fatigue and drowsiness. However, there are limited data on the sleep patterns (sleep duration, sleep percentage in the duration of non-work period, and the time when sleep occurred) of truck drivers in non-work periods and the impact on driving performance. This paper examined sleep patterns of 96 commercial truck drivers during non-work periods and evaluated the influence these sleep patterns had on truck driving performance. Data were from the Naturalistic Truck Driving Study. Each driver participated in the study for approximately four weeks. A shift was defined as a non-work period followed by a work period. A total of 1397 shifts were identified. Four distinct sleep patterns were identified based on sleep duration, sleep start/end point in a non-work period, and the percentage of sleep with reference to the duration of non-work period. Driving performance was measured by safety-critical events, which included crashes, near-crashes, crash-relevant conflicts, and unintentional lane deviations. Negative binomial regression was used to evaluate the association between the sleep patterns and driving performance, adjusted for driver demographic information. The results showed that the sleep pattern with the highest safety-critical event rate was associated with shorter sleep, sleep in the early stage of a non-work period, and less sleep between 1 a.m. and 5 a.m. This study also found that male drivers, with fewer years of commercial vehicle driving experience and higher body mass index, were associated with deteriorated driving performance and increased driving risk. The results of this study could inform hours-of-service policy-making and benefit safety management in the trucking industry. Published by Elsevier Ltd.
Nirula, R; Pintar, F A
2008-01-01
Thoracic trauma secondary to motor vehicle crashes (MVC) continues to be a major cause of morbidity and mortality. Specific vehicle features may increase the risk of severe thoracic injury when striking the occupant. We sought to determine which vehicle contact points were associated with an increased risk of severe thoracic injury in MVC to focus subsequent design modifications necessary to reduce thoracic injury. The National Automotive Sampling System (NASS) databases from 1993 to 2001 and the Crash Injury Research and Engineering Network (CIREN) databases from 1996 to 2004 were analyzed separately using univariate and multivariate logistic regression stratified by restraint use and crash direction. The risk of driver thoracic injury, defined as an abbreviated injury scale (AIS) of score > or =3, was determined as it related to specific points of contact between the vehicle and the driver. The incidence of severe chest injury in NASS and CIREN were 5.5% and 33%, respectively. The steering wheel, door panel, armrest, and seat were identified as contact points associated with an increased risk of severe chest injury. The door panel and arm rest were consistently a frequent cause of severe injury in both the NASS and CIREN data. Several vehicle contact points, including the steering wheel, door panel, armrest and seat are associated with an increased risk of severe thoracic injury when striking the occupant. These elements need to be further investigated to determine which characteristics need to be manipulated in order to reduce thoracic trauma during a crash.
Laureshyn, Aliaksei; De Ceunynck, Tim; Karlsson, Christoffer; Svensson, Åse; Daniels, Stijn
2017-01-01
Most existing traffic conflict indicators do not sufficiently take into account the severity of the injuries resulting from a collision had it occurred. Thus far, most of the indicators that have been developed express the severity of a traffic encounter as their proximity to a collision in terms of time or space. This paper presents the theoretical framework and the first implementation of Extended Delta-V as a measure of traffic conflict severity in site-based observations. It is derived from the concept of Delta-V as it is applied in crash reconstructions, which refers to the change of velocity experienced by a road user during a crash. The concept of Delta-V is recognised as an important predictor of crash outcome severity. The paper explains how the measure is operationalised within the context of traffic conflict observations. The Extended Delta-V traffic conflict measure integrates the proximity to a crash as well as the outcome severity in the event a crash would have taken place, which are both important dimensions in defining the severity of a traffic event. The results from a case study are presented in which a number of traffic conflict indicators are calculated for interactions between left turning vehicles and vehicles driving straight through a signalised intersection. The results suggest that the Extended Delta-V indicator seems to perform well at selecting the most severe traffic events. The paper discusses how the indicator overcomes a number of limitations of traditional measures of conflict severity. While this is a promising first step towards operationalising an improved measure of traffic conflict severity, additional research is needed to further develop and validate the indicator. Copyright © 2016 The Author(s). Published by Elsevier Ltd.. All rights reserved.
DOT National Transportation Integrated Search
2000-01-01
Although considerable progress has been made over the past several years in making highway travel safer, the frequency and severity of speed-related crashes on the nation's highways continue to be of concern. Understanding the factors associated with...
Ogunmuyiwa, Stella Aimiede; Gbolahan, Olalere Omoyosola; Ayantunde, Abiodun Abraham; Odewabi, Adenike Abidemi
2015-01-01
Trauma remains a leading cause of maxillofacial injury globally. Changing etiological factors and patterns of maxillofacial injury continue to be reported and are largely modulated by socio-geographic and environmental factors. It is important to have an in-depth understanding of the pattern and etiology in a particular region before effective preventive measures can be developed. The aim was to evaluate the patterns, etiological factors, and management of maxillofacial injuries in Ogun state, Nigeria. A prospective descriptive cohort study of all consecutive patients that presented with maxillofacial injuries at our center between January and December 2013. Information about demographic data, types of maxillofacial and associated injury, etiology of injury, treatment received and complications were collected and analyzed. Seventy patients presented with maxillofacial injury during the study period with a male to female ratio of 4:1. The age range was 9 months to 60 years with a mean of 30.11 ± standard deviation 14.97 years. Majority of the facial fractures were due to motorcycle related crashes. There were 57.1% mandibular fractures and 55.7% middle third fractures. Closed reduction with maxillo-mandibular fixation was the major method of treatment of facial fractures. Postoperative complications were observed in 11.4% of patients. Road traffic crashes (RTCs) remain the leading etiological factor of maxillofacial injuries in our center. Enforcement of stricter traffic regulations and possibly replacement of motorcycles with tricycles for commercial transportation may help to reduce the incidence of RTCs.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhan, Xianyuan; Aziz, H. M. Abdul; Ukkusuri, Satish V.
Our study investigates the Multivariate Poisson-lognormal (MVPLN) model that jointly models crash frequency and severity accounting for correlations. The ordinary univariate count models analyze crashes of different severity level separately ignoring the correlations among severity levels. The MVPLN model is capable to incorporate the general correlation structure and takes account of the over dispersion in the data that leads to a superior data fitting. But, the traditional estimation approach for MVPLN model is computationally expensive, which often limits the use of MVPLN model in practice. In this work, a parallel sampling scheme is introduced to improve the original Markov Chainmore » Monte Carlo (MCMC) estimation approach of the MVPLN model, which significantly reduces the model estimation time. Two MVPLN models are developed using the pedestrian vehicle crash data collected in New York City from 2002 to 2006, and the highway-injury data from Washington State (5-year data from 1990 to 1994) The Deviance Information Criteria (DIC) is used to evaluate the model fitting. The estimation results show that the MVPLN models provide a superior fit over univariate Poisson-lognormal (PLN), univariate Poisson, and Negative Binomial models. Moreover, the correlations among the latent effects of different severity levels are found significant in both datasets that justifies the importance of jointly modeling crash frequency and severity accounting for correlations.« less
Zhan, Xianyuan; Aziz, H. M. Abdul; Ukkusuri, Satish V.
2015-11-19
Our study investigates the Multivariate Poisson-lognormal (MVPLN) model that jointly models crash frequency and severity accounting for correlations. The ordinary univariate count models analyze crashes of different severity level separately ignoring the correlations among severity levels. The MVPLN model is capable to incorporate the general correlation structure and takes account of the over dispersion in the data that leads to a superior data fitting. But, the traditional estimation approach for MVPLN model is computationally expensive, which often limits the use of MVPLN model in practice. In this work, a parallel sampling scheme is introduced to improve the original Markov Chainmore » Monte Carlo (MCMC) estimation approach of the MVPLN model, which significantly reduces the model estimation time. Two MVPLN models are developed using the pedestrian vehicle crash data collected in New York City from 2002 to 2006, and the highway-injury data from Washington State (5-year data from 1990 to 1994) The Deviance Information Criteria (DIC) is used to evaluate the model fitting. The estimation results show that the MVPLN models provide a superior fit over univariate Poisson-lognormal (PLN), univariate Poisson, and Negative Binomial models. Moreover, the correlations among the latent effects of different severity levels are found significant in both datasets that justifies the importance of jointly modeling crash frequency and severity accounting for correlations.« less
Comprehensive target populations for current active safety systems using national crash databases.
Kusano, Kristofer D; Gabler, Hampton C
2014-01-01
The objective of active safety systems is to prevent or mitigate collisions. A critical component in the design of active safety systems is the identification of the target population for a proposed system. The target population for an active safety system is that set of crashes that a proposed system could prevent or mitigate. Target crashes have scenarios in which the sensors and algorithms would likely activate. For example, the rear-end crash scenario, where the front of one vehicle contacts another vehicle traveling in the same direction and in the same lane as the striking vehicle, is one scenario for which forward collision warning (FCW) would be most effective in mitigating or preventing. This article presents a novel set of precrash scenarios based on coded variables from NHTSA's nationally representative crash databases in the United States. Using 4 databases (National Automotive Sampling System-General Estimates System [NASS-GES], NASS Crashworthiness Data System [NASS-CDS], Fatality Analysis Reporting System [FARS], and National Motor Vehicle Crash Causation Survey [NMVCCS]) the scenarios developed in this study can be used to quantify the number of police-reported crashes, seriously injured occupants, and fatalities that are applicable to proposed active safety systems. In this article, we use the precrash scenarios to identify the target populations for FCW, pedestrian crash avoidance systems (PCAS), lane departure warning (LDW), and vehicle-to-vehicle (V2V) or vehicle-to-infrastructure (V2I) systems. Crash scenarios were derived using precrash variables (critical event, accident type, precrash movement) present in all 4 data sources. This study found that these active safety systems could potentially mitigate approximately 1 in 5 of all severity and serious injury crashes in the United States and 26 percent of fatal crashes. Annually, this corresponds to 1.2 million all severity, 14,353 serious injury (MAIS 3+), and 7412 fatal crashes. In addition, we provide the source code for the crash scenarios as an appendix (see online supplement) to this article so that researchers can use the crash scenarios in future research.
Filtness, A J; Armstrong, K A; Watson, A; Smith, S S
2017-02-01
Sleep-related (SR) crashes are an endemic problem the world over. However, police officers report difficulties in identifying sleepiness as a crash contributing factor. One approach to improving the sensitivity of SR crash identification is by applying a proxy definition post hoc to crash reports. To identify the prominent characteristics of SR crashes and highlight the influence of proxy definitions, ten years of Queensland (Australia) police reports of crashes occurring in ≥100km/h speed zones were analysed. In Queensland, two approaches are routinely taken to identifying SR crashes. First, attending police officers identify crash causal factors; one possible option is 'fatigue/fell asleep'. Second, a proxy definition is applied to all crash reports. Those meeting the definition are considered SR and added to the police-reported SR crashes. Of the 65,204 vehicle operators involved in crashes 3449 were police-reported as SR. Analyses of these data found that male drivers aged 16-24 years within the first two years of unsupervised driving were most likely to have a SR crash. Collision with a stationary object was more likely in SR than in not-SR crashes. Using the proxy definition 9739 (14.9%) crashes were classified as SR. Using the proxy definition removes the findings that SR crashes are more likely to involve males and be of high severity. Additionally, proxy defined SR crashes are no less likely at intersections than not-SR crashes. When interpreting crash data it is important to understand the implications of SR identification because strategies aimed at reducing the road toll are informed by such data. Without the correct interpretation, funding could be misdirected. Improving sleepiness identification should be a priority in terms of both improvement to police and proxy reporting. Copyright © 2015 Elsevier Ltd. All rights reserved.
Savino, Giovanni; Rizzi, Matteo; Brown, Julie; Piantini, Simone; Meredith, Lauren; Albanese, Bianca; Pierini, Marco; Fitzharris, Michael
2014-01-01
In 2006, Motorcycle Autonomous Emergency Braking (MAEB) was developed by a European Consortium (Powered Two Wheeler Integrated Safety, PISa) as a crash severity countermeasure for riders. This system can detect an obstacle through sensors in the front of the motorcycle and brakes automatically to achieve a 0.3 g deceleration if the collision is inevitable and the rider does not react. However, if the rider does brake, full braking force is applied automatically. Previous research into the potential benefits of MAEB has shown encouraging results. However, this was based on MAEB triggering algorithms designed for motorcycle crashes involving impacts with fixed objects and rear-end crashes. To estimate the full potential benefit of MAEB, there is a need to understand the full spectrum of motorcycle crashes and further develop triggering algorithms that apply to a wider spectrum of crash scenarios. In-depth crash data from 3 different countries were used: 80 hospital admittance cases collected during 2012-2013 within a 3-h driving range of Sydney, Australia, 40 crashes with Injury Severity Score (ISS)>15 collected in the metropolitan area of Florence, Italy, during 2009-2012, and 92 fatal crashes that occurred in Sweden during 2008-2009. In the first step, the potential applicability of MAEB among the crashes was assessed using a decision tree method. To achieve this, a new triggering algorithm for MAEB was developed to address crossing scenarios as well as crashes involving stationary objects. In the second step, the potential benefit of MAEB across the applicable crashes was examined by using numerical computer simulations. Each crash was reconstructed twice-once with and once without MAEB deployed. The principal finding is that using the new triggering algorithm, MAEB is seen to apply to a broad range of multivehicle motorcycle crashes. Crash mitigation was achieved through reductions in impact speed of up to approximately 10 percent, depending on the crash scenario and the initial vehicle pre-impact speeds. This research is the first attempt to evaluate MAEB with simulations on a broad range of crash scenarios using in-depth data. The results give further insights into the feasibility of MAEB in different speed ranges. It is clear then that MAEB is a promising technology that warrants further attention by researchers, manufacturers, and regulators.
Pai, Chih-Wei; Saleh, Wafaa
2007-03-01
The fact that motorcycle users tend to be more vulnerable to injuries than those using other motorized vehicles may act synergistically with the complexity of conflicting movements between vehicles and motorcycles to increase injury severity in a junction-type accident. A junction-type collision tends to be more severe than a non-junction case due to the fact that some of the injurious crashes such as angle-collision commonly occur. Existing studies have applied several statistical modeling techniques to examine influential factors on the occurrences of different crashes among motorized vehicles but surprisingly very little has empirically explored whether a particular crash type, resulting from a junction-type accident, is more injurious to motorcyclists. This article attempts to investigate whether a particular collision is more deadly to motorcyclists conditioned on crash occurrence at T-junctions in the U.K., while controlling for environment, vehicle, and demographic factors. The statistical modeling technique employed is the ordered probit models using the data extracted from the STATS19 accident injury database (1999-2004). The modeling found determinants of injury severity among motorcyclists at T-junctions in the U.K. For example, an approach-turn/head-on collision is much more injurious to motorcyclists; and, those riding in early morning (i.e., 0000-0659) are more likely to be severely injured. This study offers a guideline for future research, as well as insight into potential prevention strategies that might help moderate motorcyclist injuries.
Injury severity data for front and second row passengers in frontal crashes.
Atkinson, Theresa; Leszek Gawarecki; Tavakoli, Massoud
2016-06-01
The data contained here were obtained from the National Highway Transportation Safety Administration׳s National Automotive Sampling System - Crashworthiness Data System (NASS-CDS) for the years 2008-2014. This publically available data set monitors motor vehicle crashes in the United States, using a stratified random sample frame, resulting in information on approximately 5000 crashes each year that can be utilized to create national estimates for crashes. The NASS-CDS data sets document vehicle, crash, and occupant factors. These data can be utilized to examine public health, law enforcement, roadway planning, and vehicle design issues. The data provided in this brief are a subset of crash events and occupants. The crashes provided are exclusively frontal crashes. Within these crashes, only restrained occupants who were seated in the right front seat position or the second row outboard seat positions were included. The front row and second row data sets were utilized to construct occupant pairs crashes where both a right front seat occupant and a second row occupant were available. Both unpaired and paired data sets are provided in this brief.
Injury severity data for front and second row passengers in frontal crashes
Atkinson, Theresa; Leszek Gawarecki; Tavakoli, Massoud
2016-01-01
The data contained here were obtained from the National Highway Transportation Safety Administration׳s National Automotive Sampling System – Crashworthiness Data System (NASS-CDS) for the years 2008–2014. This publically available data set monitors motor vehicle crashes in the United States, using a stratified random sample frame, resulting in information on approximately 5000 crashes each year that can be utilized to create national estimates for crashes. The NASS-CDS data sets document vehicle, crash, and occupant factors. These data can be utilized to examine public health, law enforcement, roadway planning, and vehicle design issues. The data provided in this brief are a subset of crash events and occupants. The crashes provided are exclusively frontal crashes. Within these crashes, only restrained occupants who were seated in the right front seat position or the second row outboard seat positions were included. The front row and second row data sets were utilized to construct occupant pairs crashes where both a right front seat occupant and a second row occupant were available. Both unpaired and paired data sets are provided in this brief. PMID:27077084
Evaluation of a policy to reduce youth tractor crashes on public roads.
Marlenga, B; Doty, B C; Berg, R L; Linneman, J G
2006-02-01
Evaluate the effectiveness of a United States state law, Wisconsin Act 455, in reducing highway tractor crashes involving youth operators. Policy outcome evaluation involving review of a retrospective case series. Youth highway tractor crashes from Wisconsin for the years 1994-2003 that resulted in a fatality, injury, and/or property damage. One hundred and forty six tractor crash cases involving operators younger than 16 years. Describe and model the tractor crash patterns before and after enactment of the law, and examine the relation between the contributing circumstances identified in the crash reports and the content covered in the mandated tractor certification course. There was neither a significant change in the number of youth tractor crashes after the law was passed, nor any reduction in the proportion of crashes where the youth operator was designated at fault. The tractor certification course did not cover the major factors contributing to youth tractor crashes on public roads. No significant effect of the law was detected and crash rates at the end of the study period were similar to those before Wisconsin Act 455. The authors'findings should not be construed to suggest that public policy, in general, is an ineffective strategy for the prevention of pediatric agricultural injuries. Negotiating a balance in public policy debates will be a challenge, but it is clear that future policy initiatives need to identify and implement the right policy for the right problem.
DOT National Transportation Integrated Search
2017-06-01
The effect of low visibility on both crash occurrence and severity is a major concern in the traffic safety field. It is known that crashes tend to be more severe in low visibility conditions than under normal clear conditions. Thus, there is a drast...
DOT National Transportation Integrated Search
2009-04-28
This report presents the analysis conducted to identify the factors that contribute to severe and fatal crash occurrence on multilane corridors. The authors preliminary investigation using simultaneous ordered probit model provided enough evidence...
Liu, Shu-Yuan; Perez, Miguel A; Lau, Nathan
2018-04-01
This study investigated the association between driving safety and seven sleep disorders amongst 3541 participants of the Second Strategic Highway Research Program (SHRP 2) naturalistic driving study. SHRP 2 collected naturalistic driving data from participants between 16 and 98 years old by instrumenting participants' vehicles. The analyses used logistic regression to determine the likelihood of crash or near-crash involvement, Poisson log-linear regression to assess crash or near-crash rate, and ordinal logistic regression to assess driver maneuver appropriateness and crash or near-crash severity. These analyses did not account for any medical treatments for the sleep disorders. Females with restless legs syndrome/Willis-Ekbom disease (RLS/WED), drivers with insomnia or narcolepsy, are associated with significantly higher risk of crash or near-crash. Drivers with shift work sleep disorder (SWSD) are associated with significantly increased crash or near-crash rate. Females with RLS/WED or sleep apnea and drivers with SWSD are associated with less safe driver maneuver and drivers with periodic limb movement disorder are associated with more severe events. The four analyses provide no evidence of safety decrements associated with migraine. This study is the first examination on the association between seven sleep disorders and different measures of driving risk using large-scale naturalistic driving study data. The results corroborate much of the existing simulator and epidemiological research related to sleep-disorder patients and their driving safety, but add ecological validity to those findings. These results contribute to the empirical basis for medical professionals, policy makers, and employers in making decisions to aid individuals with sleep disorders in balancing safety and personal mobility.
A comparison of KABCO and AIS injury severity metrics using CODES linked data.
Burch, Cynthia; Cook, Lawrence; Dischinger, Patricia
2014-01-01
The research objective is to compare the consistency of distributions between crash assigned (KABCO) and hospital assigned (Abbreviated Injury Scale, AIS) injury severity scoring systems for 2 states. The hypothesis is that AIS scores will be more consistent between the 2 studied states (Maryland and Utah) than KABCO. The analysis involved Crash Outcome Data Evaluation System (CODES) data from 2 states, Maryland and Utah, for years 2006-2008. Crash report and hospital inpatient data were linked probabilistically and International Classification of Diseases (CMS 2013) codes from hospital records were translated into AIS codes. KABCO scores from police crash reports were compared to those AIS scores within and between the 2 study states. Maryland appears to have the more severe crash report KABCO scoring for injured crash participants, with close to 50 percent of all injured persons being coded as a level B or worse, and Utah observes approximately 40 percent in this group. When analyzing AIS scores, some fluctuation was seen within states over time, but the distribution of MAIS is much more comparable between states. Maryland had approximately 85 percent of hospitalized injured cases coded as MAIS = 1 or minor. In Utah this percentage was close to 80 percent for all 3 years. This is quite different from the KABCO distributions, where Maryland had a smaller percentage of cases in the lowest injury severity category as compared to Utah. This analysis examines the distribution of 2 injury severity metrics different in both design and collection and found that both classifications are consistent within each state from 2006 to 2008. However, the distribution of both KABCO and Maximum Abbreviated Injury Scale (MAIS) varies between the states. MAIS was found to be more consistent between states than KABCO.
Weiler, G; Risse, M
1989-01-01
On February 8th 1988, a two-motor passenger aircraft of Metroliner type with 21 people on board entered a front of heavy weather at an altitude of 900 m and crashed after being struck by lightning which led to complete breakdown of the electrical systems on board. The site of the crash was in the marshy Ruhr meadows. The formation of the terrain enabled a subdivision into plan squares for rescue. The identification of the 21 bodies was carried out in the Essen Institute of Forensic Medicine in collaboration with the identification commission of the Federal Criminal Investigation Office. The experience and recommendations for future (possibly larger-scale) disasters derived from this are described. Furthermore, the accident pattern in the casualties typical for this air crash is discussed.
Under-reporting of road traffic crash data in Ghana.
Salifu, Mohammed; Ackaah, Williams
2012-01-01
Having reliable estimates of the shortfalls in road traffic crash data is an important prerequisite for setting more realistic targets for crash/casualty reduction programmes and for a better appreciation of the socio-economic significance of road traffic crashes. This study was carried out to establish realistic estimates of the overall shortfall (under-reporting) in the official crash statistics in Ghana over an eight-year period (1997-2004). Surveys were conducted at hospitals and among drivers to generate relevant alternative data which were then matched against records in police crash data files and the official database. Overall shortfalls came from two sources, namely, 'non-reporting' and 'under-recording'. The results show that the level of non-reporting varied significantly with the severity of the crash from about 57% for property damage crashes through 8% for serious injury crashes to 0% for fatal crashes. Crashes involving cyclists and motorcyclists were also substantially non-reported. Under-recording on the other hand declined significantly over the period from an average of 37% in 1997-1998 to 27% in 2003-2004. Thus, the official statistics of road traffic crashes in Ghana are subject to significant shortfalls that need to be accounted for. Correction factors have therefore been suggested for adjusting the official data.
Pedestrian Injury Patterns According to Car and Casualty Characteristics in France
Martin, Jean-Louis; Lardy, Audrey; Laumon, Bernard
2011-01-01
This paper describes the injury patterns of pedestrians involved in collisions with cars, compares them with other road casualties and estimates the possible effect of car front profile on injury location. Injury patterns were identified using the Rhône Road Trauma Registry which covers all the casualties resulting from crashes in the Rhône Département (1.6 million inhabitants) who seek medical care in health facilities. Fatality rates were estimated from national police reports for the same years (1996–2007), and the two data sources were linked to obtain information on the front profile of the striking car. As with all groups of road users, most of the pedestrians involved in car crashes were young. However elderly people were overrepresented when the size of the exposed population was taken into account. The most frequently injured body regions were the lower extremities (50% of victims), the head/face/neck (38%) and the upper extremities (27%). Pelvic injuries were much more common for women. The most severe injuries (AIS4+) were mostly to the head and thorax, for all groups of road users. However, pedestrians sustained twice as many head injuries as thoracic injuries. When the front profiles were grouped together according to the most common car types in Europe, the risk of being killed was higher for MPVs. More specifically, the risk of sustaining an AIS2+ thoracic injury was higher in a collision with an MPV. Our study confirms that it is quite justified for the tests based on European Enhanced Vehicle-Safety Committee guidelines to be focused on the head and the lower extremities. However, no test procedure exists for thoracic injuries, which is the body region with the second highest number of severe or fatal injuries. PMID:22105391
Patterns of injury seen in road crash victims in a South African trauma centre.
Parkinson, Fran; Kent, S; Aldous, C; Oosthuizen, G; Clarke, D L
2013-10-22
Road traffic crashes (RTCs) account for a significant burden of disease in South Africa. This prospective study reviews basic demographic and outcome data of patients who sustained an RTC-related injury and analyses the common patterns of injury associated with specific mechanisms of injury. We reviewed all patients seen at a single regional hospital (Edendale Hospital, Pietermaritzburg, KwaZulu-Natal) with injuries sustained in RTCs over a 10-week period. State mortuary data were gathered on all RTC-related fatalities over the same period. Three hundred and five patients were seen at the hospital over the 10-week period. The average transfer time to hospital was 9.2 hours (range 1 - 17 hours) One hundred patients were admitted and the rest were discharged home from the emergency department. Of the admitted cohort, 59 were motor vehicle occupants (MVC group) and 41 were pedestrians (PVC group). PVC patients commonly had lower limb, head, radio-ulnar and clavicular injuries, while MVC patients commonly had neck and intra-abdominal injuries. Thirty-seven patients had multiple injuries. The in-hospital mortality rate was 5.6%, but the overall mortality rate was 10.0%, as 15 patients died at the scene. Patterns of injury differ according to the mechanism of injury. Pedestrians impact against various parts of the vehicle and the ground and so sustain injuries to their arms and legs. Occupants of vehicles impact against the dashboard and steering wheel and are more likely to sustain torso injuries. The low number of severe injuries and multiple injuries and the relatively low inpatient mortality rate are a consequence of the triage effect of long delays in transfer. More severely injured patients are more likely to die at the scene.
Urie, Yohan; Velaga, Nagendra R; Maji, Avijit
2016-10-02
Road crashes are considered as the eighth leading causes of death. There is a wide disparity in crash severity and law enforcement efficiency among low-, medium-, and high-income countries. It would be helpful to review the crash severity trends in these countries, identify the vulnerable road users, and understand the law enforcement effectiveness in devising efficient road safety improvement strategies. The crash severity, fatality rate among various age groups, and law enforcement strategies of 10 countries representing low-income (i.e., India and Morocco), medium-income (i.e. Argentina, South Korea, and Greece), and high-income (i.e., Australia, Canada, France, the UK, and the United States) are studied and compared for a period of 5 years (i.e., 2008 to 2012). The critical parameters affecting road safety are identified and correlated with education, culture, and basic compliance with traffic safety laws. In the process, possible road safety improvement strategies are identified for low-income countries. The number of registered vehicles shows an increasing trend for low-income countries as do the crash rate and crash severity. Compliance related to seat belt and helmet laws is high in high-income countries. In addition, recent seat belt- and helmet-related safety programs in middle-income countries helped to curb fatalities. Noncompliance with safety laws in low-income countries is attributed to education, culture, and inefficient law enforcement. Efficient law enforcement and effective safety education taking into account cultural diversity are the key aspects to reduce traffic-related injuries and fatalities in low-income countries like India.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wenzel, Tom
2012-08-01
NHTSA recently completed a logistic regression analysis (Kahane 2012) updating its 2003 and 2010 studies of the relationship between vehicle mass and US fatality risk per vehicle mile traveled (VMT). The new study updates the previous analyses in several ways: updated FARS data for 2002 to 2008 involving MY00 to MY07 vehicles are used; induced exposure data from police reported crashes in several additional states are added; a new vehicle category for car-based crossover utility vehicles (CUVs) and minivans is created; crashes with other light-duty vehicles are divided into two groups based on the crash partner vehicle’s weight, and amore » category for all other fatal crashes is added; and new control variables for new safety technologies and designs, such as electronic stability controls (ESC), side airbags, and methods to meet voluntary agreement to improve light truck compatibility with cars, are included.« less
Factors that influence chest injuries in rollovers.
Digges, Kennerly; Eigen, Ana; Tahan, Fadi; Grzebieta, Raphael
2014-01-01
The design of countermeasures to reduce serious chest injuries for belted occupants involved in rollover crashes requires an understanding of the cause of these injuries and of the test conditions to assure the effectiveness of the countermeasures. This study defines rollover environments and occupant-to-vehicle interactions that cause chest injuries for belted drivers. The NASS-CDS was examined to determine the frequency and crash severity for belted drivers with serious (Abbreviated Injury Scale [AIS] 3+) chest injuries in rollovers. Case studies of NASS crashes with serious chest injuries sustained by belted front occupants were undertaken and damage patterns were determined. Vehicle rollover tests with dummies were examined to determine occupant motion in crashes with damage similar to that observed in the NASS cases. Computer simulations were performed to further explore factors that could contribute to chest injury. Finite element model (FEM) vehicle models with both the FEM Hybrid III dummy and THUMS human model were used in the simulations. Simulation of rollovers with 6 quarter-turns or less indicated that increases in the vehicle pitch, either positive or negative, increased the severity of dummy chest loadings. This finding was consistent with vehicle damage observations from NASS cases. For the far-side occupant, the maximum chest loadings were caused by belt and side interactions during the third quarter-turn and by the center console loading during the fourth quarter-turn. The results showed that the THUMS dummy produced more realistic kinematics and improved insights into skeletal and chest organ loadings compared to the Hybrid III dummy. These results suggest that a dynamic rollover test to encourage chest injury reduction countermeasures should induce a roll of at least 4 quarter-turns and should also include initial vehicle pitch and/or yaw so that the vehicle's axis of rotation is not aligned with its inertial roll axis during the initial stage of the rollover.
Determinants of pedestrian and bicyclist crash severity by party at fault in San Francisco, CA.
Salon, Deborah; McIntyre, Andrew
2018-01-01
Pedestrian and bicyclist safety is of growing concern, especially given the increasing numbers of urban residents choosing to walk and bike. Sharing the roads with automobiles, these road users are particularly vulnerable. An intuitive conceptual model is proposed of the determinants of injury severity in crashes between vehicles and nonmotorized road users. Using 10 years of crash data from San Francisco, CA, we estimate logistic regression models to illuminate key determinants of crash severity for both pedestrian and bicyclist collisions. The analyses are separated by party at fault to test the novel hypothesis that environmental factors affecting driver speed and reaction time may be especially important when the driver is not at fault. Pedestrian results are broadly consistent with prior research, and offer considerable support for this hypothesis. The strongest predictors of injury severity include pedestrian advanced age, driver sobriety, vehicle type, and a set of variables that help determine driver speed and reaction time. Bicyclist results were weaker overall, and the distinction by party at fault was less important. Copyright © 2017 Elsevier Ltd. All rights reserved.
Data-driven train set crash dynamics simulation
NASA Astrophysics Data System (ADS)
Tang, Zhao; Zhu, Yunrui; Nie, Yinyu; Guo, Shihui; Liu, Fengjia; Chang, Jian; Zhang, Jianjun
2017-02-01
Traditional finite element (FE) methods are arguably expensive in computation/simulation of the train crash. High computational cost limits their direct applications in investigating dynamic behaviours of an entire train set for crashworthiness design and structural optimisation. On the contrary, multi-body modelling is widely used because of its low computational cost with the trade-off in accuracy. In this study, a data-driven train crash modelling method is proposed to improve the performance of a multi-body dynamics simulation of train set crash without increasing the computational burden. This is achieved by the parallel random forest algorithm, which is a machine learning approach that extracts useful patterns of force-displacement curves and predicts a force-displacement relation in a given collision condition from a collection of offline FE simulation data on various collision conditions, namely different crash velocities in our analysis. Using the FE simulation results as a benchmark, we compared our method with traditional multi-body modelling methods and the result shows that our data-driven method improves the accuracy over traditional multi-body models in train crash simulation and runs at the same level of efficiency.
Antona-Makoshi, Jacobo; Mikami, Koji; Lindkvist, Mats; Davidsson, Johan; Schick, Sylvia
2018-08-01
This study estimated the frequency and risk of Moderate-to-Maximal traumatic brain injuries sustained by occupants in motor vehicle crashes in the US. National Automotive Sampling System - Crashworthiness Data System crashes that occurred in years 2001-2015 with light vehicles produced 2001 or later were incorporated in the study. Crash type, crash severity, car model year, belt usage and occupant age and sex were controlled for in the analysis. The results showed that Moderate concussions account for 79% of all MAIS brain 2+ injuries. Belted occupants were at lower risks than unbelted occupants for most brain injury categories, including concussions. After controlling for the effects of age and crash severity, belted female occupants involved in frontal crashes were estimated to be 1.5 times more likely to sustain a concussion than male occupants in similar conditions. Belted elderly occupants were found to be at 10.5 and 8 times higher risks for sub-dural haemorrhages than non-elderly belted occupants in frontal and side crashes, respectively. Adopted occupant protection strategies appear to be insufficient to achieve significant decreases in risk of both life-threatening brain injuries and concussions for all car occupants. Further effort to develop occupant and injury specific strategies for the prevention of brain injuries are needed. This study suggests that these strategies may consider prioritization of life-threatening brain vasculature injuries, particularly in elderly occupants, and concussion injuries, particularly in female occupants. Copyright © 2018 Elsevier Ltd. All rights reserved.
Zhang, Meng; Khattak, Asad J; Liu, Jun; Clarke, David
2018-08-01
Rail-trespassing crashes that involve various levels of injuries to pedestrians are under-researched. Rail trespassing could occur at crossings where pedestrians are present at the wrong time and at non-crossings where pedestrians are not legally allowed to be present. This paper presents a comparative study examining rail-trespassing crashes in two contexts: highway-rail grade crossings vs. non-crossings. How pre-crash trespassing behaviors and other factors (e.g., crash time, locations, and socio-demographics) differ between grade crossings and non-crossings are explored. The analysis relies on a ten-year (2006-2015) database of rail-pedestrian trespassing crash records extracted from a Federal Railroad Administration safety database. Of these 7157 rail-pedestrian trespassing crashes, 6236 (87%) occurred at non-crossings, while 921 (13%) occurred at grade crossings. About 60% of the crashes were fatal at both crossings and non-crossings. The most prevalent pre-crash trespassing behavior is running or walking, 63% at grade crossings and 44% at non-crossings. Lying or sleeping account for 29% of non-crossing crashes, whereas they are 3.6% at grade crossings. A unique aspect of the study is that a diverse set of variables based on geographic variations across counties along with crash or injury data are modeled. Considering the data structure and heterogeneity that may exist due to unobserved factors, the multilevel mixed-effect ordered logistic regressions models are estimated. The results show that the correlates of injury severity differ across highway-rail grade crossings and non-crossings. For example, lying or sleeping on or near tracks contributed to higher chances of fatal injury in both contexts, however, they were relatively more injurious at grade crossings. The analytical results can provide guidance on railway safety improvement plans. Copyright © 2018. Published by Elsevier Ltd.
Washington, Simon; Haque, Md Mazharul; Oh, Jutaek; Lee, Dongmin
2014-05-01
Hot spot identification (HSID) aims to identify potential sites-roadway segments, intersections, crosswalks, interchanges, ramps, etc.-with disproportionately high crash risk relative to similar sites. An inefficient HSID methodology might result in either identifying a safe site as high risk (false positive) or a high risk site as safe (false negative), and consequently lead to the misuse the available public funds, to poor investment decisions, and to inefficient risk management practice. Current HSID methods suffer from issues like underreporting of minor injury and property damage only (PDO) crashes, challenges of accounting for crash severity into the methodology, and selection of a proper safety performance function to model crash data that is often heavily skewed by a preponderance of zeros. Addressing these challenges, this paper proposes a combination of a PDO equivalency calculation and quantile regression technique to identify hot spots in a transportation network. In particular, issues related to underreporting and crash severity are tackled by incorporating equivalent PDO crashes, whilst the concerns related to the non-count nature of equivalent PDO crashes and the skewness of crash data are addressed by the non-parametric quantile regression technique. The proposed method identifies covariate effects on various quantiles of a population, rather than the population mean like most methods in practice, which more closely corresponds with how black spots are identified in practice. The proposed methodology is illustrated using rural road segment data from Korea and compared against the traditional EB method with negative binomial regression. Application of a quantile regression model on equivalent PDO crashes enables identification of a set of high-risk sites that reflect the true safety costs to the society, simultaneously reduces the influence of under-reported PDO and minor injury crashes, and overcomes the limitation of traditional NB model in dealing with preponderance of zeros problem or right skewed dataset. Copyright © 2014 Elsevier Ltd. All rights reserved.
Dimitriou, Loukas; Stylianou, Katerina; Abdel-Aty, Mohamed A
2018-03-01
Rear-end crashes are one of the most frequently occurring crash types, especially in urban networks. An understanding of the contributing factors and their significant association with rear-end crashes is of practical importance and will help in the development of effective countermeasures. The objective of this study is to assess rear-end crash potential at a microscopic level in an urban environment, by investigating vehicle-by-vehicle interactions. To do so, several traffic parameters at the individual vehicle level have been taken into consideration, for capturing car-following characteristics and vehicle interactions, and to investigate their effect on potential rear-end crashes. In this study rear-end crash potential was estimated based on stopping distance between two consecutive vehicles, and four rear-end crash potential cases were developed. The results indicated that 66.4% of the observations were estimated as rear-end crash potentials. It was also shown that rear-end crash potential was presented when traffic flow and speed standard deviation were higher. Also, locational characteristics such as lane of travel and location in the network were found to affect drivers' car following decisions and additionally, it was shown that speeds were lower and headways higher when Heavy Goods Vehicles lead. Finally, a model-based behavioral analysis based on Multinomial Logit regression was conducted to systematically identify the statistically significant variables in explaining rear-end risk potential. The modeling results highlighted the significance of the explanatory variables associated with rear-end crash potential, however it was shown that their effect varied among different model configurations. The outcome of the results can be of significant value for several purposes, such as real-time monitoring of risk potential, allocating enforcement units in urban networks and designing targeted proactive safety policies. Copyright © 2018 Elsevier Ltd. All rights reserved.
Crash avoidance potential of four large truck technologies.
Jermakian, Jessica S
2012-11-01
The objective of this paper was to estimate the maximum potential large truck crash reductions in the United States associated with each of four crash avoidance technologies: side view assist, forward collision warning/mitigation, lane departure warning/prevention, and vehicle stability control. Estimates accounted for limitations of current systems. Crash records were extracted from the 2004-08 files of the National Automotive Sampling System General Estimates System (NASS GES) and the Fatality Analysis Reporting System (FARS). Crash descriptors such as location of damage on the vehicle, road characteristics, time of day, and precrash maneuvers were reviewed to determine whether the information or action provided by each technology potentially could have prevented the crash. Of the four technologies, side view assist had the greatest potential for preventing large truck crashes of any severity; the technology is potentially applicable to 39,000 crashes in the United States each year, including 2000 serious and moderate injury crashes and 79 fatal crashes. Vehicle stability control is another promising technology, with the potential to prevent or mitigate up to 31,000 crashes per year including more serious crashes--up to 7000 moderate-to-serious injury crashes and 439 fatal crashes per year. Vehicle stability control could prevent or mitigate up to 20 and 11 percent of moderate-to-serious injury and fatal large truck crashes, respectively. Forward collision warning has the potential to prevent as many as 31,000 crashes per year, including 3000 serious and moderate injury crashes and 115 fatal crashes. Finally, 10,000 large truck crashes annually were relevant to lane departure warning/prevention systems. Of these, 1000 involved serious and moderate injuries and 247 involved fatal injuries. There is great potential effectiveness for truck-based crash avoidance systems. However, it is yet to be determined how drivers will interact with the systems. Actual effectiveness of crash avoidance systems will not be known until sufficient real-world experience has been gained. Copyright © 2012 Elsevier Ltd. All rights reserved.
Osman, Mohamed; Mishra, Sabyasachee; Paleti, Rajesh
2018-05-18
This study analyzes the injury severity of commercially-licensed drivers involved in single-vehicle crashes. Considering the discrete ordinal nature of injury severity data, the ordered response modeling framework was adopted. The moderating effect of driver's age on all other factors was examined by segmenting the parameters by driver's age group. Additional effects of the different drivers' age groups are taken into consideration through interaction terms. Unobserved heterogeneity of the different covariates was investigated using the Mixed Generalized Ordered Response Probit (MGORP) model. The empirical analysis was conducted using four years of the Highway Safety Information System (HSIS) data that included 6247 commercially-licensed drivers involved in single-vehicle crashes in the state of Minnesota. The MGORP model elasticity effects indicate that key factors that increase the likelihood of severe crashes for commercially-licensed drivers across all age groups include: lack of seatbelt usage, collision with a fixed object, speeding, vehicle age of 11 years or more, wind, night time, weekday, and female drivers. Also, the effects of several covariates were found to vary across different age groups. Copyright © 2018 Elsevier Ltd. All rights reserved.
DOT National Transportation Integrated Search
1999-09-01
A deterministic algorithm was developed which allowed data from Department of Transportation motor vehicle crash records, state mortality registry records, and hospital admission and emergency department records to be linked for analysis of the types...
Sunnevång, Cecilia; Rosén, Erik; Boström, Ola; Lechelt, Ulf
2010-01-01
Side airbags reduce the risk of fatal injury by approximately 30%. Due to limited real-life data the risk reducing effect for serious injury has not yet been established. Since side airbags are mainly designed and validated for crash severities used in available test procedures little is known regarding the protective effect when severity increases. The objective of this study was to understand for which crash severities AIS3+ thorax occupant protection in car-to-car nearside collisions need to and can be improved. The aim was fulfilled by means of real life data, for older cars without side airbag, and a series of car-to-car tests performed with the WorldSID 50%-ile in modern and older cars at different impact speeds. The real life data showed that the risk of AIS3+ injury was highest for the thorax followed by the pelvis and head. For both non-senior and senior occupants, most thorax injuries were sustained at lateral delta-v from 20 km/h to 40 km/h. In this severity range, senior occupants were found to have approximately four times higher risk of thoracic injury than non-senior occupants. The crash tests at lateral impact speed 55 km/h (delta-v 32 km/h) confirmed the improved performance at severities represented in current legal and rating tests. The structural integrity of the modern car impacted at 70 km/h showed a potential for improved side impact protection by interior countermeasures. PMID:21050600
Sunnevång, Cecilia; Rosén, Erik; Boström, Ola; Lechelt, Ulf
2010-01-01
Side airbags reduce the risk of fatal injury by approximately 30%. Due to limited real-life data the risk reducing effect for serious injury has not yet been established. Since side airbags are mainly designed and validated for crash severities used in available test procedures little is known regarding the protective effect when severity increases.The objective of this study was to understand for which crash severities AIS3+ thorax occupant protection in car-to-car nearside collisions need to and can be improved. The aim was fulfilled by means of real life data, for older cars without side airbag, and a series of car-to-car tests performed with the WorldSID 50%-ile in modern and older cars at different impact speeds.The real life data showed that the risk of AIS3+ injury was highest for the thorax followed by the pelvis and head. For both non-senior and senior occupants, most thorax injuries were sustained at lateral delta-v from 20 km/h to 40 km/h. In this severity range, senior occupants were found to have approximately four times higher risk of thoracic injury than non-senior occupants. The crash tests at lateral impact speed 55 km/h (delta-v 32 km/h) confirmed the improved performance at severities represented in current legal and rating tests. The structural integrity of the modern car impacted at 70 km/h showed a potential for improved side impact protection by interior countermeasures.
Costs of Alcohol-Involved Crashes, United States, 2010
Zaloshnja, Eduard; Miller, Ted R.; Blincoe, Lawrence J.
2013-01-01
This paper estimates total and unit costs of alcohol-involved crashes in the U.S. in 2010. With methods from earlier studies, we estimated costs per crash survivor by MAIS, body part, and fracture/dislocation involvement. We multiplied them times 2010 crash incidence estimates from NHTSA data sets, with adjustments for underreporting of crashes and their alcohol involvement. The unit costs are lifetime costs discounted at 3%. To develop medical costs, we combined 2008 Health Care Utilization Program national data for hospitalizations and ED visits of crash survivors with prior estimates of post-discharge costs. Productivity losses drew on Current Population Survey and American Time Use Survey data. Quality of life losses came from a 2011 AAAM paper and property damage from insurance data. We built a hybrid incidence file comprised of 2008–2010 and 1984–86 NHTSA crash surveillance data, weighted with 2010 General Estimates System weights. Fatality data came from the 2010 FARS. An estimated 12% of 2010 crashes but only 0.9% of miles driven were alcohol-involved (BAC > .05). Alcohol-involved crashes cost an estimated $125 billion. That is 22.5% of the societal cost of all crashes. Alcohol-attributable crashes accounted for an estimated 22.5% of US auto liability insurance payments. Alcohol-involved crashes cost $0.86 per drink. Above the US BAC limit of .08, crash costs were $8.37 per mile driven; 1 in 788 trips resulted in a crash and 1 in 1,016 trips in an arrest. Unit costs for crash survivors by severity are higher for impaired driving than for other crashes. That suggests national aggregate impaired driving cost estimates in other countries are substantial underestimates if they are based on all-crash unit costs. PMID:24406941
Honeybul, Stephen; Ho, Kwok M
2016-09-01
Predicting long-term neurological outcomes after severe traumatic brain (TBI) is important, but which prognostic model in the context of decompressive craniectomy has the best performance remains uncertain. This prospective observational cohort study included all patients who had severe TBI requiring decompressive craniectomy between 2004 and 2014, in the two neurosurgical centres in Perth, Western Australia. Severe disability, vegetative state, or death were defined as unfavourable neurological outcomes. Area under the receiver-operating-characteristic curve (AUROC) and slope and intercept of the calibration curve were used to assess discrimination and calibration of the CRASH (Corticosteroid-Randomisation-After-Significant-Head injury) and IMPACT (International-Mission-For-Prognosis-And-Clinical-Trial) models, respectively. Of the 319 patients included in the study, 119 (37%) had unfavourable neurological outcomes at 18-month after decompressive craniectomy for severe TBI. Both CRASH (AUROC 0.86, 95% confidence interval 0.81-0.90) and IMPACT full-model (AUROC 0.85, 95% CI 0.80-0.89) were similar in discriminating between favourable and unfavourable neurological outcome at 18-month after surgery (p=0.690 for the difference in AUROC derived from the two models). Although both models tended to over-predict the risks of long-term unfavourable outcome, the IMPACT model had a slightly better calibration than the CRASH model (intercept of the calibration curve=-4.1 vs. -5.7, and log likelihoods -159 vs. -360, respectively), especially when the predicted risks of unfavourable outcome were <80%. Both CRASH and IMPACT prognostic models were good in discriminating between favourable and unfavourable long-term neurological outcome for patients with severe TBI requiring decompressive craniectomy, but the calibration of the IMPACT full-model was better than the CRASH model. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.
Vachal, Kimberly; Tumuhairwe, Esther K; Berwick, Mark
2009-04-01
The North Dakota Legislature recently passed a law exempting the state's agricultural truck fleet from a federal safety program requirement for rear-guard equipment on large trucks. This equipment has been shown to reduce crash severity when a passenger vehicle collides with the rear of the truck. This study uses truck fleet, truck crash, and injury severity data to estimate the public safety benefit derived from passenger-vehicle underride protection during rear-end crashes involving large agricultural trucks in North Dakota. A benefit-cost analysis of crash injury avoidance is developed based on the frequency and severity of rear-end truck collisions in North Dakota between 2001 and 2007. The injury avoidance benefits and commercial vehicle safety grant benefits are estimated to be $11.4 to $20.2 million during the seven-year depreciable truck life. The public safety benefits for rear-impact guards are higher than the estimated lifetime cost for the equipment and maintenance of $8.1 million.
Lee, Jaeyoung; Yasmin, Shamsunnahar; Eluru, Naveen; Abdel-Aty, Mohamed; Cai, Qing
2018-02-01
In traffic safety literature, crash frequency variables are analyzed using univariate count models or multivariate count models. In this study, we propose an alternative approach to modeling multiple crash frequency dependent variables. Instead of modeling the frequency of crashes we propose to analyze the proportion of crashes by vehicle type. A flexible mixed multinomial logit fractional split model is employed for analyzing the proportions of crashes by vehicle type at the macro-level. In this model, the proportion allocated to an alternative is probabilistically determined based on the alternative propensity as well as the propensity of all other alternatives. Thus, exogenous variables directly affect all alternatives. The approach is well suited to accommodate for large number of alternatives without a sizable increase in computational burden. The model was estimated using crash data at Traffic Analysis Zone (TAZ) level from Florida. The modeling results clearly illustrate the applicability of the proposed framework for crash proportion analysis. Further, the Excess Predicted Proportion (EPP)-a screening performance measure analogous to Highway Safety Manual (HSM), Excess Predicted Average Crash Frequency is proposed for hot zone identification. Using EPP, a statewide screening exercise by the various vehicle types considered in our analysis was undertaken. The screening results revealed that the spatial pattern of hot zones is substantially different across the various vehicle types considered. Copyright © 2017 Elsevier Ltd. All rights reserved.
Doohan, Isabelle; Björnstig, Ulf; Östlund, Ulrika; Saveman, Britt-Inger
2017-04-01
The aim of this study was to explore physical and mental consequences and injury mechanisms among bus crash survivors to identify aspects that influence recovery. The study participants were the total population of survivors (N=56) from a bus crash in Sweden. The study had a mixed-methods design that provided quantitative and qualitative data on injuries, mental well-being, and experiences. Results from descriptive statistics and qualitative thematic analysis were interpreted and integrated in a mixed-methods analysis. Among the survivors, 11 passengers (20%) sustained moderate to severe injuries, and the remaining 45 (80%) had minor or no physical injuries. Two-thirds of the survivors screened for posttraumatic stress disorder (PTSD) risk were assessed, during the period of one to three months after the bus crash, as not being at-risk, and the remaining one-third were at-risk. The thematic analysis resulted in themes covering the consequences and varying aspects that affected the survivors' recoveries. The integrated findings are in the form of four "core cases" of survivors who represent a combination of characteristics: injury severity, mental well-being, social context, and other aspects hindering and facilitating recovery. Core case Avery represents a survivor who had minor or no injuries and who demonstrated a successful mental recovery. Core case Blair represents a survivor with moderate to severe injuries who experienced a successful mental recovery. Core case Casey represents a survivor who sustained minor injuries or no injuries in the crash but who was at-risk of developing PTSD. Core case Daryl represents a survivor who was at-risk of developing PTSD and who also sustained moderate to severe injuries in the crash. The present study provides a multi-faceted understanding of mass-casualty incident (MCI) survivors (ie, having minor injuries does not always correspond to minimal risk for PTSD and moderate to severe injuries do not always correspond to increased risk for PTSD). Injury mitigation measures (eg, safer roadside material and anti-lacerative windows) would reduce the consequences of bus crashes. A well-educated rescue team and a compassionate and competent social environment will facilitate recovery. Doohan I , Björnstig U , Östlund U , Saveman BI . Exploring injury panorama, consequences, and recovery among bus crash survivors: a mixed-methods research study. Prehosp Disaster Med. 2017;32(2):165-174.
Crash avoidance potential of four passenger vehicle technologies.
Jermakian, Jessica S
2011-05-01
The objective was to update estimates of maximum potential crash reductions in the United States associated with each of four crash avoidance technologies: side view assist, forward collision warning/mitigation, lane departure warning/prevention, and adaptive headlights. Compared with previous estimates (Farmer, 2008), estimates in this study attempted to account for known limitations of current systems. Crash records were extracted from the 2004-08 files of the National Automotive Sampling System General Estimates System (NASS GES) and the Fatality Analysis Reporting System (FARS). Crash descriptors such as vehicle damage location, road characteristics, time of day, and precrash maneuvers were reviewed to determine whether the information or action provided by each technology potentially could have prevented or mitigated the crash. Of the four crash avoidance technologies, forward collision warning/mitigation had the greatest potential for preventing crashes of any severity; the technology is potentially applicable to 1.2 million crashes in the United States each year, including 66,000 serious and moderate injury crashes and 879 fatal crashes. Lane departure warning/prevention systems appeared relevant to 179,000 crashes per year. Side view assist and adaptive headlights could prevent 395,000 and 142,000 crashes per year, respectively. Lane departure warning/prevention was relevant to the most fatal crashes, up to 7500 fatal crashes per year. A combination of all four current technologies potentially could prevent or mitigate (without double counting) up to 1,866,000 crashes each year, including 149,000 serious and moderate injury crashes and 10,238 fatal crashes. If forward collision warning were extended to detect objects, pedestrians, and bicyclists, it would be relevant to an additional 3868 unique fatal crashes. There is great potential effectiveness for vehicle-based crash avoidance systems. However, it is yet to be determined how drivers will interact with the systems. The actual effectiveness of these systems will not be known until sufficient real-world experience has been gained. Copyright © 2010 Elsevier Ltd. All rights reserved.
Habibovic, Azra; Tivesten, Emma; Uchida, Nobuyuki; Bärgman, Jonas; Ljung Aust, Mikael
2013-01-01
To develop relevant road safety countermeasures, it is necessary to first obtain an in-depth understanding of how and why safety-critical situations such as incidents, near-crashes, and crashes occur. Video-recordings from naturalistic driving studies provide detailed information on events and circumstances prior to such situations that is difficult to obtain from traditional crash investigations, at least when it comes to the observable driver behavior. This study analyzed causation in 90 video-recordings of car-to-pedestrian incidents captured by onboard cameras in a naturalistic driving study in Japan. The Driving Reliability and Error Analysis Method (DREAM) was modified and used to identify contributing factors and causation patterns in these incidents. Two main causation patterns were found. In intersections, drivers failed to recognize the presence of the conflict pedestrian due to visual obstructions and/or because their attention was allocated towards something other than the conflict pedestrian. In incidents away from intersections, this pattern reoccurred along with another pattern showing that pedestrians often behaved in unexpected ways. These patterns indicate that an interactive advanced driver assistance system (ADAS) able to redirect the driver's attention could have averted many of the intersection incidents, while autonomous systems may be needed away from intersections. Cooperative ADAS may be needed to address issues raised by visual obstructions. Copyright © 2012 Elsevier Ltd. All rights reserved.
Built environment effects on cyclist injury severity in automobile-involved bicycle crashes.
Chen, Peng; Shen, Qing
2016-01-01
This analysis uses a generalized ordered logit model and a generalized additive model to estimate the effects of built environment factors on cyclist injury severity in automobile-involved bicycle crashes, as well as to accommodate possible spatial dependence among crash locations. The sample is drawn from the Seattle Department of Transportation bicycle collision profiles. This study classifies the cyclist injury types as property damage only, possible injury, evident injury, and severe injury or fatality. Our modeling outcomes show that: (1) injury severity is negatively associated with employment density; (2) severe injury or fatality is negatively associated with land use mixture; (3) lower likelihood of injuries is observed for bicyclists wearing reflective clothing; (4) improving street lighting can decrease the likelihood of cyclist injuries; (5) posted speed limit is positively associated with the probability of evident injury and severe injury or fatality; (6) older cyclists appear to be more vulnerable to severe injury or fatality; and (7) cyclists are more likely to be severely injured when large vehicles are involved in crashes. One implication drawn from this study is that cities should increase land use mixture and development density, optimally lower posted speed limits on streets with both bikes and motor vehicles, and improve street lighting to promote bicycle safety. In addition, cyclists should be encouraged to wear reflective clothing. Copyright © 2015 Elsevier Ltd. All rights reserved.
Clothing-related motorcycle injuries in Pakistan: findings from a surveillance study.
Khan, Uzma R; Bhatti, Junaid A; Shamim, M Shahzad; Zia, Nukhba; Razzak, Junaid A; Jooma, Rashid
2015-01-01
This study aims to assess the burden and patterns of clothing-related motorcycle injuries in Karachi, Pakistan. Data were extracted from an ongoing traffic injury surveillance system. In three years (2007-2009), out of 99155 road traffic injury cases there were 986 (0.9%) cases of clothing-related motorcycle injuries. Most cases were females (73.9%) and pillion riders (80.6%). The crashes involving clothing-related injuries were mostly single vehicle (98.5%), and largely resulted in injuries to the external body (60.3%), limbs (51.0%), head (41.5%) and face (35.9%). One-third of injuries were either moderate (26.7%) or severe (10.2%) while 10 (1.01%) deaths were reported. Female gender (11.4%), age ≥ 45 years (19.4%), pillion riding (11.3%) and crashes occurring at intersections (12.3%) were more likely to result in moderate or severe injury as compared to other users (P < 0.001). Injuries due to entanglement of loose fitting clothing in motorcycles are not uncommon in Karachi. Awareness campaigns for prevention of such injuries may involve promotion of appropriate dressing for motorcycle riding including close wrapping of clothes and encouraging installations of covers on the rear wheels and drive chains.
Aviation Careers Series: Airport Careers
DOT National Transportation Integrated Search
1996-01-29
Intelligent Transportation Systems (ITS) offer tools to address transportation safety on several fronts, including improving control of the vehicle, mitigating circumstances that contribute to crashes, and responding more quickly to crashes that do o...
All-terrain vehicles (ATVs) on the road: a serious traffic safety and public health concern.
Denning, Gerene; Jennissen, Charles; Harland, Karisa; Ellis, David; Buresh, Christopher
2013-01-01
On-road all-terrain vehicle (ATV) crashes are frequent occurrences that disproportionately impact rural communities. These crashes occur despite most states having laws restricting on-road ATV use. A number of overall risk factors for ATV-related injuries have been identified (e.g., lack of helmet, carrying passengers). However, few studies have determined the relative contribution of these and other factors to on-road crashes and injuries. The objective of our study was to determine whether there were differences between on- and off-road ATV crashes in their demographics and/or mechanisms and outcomes of injuries. Data were derived from our statewide ATV injury surveillance database (2002-2009). Crash location and crash and injury mechanisms were coded using a modification of the Department of Transportation (DOT) coding system. Descriptive analyses and statistical comparisons (chi-square test) of variables were performed. Multivariate logistic regression analysis was used to determine relative risk. 976 records were included in the final analysis, with 38 percent of the injured individuals from on-road crashes. Demographics were similar for crashes at each location, with approximately 80 percent males, 30 percent under the age of 16, and 15 percent passengers. However, females and youths under 16 were over 4 times more likely to be passengers (P ≤ 0.0001), regardless of crash location. Compared to those off-road, on-road crash victims were approximately 10 times more likely to be involved in a vehicle-vehicle collision (P < 0.001), 3 times more likely to have a severe brain injury (P < 0.001), and twice as likely to have suffered major trauma (P < 0.001). Adult operators in on-road crashes were also twice as likely to test positive for alcohol as those off-road (P < 0.05). Helmet use significantly reduced the odds of sustaining a brain injury and on-road victims were only half as likely to be helmeted (P < 0.01). More than 1 in 3 on-road crashes involved a collision with another vehicle, suggesting that ATVs on the road represent a potential traffic safety concern. Of note, helmets were associated with reduced risk for the number and severity of brain injuries, providing further support for the importance of helmet use. Finally, even controlling for helmet use, on-road crash victims suffered more major trauma and severe brain injuries than those off-road. Overall, our data reinforce the importance of laws restricting ATV road use and the need for effective enforcement, as well as the need to increase user education about ATV road-use laws and the dangers of riding on the roads.
Brubacher, Jeffrey R.; Chan, Herbert; Erdelyi, Shannon; Schuurman, Nadine; Amram, Ofer
2016-01-01
Background British Columbia, Canada is a geographically large jurisdiction with varied environmental and socio-cultural contexts. This cross-sectional study examined variation in motor vehicle crash rates across 100 police patrols to investigate the association of crashes with key explanatory factors. Methods Eleven crash outcomes (total crashes, injury crashes, fatal crashes, speed related fatal crashes, total fatalities, single-vehicle night-time crashes, rear-end collisions, and collisions involving heavy vehicles, pedestrians, cyclists, or motorcyclists) were identified from police collision reports and insurance claims and mapped to police patrols. Six potential explanatory factors (intensity of traffic law enforcement, speed limits, climate, remoteness, socio-economic factors, and alcohol consumption) were also mapped to police patrols. We then studied the association between crashes and explanatory factors using negative binomial models with crash count per patrol as the response variable and explanatory factors as covariates. Results Between 2003 and 2012 there were 1,434,239 insurance claim collisions, 386,326 police reported crashes, and 3,404 fatal crashes. Across police patrols, there was marked variation in per capita crash rate and in potential explanatory factors. Several factors were associated with crash rates. Percent roads with speed limits ≤ 60 km/hr was positively associated with total crashes, injury crashes, rear end collisions, and collisions involving pedestrians, cyclists, and heavy vehicles; and negatively associated with single vehicle night-time crashes, fatal crashes, fatal speeding crashes, and total fatalities. Higher winter temperature was associated with lower rates of overall collisions, single vehicle night-time collisions, collisions involving heavy vehicles, and total fatalities. Lower socio-economic status was associated with higher rates of injury collisions, pedestrian collisions, fatal speeding collisions, and fatal collisions. Regions with dedicated traffic officers had fewer fatal crashes and fewer fatal speed related crashes but more rear end crashes and more crashes involving cyclists or pedestrians. The number of traffic citations per 1000 drivers was positively associated with total crashes, fatal crashes, total fatalities, fatal speeding crashes, injury crashes, single vehicle night-time crashes, and heavy vehicle crashes. Possible explanations for these associations are discussed. Conclusions There is wide variation in per capita rates of motor vehicle crashes across BC police patrols. Some variation is explained by factors such as climate, road type, remoteness, socioeconomic variables, and enforcement intensity. The ability of explanatory factors to predict crash rates would be improved if considered with local traffic volume by all travel modes. PMID:27099930
Kusano, Kristofer D; Gabler, Hampton C
2010-01-01
To mitigate the severity of rear-end and other collisions, Pre-Crash Systems (PCS) are being developed. These active safety systems utilize radar and/or video cameras to determine when a frontal crash, such as a front-to-back rear-end collisions, is imminent and can brake autonomously, even with no driver input. Of these PCS features, the effects of autonomous pre-crash braking are estimated. To estimate the maximum potential for injury reduction due to autonomous pre-crash braking in the striking vehicle of rear-end crashes, a methodology is presented for determining 1) the reduction in vehicle crash change in velocity (ΔV) due to PCS braking and 2) the number of injuries that could be prevented due to the reduction in collision severity. Injury reduction was only performed for belted drivers, as unbelted drivers have an unknown risk of being thrown out of position. The study was based on 1,406 rear-end striking vehicles from NASS / CDS years 1993 to 2008. PCS parameters were selected from realistic values and varied to examine the effect on system performance. PCS braking authority was varied from 0.5 G's to 0.8 G's while time to collision (TTC) was held at 0.45 seconds. TTC was then varied from 0.3 second to 0.6 seconds while braking authority was held constant at 0.6 G's. A constant braking pulse (step function) and ramp-up braking pulse were used. The study found that automated PCS braking could reduce the crash ΔV in rear-end striking vehicles by an average of 12% - 50% and avoid 0% - 14% of collisions, depending on PCS parameters. Autonomous PCS braking could potentially reduce the number of injured drivers who are belted by 19% to 57%.
Maistros, Alexander; Schneider, William H; Savolainen, Peter T
2014-06-01
Alcohol related crashes have accounted for approximately 35% of fatal crashes per year since 1994 nationwide, with approximately 30% involving impairment over the legal blood alcohol content limit of 0.08%. Educational campaigns and law enforcement efforts are two components of multi-faceted programs aimed toward reducing impaired driving. It is crucial that further research be conducted to guide the implementation of enforcement and educational programs. This research attempts to provide such guidance by examining differences in alcohol-involved crashes involving motorcycles and passenger cars. Prior safety research has shown that motorcyclists follow a significantly different culture than the average passenger car operator. These cultural differences may be reflected by differences in the contributing factors affecting crashes and the severity of the resulting injuries sustained by the driver or motorcyclist. This research is focused on single-vehicle crashes only, in order to isolate modal effects from the contribution of additional vehicles. The crash data provided for this study are from the Ohio Department of Public Safety from 2009 through 2012. The injury severity data are analysed through the development of two mixed logit models, one for motorcyclists and one for passenger car drivers. The models quantify the effects of various factors, including horizontal curves, speeds, seatbelt use, and helmet use, which indicate that the required motor skills and balance needed for proper motorcycle operation compounded with a lack of mechanical protection make motorcyclists more prone to severe injuries, particularly on curves and in collisions with roadside objects. The findings of this study have been incorporated into combined motorcycle and sober driving educational safety campaigns. The results have shown to be favorable in supporting national campaign messages with local justification and backing. Copyright © 2014 Elsevier Ltd. All rights reserved.
Safety analysis of urban arterials at the meso level.
Li, Jia; Wang, Xuesong
2017-11-01
Urban arterials form the main structure of street networks. They typically have multiple lanes, high traffic volume, and high crash frequency. Classical crash prediction models investigate the relationship between arterial characteristics and traffic safety by treating road segments and intersections as isolated units. This micro-level analysis does not work when examining urban arterial crashes because signal spacing is typically short for urban arterials, and there are interactions between intersections and road segments that classical models do not accommodate. Signal spacing also has safety effects on both intersections and road segments that classical models cannot fully account for because they allocate crashes separately to intersections and road segments. In addition, classical models do not consider the impact on arterial safety of the immediately surrounding street network pattern. This study proposes a new modeling methodology that will offer an integrated treatment of intersections and road segments by combining signalized intersections and their adjacent road segments into a single unit based on road geometric design characteristics and operational conditions. These are called meso-level units because they offer an analytical approach between micro and macro. The safety effects of signal spacing and street network pattern were estimated for this study based on 118 meso-level units obtained from 21 urban arterials in Shanghai, and were examined using CAR (conditional auto regressive) models that corrected for spatial correlation among the units within individual arterials. Results showed shorter arterial signal spacing was associated with higher total and PDO (property damage only) crashes, while arterials with a greater number of parallel roads were associated with lower total, PDO, and injury crashes. The findings from this study can be used in the traffic safety planning, design, and management of urban arterials. Copyright © 2017 Elsevier Ltd. All rights reserved.
Traumatic peripheral nerve injuries in children: epidemiology and socioeconomics.
Missios, Symeon; Bekelis, Kimon; Spinner, Robert J
2014-12-01
Despite the negative effects of peripheral nerve injuries (PNIs) on long-term population health, their true prevalence among pediatric trauma patients is under debate. The authors investigated the prevalence of PNIs among children involved in trauma and investigated associations between PNIs and several patient characteristics. The authors performed a retrospective cohort study of pediatric trauma patients who were registered in the National Trauma Data Bank from 2009 through 2011 and who fulfilled the study inclusion criteria. They used regression techniques to investigate the association of demographic and socioeconomic factors with the rate of PNIs among these patients. Of the 245,470 study patients, 50,211 were involved in motor vehicle crashes, 3380 in motorcycle crashes, 20,491 in bicycle crashes, 18,262 in pedestrian accidents, 26,294 in other crashes (mainly involving all-terrain vehicles and snowmobiles), and 126,832 in falls. The respective prevalence of PNIs was 0.66% for motor vehicle crashes, 1% for motorcycle crashes, 0.38% for bicycle crashes, 0.42% for pedestrian accidents, 0.79% for other crashes, and 0.52% for falls. Multivariate logistic regression analysis demonstrated that the following were associated with an increased incidence of PNIs: increased patient age (OR 1.10, 95% CI 1.01-1.20), higher Injury Severity Score (OR 1.10, 95% CI 1.01-1.20), elevated systolic blood pressure at arrival at the emergency room (OR 1.10, 95% CI 1.01-1.20), and increased number of trauma surgeons at the institution (OR 1.10, 95% CI 1.01-1.20). The following were associated with lower incidence of PNIs: female sex (OR 0.94, 95% CI 0.87-1.02), rural hospitals (OR 0.94, 95% CI 0.87-1.02), and urban nonteaching hospitals (OR 0.94, 95% CI 0.87-1.02). PNIs are more common than previously identified for the pediatric trauma population. These injuries are associated with older age and increased severity of the overall injury.
Characteristics of Single Vehicle Crashes with a Teen Driver in South Carolina, 2005-2008.
Shults, Ruth A; Bergen, Gwen; Smith, Tracy J; Cook, Larry; Kindelberger, John; West, Bethany
2017-09-22
Teens' crash risk is highest in the first years of independent driving. Circumstances surrounding fatal crashes have been widely documented, but less is known about factors related to nonfatal teen driver crashes. This study describes single vehicle nonfatal crashes involving the youngest teen drivers (15-17 years), compares these crashes to single vehicle nonfatal crashes among adult drivers (35-44 years) and examines factors related to nonfatal injury producing crashes for teen drivers. Police crash data linked to hospital inpatient and emergency department data for 2005-2008 from the South Carolina Crash Outcomes Data Evaluation System (CODES) were analyzed. Nonfatal, single vehicle crashes involving passenger vehicles occurring on public roadways for teen (15-17 years) drivers were compared with those for adult (35-44 years) drivers on temporal patterns and crash risk factors per licensed driver and per vehicle miles traveled. Vehicle miles traveled by age group was estimated using data from the 2009 National Household Travel Survey. Multivariable log-linear regression analysis was conducted for teen driver crashes to determine which characteristics were related to crashes resulting in a minor/moderate injury or serious injury to at least one vehicle occupant. Compared with adult drivers, teen drivers in South Carolina had 2.5 times the single vehicle nonfatal crash rate per licensed driver and 11 times the rate per vehicle mile traveled. Teen drivers were nearly twice as likely to be speeding at the time of the crash compared with adult drivers. Teen driver crashes per licensed driver were highest during the afternoon hours of 3:00-5:59 pm and crashes per mile driven were highest during the nighttime hours of 9:00-11:59 pm. In 66% of the teen driver crashes, the driver was the only occupant. Crashes were twice as likely to result in serious injury when teen passengers were present than when the teen driver was alone. When teen drivers crashed while transporting teen passengers, the passengers were >5 times more likely to all be restrained if the teen driver was restrained. Crashes in which the teen driver was unrestrained were 80% more likely to result in minor/moderate injury and 6 times more likely to result in serious injury compared with crashes in which the teen driver was restrained. Despite the reductions in teen driver crashes associated with Graduated Driver Licensing (GDL), South Carolina's teen driver crash rates remain substantially higher than those for adult drivers. Established risk factors for fatal teen driver crashes, including restraint nonuse, transporting teen passengers, and speeding also increase the risk of nonfatal injury in single vehicle crashes. As South Carolina examines strategies to further reduce teen driver crashes and associated injuries, the state could consider updating its GDL passenger restriction to either none or one passenger <21years and dropping the passenger restriction exemption for trips to and from school. Surveillance systems such as CODES that link crash data with health outcome data provide needed information to more fully understand the circumstances and consequences of teen driver nonfatal crashes and evaluate the effectiveness of strategies to improve teen driver safety. Published by Elsevier Ltd.
Analysis of factors associated with traffic injury severity on rural roads in Iran.
Kashani, Ali Tavakoli; Shariat-Mohaymany, Afshin; Ranjbari, Andishe
2012-01-01
Iran is a country with one of the highest rates of traffic crash fatality and injury, and seventy percent of these fatalities happen on rural roads. The objective of this study is to identify the significant factors influencing injury severity among drivers involved in crashes on two kinds of major rural roads in Iran: two-lane, two-way roads and freeways. According to the dataset, 213569 drivers were involved in rural road crashes in Iran, over the 3 years from 2006 to 2008. The Classification And Regression Tree method (CART) was applied for 13 independent variables, and one target variable of injury severity with 3 classes of no-injury, injury and fatality. Some of the independent variables were cause of crash, collision type, weather conditions, road surface conditions, driver's age and gender and seat belt usage. The CART model was trained by 70% of these data, and tested with the rest. It was indicated that seat belt use is the most important safety factor for two-lane, two-way rural roads, but on freeways, the importance of this variable is less. Cause of crash, also turned out to be the next most important variable. The results showed that for two-lane, two-way rural roads, "improper overtaking" and "speeding", and for rural freeways, "inattention to traffic ahead", "vehicle defect", and "movement of pedestrians, livestock and unauthorized vehicles on freeways" are the most serious causes of increasing injury severity. The analysis results revealed seat belt use, cause of crash and collision type as the most important variables influencing the injury severity of traffic crashes. To deal with these problems, intensifying police enforcement by means of mobile patrol vehicles, constructing overtaking lanes where necessary, and prohibiting the crossing of pedestrians and livestock and the driving of unauthorized vehicles on freeways are necessary. Moreover, creating a rumble strip on the two edges of roads, and paying attention to the design consistency of roads can be a helpful factor in order to prevent events such as "overturning" and improve the overall safety of freeways.
NASA Astrophysics Data System (ADS)
Gill, G.; Sakrani, T.; Cheng, W.; Zhou, J.
2017-09-01
Traffic safety is a major concern in the transportation industry due to immense monetary and emotional burden caused by crashes of various severity levels, especially the injury and fatality ones. To reduce such crashes on all public roads, the safety management processes are commonly implemented which include network screening, problem diagnosis, countermeasure identification, and project prioritization. The selection of countermeasures for potential mitigation of crashes is governed by the influential factors which impact roadway crashes. Crash prediction model is the tool widely adopted by safety practitioners or researchers to link various influential factors to crash occurrences. Many different approaches have been used in the past studies to develop better fitting models which also exhibit prediction accuracy. In this study, a crash prediction model is developed to investigate the vehicular crashes occurring at roadway segments. The spatial and temporal nature of crash data is exploited to form a spatiotemporal model which accounts for the different types of heterogeneities among crash data and geometric or traffic flow variables. This study utilizes the Poisson lognormal model with random effects, which can accommodate the yearly variations in explanatory variables and the spatial correlations among segments. The dependency of different factors linked with roadway geometric, traffic flow, and road surface type on vehicular crashes occurring at segments was established as the width of lanes, posted speed limit, nature of pavement, and AADT were found to be correlated with vehicle crashes.
The use of technology to address patterns of risk among teenage drivers.
Brovold, Shawn; Ward, Nic; Donath, Max; Simon, Stephen; Shankwitz, Craig; Creaser, Janet
2007-01-01
The crash risk of teens is high, with fatal crash rates of teen drivers higher than any other age group. New approaches to reduce teen traffic fatalities are clearly needed. A possible approach to reduce the incidence of teen driver crashes and fatalities is through the use of vehicle-based intelligent driver support systems. To be most effective, the system should address the behaviors associated with an overwhelming number of teen fatal crashes: speed, low seatbelt use, and alcohol impairment. In-vehicle technology also offers an opportunity to address the issue of inexperience through enforcement of certain Graduated Driver's License provisions. To fully understand the capability of such technologies, there should be a concerted effort to further their development, and human factors testing should take place to understand their effects on the driver. If successfully implemented, a Teen Driver Support System (TDSS), such as the one described here, could significantly decrease the number of teens killed in traffic crashes.
Ogunmuyiwa, Stella Aimiede; Gbolahan, Olalere Omoyosola; Ayantunde, Abiodun Abraham; Odewabi, Adenike Abidemi
2015-01-01
Background: Trauma remains a leading cause of maxillofacial injury globally. Changing etiological factors and patterns of maxillofacial injury continue to be reported and are largely modulated by socio-geographic and environmental factors. It is important to have an in-depth understanding of the pattern and etiology in a particular region before effective preventive measures can be developed. Aim: The aim was to evaluate the patterns, etiological factors, and management of maxillofacial injuries in Ogun state, Nigeria. Materials and Methods: A prospective descriptive cohort study of all consecutive patients that presented with maxillofacial injuries at our center between January and December 2013. Information about demographic data, types of maxillofacial and associated injury, etiology of injury, treatment received and complications were collected and analyzed. Results: Seventy patients presented with maxillofacial injury during the study period with a male to female ratio of 4:1. The age range was 9 months to 60 years with a mean of 30.11 ± standard deviation 14.97 years. Majority of the facial fractures were due to motorcycle related crashes. There were 57.1% mandibular fractures and 55.7% middle third fractures. Closed reduction with maxillo-mandibular fixation was the major method of treatment of facial fractures. Postoperative complications were observed in 11.4% of patients. Conclusion: Road traffic crashes (RTCs) remain the leading etiological factor of maxillofacial injuries in our center. Enforcement of stricter traffic regulations and possibly replacement of motorcycles with tricycles for commercial transportation may help to reduce the incidence of RTCs. PMID:25838765
Wang, Stewart C.; Bednarski, Brian; Patel, Smita; Yan, Alice; Kohoyda-Inglis, Carla; Kennedy, Theresa; Link, Elizabeth; Rowe, Stephen; Sochor, Mark; Arbabi, Saman
2003-01-01
The objective of this study was to determine the effect of differences in subcutaneous fat depth on adult injury patterns in motor vehicle collisions. Sixty-seven consecutive adult crash subjects aged 19–65 who received computed tomography of their chest, abdomen and pelvis as part of their medical evaluation and who consented to inclusion in the Crash Injury Research Engineering Network (CIREN) study were included. Subcutaneous fat was measured just lateral to the rectus abdominus muscle in a transverse section taken through the subject at the level of L4. Women had significantly greater subcutaneous fat depth than men. Increased subcutaneous fat depth was associated with significantly decreased injury severity to the abdominal region of females. A similar trend was noted in males although it did not reach statistical significance. Our findings suggest that increased subcutaneous fat may be protective against injuries by cushioning the abdominal region against injurious forces in motor vehicle collisions. PMID:12941250
Full-Scale Transport controlled Impact Demonstration
NASA Technical Reports Server (NTRS)
Hayduk, R. J. (Compiler)
1986-01-01
The controlled impact demonstration (CID) test of a transport aircraft took place on December 1, 1984, crashing at a prepared site on Rogers Dry Lakebed, Edwards Air Force Base, California. The demonstration was a setback for the antimisting kerosene (AMK) researchers. The impact conditions, considerably different from the planned scenario, exposed large quantities of degraded AMK and hydraulic fluid and caused unexpectedly hot ignition sources, bulk loss of fuel from the right wing, airflow patterns over the wings and fuselage that were untested on AMK, and fuel intrusion into the lower fuselage. The test was much more severe than planned and is generally considered to be unrepresentative of the type of survivable crash that would benefit from AMK. Ninety-seven percent of the sensors on the fuselage and wing structure, seats, dummies, restraint systems, galley, and bins were active at impact. A wealth of sensor data was collected from this once-in-a-lifetime research test. The flight data recorder experiments on board were also generally successful.
Time-varying mixed logit model for vehicle merging behavior in work zone merging areas.
Weng, Jinxian; Du, Gang; Li, Dan; Yu, Yao
2018-08-01
This study aims to develop a time-varying mixed logit model for the vehicle merging behavior in work zone merging areas during the merging implementation period from the time of starting a merging maneuver to that of completing the maneuver. From the safety perspective, vehicle crash probability and severity between the merging vehicle and its surrounding vehicles are regarded as major factors influencing vehicle merging decisions. Model results show that the model with the use of vehicle crash risk probability and severity could provide higher prediction accuracy than previous models with the use of vehicle speeds and gap sizes. It is found that lead vehicle type, through lead vehicle type, through lag vehicle type, crash probability of the merging vehicle with respect to the through lag vehicle, crash severities of the merging vehicle with respect to the through lead and lag vehicles could exhibit time-varying effects on the merging behavior. One important finding is that the merging vehicle could become more and more aggressive in order to complete the merging maneuver as quickly as possible over the elapsed time, even if it has high vehicle crash risk with respect to the through lead and lag vehicles. Copyright © 2018 Elsevier Ltd. All rights reserved.
Analysis of crash parameters and driver characteristics associated with lower limb injury.
Ye, Xin; Poplin, Gerald; Bose, Dipan; Forbes, Aaron; Hurwitz, Shepard; Shaw, Greg; Crandall, Jeff
2015-10-01
This study aims to investigate changes in frequency, risk, and patterns of lower limb injuries due to vehicle and occupant parameters as a function of vehicle model year. From the National Automotive Sampling System-Crashworthiness Data System, 10,988 observations were sampled and analyzed, representing 4.7 million belted drivers involved in frontal crashes for the years 1998-2010. A logistic regression model was developed to understand the association of sustaining knee and below knee lower limb injuries of moderate or greater severity with motor vehicle crash characteristics such as vehicle type and model years, toepan and instrument panel intrusions in addition to the occupant's age, gender, height and weight. Toepan intrusion greater than 2cm was significantly associated with an increased likelihood of injury (odds ratio: 9.10, 95% confidence interval 1.82-45.42). Females sustained a higher likelihood of distal lower limb injuries (OR: 6.83, 1.56-29.93) as compared to males. Increased mass of the driver was also found to have a positive association with injury (OR: 1.04, 1.02-1.06), while age and height were not associated with injury likelihood. Relative to passenger cars, vans exhibited a protective effect against sustaining lower limb injury (OR: 0.24, 0.07-0.78), whereas no association was shown for light trucks (OR: 1.31, 0.69-2.49) or SUVs (OR: 0.76, 0.28-2.02). To examine whether current crash testing results are representative of real-world NASS-CDS findings, data from frontal offset crash tests performed by the Insurance Institute for Highway Safety (IIHS) were examined. IIHS data indicated a decreasing trend in vehicle foot well and toepan intrusion, foot accelerations, tibia axial forces and tibia index in relation to increasing vehicle model year between the year 1995 and 2013. Over 90% of vehicles received the highest IIHS rating, with steady improvement from the upper and lower tibia index, tibia axial force and the resultant foot acceleration considering both left and right extremities. Passenger cars received the highest rating followed by SUVs and light trucks, while vans attained the lowest rating. These results demonstrate that while there has been steady improvement in vehicle crash test performance, below-knee lower extremity injuries remain the most common AIS 2+ injury in real-world frontal crashes. Copyright © 2015 Elsevier Ltd. All rights reserved.
Adverse weather conditions and fatal motor vehicle crashes in the United States, 1994-2012.
Saha, Shubhayu; Schramm, Paul; Nolan, Amanda; Hess, Jeremy
2016-11-08
Motor vehicle crashes are a leading cause of injury mortality. Adverse weather and road conditions have the potential to affect the likelihood of motor vehicle fatalities through several pathways. However, there remains a dearth of assessments associating adverse weather conditions to fatal crashes in the United States. We assessed trends in motor vehicle fatalities associated with adverse weather and present spatial variation in fatality rates by state. We analyzed the Fatality Analysis Reporting System (FARS) datasets from 1994 to 2012 produced by the National Highway Traffic Safety Administration (NHTSA) that contains reported weather information for each fatal crash. For each year, we estimated the fatal crashes that were associated with adverse weather conditions. We stratified these fatalities by months to examine seasonal patterns. We calculated state-specific rates using annual vehicle miles traveled data for all fatalities and for those related to adverse weather to examine spatial variations in fatality rates. To investigate the role of adverse weather as an independent risk factor for fatal crashes, we calculated odds ratios for known risk factors (e.g., alcohol and drug use, no restraint use, poor driving records, poor light conditions, highway driving) to be reported along with adverse weather. Total and adverse weather-related fatalities decreased over 1994-2012. Adverse weather-related fatalities constituted about 16 % of total fatalities on average over the study period. On average, 65 % of adverse weather-related fatalities happened between November and April, with rain/wet conditions more frequently reported than snow/icy conditions. The spatial distribution of fatalities associated with adverse weather by state was different than the distribution of total fatalities. Involvement of alcohol or drugs, no restraint use, and speeding were less likely to co-occur with fatalities during adverse weather conditions. While adverse weather is reported for a large number of motor vehicle fatalities for the US, the type of adverse weather and the rate of associated fatality vary geographically. These fatalities may be addressed and potentially prevented by modifying speed limits during inclement weather, improving road surfacing, ice and snow removal, and providing transit alternatives, but the impact of potential interventions requires further research.
Calibration of Airframe and Occupant Models for Two Full-Scale Rotorcraft Crash Tests
NASA Technical Reports Server (NTRS)
Annett, Martin S.; Horta, Lucas G.; Polanco, Michael A.
2012-01-01
Two full-scale crash tests of an MD-500 helicopter were conducted in 2009 and 2010 at NASA Langley's Landing and Impact Research Facility in support of NASA s Subsonic Rotary Wing Crashworthiness Project. The first crash test was conducted to evaluate the performance of an externally mounted composite deployable energy absorber under combined impact conditions. In the second crash test, the energy absorber was removed to establish baseline loads that are regarded as severe but survivable. Accelerations and kinematic data collected from the crash tests were compared to a system integrated finite element model of the test article. Results from 19 accelerometers placed throughout the airframe were compared to finite element model responses. The model developed for the purposes of predicting acceleration responses from the first crash test was inadequate when evaluating more severe conditions seen in the second crash test. A newly developed model calibration approach that includes uncertainty estimation, parameter sensitivity, impact shape orthogonality, and numerical optimization was used to calibrate model results for the second full-scale crash test. This combination of heuristic and quantitative methods was used to identify modeling deficiencies, evaluate parameter importance, and propose required model changes. It is shown that the multi-dimensional calibration techniques presented here are particularly effective in identifying model adequacy. Acceleration results for the calibrated model were compared to test results and the original model results. There was a noticeable improvement in the pilot and co-pilot region, a slight improvement in the occupant model response, and an over-stiffening effect in the passenger region. This approach should be adopted early on, in combination with the building-block approaches that are customarily used, for model development and test planning guidance. Complete crash simulations with validated finite element models can be used to satisfy crash certification requirements, thereby reducing overall development costs.
Iraeus, Johan; Lindquist, Mats
2016-10-01
Frontal crashes still account for approximately half of all fatalities in passenger cars, despite several decades of crash-related research. For serious injuries in this crash mode, several authors have listed the thorax as the most important. Computer simulation provides an effective tool to study crashes and evaluate injury mechanisms, and using stochastic input data, whole populations of crashes can be studied. The aim of this study was to develop a generic buck model and to validate this model on a population of real-life frontal crashes in terms of the risk of rib fracture. The study was conducted in four phases. In the first phase, real-life validation data were derived by analyzing NASS/CDS data to find the relationship between injury risk and crash parameters. In addition, available statistical distributions for the parameters were collected. In the second phase, a generic parameterized finite element (FE) model of a vehicle interior was developed based on laser scans from the A2MAC1 database. In the third phase, model parameters that could not be found in the literature were estimated using reverse engineering based on NCAP tests. Finally, in the fourth phase, the stochastic FE model was used to simulate a population of real-life crashes, and the result was compared to the validation data from phase one. The stochastic FE simulation model overestimates the risk of rib fracture, more for young occupants and less for senior occupants. However, if the effect of underestimation of rib fractures in the NASS/CDS material is accounted for using statistical simulations, the risk of rib fracture based on the stochastic FE model matches the risk based on the NASS/CDS data for senior occupants. The current version of the stochastic model can be used to evaluate new safety measures using a population of frontal crashes for senior occupants. Copyright © 2016 Elsevier Ltd. All rights reserved.
Aduen, Paula A; Kofler, Michael J; Sarver, Dustin E; Wells, Erica L; Soto, Elia F; Cox, Daniel J
2018-06-01
ADHD is associated with automobile crashes, traffic fatalities, and serious road trauma, but it is unclear whether this risk is (a) driven by ADHD symptoms specifically, and (b) unique to ADHD or transdiagnostic across psychiatric disabilities, such as depression, that also have concentration problems as core symptoms. The current study provides the first prospective, continuously-monitored evaluation of crash risk related to ADHD symptoms, including the first on-road comparison of ADHD with another high-prevalence psychiatric disability (depression). A probability-based sample of 3226 drivers from six U.S. sites, including subsamples with self-reported ADHD (n = 274) and depression (n = 251), consented to have their vehicles outfitted with sophisticated data acquisition technologies to continuously monitor real-world, day-to-day driving from 'engine-on to engine-off' for 1-2 years (Mean = 440 consecutive days/driver, Mean = 9528 miles/driver). Crashes and near-crashes were objectively identified via software-based algorithms and double-coded manual validation (blinded to clinical status). Miles driven, days monitored, age, gender, education, and marital status were controlled. ADHD symptoms portended 5% increased crash risk per increase in symptom severity score (IRR = 1.05). This risk corresponded to approximately 1 biennial crash and 1 annual near-crash per driver with ADHD; crash risk doubled for drivers reporting ADHD symptom severity near the sample's maximum. Analyses based on self-reported clinical status indicated similarly elevated rates for ADHD (IRR = 1.46) and depression (IRR = 1.34) that may be related, in part, to both groups' inattention/concentration symptoms. Risk was not attenuated by ADHD usual treatment, but varied according to antidepressant medication status. Previous studies have significantly underestimated the risk for traffic crashes conveyed by ADHD and depression. Copyright © 2018 Elsevier Ltd. All rights reserved.
Rizzi, Matteo; Strandroth, Johan; Kullgren, Anders; Tingvall, Claes; Fildes, Brian
2015-01-01
This study set out to evaluate the effectiveness of motorcycle antilock braking systems (ABS) in reducing real-life crashes. Since the European Parliament has voted on legislation making ABS mandatory on all new motorcycles over 125 cc from 2016, the fitment rate in Europe is likely to increase in the coming years. Though previous research has focused on mostly large displacement motorcycles, this study used police reports from Spain (2006-2009), Italy (2009), and Sweden (2003-2012) in order to analyze a wide range of motorcycles, including scooters, and compare countries with different motorcycling habits. The statistical analysis used odds ratio calculations with an induced exposure approach. Previous research found that head-on crashes were the least ABS-affected crash type and was therefore used as the nonsensitive crash type for ABS in these calculations. The same motorcycle models, with and without ABS, were compared and the calculations were carried out for each country separately. Crashes involving only scooters were further analyzed. The effectiveness of motorcycle ABS in reducing injury crashes ranged from 24% (95% confidence interval [CI], 12-36) in Italy to 29% (95% CI, 20-38) in Spain, and 34% (95% CI, 16-52) in Sweden. The reductions in severe and fatal crashes were even greater, at 34% (95% CI, 24-44) in Spain and 42% (95% CI, 23-61) in Sweden. The overall reductions of crashes involving ABS-equipped scooters (at least 250 cc) were 27% (95% CI, 12-42) in Italy and 22% (95% CI, 2-42) in Spain. ABS on scooters with at least a 250 cc engine reduced severe and fatal crashes by 31% (95% CI, 12-50), based on Spanish data alone. At this stage, there is more than sufficient scientific-based evidence to support the implementation of ABS on all motorcycles, even light ones. Further research should aim at understanding the injury mitigating effects of motorcycle ABS, possibly in combination with combined braking systems.
Viano, David C; Parenteau, Chantal S
2018-06-21
This study investigated trends in severe injury and ejection in rollover crashes involving lap-shoulder belted drivers and right-front passengers. It was conducted because of changes in 2009 to consumer information programs and regulations related to rollover protection. The data is presented by model year (MY) of the vehicle in groups from 1995-2016. NASS-CDS cases with 2010-16 MY vehicles were also evaluated to determine the crash circumstances and causes for severe injury of belted occupants in vehicles with a high strength-to-weight (SWR) roof, curtain and side airbags and other safety improvements. 1997-2015 NASS-CDS data was evaluated for severe injury and ejection of lap-shoulder belted front-outboard occupants in light vehicles. Crashes were grouped by front, side, rear and rollover. The injury and ejection data was grouped by vehicle MY: 1995-99, 2000-04, 2005-09 and 2010-16. Only drivers and right-front passengers were included if they were lap-shoulder belted and 15+ years old. Severely injured occupants were defined as those with MAIS 4-6 or fatality (MAIS 4+F). National estimates were made with weighted data using the ratio weight in NASS-CDS. All NASS-CDS electronic cases were evaluated for belted occupants with MAIS 4+F injury in rollovers involving 2010-16 MY vehicles. The crash circumstances and injuries were studied. These vehicles had high SWR roofs to meet IIHS ratings and FMVSS 216. The 1997-2015 NASS-CDS included 2,083,776 belted front occupants in rollover crashes with 24,466 (1.17%) MAIS 4+F injuries. The frequency of rollover crashes has decreased with modern vehicles (p < 0.0001). The 1995-1999 MY vehicles involved in a rollover accounted for 7.03% of all crashes (756,228/10,760,000). The corresponding proportion was 3.57% with 2010-2016 MY vehicles (81,406 v 2,282,062). The risk for MAIS 4+F was 1.325 ± 0.347% in rollover crashes with 1995-99 MY vehicles. It was 27.2% lower in 2010-16 MY vehicles at 0.964 ± 0.331% (p < 0.001). There were 42,567 (2.002%) ejections of belted occupants in rollover crashes, irrespective of injury outcome. The risk for ejection was 3.042 ± 1.44% in rollover crashes with 1995-99 MY vehicles. It was 43.6% lower in 2004-2009 MY vehicle at 1.715 ± 0.660% (p <0.001) and 83.4% lower in 2010-16 MY vehicle at 0.505 ± 0.336% (p < 0.001). There were 17 rollovers with MAIS 4+F in 2010-16 MY vehicles in NASS-CDS. Their roof strength was SWR = 4.15 ± 1.05 based on 15 vehicles. Many of the collisions involved front or side impacts and then a rollover. Four cases involved 16-30 year old drivers in extremely high-speed loss of control crashes resulting in >10 cm vertical roof deformation or substantial roof deformation based on photos. The roof strength (SWR) of 4.20 ± 1.0 was not sufficient to prevent roof deformation in these crashes. This study found a reduction in severe injury and ejection risk with modern vehicles. It indicates vehicle safety has improved in response to IIHS and NHTSA efforts to expand the array of safety requirements and increase performance so that newer models are safer than earlier ones. There has been an incremental improvement in safety by these advances.
Contributory factors to traffic crashes at signalized intersections in Hong Kong.
Wong, S C; Sze, N N; Li, Y C
2007-11-01
Efficient geometric design and signal timing not only improve operational performance at signalized intersections by expanding capacity and reducing traffic delays, but also result in an appreciable reduction in traffic conflicts, and thus better road safety. Information on the incidence of crashes, traffic flow, geometric design, road environment, and traffic control at 262 signalized intersections in Hong Kong during 2002 and 2003 are incorporated into a crash prediction model. Poisson regression and negative binomial regression are used to quantify the influence of possible contributory factors on the incidence of killed and severe injury (KSI) crashes and slight injury crashes, respectively, while possible interventions by traffic flow are controlled. The results for the incidence of slight injury crashes reveal that the road environment, degree of curvature, and presence of tram stops are significant factors, and that traffic volume has a diminishing effect on the crash risk. The presence of tram stops, number of pedestrian streams, road environment, proportion of commercial vehicles, average lane width, and degree of curvature increase the risk of KSI crashes, but the effect of traffic volume is negligible.
Cell phone use and traffic crash risk: a culpability analysis.
Asbridge, Mark; Brubacher, Jeff R; Chan, Herbert
2013-02-01
The use of a cell phone or communication device while driving is illegal in many jurisdictions, yet evidence evaluating the crash risk associated with cell phone use in naturalistic settings is limited. This article aims to determine whether cell phone use while driving increases motor vehicle crash culpability. Method Drivers involved in crashes where police reported cell phone use (n = 312) and propensity matched drivers (age, sex, suspect alcohol/drug impairment, crash type, date, time of day, geographical location) without cell phone use (n = 936) were drawn from Insurance Corporation of British Columbia Traffic Accident System data. A standardized scoring tool, modified to account for Canadian driving conditions, was used to determine crash culpability from police reports on all drivers from the crashes. The association between crash culpability and cell phone use was determined, with additional subgroup analyses based on crash severity, driver characteristics and type of licence. A comparison of crashes with vs without cell phones revealed an odds ratio of 1.70 (95% confidence interval 1.22-2.36; P = 0.002). This association was consistent after adjustment for matching variables and other covariates. Subgroup analyses demonstrated an association for male drivers, unimpaired drivers, injured and non-injured drivers, and for drivers aged between 26 and 65 years. Crash culpability was found to be significantly associated with cell phone use by drivers, increasing the odds of a culpable crash by 70% compared with drivers who did not use a cell phone. This increased risk was particularly high for middle-aged drivers.
Head injury causation scenarios for belted, rear-seated children in frontal impacts.
Bohman, Katarina; Arbogast, Kristy B; Bostrom, Ola
2011-02-01
Head injuries are the most common serious injuries sustained by children in motor vehicle crashes and are of critical importance with regard to long-term disability. There is a lack of understanding of how seat belt-restrained children sustain head injuries in frontal impacts. The aim of the study was to identify the AIS2+ head injury causation scenarios for rear-seated, belt-restrained children in frontal impacts, including the set of parameters contributing to the injury. In-depth crash investigations from two National Highway Traffic Safety Administration (NHTSA) databases, the National Automotive Sampling System-Crashworthiness Data System (NASS-CDS; 1997-2008) and the Crash Injury Research and Engineering Network (CIREN; 1996-2009), were collected and analyzed in detail. Selection criteria were all frontal impacts with principal direction of force (PDOF) of 11, 12, and 1 o'clock involving rear-seated, three-point belt-restrained, with or without booster cushion, children from 3 to 13 years with an AIS2+ head injury. Cases were analyzed using the BioTab method of injury causation assessment in order to systematically analyze the injury causation scenario for each case. There were 27 cases meeting the inclusion criteria, 19 cases with MAIS2 head injuries and 8 cases with MAIS3+ head injuries, including 2 fatalities. Three major injury causation scenarios were identified, including head contact with seatback (10 cases), head contact with side interior (7 cases,) and no evidence of head contact (9 cases). Head injuries with seatback or side interior contact typically included a PDOF greater than 10 degree (similar to the Insurance Institute for Highway Safety [IIHS] and EuroNCAP offset frontal testing) and vehicle maneuvers. For seatback contact, the vehicle's movements contributed to occupant kinematics inboard the vehicle, causing a less than optimal restraint of the torso and/or torso roll out of the shoulder belt. For side interior contact, the PDOF and/or maneuvers forced the occupant toward the side interior. The cases without evidence of head/face contact were characterized by high crash severity and accompanied by severe injuries to the thorax and spine. These data lead to increased understanding of the injury patterns and causation in this crash restraint scenario so that interventions to mitigate the burden of injury can be advanced.
Glass half-full: On-road glance metrics differentiate crashes from near-crashes in the 100-Car data.
Seppelt, Bobbie D; Seaman, Sean; Lee, Joonbum; Angell, Linda S; Mehler, Bruce; Reimer, Bryan
2017-10-01
Much of the driver distraction and inattention work to date has focused on concerns over drivers removing their eyes from the forward roadway to perform non-driving-related tasks, and its demonstrable link to safety consequences when these glances are timed at inopportune moments. This extensive literature has established, through the analyses of glance from naturalistic datasets, a clear relationship between eyes-off-road, lead vehicle closing kinematics, and near-crash/crash involvement. This paper looks at the role of driver expectation in influencing drivers' decisions about when and for how long to remove their eyes from the forward roadway in an analysis that consider the combined role of on- and off-road glances. Using glance data collected in the 100-Car Naturalistic Driving Study (NDS), near-crashes were examined separately from crashes to examine how momentary differences in glance allocation over the 25-s prior to a precipitating event can differentiate between these two distinct outcomes. Individual glance metrics of mean single glance duration (MSGD), total glance time (TGT), and glance count for off-road and on-road glance locations were analyzed. Output from the AttenD algorithm (Kircher and Ahlström, 2009) was also analyzed as a hybrid measure; in threading together on- and off-road glances over time, its output produces a pattern of glance behavior meaningful for examining attentional effects. Individual glance metrics calculated at the epoch-level and binned by 10-s units of time across the available epoch lengths revealed that drivers in near-crashes have significantly longer on-road glances, and look less frequently between on- and off- road locations in the moments preceding a precipitating event as compared to crashes. During on-road glances, drivers in near-crashes were found to more frequently sample peripheral regions of the roadway than drivers in crashes. Output from the AttenD algorithm affirmed the cumulative net benefit of longer on-road glances and of improved attention management between on- and off-road locations. The finding of longer on-road glances differentiating between safety-critical outcomes in the 100-Car NDS data underscores the importance of attention management in how drivers look both on and off the road. It is in the pattern of glances to and from the forward roadway that drivers obtained critical information necessary to inform their expectation of hazard potential to avoid a crash. This work may have important implications for attention management in the context of the increasing prevalence of in-vehicle demands as well as of vehicle automation. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.
Automated enforcement and highway safety : final report.
DOT National Transportation Integrated Search
2013-11-01
The objectives of the Automated Enforcement and Highway Safety Research study were to conduct a : literature review of national research related to the effectiveness of Red Light Camera (RLC) programs : in changing crash frequency, crash severity, cr...
Alcohol involvement in fatal traffic crashes 1998
DOT National Transportation Integrated Search
2001-03-01
This report presents estimates of alcohol involvement in fatal traffic crashes that occurred during 1998. Several comparisons of alcohol involvement for the period 1982-1998 are presented to illustrate changes and trends. The data are abstracted from...
Alcohol involvement in fatal traffic crashes 1999
DOT National Transportation Integrated Search
2001-05-01
This report presents estimates of alcohol invoelement in fatal traffic crashes that occured during 1999. Several comparisons of alcohol involvement for the period 1982-1999 are presented to illustrate changes and trends. The data are abstracted from ...
Alcohol involvement in fatal traffic crashes 1997
DOT National Transportation Integrated Search
2000-08-01
This report presents estimates of alcohol involvement in fatal traffic crashes that occurred during 1997. Several comparisons of alcohol involvement for the period 1982-1997 are presented to illustrate changes and trends. The data are abstracted from...
Data needs for tree removal crash modification factors on Arizona state highways.
DOT National Transportation Integrated Search
2016-07-01
The Arizona Department of Transportation (ADOT) Roadway Departure Safety Implementation Plan (RDSIP) has : identified tree removal as a feasible countermeasure to reduce roadway departure crash frequency or severity. : Previous ADOT work has identifi...
Incidence and crash mechanisms of aortic injury during the past decade.
Schulman, Carl I; Carvajal, Daniel; Lopez, Peter P; Soffer, Dror; Habib, Fahim; Augenstein, Jeffrey
2007-03-01
Aortic injuries were traditionally thought to be the result of severe frontal crashes. Newer data has suggested other crash types such as nearside crashes may also be important in aortic injury. We hypothesized the implementation of recent safety measures would decrease the incidence of aortic injury associated with fatal motor vehicle crashes. The autopsy reports of all traffic fatalities for motor vehicle occupants in a large urban county for the years 1993 to 2004 were examined. The demographics, impact types, safety measures used, and the presence of any aortic injury were recorded. Trends were evaluated for significance by weighted linear regression. The incidence of aortic injury associated with fatal motor vehicle crashes has remained unchanged during the past 12 years (r = 0.057, p = 0.45). There is a trend toward decreased aortic injuries associated with frontal crashes (r = 0.26, p = 0.089) but no change in aortic injuries associated with nearside or farside crashes (r = 0.053, p = 0.47), when the crash resulted in a fatality. This is despite an increase in seat belt use and increased presence of airbags during the same time period. Despite improved safety measures designed to minimize the occurrence of aortic injuries, the incidence of blunt aortic injury in fatal motor vehicle crashes has not decreased during the past decade. Although not statistically significant, there is a trend toward decreased frontal impacts in fatal motor vehicle crashes associated with aortic injuries. The nearside crash mechanism continues to play a prominent role, and efforts at improving vehicle safety should be focused on crash mechanisms as they relate to aortic injury.
af Wåhlberg, Anders; Freeman, James; Watson, Barry; Watson, Angela
2016-01-01
Background Traffic offences have been considered an important predictor of crash involvement, and have often been used as a proxy safety variable for crashes. However the association between crashes and offences has never been meta-analysed and the population effect size never established. Research is yet to determine the extent to which this relationship may be spuriously inflated through systematic measurement error, with obvious implications for researchers endeavouring to accurately identify salient factors predictive of crashes. Methodology and Principal Findings Studies yielding a correlation between crashes and traffic offences were collated and a meta-analysis of 144 effects drawn from 99 road safety studies conducted. Potential impact of factors such as age, time period, crash and offence rates, crash severity and data type, sourced from either self-report surveys or archival records, were considered and discussed. After weighting for sample size, an average correlation of r = .18 was observed over the mean time period of 3.2 years. Evidence emerged suggesting the strength of this correlation is decreasing over time. Stronger correlations between crashes and offences were generally found in studies involving younger drivers. Consistent with common method variance effects, a within country analysis found stronger effect sizes in self-reported data even controlling for crash mean. Significance The effectiveness of traffic offences as a proxy for crashes may be limited. Inclusion of elements such as independently validated crash and offence histories or accurate measures of exposure to the road would facilitate a better understanding of the factors that influence crash involvement. PMID:27128093
Case series analysis of hindfoot injuries sustained by drivers in frontal motor vehicle crashes.
Ye, Xin; Funk, James; Forbes, Aaron; Hurwitz, Shepard; Shaw, Greg; Crandall, Jeff; Freeth, Rob; Michetti, Chris; Rudd, Rodney; Scarboro, Mark
2015-09-01
Improvements to vehicle frontal crashworthiness have led to reductions in toe pan and instrument panel intrusions as well as leg, foot, and ankle loadings in standardized crash tests. Current field data, however, suggests the proportion of foot and ankle injuries sustained by drivers in frontal crashes has not decreased over the past two decades. To explain the inconsistency between crash tests results and real world lower limb injury prevalence, this study investigated the injury causation scenario for the specific hind-foot injury patterns observed in frontal vehicle crashes. Thirty-four cases with leg, foot, and ankle injuries were selected from the Crash Injury Research and Engineering Network (CIREN) database. Talus fractures were present in 20 cases, representing the most frequent hind-foot skeletal injuries observed among the reviewed cases. While axial compression was the predominant loading mechanism causing 18 injuries, 11 injured ankles involved inversion or eversion motion, and 5 involved dorsiflexion as the injury mechanism. Injured ankles of drivers were more biased towards the right aspect with foot pedals contributing to injuries in 13 of the 34 cases. Combined, the results suggest that despite recent advancement of vehicle performance in crash tests, efforts to reduce axial forces sustained in lower extremity should be prioritized. The analysis of injury mechanisms in this study could aid in crash reconstructions and the development of safety systems for vehicles. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Morgan, Richard M; Cui, Chongzhen; Digges, Kennerly H; Cao, Libo; Kan, Cing-Dao Steve
2012-01-01
This research investigated (1) what are the key attributes of the between-rail, frontal crash, (2) what are the types of object contacted, and (3) what is the type of resulting trauma. The method was to study with both weighted and in-depth case reviews of NASS-CDS crash data with direct damage between the longitudinal rails in frontal crashes. Individual case selection was limited to belted occupants in between-rail, frontal impacts of good-rated, late-model vehicles equipped with air bags.This paper evaluates the risk of trauma for drivers in cars and LTVs in between-rail, frontal crashes, and suggests the between-rail impact is more dangerous to car drivers. Using weighted data-representing 227,305 tow-away crashes-the resulting trauma to various body regions was analyzed to suggest greatest injury is to the chest, pelvis/thigh/knee/leg, and foot/ankle. This study analyzed the type of object that caused the direct damage between the rails, including small tree or post, large tree or pole, and another vehicle; and found that the struck object was most often another vehicle or a large tree/pole. Both the extent of damage and the occupant compartment intrusion were explored, and suggest that 64% of the serious injuries are associated with increasing intrusion. Individual NASS cases were reviewed to gain a deeper understanding of the mechanical particulars in the between-rail crash.
Patterns of drug use in fatal crashes.
Romano, Eduardo; Pollini, Robin A
2013-08-01
To characterize drug prevalence among fatally injured drivers, identify significant associations (i.e. day of week, time of day, age, gender), and compare findings with those for alcohol. Descriptive and logistic mixed-model regression analyses of Fatality Analysis Reporting System data. US states with drug test results for >80% of fatally injured drivers, 1998-2010. Drivers killed in single-vehicle crashes on public roads who died at the scene of the crash (n = 16 942). Drug test results, blood alcohol concentration (BAC), gender, age and day and time of crash. Overall, 45.1% of fatally injured drivers tested positive for alcohol (39.9% BAC ≥ 0.08) and 25.9% for drugs. The most common drugs present were stimulants (7.2%) and cannabinols (7.1%), followed by 'other' drugs (4.1%), multiple drugs (4.1%), narcotics (2.1%) and depressants (1.5%). Drug-involved crashes occurred with relative uniformity throughout the day while alcohol-involved crashes were more common at night (P < 0.01). The odds of testing positive for drugs varied depending upon drug class, driver characteristics, time of day and the presence of alcohol. Fatal single-vehicle crashes involving drugs are less common than those involving alcohol and the characteristics of drug-involved crashes differ, depending upon drug class and whether alcohol is present. Concerns about drug-impaired driving should not detract from the current law enforcement focus on alcohol-impaired driving. © 2013 Society for the Study of Addiction.
Robartes, Erin; Chen, T Donna
2017-07-01
This paper examines bicyclist, automobile driver, vehicle, environmental, and roadway characteristics that influence cyclist injury severity in order to determine which factors should be addressed to mitigate the worst bicyclist injuries. An ordered probit model is used to examine single bicycle-single vehicle crashes from Virginia police crash report data from 2010 to 2014. Five injury severity levels are considered: fatalities, severe injuries, minor or possible injuries, no apparent injuries, and no injury. The results of this study most notably found automobile driver intoxication to increase the probability of a cyclist fatality six fold and double the risk of a severe injury, while bicyclist intoxication increases the probability of a fatality by 36.7% and doubles the probability of severe injury. Additionally, bicycle and automobile speeds, obscured automobile driver vision, specific vehicle body types (SUV, truck, and van), vertical roadway grades and horizontal curves elevate the probability of more severe bicyclist injuries. Model results encourage consideration of methods to reduce the impact of biking and driving while intoxicated such as analysis of bicycling under the influence laws, education of drunk driving impacts on bicyclists, and separation of vehicles and bicycles on the road. Additionally, the results encourage consideration of methods to improve visibility of bicyclists and expectation of their presence on the road. Copyright © 2017 Elsevier Ltd. All rights reserved.
Classification of rollovers according to crash severity.
Digges, K; Eigen, A
2006-01-01
NASS/CDS 1995-2004 was used to classify rollovers according to severity. The rollovers were partitioned into two classes - rollover as the first event and rollover preceded by an impact with a fixed or non-fixed object. The populations of belted and unbelted were examined separately and combined. The average injury rate for the unbelted was five times that for the belted. Approximately 21% of the severe injuries suffered by belted occupants were in crashes with harmful events prior to the rollover that produced severe damage to the vehicle. This group carried a much higher injury risk than the average. A planar damage measure in addition to the rollover measure was required to adequately capture the crash severity of this population. For rollovers as the first event, approximately 1% of the serious injuries to belted occupants occurred during the first quarter-turn. Rollovers that were arrested during the 1 ( st ) quarter-turn carried a higher injury rate than average. The number of quarter-turns were grouped in various ways including the number of times the vehicle roof faces the ground (number of vehicle inversions). The number of vehicle inversions was found to be a statistically significant injury predictor for 78% of the belted and unbelted populations with MAIS 3+F injuries in rollovers. The remaining 22% required crash severity metrics in addition to the number of vehicle inversions.
Classification of Rollovers According to Crash Severity
Digges, K.; Eigen, A.
2006-01-01
NASS/CDS 1995–2004 was used to classify rollovers according to severity. The rollovers were partitioned into two classes – rollover as the first event and rollover preceded by an impact with a fixed or non-fixed object. The populations of belted and unbelted were examined separately and combined. The average injury rate for the unbelted was five times that for the belted. Approximately 21% of the severe injuries suffered by belted occupants were in crashes with harmful events prior to the rollover that produced severe damage to the vehicle. This group carried a much higher injury risk than the average. A planar damage measure in addition to the rollover measure was required to adequately capture the crash severity of this population. For rollovers as the first event, approximately 1% of the serious injuries to belted occupants occurred during the first quarter-turn. Rollovers that were arrested during the 1st quarter-turn carried a higher injury rate than average. The number of quarter-turns were grouped in various ways including the number of times the vehicle roof faces the ground (number of vehicle inversions). The number of vehicle inversions was found to be a statistically significant injury predictor for 78% of the belted and unbelted populations with MAIS 3+F injuries in rollovers. The remaining 22% required crash severity metrics in addition to the number of vehicle inversions. PMID:16968634
Fitzpatrick, Cole D; Rakasi, Saritha; Knodler, Michael A
2017-01-01
Speed is one of the most important factors in traffic safety as higher speeds are linked to increased crash risk and higher injury severities. Nearly a third of fatal crashes in the United States are designated as "speeding-related", which is defined as either "the driver behavior of exceeding the posted speed limit or driving too fast for conditions." While many studies have utilized the speeding-related designation in safety analyses, no studies have examined the underlying accuracy of this designation. Herein, we investigate the speeding-related crash designation through the development of a series of logistic regression models that were derived from the established speeding-related crash typologies and validated using a blind review, by multiple researchers, of 604 crash narratives. The developed logistic regression model accurately identified crashes which were not originally designated as speeding-related but had crash narratives that suggested speeding as a causative factor. Only 53.4% of crashes designated as speeding-related contained narratives which described speeding as a causative factor. Further investigation of these crashes revealed that the driver contributing code (DCC) of "driving too fast for conditions" was being used in three separate situations. Additionally, this DCC was also incorrectly used when "exceeding the posted speed limit" would likely have been a more appropriate designation. Finally, it was determined that the responding officer only utilized one DCC in 82% of crashes not designated as speeding-related but contained a narrative indicating speed as a contributing causal factor. The use of logistic regression models based upon speeding-related crash typologies offers a promising method by which all possible speeding-related crashes could be identified. Published by Elsevier Ltd.
Woitsch, Gernot; Sinz, Wolfgang
2014-01-01
Combination of active and passive safety systems is a future key to further improvement in vehicle safety. Autonomous braking systems are able to reduce collision speeds, and therefore severity levels significantly. Passengers change their position due to pre-impact vehicle motion, a fact, which has not yet been considered in common crash tests. For this paper, finite elements simulations of crash tests were performed to show that forward displacements due to pre-crash braking do not necessarily increase dummy load levels. So the influence of different pre-crash scenarios, all leading to equal closing speeds in the crash phase, are considered in terms of vehicle motion (pitching, deceleration) and restraint system configurations (belt load limiter, pretensioner). The influence is evaluated by dummy loads as well as contact risk between the dummy and the interior. Copyright © 2013 Elsevier Ltd. All rights reserved.
Examining the influence of aggressive driving behavior on driver injury severity in traffic crashes.
Paleti, Rajesh; Eluru, Naveen; Bhat, Chandra R
2010-11-01
In this paper, we capture the moderating effect of aggressive driving behavior while assessing the influence of a comprehensive set of variables on injury severity. In doing so, we are able to account for the indirect effects of variables on injury severity through their influence on aggressive driving behavior, as well as the direct effect of variables on injury severity. The methodology used in the paper to accommodate the moderating effect of aggressive driving behavior takes the form of two models--one for aggressive driving and another for injury severity. These are appropriately linked to obtain the indirect and direct effects of variables. The data for estimation is obtained from the National Motor Vehicle Crash Causation Study (NMVCCS). From an empirical standpoint, we consider a fine age categorization until 20 years of age when examining age effects on aggressive driving behavior and injury severity. There are several important results from the empirical analysis undertaken in the current paper based on post-crash data collection on aggressive behavior participation just prior to the crash and injury severity sustained in a crash. Young drivers (especially novice drivers between 16 and 17 years of age), drivers who are not wearing seat belt, under the influence of alcohol, not having a valid license, and driving a pick-up are found to be most likely to behave aggressively. Situational, vehicle, and roadway factors such as young drivers traveling with young passengers, young drivers driving an SUV or a pick-up truck, driving during the morning rush hour, and driving on roads with high speed limits are also found to trigger aggressive driving behavior. In terms of vehicle occupants, the safest situation from a driver injury standpoint is when there are two or more passengers in the vehicle, at least one of whom is above the age of 20 years. These and many other results are discussed, along with implications of the result for graduated driving licensing (GDL) programs. 2010 Elsevier Ltd. All rights reserved.
Cripton, Peter A; Shen, Hui; Brubacher, Jeff R; Chipman, Mary; Friedman, Steven M; Harris, M Anne; Winters, Meghan; Reynolds, Conor C O; Cusimano, Michael D; Babul, Shelina; Teschke, Kay
2015-01-01
Objective To examine the relationship between cycling injury severity and personal, trip, route and crash characteristics. Methods Data from a previous study of injury risk, conducted in Toronto and Vancouver, Canada, were used to classify injury severity using four metrics: (1) did not continue trip by bike; (2) transported to hospital by ambulance; (3) admitted to hospital; and (4) Canadian Triage and Acuity Scale (CTAS). Multiple logistic regression was used to examine associations with personal, trip, route and crash characteristics. Results Of 683 adults injured while cycling, 528 did not continue their trip by bike, 251 were transported by ambulance and 60 were admitted to hospital for further treatment. Treatment urgencies included 75 as CTAS=1 or 2 (most medically urgent), 284 as CTAS=3, and 320 as CTAS=4 or 5 (least medically urgent). Older age and collision with a motor vehicle were consistently associated with increased severity in all four metrics and statistically significant in three each (both variables with ambulance transport and CTAS; age with hospital admission; and motor vehicle collision with did not continue by bike). Other factors were consistently associated with more severe injuries, but statistically significant in one metric each: downhill grades; higher motor vehicle speeds; sidewalks (these significant for ambulance transport); multiuse paths and local streets (both significant for hospital admission). Conclusions In two of Canada's largest cities, about one-third of the bicycle crashes were collisions with motor vehicles and the resulting injuries were more severe than in other crash circumstances, underscoring the importance of separating cyclists from motor vehicle traffic. Our results also suggest that bicycling injury severity and injury risk would be reduced on facilities that minimise slopes, have lower vehicle speeds, and that are designed for bicycling rather than shared with pedestrians. PMID:25564148
A Study of Bicycle and Passenger Car Collisions Based on Insurance Claims Data
Isaksson-Hellman, Irene
2012-01-01
In Sweden, bicycle crashes are under-reported in the official statistics that are based on police reports. Statistics from hospital reports show that cyclists constitute the highest percentage of severely injured road users compared to other road user groups. However, hospital reports lack detailed information about the crash. To get a more comprehensive view, additional data are needed to accurately reflect the casualty situation for cyclists. An analysis based on 438 cases of bicycle and passenger car collisions is presented, using data collected from insurance claims. The most frequent crash situations are described with factors as to where and when collisions occur, age and gender of the involved cyclists and drivers. Information on environmental circumstances such as road status, weather- and light conditions, speedlimits and traffic environment is also included. Based on the various crash events, a total of 32 different scenarios have been categorized, and it was found that more than 75% were different kinds of intersection related situations. From the data, it was concluded that factors such as estimated impact speed and age significantly influence injury severity. The insurance claims data complement the official statistics and provide a more comprehensive view of bicycle and passenger car collisions by considering all levels of crash and injury severity. The detailed descriptions of the crash situations also provide an opportunity to find countermeasures to prevent or mitigate collisions. The results provide a useful basis, and facilitates the work of reducing the number of bicycle and passenger car collisions with serious consequences. PMID:23169111
Weaver, Ashley A; Loftis, Kathryn L; Stitzel, Joel D
2013-01-01
The lower extremity is the most frequently injured body region and knee-thigh-hip (KTH) injuries account for half of these injuries. Knee bolster air bags (KBABs) have been incorporated in some vehicles to serve as an additional restraint for the occupant's knees and reduce KTH injuries. To investigate the safety benefits of KBABs, similar frontal crashes with opposing KBAB deployment were selected from the Crash Injury Research and Engineering Network (CIREN) database. An 8-point similarity scoring algorithm was used to quantify crash and occupant similarity and select case comparisons. A total of 183 cases without a KBAB were scored for similarity to 9 KBAB cases. These similarity scores were used to select 31 final case comparisons. The effect of KBAB deployment on occupant injury patterns was investigated with a particular focus on KTH injuries. Over half of the occupants exposed to a KBAB sustained no KTH injuries and a reduction in femur fractures was observed in KBAB occupants (P = .036). However, increases in proximal tibia/fibula and foot/ankle fractures were observed in KBAB occupants (P = .022 and .002, respectively). Mildly significant decreases in pelvic fractures and Abbreviated Injury Scale (AIS) 2+ head injuries were observed in the KBAB occupants, supporting the notion that KBABs reduce forward occupant excursion (P = .094 and .055, respectively). Investigation of each case comparison yielded further insight into the reasons for injury pattern differences between cases with opposing KBAB deployment. In addition to KBAB deployment status, differences in occupant factors (age, height, and weight) and crash factors (delta V and belt use) between the cases for a particular comparison could explain variation in injury patterns. The current study presents a preliminary in-depth qualitative and quantitative assessment of KBAB safety benefits. However, further investigation is recommended to provide conclusive evidence of KBAB effectiveness.
Study of high-tension cable barriers on Michigan roadways.
DOT National Transportation Integrated Search
2014-10-01
Median-crossover crashes present the highest risk of fatality and severe injury among all collision types on : freeways. These crashes are caused by : a variety of factors, including drowsiness, driver distraction, impaired : driving, and loss of con...
Improving safety of teenage and young adult drivers in Kansas.
DOT National Transportation Integrated Search
2013-12-01
Statistics show that young drivers have higher motor vehicle crash rates compared to other age groups. This study investigated : characteristics, contributory causes, and factors which increase injury severity of young driver crashes in Kansas by com...
DOT National Transportation Integrated Search
2009-04-28
This part of the study examines the locations of high trends of severe crashes (incapacitating and fatal crashes) on multilane corridors in the state of Florida at two levels, county level and roadway level. The Geographic Information System (GIS) to...
Honeybul, Stephen; Ho, Kwok M; Lind, Christopher R P; Gillett, Grant R
2014-05-01
The goal in this study was to assess the validity of the corticosteroid randomization after significant head injury (CRASH) collaborators prediction model in predicting mortality and unfavorable outcome at 18 months in patients with severe traumatic brain injury (TBI) requiring decompressive craniectomy. In addition, the authors aimed to assess whether this model was well calibrated in predicting outcome across a wide spectrum of severity of TBI requiring decompressive craniectomy. This prospective observational cohort study included all patients who underwent a decompressive craniectomy following severe TBI at the two major trauma hospitals in Western Australia between 2004 and 2012 and for whom 18-month follow-up data were available. Clinical and radiological data on initial presentation were entered into the Web-based model and the predicted outcome was compared with the observed outcome. In validating the CRASH model, the authors used area under the receiver operating characteristic curve to assess the ability of the CRASH model to differentiate between favorable and unfavorable outcomes. The ability of the CRASH 6-month unfavorable prediction model to differentiate between unfavorable and favorable outcomes at 18 months after decompressive craniectomy was good (area under the receiver operating characteristic curve 0.85, 95% CI 0.80-0.90). However, the model's calibration was not perfect. The slope and the intercept of the calibration curve were 1.66 (SE 0.21) and -1.11 (SE 0.14), respectively, suggesting that the predicted risks of unfavorable outcomes were not sufficiently extreme or different across different risk strata and were systematically too high (or overly pessimistic), respectively. The CRASH collaborators prediction model can be used as a surrogate index of injury severity to stratify patients according to injury severity. However, clinical decisions should not be based solely on the predicted risks derived from the model, because the number of patients in each predicted risk stratum was still relatively small and hence the results were relatively imprecise. Notwithstanding these limitations, the model may add to a clinician's ability to have better-informed conversations with colleagues and patients' relatives about prognosis.
Circulation Through the Central American Seaway During the Miocene Carbonate Crash
NASA Astrophysics Data System (ADS)
Newkirk, D. R.; Martin, E. E.
2007-12-01
Changes in deep sea circulation in the Caribbean Basin were investigated in order to determine the cause of the carbonate crash in the middle to late Miocene and the impact of the shoaling of the Central American Seaway (CAS) on larger scale circulation patterns. Gateway events, such as the shoaling of the CAS, have long been associated with the reorganization of ocean circulation and dramatic climate events. The distribution of water masses in the Caribbean region was evaluated using Nd isotopes from fossil fish teeth from three ODP sites: Site 998 in the northern Caribbean Basin (3179 m water depth), Site 999 in the southern Caribbean (2897 m), and Site 846 from the eastern equatorial Pacific (3296 m). Prior to the carbonate crash in the Caribbean (14 to 12 Ma) ɛNd values increased from -6 to ~-3, while carbonate mass accumulation rates \\(MARs\\) decreased. During the crash interval ɛNd values were highly variable within the Caribbean basin with values ranging between -4.4 and 0; the highest values correlate with intervals of greatest dissolution. As carbonate MARs increased following the crash ɛNd values in the Caribbean began to decrease, reaching a value of ~-6 by 9 Ma. The carbonate crash in the eastern equatorial Pacific lags the Caribbean crash by about 0.5 Ma. Prior to the crash ɛNd values at Site 846 increased from -4 to -2. They then remained relatively steady during the crash. The radiogenic Nd values in the Caribbean basin are much higher than any values recorded in the Atlantic throughout the Cenozoic. The possibility that these values are altered by ash diagenesis in the Caribbean has been evaluated, but there is no correlation between intervals of ash deposition and radiogenic ɛNd values. However, these radiogenic values are similar to values reported for Pacific intermediate and shallow waters during the Miocene. It appears that corrosive, intermediate Pacific waters were gradually introduced into the Caribbean prior to the crash, while pulses of almost exclusively shallow to intermediate Pacific waters filled the Caribbean during the crash. This inflow of Pacific waters through the CAS has been predicted by several GCMs investigating the affects of CAS sill depths and the location of the ITCZ on Northern Component Water (NCW) production and flow directions through the CAS. Periods of enhanced NCW production correlate with intervals of more intense dissolution in the Caribbean, suggesting that aging of the water along the conveyor belt flow path from the North Atlantic to the Pacific creates more corrosive Pacific Deep Water, which then contributes to North Pacific Intermediate Water and Pacific Central Water. These corrosive waters flow southward producing more radiogenic ɛNd values and carbonate dissolution in the equatorial Pacific and Caribbean Basin. Shoaling of the CAS and a decrease in NCW combine to limit the flow of radiogenic, corrosive waters into the Caribbean. This reduction in Pacific throughflow is documented by the decreasing ɛNd values beginning at ~10 Ma at Site 998 and continues until ~5Ma as documented by ɛNd data from a ferromanganese crust located in the Straits of Florida.
Ding, Chuan; Chen, Peng; Jiao, Junfeng
2018-03-01
Although a growing body of literature focuses on the relationship between the built environment and pedestrian crashes, limited evidence is provided about the relative importance of many built environment attributes by accounting for their mutual interaction effects and their non-linear effects on automobile-involved pedestrian crashes. This study adopts the approach of Multiple Additive Poisson Regression Trees (MAPRT) to fill such gaps using pedestrian collision data collected from Seattle, Washington. Traffic analysis zones are chosen as the analytical unit. The effects of various factors on pedestrian crash frequency investigated include characteristics the of road network, street elements, land use patterns, and traffic demand. Density and the degree of mixed land use have major effects on pedestrian crash frequency, accounting for approximately 66% of the effects in total. More importantly, some factors show clear non-linear relationships with pedestrian crash frequency, challenging the linearity assumption commonly used in existing studies which employ statistical models. With various accurately identified non-linear relationships between the built environment and pedestrian crashes, this study suggests local agencies to adopt geo-spatial differentiated policies to establish a safe walking environment. These findings, especially the effective ranges of the built environment, provide evidence to support for transport and land use planning, policy recommendations, and road safety programs. Copyright © 2018 Elsevier Ltd. All rights reserved.
Motor vehicle crash-related subdural hematoma from real-world head impact data.
Urban, Jillian E; Whitlow, Christopher T; Edgerton, Colston A; Powers, Alexander K; Maldjian, Joseph A; Stitzel, Joel D
2012-12-10
Abstract Approximately 1,700,000 people sustain a traumatic brain injury (TBI) each year and motor vehicle crashes (MVCs) are a leading cause of hospitalization from TBI. Acute subdural hematoma (SDH) is a common intracranial injury that occurs in MVCs associated with high mortality and morbidity rates. In this study, SDH volume and midline shift have been analyzed in order to better understand occupant injury by correlating them to crash and occupant parameters. Fifty-seven head computed tomography (CT) scans were selected from the Crash Injury Research Engineering Network (CIREN) with Abbreviated Injury Scale (AIS) level 3+ SDH. Semi-automated methods were used to isolate the intracranial volume. SDH and additional occupant intracranial injuries were segmented across axial CT images, providing a total SDH injury volume. SDH volume was correlated to crash parameters and occupant characteristics. Results show a positive correlation between SDH volume and crash severity in near-side and frontal crashes. Additionally, the location of the resulting hemorrhage varied by crash type. Those with greater SDH volumes had significantly lower Glasgow Coma Scale (GCS) scores at the crash site in near-side crashes. Age and fracture type were found to be significant contributors to SDH volume. This study is a volumetric analysis of real world brain injuries and known MVC impacts. The results of this study demonstrate a relationship among SDH volume, crash mechanics, and occupant characteristics that provide a better understanding of the injury mechanisms of MVC-associated TBI.
Stadter, Greg; Grabowski, Jurek G; Burke, Christine; Aldaghlas, Tayseer A; Robinson, Linda; Fakhry, Samir M
2008-12-01
Side impact crashes, the most lethal type, account for 26% of all motor vehicle crashes in the United States. The purpose of this study is to delineate side impact airbag (SIAB) deployment rates, injury rates, and analyze crash factors associated with SIAB deployment and occupant injury. All passenger vehicles equipped with SIABs that were involved in a side impact crash were identified from the National Automotive Sampling System database. Crashes with multiple impacts, ejections, unbelted drivers or rollovers were excluded from the study. The outcome variables of interest were SIAB deployment and driver injury. SIAB deployment was compared in similar crashes to analyze the impact on driver's injury severity score. Other crash factors were also examined to analyze what role they play in SIAB deployment rates and injury rates, such as plane of contact, striking object and Delta-V. The data set for this study contained 247 drivers in near and far side crashes in vehicles with installed SIABs. Overall SIAB deployment was 43% in side impact crashes. A significant factor associated with both the SIAB deployment rate and the driver's injury rate was increased Delta-V. SIABs do not deploy consistently in crashes with a high Delta-V or with a lateral primary direction of force and a front plane of contact. In these two scenarios, further research is warranted on SIAB deployments. With SIAB deployment, it appears drivers are able to sustain a higher Delta-V impact without serious injury.
Kim, Taewung; Bose, Dipan; Foster, Jon; Bollapragada, Varun; Crandall, Jeff R; Clauser, Mark; Kerrigan, Jason R
2017-10-01
This study aimed to identify common patterns of pre-ballistic vehicle kinematics and roadway characteristics of real-world rollover crashes. Rollover crashes that were enrolled in the National Automotive Sampling System-Crashworthiness Data System (NASS-CDS) between the years 2000 and 2010 were analyzed. A descriptive analysis was performed to understand the characteristics of the pre-ballistic phase. Also, a frequency based pattern analysis was performed using a selection of NASS-CDS variables describing the pre-ballistic vehicle kinematics and roadway characteristics to rank common pathways of rollover crashes. Most case vehicles departed the road due to a loss of control/traction (LOC) (61%). The road departure with LOC was found to be 13.4 times more likely to occur with slippery road conditions compared to dry conditions. The vehicle was typically laterally skidding with yawing prior to a rollover (66%). Most case vehicles tripped over (82%) mostly at roadside/median (69%). The tripping force was applied to the wheels/tires (82%) from the ground (79%). The combination of these six most frequent attributes resulted in the most common scenario, which accounted for 26% of the entire cases. Large proportion of road departure with LOC (61%) implies electronic stability control (ESC) systems being an effective countermeasure for preventing single-vehicle rollover crashes. Furthermore, the correlation between the road departure with LOC and the reduced friction limit suggests the necessity of the performance evaluation of ESC under compromised road surface condition. Copyright © 2017 Elsevier Ltd. All rights reserved.
Stein, Deborah M; Kufera, Joseph A; Ho, Shiu M; Ryb, Gabriel E; Dischinger, Patricia C; O'Connor, James V; Scalea, Thomas M
2011-02-01
Motor vehicle collisions (MVCs) are the leading cause of spine and spinal cord injuries in the United States. Traumatic cervical spine injuries (CSIs) result in significant morbidity and mortality. This study was designed to evaluate both the epidemiologic and biomechanical risk factors associated with CSI in MVCs by using a population-based database and to describe occupant and crashes characteristics for a subset of severe crashes in which a CSI was sustained as represented by the Crash Injury Research Engineering Network (CIREN) database. Prospectively collected CIREN data from the eight centers were used to identify all case occupants between 1996 and November 2009. Case occupants older than 14 years and case vehicles of the four most common vehicle types were included. The National Automotive Sampling System's Crashworthiness Data System, a probability sample of all police-reported MVCs in the United States, was queried using the same inclusion criteria between 1997 and 2008. Cervical spinal cord and spinal column injuries were identified using Abbreviated Injury Scale (AIS) score codes. Data were abstracted on all case occupants, biomechanical crash characteristics, and injuries sustained. Univariate analysis was performed using a χ analysis. Logistic regression was used to identify significant risk factors in a multivariate analysis to control for confounding associations. CSIs were identified in 11.5% of CIREN case occupants. Case occupants aged 65 years or older and those occupants involved in rollover crashes were more likely to sustain a CSI. In univariate analysis of the subset of severe crashes represented by CIREN, the use of airbag and seat belt together (reference) were more protective than seat belt alone (odds ratio [OR]=1.73, 95% confidence interval [CI]=1.32-2.27) or the use of neither restraint system (OR=1.45, 95% CI=1.02-2.07). The most frequent injury sources in CIREN crashes were roof and its components (24.8%) and noncontact sources (15.5%). In multivariate analysis, age, rollover impact, and airbag-only restraint systems were associated with an increased odds of CSI. Using the population-based National Automotive Sampling System's Crashworthiness Data System data, 0.35% of occupants sustained a CSI. In univariate analysis, older age was noted to be a significant risk factor for CSI. Airbag-only restraint systems and both rollover and lateral crashes were also identified as risk factors for CSI. In addition, increasing delta v was highly associated with CSIs. In multivariate analysis, similar risk factors were noted. Of all the restraint systems, seat belt use without airbag deployment was found to be the most protective restraint system (OR=0.29, 95% CI=0.16-0.50), whereas airbag-only restraint was associated with the highest risk of CSI (OR=3.54, 95% CI=2.29-5.46). Despite advances in automotive safety, CSIs sustained in MVC continue to occur too often. Older case occupants are at an increased risk of CSI. Rollover crashes and severe crashes led to a much higher risk of CSI than other types and severity of MVCs. Seat belt use is very effective in preventing CSI, whereas airbag deployment may increase the risk of occupants sustaining a CSI. More protection for older occupants is needed and protection in both rollover and lateral crashes should remain a focus of the automotive industry. The design of airbag restraint systems should be evaluated so that they are not causative of serious injury. In addition, engineers should continue to focus on improving automotive design to minimize the risk of spinal injury to occupants in high severity crashes.
Comparison of Test and Finite Element Analysis for Two Full-Scale Helicopter Crash Tests
NASA Technical Reports Server (NTRS)
Annett, Martin S.; Horta,Lucas G.
2011-01-01
Finite element analyses have been performed for two full-scale crash tests of an MD-500 helicopter. The first crash test was conducted to evaluate the performance of a composite deployable energy absorber under combined flight loads. In the second crash test, the energy absorber was removed to establish the baseline loads. The use of an energy absorbing device reduced the impact acceleration levels by a factor of three. Accelerations and kinematic data collected from the crash tests were compared to analytical results. Details of the full-scale crash tests and development of the system-integrated finite element model are briefly described along with direct comparisons of acceleration magnitudes and durations for the first full-scale crash test. Because load levels were significantly different between tests, models developed for the purposes of predicting the overall system response with external energy absorbers were not adequate under more severe conditions seen in the second crash test. Relative error comparisons were inadequate to guide model calibration. A newly developed model calibration approach that includes uncertainty estimation, parameter sensitivity, impact shape orthogonality, and numerical optimization was used for the second full-scale crash test. The calibrated parameter set reduced 2-norm prediction error by 51% but did not improve impact shape orthogonality.
Increased inequality in mortality from road crashes among Arabs and Jews in Israel.
Magid, Avi; Leibovitch-Zur, Shalhevet; Baron-Epel, Orna
2015-01-01
Previous studies in several countries have shown that the economically disadvantaged seem to have a greater risk of being involved in a car crash. The aim of the present study was to compare rates and trends in mortality and injury from road crashes by age among the Arab and Jewish populations in Israel. Data on road crashes with casualties (2003-2011) from the Israeli Central Bureau of Statistics were analyzed. Age-adjusted road crash injury rates and mortality rates for 2003 to 2011 were calculated and time trends for each age group and population group are presented. Time trend significance was evaluated by linear regression models. Arabs in Israel are at increased risk of injury and mortality from road crashes compared to Jews. Road crash injury rates have significantly decreased in both populations over the last decade, although the rates have been persistently higher among Arabs. Road crash mortality rates have also decreased significantly in the Jewish population but not in the Arab population. This implies an increase in the disparity in mortality between Jews and Arabs. The most prominent differences in road crash injury and mortality rates between Arabs and Jews can be observed in young adults and young children. The reduction in road crashes in the last decade is a positive achievement. However, the reductions are not equal among Arabs and Jews in Israel. Therefore, an increase in the disparities in mortality from road crashes is apparent. Public health efforts need to focus specifically on decreasing road crashes in the Arab community.
DOT National Transportation Integrated Search
1994-10-01
THE RUN-OFF-ROAD COLLISION AVOIDANCE USING LVHS COUNTERMEASURES PROGRAM IS TO ADDRESS THE SINGLE VEHICLE CRASH PROBLEM THROUGH APPLICATION OF TECHNOLOGY TO PREVENT AND/OR REDUCE THE SEVERITY OF THESE CRASHES.
App-based crowd sourcing of bicycle and pedestrian conflict data : final report.
DOT National Transportation Integrated Search
2017-01-15
Most agencies and decision-makers rely on crash and crash severity (property damage only, injury or fatality) data : to assess transportation safety; however, in the context of public health where perceptions of safety may influence : the willingness...
Accuracy of AHOF400 with a moment-measuring load cell barrier.
DOT National Transportation Integrated Search
2011-06-13
Several performance measures derived from rigid : barrier crash testing have been proposed to assess : vehicle-to-vehicle crash compatibility. One such : measure, the Average Height of Force 400 (AHOF400) : [1], has been proposed to estimate the heig...
Development of an improved method for determining advisory speeds on horizontal curves.
DOT National Transportation Integrated Search
2016-07-01
Horizontal curves are an integral part of the highway alignment. However, a disproportionately high number of severe : crashes occur on them. One method transportation agencies use to reduce the number crashes at horizontal curves is the : installati...
Improving safety of teenage and young adult drivers in Kansas : [technical summary].
DOT National Transportation Integrated Search
2013-12-01
Statistics show that young drivers have higher motor vehicle crash rates compared to other age groups. This study investigated characteristics, contributory causes, and factors which increase injury severity of young driver crashes in Kansas by compa...
Temporal modeling of highway crash severity by involved person age.
DOT National Transportation Integrated Search
2012-07-01
This project consisted of three studies, each described in the following sections. Three published documents were generated; these are listed in the last section. : Study 1: Temporal Modeling of Highway Crash Counts for Senior and Non-Senior Drivers;...
Efficacies of roadway safety improvements across functional subclasses of rural two-lane highways.
Labi, Samuel
2011-08-01
Highway crash occurrence is a leading cause of unnatural deaths, and highway agencies continually seek to identify engineering measures to reduce crashes and to assess the efficacy of such measures. Most past studies on the effectiveness of roadway improvements in terms of crash reduction considered all rural two-lane sections as a single category of roads. However, it may be hypothesized that the differences in the mobility and accessibility characteristics that are reflected in (and due to) the different design standards between different functional subclasses in the rural two-lane highway system can lead to differences in efficacies of safety improvements at these subclasses. This paper investigates the efficacy of roadway improvements, in terms of crash reduction, at the various subclasses of rural two-lane highways. An empirical analysis of safety performance at each of the three subclasses of rural two-lane highways was carried out using the negative binomial modeling technique. For each subclass, crash prediction models were developed separately for the three levels of crash severity: property-damage only, injury, and fatal/injury. The crash factors that were considered include lane width, shoulder width, pavement surface friction, pavement condition, and horizontal and vertical alignments. After having developed the safety performance functions, the effectiveness (in terms of the extent of crash reduction, for different levels of crash severity) of highway safety enhancements at each highway subclass were determined using the theoretical concepts established in past literature. These enhancements include widening lanes, widening shoulders, enhancing pavement surface friction, and improving the vertical or horizontal alignment. The study found that there is empirical evidence to justify the decomposition of the family of rural two-lane roads into its constituent subclasses for purposes of analyzing the effectiveness of safety enhancement projects and thus to avoid underestimation or overestimation of benefits of safety improvements at this class of highways. Copyright © 2011 Elsevier Ltd. All rights reserved.
Kusano, Kristofer D.; Gabler, Hampton C.
2010-01-01
To mitigate the severity of rear-end and other collisions, Pre-Crash Systems (PCS) are being developed. These active safety systems utilize radar and/or video cameras to determine when a frontal crash, such as a front-to-back rear-end collisions, is imminent and can brake autonomously, even with no driver input. Of these PCS features, the effects of autonomous pre-crash braking are estimated. To estimate the maximum potential for injury reduction due to autonomous pre-crash braking in the striking vehicle of rear-end crashes, a methodology is presented for determining 1) the reduction in vehicle crash change in velocity (ΔV) due to PCS braking and 2) the number of injuries that could be prevented due to the reduction in collision severity. Injury reduction was only performed for belted drivers, as unbelted drivers have an unknown risk of being thrown out of position. The study was based on 1,406 rear-end striking vehicles from NASS / CDS years 1993 to 2008. PCS parameters were selected from realistic values and varied to examine the effect on system performance. PCS braking authority was varied from 0.5 G’s to 0.8 G’s while time to collision (TTC) was held at 0.45 seconds. TTC was then varied from 0.3 second to 0.6 seconds while braking authority was held constant at 0.6 G’s. A constant braking pulse (step function) and ramp-up braking pulse were used. The study found that automated PCS braking could reduce the crash ΔV in rear-end striking vehicles by an average of 12% – 50% and avoid 0% – 14% of collisions, depending on PCS parameters. Autonomous PCS braking could potentially reduce the number of injured drivers who are belted by 19% to 57%. PMID:21050603
Cook, Jerry L; Jones, Randall M
2011-12-01
We examined relations between young adult texting and accessing the web while driving with driving outcomes (viz. crashes and traffic citations). Our premise is that engaging in texting and accessing the web while driving is not only distracting but that these activities represent a pattern of behavior that leads to an increase in unwanted outcomes, such as crashes and citations. College students (N = 274) on 3 campuses (one in California and 2 in Utah) completed an electronic questionnaire regarding their driving experience and cell phone use. Our data indicate that 3 out of 4 (74.3%) young adults engage in texting while driving, over half on a weekly basis (51.8%), and some engage in accessing the web while driving (16.8%). Data analysis revealed a relationship between these cell phone behaviors and traffic citations and crashes. The findings support Jessor and Jessor's (1977) "problem behavior syndrome" by showing that traffic citations are related to texting and accessing the web while driving and that crashes are related to accessing the web while driving. Limitations and recommendations are discussed.
Differences in young driver crash involvement in states with varying licensure practices.
Ferguson, S A; Leaf, W A; Williams, A F; Preusser, D F
1996-03-01
Teenage driver licensing practices and the crashes of teenagers were compared in several states with differing laws and policies regarding licensure. High school seniors in Delaware, a state with laws that allow early driving and licensure, reported that they first drove on a public road, obtained a learner's permit and obtained a driver's license at younger ages than high school seniors in other northeastern states (Connecticut, New Jersey and upstate New York). State crash data indicated that Delaware and Connecticut, which allow unrestricted licensing at age 16, showed the highest rates of 16-year-old driver involvements in nonfatal and fatal injury crashes. Pennsylvania and upstate New York, which have night driving curfews for 16 year-olds, showed lower crash rates overall and much lower crash rates during their respective curfew hours. New Jersey and Nassau and Suffolk counties, where unsupervised driving by 16 year-olds is generally not allowed, showed the lowest crash rates for 16 year-olds. Graduated licensing programs that include delayed full-privilege licensure, night driving curfews, and extended periods of supervised practice driving are a possible countermeasure for the high motor vehicle crash rates of young drivers.
Differences in geometry of pedestrian crashes in daylight and darkness.
Sullivan, John M; Flannagan, Michael J
2011-02-01
Previous studies have shown that increased risk in darkness is particularly great for pedestrian crashes, suggesting that attempts to improve headlighting should focus on factors that likely influence those crashes. The current analysis was designed to provide information about how details of pedestrian crashes may differ between daylight and darkness. All pedestrian crashes that occurred in daylight or dark conditions in Michigan during 2004 were analyzed in terms of the variables included in the State of Michigan crash database. Additional analysis of the narratives and diagrams in police accident reports was performed for a subset of 400 of those crashes-200 sampled from daylight and 200 sampled from darkness. Several differences were found that appear to be related to the characteristic asymmetry of low-beam headlamps, which (in the United States) distributes more light on the passenger's side than the driver's side of the vehicle. These results provide preliminary quantification of the how the photometric differences between the right and left sides of typical headlamps may affect pedestrian crash risk. The results suggest that efforts to provide supplemental forward vehicle lighting in turns may have safety benefits for pedestrians. Copyright © 2011 Elsevier Ltd. All rights reserved.
Brand, S; Otte, D; Stübig, T; Petri, M; Ettinger, M; Mueller, C W; Krettek, C; Haasper, C; Probst, C
2013-12-01
Patients of motor vehicle crashes (MVCs) suffering burns are challenging for the rescue team and the admitting hospital. These patients often face worse outcomes than crash patients with trauma only. Our analysis of the German In-depth Accident Study (GIDAS) database researches the detailed crash mechanisms to identify potential prevention measures. We analyzed the 2011 GIDAS database comprising 14,072 MVC patients and compared individuals with (Burns) and without (NoBurns) burns. Only complete data sets were included. Patients with burns obviously resulting of air bag deployment only were not included in the Burns group. Data acquisition by an on call team of medical and technical researchers starts at the crash scene immediately after the crash and comprises technical data as well as medical information until discharge from the hospital. Statistical analysis was done by Mann-Whitney-U-test. Level of significance was p < 0.05. 14,072 MVC patients with complete data sets were included in the analysis. 99 individuals suffered burns (0.7%; group "Burns"). Demographic data and injury severity showed no statistical significant difference between the two groups of Burns and NoBurns. Injury severity was measured using the Injury Severity Score (ISS). Direct frontal impact (Burns: 48.5% vs. NoBurns: 33%; p < 0.05) and high-energy impacts as represented by delta-v (m/s) (Burns: 33.5 ± 21.4 vs. NoBurns: 25.2 ± 15.9; p < 0.05) were significantly different between groups as was mortality (Burns: 12.5% vs. NoBurns: 2.1%; p < 0.05). Type of patients' motor vehicles and type of crash opponent showed no differences. Our results show, that frontal and high-energy impacts are associated with a frequency of burns. This may serve automobile construction companies to improve the burn safety to prevent flames spreading from the motor compartment to the passenger compartment. Communities may impose speed limits in local crash hot spots. Copyright © 2013 Elsevier Ltd and ISBI. All rights reserved.
Cameron, M H; Elvik, R
2010-11-01
Nilsson (1981) proposed power relationships connecting changes in traffic speeds with changes in road crashes at various levels of injury severity. Increases in fatal crashes are related to the 4(th) power of the increase in mean speed, increases in serious casualty crashes (those involving death or serious injury) according to the 3(rd) power, and increases in casualty crashes (those involving death or any injury) according to the 2(nd) power. Increases in numbers of crash victims at cumulative levels of injury severity are related to the crash increases plus higher powers predicting the number of victims per crash. These relationships are frequently applied in OECD countries to estimate road trauma reductions resulting from expected speed reductions. The relationships were empirically derived based on speed changes resulting from a large number of rural speed limit changes in Sweden during 1967-1972. Nilsson (2004) noted that there had been very few urban speed limit changes studied to test his power model. This paper aims to test the assumption that the model is equally applicable in all road environments. It was found that the road environment is an important moderator of Nilsson's power model. While Nilsson's model appears satisfactory for rural highways and freeways, the model does not appear to be directly applicable to traffic speed changes on urban arterial roads. The evidence of monotonically increasing powers applicable to changes in road trauma at increasing injury severity levels with changes in mean speed is weak. The estimated power applicable to serious casualties on urban arterial roads was significantly less than that on rural highways, which was also significantly less than that on freeways. Alternative models linking the parameters of speed distributions with road trauma are reviewed and some conclusions reached for their use on urban roads instead of Nilsson's model. Further research is needed on the relationships between serious road trauma and urban speeds. 2010 Elsevier Ltd. All rights reserved.
Contributing factors of crash injury severity at public highway-railroad grade crossings in the U.S.
Haleem, Kirolos; Gan, Albert
2015-06-01
The Moving Ahead for Progress in the 21st Century (MAP-21) includes a separate program that supports safety improvements to reduce the number of fatalities and injuries at public highway-railroad grade crossings (HRGCs). This study identifies the significant factors affecting crash injury severity at public HRGCs in the United States. Crashes from 2009 through 2013 on 5,528 public HRGCs, extracted from the Federal Railroad Administration database, were used in the analysis. A comprehensive list of risk factors was explored. Examples include predictors related to geographic region of crash, geometry (e.g., area type and pavement marking type), railroad (e.g., warning device type and railroad class), traffic (e.g., train speed and vehicles annual average daily traffic "AADT"), highway user (e.g., driver age and gender), and environment (e.g., lighting and weather conditions). The study used the mixed logit model to better capture the complex highway user behavior at HRGCs. Female highway users were at higher risk of involvement in injuries and fatalities compared to males. Higher train speeds, very old drivers, open areas, concrete road surface types, and railroad equipment striking highway users before crash, were all found to increase the injury likelihood. On the other hand, young and middle-age drivers, non-passing of standing vehicles at HRGCs, industrial areas, and presence of warning bells were found to reduce injuries and fatalities. The mixed logit model succeeded in identifying contributing factors of crash severity at public HRGCs and potential countermeasures to reduce both fatalities and injuries are suggested. It is important to install warning bells at public HRGCs, especially at those with high number of injury and fatality crashes. Enforcement of traffic nearby HRGCs is necessary to prevent vehicles from overtaking of standing vehicles. Copyright © 2015 Elsevier Ltd. and National Safety Council. Published by Elsevier Ltd. All rights reserved.
Analyses of factors of crash avoidance maneuvers using the general estimates system.
Yan, Xuedong; Harb, Rami; Radwan, Essam
2008-06-01
Taking an effective corrective action to a critical traffic situation provides drivers an opportunity to avoid crash occurrence and minimize crash severity. The objective of this study is to investigate the relationship between the probability of taking corrective actions and the characteristics of drivers, vehicles, and driving environments. Using the 2004 GES crash database, this study classified drivers who encountered critical traffic events (identified as P_CRASH3 in the GES database) into two pre-crash groups: corrective avoidance actions group and no corrective avoidance actions group. Single and multiple logistic regression analyses were performed to identify potential traffic factors associated with the probability of drivers taking corrective actions. The regression results showed that the driver/vehicle factors associated with the probability of taking corrective actions include: driver age, gender, alcohol use, drug use, physical impairments, distraction, sight obstruction, and vehicle type. In particular, older drivers, female drivers, drug/alcohol use, physical impairment, distraction, or poor visibility may increase the probability of failing to attempt to avoid crashes. Moreover, drivers of larger size vehicles are 42.5% more likely to take corrective avoidance actions than passenger car drivers. On the other hand, the significant environmental factors correlated with the drivers' crash avoidance maneuver include: highway type, number of lanes, divided/undivided highway, speed limit, highway alignment, highway profile, weather condition, and surface condition. Some adverse highway environmental factors, such as horizontal curves, vertical curves, worse weather conditions, and slippery road surface conditions are correlated with a higher probability of crash avoidance maneuvers. These results may seem counterintuitive but they can be explained by the fact that motorists may be more likely to drive cautiously in those adverse driving environments. The analyses revealed that drivers' distraction could be the highest risk factor leading to the failure of attempting to avoid crashes. Further analyses entailing distraction causes (e.g., cellular phone use) and their possible countermeasures need to be conducted. The age and gender factors are overrepresented in the "no avoidance maneuver." A possible solution could involve the integration of a new function in the current ITS technologies. A personalized system, which could be related to the expected type of maneuver for a driver with certain characteristics, would assist different drivers with different characteristics to avoid crashes. Further crash database studies are recommended to investigate the association of drivers' emergency maneuvers such as braking, steering, or their combination with crash severity.
Perez, Miguel A; Sudweeks, Jeremy D; Sears, Edie; Antin, Jonathan; Lee, Suzanne; Hankey, Jonathan M; Dingus, Thomas A
2017-06-01
Understanding causal factors for traffic safety-critical events (e.g., crashes and near-crashes) is an important step in reducing their frequency and severity. Naturalistic driving data offers unparalleled insight into these factors, but requires identification of situations where crashes are present within large volumes of data. Sensitivity and specificity of these identification approaches are key to minimizing the resources required to validate candidate crash events. This investigation used data from the Second Strategic Highway Research Program Naturalistic Driving Study (SHRP 2 NDS) and the Canada Naturalistic Driving Study (CNDS) to develop and validate different kinematic thresholds that can be used to detect crash events. Results indicate that the sensitivity of many of these approaches can be quite low, but can be improved by selecting particular threshold levels based on detection performance. Additional improvements in these approaches are possible, and may involve leveraging combinations of different detection approaches, including advanced statistical techniques and artificial intelligence approaches, additional parameter modifications, and automation of validation processes. Copyright © 2017 Elsevier Ltd. All rights reserved.
Strayer, David L; Cooper, Joel M
2015-12-01
We address several themes that emerged in the commentaries related to our target article. First, we consider the relationship between cognitive distraction and crash risk. Second, we discuss the development of our cognitive distraction scale. Third, we weigh issues of self-regulation, appropriate baselines, and satisficing. Finally, we identify several areas where additional research is needed to refine our understanding of driver distraction and crash risk. © 2015, Human Factors and Ergonomics Society.
Zaloshnja, Eduard; Miller, Ted; Romano, Eduardo; Spicer, Rebecca
2004-05-01
This paper presents costs per US motor vehicle crash victim differentiated into many more diagnostic categories than prior estimates. These unit costs, which include the first keyed to the 1990 edition of Abbreviated Injury Scale (AIS) threat-to-life severity scores, are reported by body part, whether a fracture/dislocation was involved, and the maximum AIS score among the victim's injuries. This level of detail allows for a more accurate estimation of the social costs of motor vehicle crashes. It also allows for reliable analyses of interventions targeting narrow ranges of injuries. The paper updates the medical care data underlying the US crash costs from 1979 to 1986 to the mid 1990s and improves on prior productivity cost estimates. In addition to presenting the latest generation of crash victim costs, this paper analyzes the effects of applying injury costs classified by AIS code from the 1985 edition to injury incidence data coded with the 1990 edition of AIS. This long-standing practice results in inaccurate cost-benefit analyses that typically overestimate benefits. This problem is more acute when old published costs adjusted for inflation are used rather than the recent costs.
Real-world injury patterns associated with Hybrid III sternal deflections in frontal crash tests.
Brumbelow, Matthew L; Farmer, Charles M
2013-01-01
This study investigated the relationship between the peak sternal deflection measurements recorded by the Hybrid III 50th percentile male anthropometric test device (ATD) in frontal crash tests and injury and fatality outcomes for drivers in field crashes. ATD sternal deflection data were obtained from the Insurance Institute for Highway Safety's 64 km/h, 40 percent overlap crashworthiness evaluation tests for vehicles with seat belt crash tensioners, load limiters, and good-rated structure. The National Automotive Sampling System Crashworthiness Data System (NASS-CDS) was queried for frontal crashes of these vehicles in which the driver was restrained by a seat belt and air bag. Injury probability curves were calculated by frontal crash type using the injuries coded in NASS-CDS and peak ATD sternal deflection data. Fatality Analysis Reporting System (FARS) front-to-front crashes with exactly one driver death were also studied to determine whether the difference in measured sternal deflections for the 2 vehicles was related to the odds of fatality. For center impacts, moderate overlaps, and large overlaps in NASS-CDS, the probability of the driver sustaining an Abbreviated Injury Scale (AIS) score ≥ 3 thoracic injury, or any nonextremity AIS ≥ 3 injury, increased with increasing ATD sternal deflection measured in crash tests. For small overlaps, however, these probabilities decreased with increasing deflection. For FARS crashes, the fatally injured driver more often was in the vehicle with the lower measured deflection in crash tests (55 vs. 45%). After controlling for other factors, a 5-mm difference in measured sternal deflections between the 2 vehicles was associated with a fatality odds ratio of 0.762 for the driver in the vehicle with the greater deflection (95% confidence interval = 0.373, 1.449). Restraint systems that reduce peak Hybrid III sternal deflection in a moderate overlap crash test are beneficial in real-world crashes with similar or greater overlap but likely have a disbenefit in crashes with small overlap. This may occur because belt-force limiters employed to control deflections allow excursion that could produce contact with interior vehicle components in small overlaps, given the more oblique occupant motion and potential inboard movement of the air bag. Although based on a limited number of cases, this interpretation is supported by differences in skeletal fracture locations among drivers in crashes with different overlaps. Current restraint systems could be improved by designs that reduce sternal deflection in moderate and large overlap crashes without increasing occupant excursion in small overlap crashes.
Side Impact Regulatory Trends, Crash Environment and Injury Risk in the USA.
Prasad, Priya; Dalmotas, Dainius; Chouinard, Aline
2015-11-01
Light duty vehicles in the US are designed to meet and exceed regulatory standards, self-imposed industry agreements and safety rating tests conducted by NHTSA and IIHS. The evolution of side impact regulation in the US from 1973 to 2015 is discussed in the paper along with two key industry agreements in 2003 affecting design of restraint systems and structures for side impact protection. A combination of all the above influences shows that vehicles in the US are being designed to more demanding and comprehensive requirements than in any other region of the world. The crash environment in the US related to side impacts was defined based on data in the nationally representative crash database NASS. Crash environment factors, including the distribution of cars, light trucks and vans (LTV's), and medium-to-heavy vehicles (MHV's) in the fleet, and the frequency of their interactions with one another in side impacts, were considered. Other factors like, crash severity in terms of closing velocity between two vehicles involved in crash, gender and age of involved drivers in two-vehicle and single vehicle crashes, were also examined. Injury risks in side impacts to drivers and passengers were determined in various circumstances such as near-side, far-side, and single vehicle crashes as a function of crash severity, in terms of estimated closing speed or lateral delta-V. Also injury risks in different pairs of striking and struck cars and LTV's, were estimated. A logistic regression model for studying injury risks in two vehicle crashes was developed. The risk factors included in the model include case and striking vehicles, consisting of cars, SUV's, vans, and pickup trucks, delta-V, damage extent, occupant proximity to the impact side, age and gender of the occupant, and belt use. Results show that car occupants make up the vast majority of serious-to-fatally injured occupants. Injury rates of car occupants in two-vehicle collision are highest when the car is struck by a pickup and lowest when struck by a car. This was the case across all lateral delta-V ranges. Additionally, near-side injury rates are substantially higher than those in far-side impacts.
Cost and benefit estimates of partially-automated vehicle collision avoidance technologies.
Harper, Corey D; Hendrickson, Chris T; Samaras, Constantine
2016-10-01
Many light-duty vehicle crashes occur due to human error and distracted driving. Partially-automated crash avoidance features offer the potential to reduce the frequency and severity of vehicle crashes that occur due to distracted driving and/or human error by assisting in maintaining control of the vehicle or issuing alerts if a potentially dangerous situation is detected. This paper evaluates the benefits and costs of fleet-wide deployment of blind spot monitoring, lane departure warning, and forward collision warning crash avoidance systems within the US light-duty vehicle fleet. The three crash avoidance technologies could collectively prevent or reduce the severity of as many as 1.3 million U.S. crashes a year including 133,000 injury crashes and 10,100 fatal crashes. For this paper we made two estimates of potential benefits in the United States: (1) the upper bound fleet-wide technology diffusion benefits by assuming all relevant crashes are avoided and (2) the lower bound fleet-wide benefits of the three technologies based on observed insurance data. The latter represents a lower bound as technology is improved over time and cost reduced with scale economies and technology improvement. All three technologies could collectively provide a lower bound annual benefit of about $18 billion if equipped on all light-duty vehicles. With 2015 pricing of safety options, the total annual costs to equip all light-duty vehicles with the three technologies would be about $13 billion, resulting in an annual net benefit of about $4 billion or a $20 per vehicle net benefit. By assuming all relevant crashes are avoided, the total upper bound annual net benefit from all three technologies combined is about $202 billion or an $861 per vehicle net benefit, at current technology costs. The technologies we are exploring in this paper represent an early form of vehicle automation and a positive net benefit suggests the fleet-wide adoption of these technologies would be beneficial from an economic and social perspective. Copyright © 2016 Elsevier Ltd. All rights reserved.
Impact of travel patterns and driving behavior on crash involvement.
DOT National Transportation Integrated Search
1983-07-21
This study was conducted to obtain statistically valid data on a variety of highway safety issues, such as attitudes toward drunk driving, use of safety belts and child safety seats, and to establish data regarding driving patterns. The study design ...
DOT National Transportation Integrated Search
2013-08-01
Roadway safety continues to be a major national : concern, with federal, state, and other : authorities striving to reduce crashes and their : associated costs in terms of fatalities, severe : injuries, property damage, and traffic delays. : Accordin...
DOT National Transportation Integrated Search
1995-09-05
The Run-Off-Road Collision Avoidance Using IVHS Countermeasures program is to address the single vehicle crash problem through application of technology to prevent and/or reduce the severity of these crashes. : This report documents the RORSIM comput...
DOT National Transportation Integrated Search
2013-05-01
Involvement in road traffic crashes as vehicle occupants is a leading cause of death and serious injury among children. The : objective of this study was to investigate child safety restraint-use characteristics and crash-severity factors in order to...
Potential Crash Reduction Benefits of Safety Improvement Projects Part A : Shoulder Rumble Strips
DOT National Transportation Integrated Search
2012-06-01
This research provides a comprehensive evaluation of the safety benefits of shoulder rumble strips in rural highways in Idaho. The effectiveness of shoulder rumble strips in reducing the number and severity of run-off-the-road (ROR) crashes was exami...
Potential Crash Reduction Benefits of Safety Improvement Projects - Part A : Shoulder Rumble Strips
DOT National Transportation Integrated Search
2012-06-01
This research provides a comprehensive evaluation of the safety benefits of shoulder rumble strips in rural highways in Idaho. The effectiveness of shoulder rumble strips in reducing the number and severity of run-off-the-road (ROR) crashes was exami...
DOT National Transportation Integrated Search
1995-08-01
INTELLIGENT VEHICLE INITIATIVE OR IVI : THE RUN-OFF-ROAD COLLISION AVOIDANCE USING IVHS COUNTERMEASURES PROGRAM IS TO ADDRESS THE SINGLE VEHICLE CRASH PROBLEM THROUGH APPLICATION OF TECHNOLOGY TO PREVENT AND/OR REDUCE THE SEVERITY OF THESE CRASHES. :...
Run-Off-Road Collision Avoidance Countermeasures Using IVHS Countermeasures: Task 3, Volume 1
DOT National Transportation Integrated Search
1995-08-23
The Run-Off-Road Collision Avoidance Using IVHS Countermeasures program is to address the single vehicle crash problem through application of technology to prevent and/or reduce the severity oi these crashes. This report describes the findings of the...
Run-Off-Road Collision Avoidance Countermeasures Using IVHS Countermeasures Task 3 - Volume 2
DOT National Transportation Integrated Search
1995-08-23
The Run-Off-Road Collision Avoidance Using IVHS Countermeasures program is to address the single vehicle crash problem through application of technology to prevent and/or reduce the severity of these crashes. : This report describes the findings of t...
Wrong-way driving crashes on French divided roads.
Kemel, Emmanuel
2015-02-01
The objective of divided roads is to increase users' safety by posting unidirectional traffic flows. It happens however that drivers proceed in the wrong direction, endangering themselves as well as other users. The crashes caused by wrong-way drivers are generally spotlighted by the media and call for public intervention. This paper proposes a characterization of wrong-way driving crashes occurring on French divided road on the 2008-2012 period. The objective is to identify the factors that delineate between wrong-way driving crashes and other crashes. Building on the national injury road crash database, 266 crashes involving a wrong-way driver were identified. Their characteristics (related to timing, location, vehicle and driver) are compared to those of the 22,120 other crashes that occurred on the same roads over the same period. The comparison relies on descriptive statistics, completed by a logistic regression. Wrong-way driving crashes are rare but severe. They are more likely to occur during night hours and on non-freeway roads than other crashes. Wrong-way drivers are older, more likely to be intoxicated, to be locals, to drive older vehicles, mainly passenger cars without passengers, than other drivers. The differences observed across networks can help prioritizing public intervention. Most of the identified WW-driving factors deal with cognitive impairment. Therefore, the specific countermeasures such as alternative road signs should be designed for and tested on cognitively impaired drivers. Nevertheless, WW-driving factors are also risk factors for other types of crashes (e.g. elderly driving, drunk driving and age of the vehicle). This suggests that, instead of (or in addition to) developing WW-driving specific countermeasures, managing these risk factors would help reducing a larger number of crashes. Copyright © 2014 Elsevier Ltd. All rights reserved.
Opportunities for crash and injury reduction: A multiharm approach for crash data analysis.
Mallory, Ann; Kender, Allison; Moorhouse, Kevin
2017-05-29
A multiharm approach for analyzing crash and injury data was developed for the ultimate purpose of getting a richer picture of motor vehicle crash outcomes for identifying research opportunities in crash safety. Methods were illustrated using a retrospective analysis of 69,597 occupant cases from NASS CDS from 2005 to 2015. Occupant cases were analyzed by frequency and severity of outcome: fatality, injury by Abbreviated Injury Scale (AIS), number of cases, attributable fatality, disability, and injury costs. Comparative analysis variables included precrash scenario, impact type, and injured body region. Crash and injury prevention opportunities vary depending on the search parameters. For example, occupants in rear-end crash scenarios were more frequent than in any other precrash configuration, yet there were significantly more fatalities and serious injury cases in control loss, road departure, and opposite direction crashes. Fatality is most frequently associated with head and thorax injury, and disability is primarily associated with extremity injury. Costs attributed to specific body regions are more evenly distributed, dominated by injuries to the head, thorax, and extremities but with contributions from all body regions. Though AIS 3+ can be used as a single measure of harm, an analysis based on multiple measures of harm gives a much more detailed picture of the risk presented by a particular injury or set of crash conditions. The developed methods represent a new approach to crash data mining that is expected to be useful for the identification of research priorities and opportunities for reduction of crashes and injuries. As the pace of crash safety improvement accelerates with innovations in both active and passive safety, these techniques for combining outcome measures for insights beyond fatality and serious injury will be increasingly valuable.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wenzel, Tom
2012-08-01
NHTSA recently completed a logistic regression analysis updating its 2003 and 2010 studies of the relationship between vehicle mass and US fatality risk per vehicle mile traveled (VMT). The new study updates the previous analyses in several ways: updated FARS data from 2002 to 2008 for MY00 to MY07 vehicles are used; induced exposure data from police reported crashes in several additional states are added; a new vehicle category for car-based crossover utility vehicles (CUVs) and minivans is created; crashes with other light-duty vehicles are divided into two groups based on the crash partner vehicle’s weight, and a category formore » all other fatal crashes is added; and new control variables for new safety technologies and designs, such as electronic stability controls (ESC), side airbags, and methods to meet voluntary agreement to improve light truck compatibility with cars, are included.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wenzel, Tom
2011-09-01
NHTSA recently completed a logistic regression analysis updating its 2003 and 2010 studies of the relationship between vehicle mass and US fatality risk per vehicle mile traveled (VMT). The new study updates the previous analyses in several ways: updated FARS data from 2002 to 2008 for MY00 to MY07 vehicles are used; induced exposure data from police reported crashes in several additional states are added; a new vehicle category for car-based crossover utility vehicles (CUVs) and minivans is created; crashes with other light-duty vehicles are divided into two groups based on the crash partner vehicle’s weight, and a category formore » all other fatal crashes is added; and new control variables for new safety technologies and designs, such as electronic stability controls (ESC), side airbags, and methods to meet voluntary agreement to improve light truck compatibility with cars, are included.« less
Empirical calibration of a roadside hazardousness index for Spanish two-lane rural roads.
Pardillo-Mayora, José M; Domínguez-Lira, Carlos A; Jurado-Piña, Rafael
2010-11-01
Crash records and roadside data from Spanish two-lane rural roads were analyzed to study the effect of roadside configuration on safety. Four indicators were used to characterize the main roadside features that have an influence on the consequences of roadway departures: roadside slope, non-traversable obstacles distance from the roadway edge, safety barrier installation, and alignment. Based on the analysis of the effect of roadside configuration on the frequency and severity of run-off-road injury crashes, a categorical roadside hazardousness scale was defined. Cluster analysis was applied to group the combinations of the four indicators into categories with homogeneous effects on run-off-road injury crashes frequency and severity. As a result a 5-level Roadside Hazardousness Index (RHI) was defined. RHI can be used as reference to normalize the collection of roadside safety related information. The index can also be used as variable for inclusion of roadside condition information in multivariate crash prediction models. 2010 Elsevier Ltd. All rights reserved.
Effects of legislative reform to reduce drunken driving and alcohol-related traffic fatalities.
Hingson, R W; Howland, J; Levenson, S
1988-01-01
From 1980 through 1985, considerable progress was made across the Nation in reducing drunken driving and fatal automobile crashes. More than 400 chapters of local citizen groups concerned with reducing drunken driving were formed. New media coverage, measured in number of stories, increased fiftyfold from 1980 to 1984. More than 500 legislative reforms were passed. All States now have adopted a legal drinking age of 21. Many also adopted criminal and administrative per se laws and instituted penalty increases for drunken driving. By 1985, the total number of fatal crashes declined to 39,168, a decrease of 6,116, or 16 percent, from the 1980 level of 45,284. Single-vehicle fatal crashes occurring at night, those most likely to involve alcohol, declined by 20 percent, with 3,674 fewer crashes in 1985 than in 1980. Among teenage drivers, declines in fatal crashes were steeper: Fatal crashes decreased 26 percent, and single-vehicle night fatal crashes were down 34 percent. After 1984, however, the number of new citizen groups established and the number of stories appearing in the media began to decline. In 1986, after decreasing for several years, the number of fatal crashes rose 5 percent, and single-vehicle night fatal crashes rose 7 percent, up 1,060 from 1985. Among teenage drivers, the increase in single-vehicle night fatal crashes was even higher, up 17 percent. In 1987, single-vehicle night fatal crashes declined slightly but still remained higher than in 1983, 1984, or 1985.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3141962
Best Practices for Crash Modeling and Simulation
NASA Technical Reports Server (NTRS)
Fasanella, Edwin L.; Jackson, Karen E.
2002-01-01
Aviation safety can be greatly enhanced by the expeditious use of computer simulations of crash impact. Unlike automotive impact testing, which is now routine, experimental crash tests of even small aircraft are expensive and complex due to the high cost of the aircraft and the myriad of crash impact conditions that must be considered. Ultimately, the goal is to utilize full-scale crash simulations of aircraft for design evaluation and certification. The objective of this publication is to describe "best practices" for modeling aircraft impact using explicit nonlinear dynamic finite element codes such as LS-DYNA, DYNA3D, and MSC.Dytran. Although "best practices" is somewhat relative, it is hoped that the authors' experience will help others to avoid some of the common pitfalls in modeling that are not documented in one single publication. In addition, a discussion of experimental data analysis, digital filtering, and test-analysis correlation is provided. Finally, some examples of aircraft crash simulations are described in several appendices following the main report.
Warner, Jennifer; Hurwitz, David S; Monsere, Christopher M; Fleskes, Kayla
2017-07-01
A right-hook crash is a crash between a right-turning motor vehicle and an adjacent through-moving bicycle. At signalized intersections, these crashes can occur during any portion of the green interval when conflicting bicycles and vehicles are moving concurrently. The objective of this research was to evaluate the effectiveness of four types of engineering countermeasures - regulatory signage, intersection pavement marking, smaller curb radius, and protected intersection design - at modifying driver behaviors that are known contributing factors in these crashes. This research focused on right-hook crashes that occur during the latter stage of the circular green indication at signalized intersections with a shared right-turn and through lane. Changes in driver performance in response to treatments were measured in a high-fidelity driving simulator. Twenty-eight participants each completed 22 right-turn maneuvers. A partially counterbalanced experimental design exposed drivers to critical scenarios, which had been determined in a previous experiment. For each turn, driver performance measures, including visual attention, crash avoidance, and potential crash severity, were collected. A total of 75 incidents (47 near-collisions and 28 collisions) were observed during the 616 right turns. All treatments had some positive effect on measured driver performance with respect to the right-turn vehicle conflicts. Further work is required to map the magnitude of these changes in driver performance to crash-based outcomes. Copyright © 2017 Elsevier Ltd. All rights reserved.
Dezman, Zachary; de Andrade, Luciano; Vissoci, Joao Ricardo; El-Gabri, Deena; Johnson, Abree; Hirshon, Jon Mark; Staton, Catherine A.
2017-01-01
Introduction Road traffic injuries are a leading killer of youth (aged 15–29) and are projected to be the 7th leading cause of death by 2030. To better understand road traffic crash locations and characteristics in the city of Baltimore, we used police and census data, to describe the epidemiology, hotspots, and modifiable risk factors involved to guide further interventions. Materials and methods Data on all crashes in Baltimore City from 2009 to 2013 were made available from the Maryland Automated Accident Reporting System. Socioeconomic data collected by the US CENSUS 2010 were obtained. A time series analysis was conducted using an ARIMA model. We analyzed the geographical distribution of traffic crashes and hotspots using exploratory spatial data analysis and spatial autocorrelation. Spatial regression was performed to evaluate the impact of socioeconomic indicators on hotspots. Results In Baltimore City, between 2009 and 2013, there were a total of 100,110 crashes reported, with 1% of crashes considered severe. Of all crashes, 7% involved vulnerable road users and 12% had elderly or youth involvement. Reasons for crashes included: distracted driving (31%), speeding (6%), and alcohol or drug use (5%). After 2010, we observed an increasing trend in all crashes especially from March to June. Distracted driving then youth and elderly drivers were consistently the highest risk factors over time. Multivariate spatial regression model including socioeconomic indicators and controlling for age, gender and population size did not show a distinct predictor of crashes explaining only 20% of the road crash variability, indicating crashes are not geographically explained by socioeconomic indicators alone. Conclusion In Baltimore City, road traffic crashes occurred predominantly in the high density center of the city, involved distracted driving and extremes of age with an increase in crashes from March to June. There was no association between socioeconomic variables where crashes occurred and hotspots. In depth analysis of how modifiable risk factors are impacted by geospatial characteristics and the built environment is warranted in Baltimore to tailor interventions. PMID:27614672
Dezman, Zachary; de Andrade, Luciano; Vissoci, Joao Ricardo; El-Gabri, Deena; Johnson, Abree; Hirshon, Jon Mark; Staton, Catherine A
2016-11-01
Road traffic injuries are a leading killer of youth (aged 15-29) and are projected to be the 7th leading cause of death by 2030. To better understand road traffic crash locations and characteristics in the city of Baltimore, we used police and census data, to describe the epidemiology, hotspots, and modifiable risk factors involved to guide further interventions. Data on all crashes in Baltimore City from 2009 to 2013 were made available from the Maryland Automated Accident Reporting System. Socioeconomic data collected by the US CENSUS 2010 were obtained. A time series analysis was conducted using an ARIMA model. We analyzed the geographical distribution of traffic crashes and hotspots using exploratory spatial data analysis and spatial autocorrelation. Spatial regression was performed to evaluate the impact of socioeconomic indicators on hotspots. In Baltimore City, between 2009 and 2013, there were a total of 100,110 crashes reported, with 1% of crashes considered severe. Of all crashes, 7% involved vulnerable road users and 12% had elderly or youth involvement. Reasons for crashes included: distracted driving (31%), speeding (6%), and alcohol or drug use (5%). After 2010, we observed an increasing trend in all crashes especially from March to June. Distracted driving then youth and elderly drivers were consistently the highest risk factors over time. Multivariate spatial regression model including socioeconomic indicators and controlling for age, gender and population size did not show a distinct predictor of crashes explaining only 20% of the road crash variability, indicating crashes are not geographically explained by socioeconomic indicators alone. In Baltimore City, road traffic crashes occurred predominantly in the high density center of the city, involved distracted driving and extremes of age with an increase in crashes from March to June. There was no association between socioeconomic variables where crashes occurred and hotspots. In depth analysis of how modifiable risk factors are impacted by geospatial characteristics and the built environment is warranted in Baltimore to tailor interventions. Copyright © 2016 Elsevier Ltd. All rights reserved.
The role of conspicuity in preventing bicycle crashes involving a motor vehicle
Woodward, Alistair; Ameratunga, Shanthi
2015-01-01
Background: Bicycle use, despite its proven health and other benefits, is rarely part of everyday travel for many people due to the perceived risk of injury from collision crashes. This article investigated the role of physical vs. attention conspicuity in preventing bicycle crashes involving a motor vehicle in New Zealand. Methods: The Taupo Bicycle Study involved 2590 adult cyclists recruited in 2006 (43.1% response rate) and followed for bicycle crash outcomes through linkage to four national databases. A composite measure of physical conspicuity was created using latent class analysis based on the use of fluorescent colours, lights and reflective materials, and the main colour of top, helmet and bike frame. Attention conspicuity was assessed based on regional differences in travel patterns and the amount of riding in a bunch. Cox regression modelling for repeated events was performed with multivariate adjustments. Results: During a median follow-up period of 6.4 years, 162 participants experienced 187 bicycle–motor vehicle crashes. The crash risk was not predicted by the four latent classes identified and the amount of bunch riding but was higher in Auckland, the region with the lowest level of bicycle use relative to car use. In subgroup analyses, compared to other latent classes, the most physically conspicuous group had a higher risk in Auckland but a lower risk in other regions. Conclusion: Conspicuity aids may not be effective in preventing bicycle–motor vehicle crashes in New Zealand, particularly in Auckland, where attention conspicuity is low. PMID:25085469
Morgan, Richard M.; Cui, Chongzhen; Digges, Kennerly H.; Cao, Libo; Kan, Cing-Dao (Steve)
2012-01-01
This research investigated (1) what are the key attributes of the between-rail, frontal crash, (2) what are the types of object contacted, and (3) what is the type of resulting trauma. The method was to study with both weighted and in-depth case reviews of NASS-CDS crash data with direct damage between the longitudinal rails in frontal crashes. Individual case selection was limited to belted occupants in between-rail, frontal impacts of good-rated, late-model vehicles equipped with air bags. This paper evaluates the risk of trauma for drivers in cars and LTVs in between-rail, frontal crashes, and suggests the between-rail impact is more dangerous to car drivers. Using weighted data—representing 227,305 tow-away crashes—the resulting trauma to various body regions was analyzed to suggest greatest injury is to the chest, pelvis/thigh/knee/leg, and foot/ankle. This study analyzed the type of object that caused the direct damage between the rails, including small tree or post, large tree or pole, and another vehicle; and found that the struck object was most often another vehicle or a large tree/pole. Both the extent of damage and the occupant compartment intrusion were explored, and suggest that 64% of the serious injuries are associated with increasing intrusion. Individual NASS cases were reviewed to gain a deeper understanding of the mechanical particulars in the between-rail crash. PMID:23169135
Stephan, Karen L; Newstead, Stuart V
2014-01-01
Modeling crash risk in urban areas is more complicated than in rural areas due to the complexity of the environment and the difficulty obtaining data to fully characterize the road and surrounding environment. Knowledge of factors that impact crash risk and severity in urban areas can be used for countermeasure development and the design of risk assessment tools for practitioners. This research aimed to identify the characteristics of the road and roadside, surrounding environment, and sociodemographic factors associated with single-vehicle crash (SVC) frequency and severity in complex urban environments, namely, strip shopping center road segments. A comprehensive evidence-based list of data required for measuring the influence of the road, roadside, and other factors on crash risk was developed. The data included a broader range of factors than those traditionally considered in accident prediction models. One hundred and forty-two strip shopping segments located on arterial roads in metropolitan Melbourne, Australia, were identified. Police-reported casualty data were used to determine how many SVC occurred on the segments between 2005 and 2009. Data describing segment characteristics were collected from a diverse range of sources; for example, administrative government databases (traffic volume, speed limit, pavement condition, sociodemographic data, liquor licensing), detailed maps, on-line image sources, and digital images of arterial roads collected for the Victorian state road authority. Regression models for count data were used to identify factors associated with SVC frequency. Logistic regression was used to determine factors associated with serious and fatal outcomes. One hundred and seventy SVC occurred on the 142 selected road segments during the 5-year study period. A range of factors including traffic exposure, road cross section (curves, presence of median), road type, requirement for sharing the road with other vehicle types (trams and bicycles), roadside poles, and local amenities were associated with SVC frequency. A different set of risk factors was associated with the odds of a crash leading to a severe outcome: segment length, road cross section (curves, carriageway width), pavement condition, local amenities and vehicle, and driver factors. The presence of curves was the only factor associated with both SVC frequency and severity. A range of risk factors were associated with SVC frequency and severity in complex urban areas (metropolitan shopping strips), including traditionally studied characteristics such as traffic density and road design but also less commonly studied characteristics such as local amenities. Future behavioral research is needed to further investigate how and why these factors change the risk and severity of crashes before effective countermeasures can be developed.
Bahouth, George; Graygo, Jill; Digges, Kennerly; Schulman, Carl; Baur, Peter
2014-01-01
The objectives of this study are to (1) characterize the population of crashes meeting the Centers for Disease Control and Prevention (CDC)-recommended 20% risk of Injury Severity Score (ISS)>15 injury and (2) explore the positive and negative effects of an advanced automatic crash notification (AACN) system whose threshold for high-risk indications is 10% versus 20%. Binary logistic regression analysis was performed to predict the occurrence of motor vehicle crash injuries at both the ISS>15 and Maximum Abbreviated Injury Scale (MAIS) 3+ level. Models were trained using crash characteristics recommended by the CDC Committee on Advanced Automatic Collision Notification and Triage of the Injured Patient. Each model was used to assign the probability of severe injury (defined as MAIS 3+ or ISS>15 injury) to a subset of NASS-CDS cases based on crash attributes. Subsequently, actual AIS and ISS levels were compared with the predicted probability of injury to determine the extent to which the seriously injured had corresponding probabilities exceeding the 10% and 20% risk thresholds. Models were developed using an 80% sample of NASS-CDS data from 2002 to 2012 and evaluations were performed using the remaining 20% of cases from the same period. Within the population of seriously injured (i.e., those having one or more AIS 3 or higher injuries), the number of occupants whose injury risk did not exceed the 10% and 20% thresholds were estimated to be 11,700 and 18,600, respectively, each year using the MAIS 3+ injury model. For the ISS>15 model, 8,100 and 11,000 occupants sustained ISS>15 injuries yet their injury probability did not reach the 10% and 20% probability for severe injury respectively. Conversely, model predictions suggested that, at the 10% and 20% thresholds, 207,700 and 55,400 drivers respectively would be incorrectly flagged as injured when their injuries had not reached the AIS 3 level. For the ISS>15 model, 87,300 and 41,900 drivers would be incorrectly flagged as injured when injury severity had not reached the ISS>15 injury level. This article provides important information comparing the expected positive and negative effects of an AACN system with thresholds at the 10% and 20% levels using 2 outcome metrics. Overall, results suggest that the 20% risk threshold would not provide a useful notification to improve the quality of care for a large number of seriously injured crash victims. Alternately, a lower threshold may increase the over triage rate. Based on the vehicle damage observed for crashes reaching and exceeding the 10% risk threshold, we anticipate that rescue services would have been deployed based on current Public Safety Answering Point (PSAP) practices.
Virtual Design Method for Controlled Failure in Foldcore Sandwich Panels
NASA Astrophysics Data System (ADS)
Sturm, Ralf; Fischer, S.
2015-12-01
For certification, novel fuselage concepts have to prove equivalent crashworthiness standards compared to the existing metal reference design. Due to the brittle failure behaviour of CFRP this requirement can only be fulfilled by a controlled progressive crash kinematics. Experiments showed that the failure of a twin-walled fuselage panel can be controlled by a local modification of the core through-thickness compression strength. For folded cores the required change in core properties can be integrated by a modification of the fold pattern. However, the complexity of folded cores requires a virtual design methodology for tailoring the fold pattern according to all static and crash relevant requirements. In this context a foldcore micromodel simulation method is presented to identify the structural response of a twin-walled fuselage panels with folded core under crash relevant loading condition. The simulations showed that a high degree of correlation is required before simulation can replace expensive testing. In the presented studies, the necessary correlation quality could only be obtained by including imperfections of the core material in the micromodel simulation approach.
Burst fractures of the lumbar spine in frontal crashes.
Kaufman, Robert P; Ching, Randal P; Willis, Margaret M; Mack, Christopher D; Gross, Joel A; Bulger, Eileen M
2013-10-01
In the United States, major compression and burst type fractures (>20% height loss) of the lumbar spine occur as a result of motor vehicle crashes, despite the improvements in restraint technologies. Lumbar burst fractures typically require an axial compressive load and have been known to occur during a non-horizontal crash event that involve high vertical components of loading. Recently these fracture patterns have also been observed in pure horizontal frontal crashes. This study sought to examine the contributing factors that would induce an axial compressive force to the lumbar spine in frontal motor vehicle crashes. We searched the National Automotive Sampling System (NASS, 1993-2011) and Crash Injury Research and Engineering Network (CIREN, 1996-2012) databases to identify all patients with major compression lumbar spine (MCLS) fractures and then specifically examined those involved in frontal crashes. National trends were assessed based on weighted NASS estimates. Using a case-control study design, NASS and CIREN cases were utilized and a conditional logistic regression was performed to assess driver and vehicle characteristics. CIREN case studies and biomechanical data were used to illustrate the kinematics and define the mechanism of injury. During the study period 132 NASS cases involved major compression lumbar spine fractures for all crash directions. Nationally weighted, this accounted for 800 cases annually with 44% of these in horizontal frontal crashes. The proportion of frontal crashes resulting in MCLS fractures was 2.5 times greater in late model vehicles (since 2000) as compared to 1990s models. Belted occupants in frontal crashes had a 5 times greater odds of a MCLS fracture than those not belted, and an increase in age also greatly increased the odds. In CIREN, 19 cases were isolated as horizontal frontal crashes and 12 of these involved a major compression lumbar burst fracture primarily at L1. All were belted and almost all occurred in late model vehicles with belt pretensioners and buckets seats. Major compression burst fractures of the lumbar spine in frontal crashes were induced via a dynamic axial force transmitted to the pelvis/buttocks into the seat cushion/pan involving belted occupants in late model vehicles with increasing age as a significant factor. Copyright © 2013 Elsevier Ltd. All rights reserved.
49 CFR 350.103 - What is the purpose of this part?
Code of Federal Regulations, 2013 CFR
2013-10-01
... motor carrier, CMV, and driver safety to support a safe and efficient transportation system by— (a) Making targeted investments to promote safe CMV transportation, including transportation of passengers... number and severity of CMV crashes and fatalities resulting from such crashes; (c) Adopting and enforcing...
49 CFR 350.103 - What is the purpose of this part?
Code of Federal Regulations, 2014 CFR
2014-10-01
... motor carrier, CMV, and driver safety to support a safe and efficient transportation system by— (a) Making targeted investments to promote safe CMV transportation, including transportation of passengers... number and severity of CMV crashes and fatalities resulting from such crashes; (c) Adopting and enforcing...
DOT National Transportation Integrated Search
1994-10-28
The Run-Off-Road Collision Avoidance Using IVHS Countermeasures program is to address the single vehicle crash problem through application of technology to prevent and/or reduce the severity of these crashes. This report describes and documents the a...
DOT National Transportation Integrated Search
1994-10-01
THE RUN-OFF-ROAD COLLISION AVOIDANCE USING IVHS COUNTERMEASURES PROGRAM IS TO ADDRESS THE SINGLE VEHICLE CRASH PROBLEM THROUGH APPLICATION OF TECHNOLOGY TO PREVENT AND/OR REDUCE THE SEVERITY OF THESE CRASHES. : THIS REPORT DESCRIBES AND DOCUMENTS ...
DOT National Transportation Integrated Search
1995-06-01
THE RUN-OFF-ROAD COLLISION AVOIDANCE USING IVHS COUNTERMEASURES PROGRAM IS TO ADDRESS THE SINGLE VEHICLE CRASH PROBLEM THROUGH APPLICATION OF TECHNOLOGY TO PREVENT AND/OR REDUCE THE SEVERITY OF THESE CRASHES. : THIS REPORT DESCRIBES AND DOCUMENTS ...
DOT National Transportation Integrated Search
1995-09-01
THE RUN-OFF-ROAD COLLISION AVOIDANCE USING IVHS COUNTERMEASURES PROGRAM IS TO ADDRESS THE SINGLE VEHICLE CRASH PROBLEM THROUGH APPLICATION OF TECHNOLOGY TO PREVENT AND/OR REDUCE THE SEVERITY OF THESE CRASHES. : THIS REPORT DOCUMENTS THE RORSIM COM...
DOT National Transportation Integrated Search
1994-10-28
The Run-Off-Road Collision Avoidance Using IVHS Countermeasures program is to address the single vehicle crash problem through application of technology to prevent and/or reduce the severity of these crashes. This report contains a summary of data us...
DOT National Transportation Integrated Search
1997-04-01
The purpose of this catalog is to inspire the development of new applications : for linked data that support efforts to reduce death, disability, severity, and : health care costs related to motor vehicle crashes. The document is divided into : three...
Gorucu, Serap; Murphy, Dennis; Kassab, Cathy
2017-01-01
All Terrain Vehicles on public roadways become major risk factors for the motorists. To compare characteristics of crashes and injury severity related to single vehicle (SV) and multi-vehicle (MV) All-Terrain Vehicle (ATV) roadway crashes in Pennsylvania, USA. Data on ATV crashes occurring on public roads during the years 2010-2013 was obtained from the Pennsylvania Department of Transportation (PennDOT) and analyzed. Almost two-thirds of the incidents were single-vehicle incidents. Single-ATV incidents have a greater risk for incapacitating injury to drivers than do multi-vehicle ATV incidents. Other factors that increase risk for incapacitating injury in SV crashes include being male, being a driver, alcohol/drug involvement, hitting a fixed object, and the incidents in non-daylight hours. For MV ATV incidents, head on and rear-end crashes and drivers who had alcohol/drug involvement were the two major incapacitating injury risk factors. This study has enabled us to better understand roadway ATV incidents, characteristics of SV and MV ATV crashes, and the incapacitating injury risks in both SV and MV crash incidents. Our study suggests that road safety and public health programs should focus on the users' knowledge on laws regarding ATV usage on public roadways.
Effects of BMI on the risk and frequency of AIS 3+ injuries in motor-vehicle crashes.
Rupp, Jonathan D; Flannagan, Carol A C; Leslie, Andrew J; Hoff, Carrie N; Reed, Matthew P; Cunningham, Rebecca M
2013-01-01
Determine the effects of BMI on the risk of serious-to-fatal injury (Abbreviated Injury Scale ≥ 3 or AIS 3+) to different body regions for adults in frontal, nearside, farside, and rollover crashes. Multivariate logistic regression analysis was applied to a probability sample of adult occupants involved in crashes generated by combining the National Automotive Sampling System (NASS-CDS) with a pseudoweighted version of the Crash Injury Research and Engineering Network database. Logistic regression models were applied to weighted data to estimate the change in the number of occupants with AIS 3+ injuries if no occupants were obese. Increasing BMI increased risk of lower-extremity injury in frontal crashes, decreased risk of lower-extremity injury in nearside impacts, increased risk of upper-extremity injury in frontal and nearside crashes, and increased risk of spine injury in frontal crashes. Several of these findings were affected by interactions with gender and vehicle type. If no occupants in frontal crashes were obese, 7% fewer occupants would sustain AIS 3+ upper-extremity injuries, 8% fewer occupants would sustain AIS 3+ lower-extremity injuries, and 28% fewer occupants would sustain AIS 3+ spine injuries. Results of this study have implications on the design and evaluation of vehicle safety systems. Copyright © 2013 The Obesity Society.
Drinking and driving behavior at stop signs and red lights.
Wan, Jingyan; Wu, Changxu; Zhang, Yiqi; Houston, Rebecca J; Chen, Chang Wen; Chanawangsa, Panya
2017-07-01
Alcohol is one of the principal risk factors for motor vehicle crashes. One factor that contributes to vehicle crashes is noncompliance with stop signs and red lights. The present experiment investigated the effects of alcohol and drinking patterns on driving behavior at stop signs and red lights. 28 participants participated in drinking and simulated driving sessions during which they received a moderate dose of alcohol (0.08% BAC) or a placebo. Simulated driving tasks measured participants' driving performance at stop signs and red lights in response to each dose. Results suggested that alcohol impaired the driver control of speed and direction and prolonged their simple and complex reaction time, which were exhibited by impaired speed and lateral control, longer reaction time when the lights turned yellow, and lower deceleration towards stop signs and red lights. Visual degradation may also occur under alcohol intake. It was also suggested that alcohol impaired non-binge drinkers more severely. To be specific, higher acceleration was observed in impaired non-binge drinkers. Copyright © 2017 Elsevier Ltd. All rights reserved.
Dawson, Jeffrey D.; Bair, Elizabeth; Askan, Nazan; Sewell, Kelly; Tippin, Jon; Rizzo, Matthew
2017-01-01
Summary In naturalistic studies, Global Positioning System (GPS) data and date/time stamps can link driver exposure to specific environments (e.g., road types, speed limits, night driving, etc.), providing valuable context for analyzing critical events, such as crashes, near crashes, and breaches of accelerometer limits. In previous work, we showed how to automate this contextualization, using GPS data obtained at 1 Hz and merging this with Geographic Information Systems (GIS) databases maintained by the Iowa Department of Transportation (DOT). Here we further demonstrate our methods by analyzing data from 80 drivers with obstructive sleep apnea (OSA) and 48 controls, and comparing the two groups with respect to several factors of interest. The majority of comparisons found no difference between groups, suggesting similar patterns of exposures to driving environments in OSA and control drivers. However, OSA drivers appeared to spend slightly more time on roads with annual traffic counts of 500–10,000 and less time driving on wider highways, during twilight, and on roads with 10,000–25,000 annual traffic counts. PMID:29629434
Hao, Wei; Daniel, Janice
2016-01-01
Previous studies on crash modeling at highway-rail grade crossings were aimed at exploring the factors that are likely to increase the crash frequencies at highway-rail grade crossings. In recent years, modeling driver's injury severity at highway-rail grade crossings has received interest. Because there were substantial differences among different weather conditions for driver's injury severity, this study attempts to explore the impact of weather influence on driver injury at highway-rail grade crossing. Utilizing the most recent 10 years (2002-2011) of highway-rail grade crossing accident data, this study applied a mixed logit model to explore the determinants of driver injury severity under different weather conditions at highway-rail grade crossing. Analysis results indicate that drivers' injury severity at highway-rail grade crossings is strongly different for different weather conditions. It was found that the factors significantly impacting driver injury severity at highway-rail grade crossings include motor vehicle speed, train speed, driver's age, gender, area type, lighting condition, highway pavement, traffic volume, and time of day. The findings of this study indicate that crashes are more prevalent if vehicle drivers are driving at high speed or the oncoming trains are high speed. Hence, a reduction in speed limit during inclement weather conditions could be particularly effective in moderating injury severity, allowing more reaction time for last-minute maneuvering and braking in moments before impacts. In addition, inclement weather-related crashes were more likely to occur in open areas and highway-rail grade crossings without pavement and lighting. Paved highway-rail grade crossings with installation of lights could be particularly effective in moderating injury severity.
Lord, Dominique; Guikema, Seth D; Geedipally, Srinivas Reddy
2008-05-01
This paper documents the application of the Conway-Maxwell-Poisson (COM-Poisson) generalized linear model (GLM) for modeling motor vehicle crashes. The COM-Poisson distribution, originally developed in 1962, has recently been re-introduced by statisticians for analyzing count data subjected to over- and under-dispersion. This innovative distribution is an extension of the Poisson distribution. The objectives of this study were to evaluate the application of the COM-Poisson GLM for analyzing motor vehicle crashes and compare the results with the traditional negative binomial (NB) model. The comparison analysis was carried out using the most common functional forms employed by transportation safety analysts, which link crashes to the entering flows at intersections or on segments. To accomplish the objectives of the study, several NB and COM-Poisson GLMs were developed and compared using two datasets. The first dataset contained crash data collected at signalized four-legged intersections in Toronto, Ont. The second dataset included data collected for rural four-lane divided and undivided highways in Texas. Several methods were used to assess the statistical fit and predictive performance of the models. The results of this study show that COM-Poisson GLMs perform as well as NB models in terms of GOF statistics and predictive performance. Given the fact the COM-Poisson distribution can also handle under-dispersed data (while the NB distribution cannot or has difficulties converging), which have sometimes been observed in crash databases, the COM-Poisson GLM offers a better alternative over the NB model for modeling motor vehicle crashes, especially given the important limitations recently documented in the safety literature about the latter type of model.
[Motor vehicle crash fatalities at 30 days in Spain].
Pérez, Katherine; Pérez, Catherine; Cirera, Eva; Borrell, Carme; Plasencia, Antoni
2006-01-01
To assess level of fulfillment and utility of the hospital discharge register (HDR) as a complementary source of information for estimating the number of deaths at 30 days due to motor vehicle crashes in Spain. It is a cross-sectional study were we compared the number of people injured due to motor vehicle crashes hospitalised in a public hospital (HDR), in Spain during 2001, with the number of people severely injured or killed due to motor vehicle crashes reported by the police database (Dirección General de Tráfico, DGT) for the same year. A descriptive analysis was carried out by age, sex and region (Autonomous Community), as well as an estimation of the percentage of under-reporting of deaths by the DGT based on two assumptions. Police reported 27,272 severe injuries and 4,811 deaths during first 24 hours after the crash and after applying a fatality adjustment factor estimated 706 more deaths up to 30 days after the crash. The HDR reported 40,174 urgent hospitalisations. Of these, 1,099 died during the day of hospitalisation or within the following 30 days. The police only notified 68% of all cases that required hospitalisation. According to the number of deaths reported by police and contrasted with hospital register, estimations of the number of deaths at 30 days made by police could represent a level of under-reporting of between 3% and 6.6%, depending on the assumption considered. This study showed that the HDR is an information source that complements police statistics and is useful to estimate the number of deaths and non-fatal injuries due to motor vehicle crashes in Spain.
Thompson, J P; Baldock, M R J; Mathias, J L; Wundersitz, L N
2013-01-01
Motor vehicle crashes involving rural drivers aged 75 years and over are more than twice as likely to result in a serious or fatal injury as those involving their urban counterparts. The current study examined some of the reasons for this using a database of police-reported crashes (2004-2008) to identify the environmental (lighting, road and weather conditions, road layout, road surface, speed limit), driver (driver error, crash type), and vehicle (vehicle age) factors that are associated with the crashes of older rural drivers. It also determined whether these same factors are associated with an increased likelihood of serious or fatal injury in younger drivers for whom frailty does not contribute to the resulting injury severity. A number of environmental (i.e., undivided, unsealed, curved and inclined roads, and areas with a speed limit of 100km/h or greater) and driver (i.e., collision with a fixed object and rolling over) factors were more frequent in the crashes of older rural drivers and additionally associated with increased injury severity in younger drivers. Moreover, when these environmental factors were entered into a logistic regression model to predict whether older drivers who were involved in crashes did or did not sustain a serious or fatal injury, it was found that each factor independently increased the likelihood of a serious or fatal injury. Changes, such as the provision of divided and sealed roads, greater protection from fixed roadside objects, and reduced speed limits, appear to be indicated in order to improve the safety of the rural driving environment for drivers of all ages. Additionally, older rural drivers should be encouraged to reduce their exposure to these risky circumstances. Copyright © 2012 Elsevier Ltd. All rights reserved.
Statistical Characteristics of Wrong-Way Driving Crashes on Illinois Freeways.
Zhou, Huaguo; Zhao, Jiguang; Pour-Rouholamin, Mahdi; Tobias, Priscilla A
2015-01-01
Driving the wrong way on freeways, namely wrong-way driving (WWD), has been found to be a major concern for more than 6 decades. The purpose of this study was to identify characteristics of this type of crash as well as to rank the locations/interchanges according to their vulnerability to WWD entries. The WWD crash data on Illinois freeways were statistically analyzed for a 6-year time period (2004 to 2009) from 3 aspects: crash, vehicle, and person. The temporal distributions, geographical distributions, roadway characteristics, and crash locations were analyzed for WWD crashes. The driver demographic information, physical condition, and injury severity were analyzed for wrong-way drivers. The vehicle characteristics, vehicle operation, and collision results were analyzed for WWD vehicles. A method was brought about to identify wrong-way entry points that was then used to develop a relative-importance technique and rank different interchange types in terms of potential WWD incidents. The findings revealed that a large proportion of WWD crashes occurred during the weekend from midnight to 5 a.m. Approximately 80% of WWD crashes were located in urban areas and nearly 70% of wrong-way vehicles were passenger cars. Approximately 58% of wrong-way drivers were driving under the influence (DUI). Of those, nearly 50% were confirmed to be impaired by alcohol, about 4% were impaired by drugs, and more than 3% had been drinking. The analysis of interchange ranking found that compressed diamond interchanges, single point diamond interchanges (SPDIs), partial cloverleaf interchanges, and freeway feeders had the highest wrong-way crash rates (wrong-way crashes per 100 interchanges per year). The findings of this study call for more attention to WWD crashes from different aspects such as driver age group, time of day, day of week, and DUI drivers. Based on the analysis results of WWD distance, the study explained why a 5-mile radius of WWD crash location should be studied for WWD fatal crashes with unknown entry points.
Consideration of driver home county prohibition and alcohol-related vehicle crashes.
Schulte Gary, Sarah Lynn; Aultman-Hall, Lisa; McCourt, Matt; Stamatiadis, Nick
2003-09-01
This study examines the characteristics of alcohol-related crashes in wet versus dry counties in the state of Kentucky, USA and incorporates the location of driver residences through use of geographic information system (GIS) analysis. Between 1991 and 1997, 39344 alcohol-related crashes by Kentucky residents on Kentucky State roads were reported. The location of the crash and the home ZIP code from the driver's address were used to consider distance from home in the GIS. Analysis of the crash data revealed that a similar proportion of crashes in wet and dry counties are alcohol-related but that a higher proportion of dry counties residents are involved in an alcohol-related crash. However, when the distance from home variable is considered, several results suggest that dry county residents may be driving further when consuming alcohol. In part due to the rural nature of dry counties, drivers from dry counties have both alcohol-related and non-alcohol related crashes farther from their homes than residents from wet counties. Alcohol-related crashes by dry county residents in wet counties are the greatest average distance from home while crashes by wet county residents in wet counties are the smallest average distance. Drivers from dry counties over 21 years of age have alcohol-related crashes significantly farther from home than those under 21 who would not legally be admitted to drinking establishments in the wet counties. Furthermore, residents from dry counties that do not border wet counties have alcohol-related crashes on average farther from home than the border county residents. These last three results provide circumstantial evidence that some dry county drivers may be driving to wet counties to consume alcohol thus increasing impaired driving exposure. In conclusion, by considering crash location and driver residence, these findings indicate that county-level prohibition is not necessarily effective in improving highway safety.
Curry, Allison E.; Pfeiffer, Melissa R.; Myers, Rachel K.; Durbin, Dennis R.; Elliott, Michael R.
2014-01-01
Traditional methods for determining crash responsibility—most commonly moving violation citations—may not accurately characterize at-fault status among crash-involved drivers given that: (1) issuance may vary by factors that are independent of fault (e.g., driver age, gender), and (2) these methods do not capture driver behaviors that are not illegal but still indicative of fault. We examined the statistical implications of using moving violations to determine crash responsibility in young driver crashes by comparing it with a method based on crash-contributing driver actions. We selected all drivers in police-reported passenger-vehicle crashes (2010–2011) that involved a New Jersey driver <21 years old (79,485 drivers < age 21, 61,355 drivers ≥ age 21.) For each driver, crash responsibility was determined from the crash report using two alternative methods: (1) issuance of a moving violation citation; and (2) presence of a driver action (e.g., failure to yield, inattention). Overall, 18% of crash-involved drivers were issued a moving violation while 50% had a driver action. Only 32.2% of drivers with a driver action were cited for a moving violation. Further, the likelihood of being cited given the presence of a driver action was higher among certain driver subgroups—younger drivers, male drivers, and drivers in single-vehicle and more severe crashes. Specifically among young drivers, those driving at night, carrying peer passengers, and having a suspended or no license were more often cited. Conversely, fatally-injured drivers were almost never cited. We also demonstrated that using citation data may lead to statistical bias in the characterization of at-fault drivers and of quasi-induced exposure measures. Studies seeking to accurately determine crash responsibility should thoughtfully consider the potential sources of bias that may result from using legal culpability methods. For many studies, determining driver responsibility via the identification of driver actions may yield more accurate characterizations of at-fault drivers. PMID:24398139
Kaplan, Sigal; Prato, Carlo Giacomo
2012-01-01
The current study focuses on the propensity of drivers to engage in crash avoidance maneuvers in relation to driver attributes, critical events, crash characteristics, vehicles involved, road characteristics, and environmental conditions. The importance of avoidance maneuvers derives from the key role of proactive and state-aware road users within the concept of sustainable safety systems, as well as from the key role of effective corrective maneuvers in the success of automated in-vehicle warning and driver assistance systems. The analysis is conducted by means of a mixed logit model that represents the selection among 5 emergency lateral and speed control maneuvers (i.e., "no avoidance maneuvers," "braking," "steering," "braking and steering," and "other maneuvers) while accommodating correlations across maneuvers and heteroscedasticity. Data for the analysis were retrieved from the General Estimates System (GES) crash database for the year 2009 by considering drivers for which crash avoidance maneuvers are known. The results show that (1) the nature of the critical event that made the crash imminent greatly influences the choice of crash avoidance maneuvers, (2) women and elderly have a relatively lower propensity to conduct crash avoidance maneuvers, (3) drowsiness and fatigue have a greater negative marginal effect on the tendency to engage in crash avoidance maneuvers than alcohol and drug consumption, (4) difficult road conditions increase the propensity to perform crash avoidance maneuvers, and (5) visual obstruction and artificial illumination decrease the probability to carry out crash avoidance maneuvers. The results emphasize the need for public awareness campaigns to promote safe driving style for senior drivers and warning about the risks of driving under fatigue and distraction being comparable to the risks of driving under the influence of alcohol and drugs. Moreover, the results suggest the need to educate drivers about hazard perception, designing a forgiving infrastructure within a sustainable safety systems, and rethinking in-vehicle collision warning systems. Future research should address the effectiveness of crash avoidance maneuvers and joint modeling of maneuver selection and crash severity.
DOT National Transportation Integrated Search
2015-04-01
Safety at intersections is of significant interest to transportation professionals due to the large number of : possible conflicts that occur at those locations. In particular, rural intersections have been recognized as : one of the most hazardous l...
Traffic accidents involving fatigue driving and their extent of casualties.
Zhang, Guangnan; Yau, Kelvin K W; Zhang, Xun; Li, Yanyan
2016-02-01
The rapid progress of motorization has increased the number of traffic-related casualties. Although fatigue driving is a major cause of traffic accidents, the public remains not rather aware of its potential harmfulness. Fatigue driving has been termed as a "silent killer." Thus, a thorough study of traffic accidents and the risk factors associated with fatigue-related casualties is of utmost importance. In this study, we analyze traffic accident data for the period 2006-2010 in Guangdong Province, China. The study data were extracted from the traffic accident database of China's Public Security Department. A logistic regression model is used to assess the effect of driver characteristics, type of vehicles, road conditions, and environmental factors on fatigue-related traffic accident occurrence and severity. On the one hand, male drivers, trucks, driving during midnight to dawn, and morning rush hours are identified as risk factors of fatigue-related crashes but do not necessarily result in severe casualties. Driving at night without street-lights contributes to fatigue-related crashes and severe casualties. On the other hand, while factors such as less experienced drivers, unsafe vehicle status, slippery roads, driving at night with street-lights, and weekends do not have significant effect on fatigue-related crashes, yet accidents associated with these factors are likely to have severe casualties. The empirical results of the present study have important policy implications on the reduction of fatigue-related crashes as well as their severity. Copyright © 2015 Elsevier Ltd. All rights reserved.
Sleep deficiency and motor vehicle crash risk in the general population: a prospective cohort study.
Gottlieb, Daniel J; Ellenbogen, Jeffrey M; Bianchi, Matt T; Czeisler, Charles A
2018-03-20
Insufficient sleep duration and obstructive sleep apnea, two common causes of sleep deficiency in adults, can result in excessive sleepiness, a well-recognized cause of motor vehicle crashes, although their contribution to crash risk in the general population remains uncertain. The objective of this study was to evaluate the relation of sleep apnea, sleep duration, and excessive sleepiness to crash risk in a community-dwelling population. This was a prospective observational cohort study nested within the Sleep Heart Health Study, a community-based study of the health consequences of sleep apnea. The participants were 1745 men and 1456 women aged 40-89 years. Sleep apnea was measured by home polysomnography and questionnaires were used to assess usual sleep duration and daytime sleepiness. A follow-up questionnaire 2 years after baseline ascertained driving habits and motor vehicle crash history. Logistic regression analysis was used to examine the relation of sleep apnea and sleep duration at baseline to the occurrence of motor vehicle crashes during the year preceding the follow-up visit, adjusting for relevant covariates. The population-attributable fraction of motor vehicle crashes was estimated from the sample proportion of motor vehicle crashes and the adjusted odds ratios for motor vehicle crash within each exposure category. Among 3201 evaluable participants, 222 (6.9%) reported at least one motor vehicle crash during the prior year. A higher apnea-hypopnea index (p < 0.01), fewer hours of sleep (p = 0.04), and self-reported excessive sleepiness (p < 0.01) were each significantly associated with crash risk. Severe sleep apnea was associated with a 123% increased crash risk, compared to no sleep apnea. Sleeping 6 hours per night was associated with a 33% increased crash risk, compared to sleeping 7 or 8 hours per night. These associations were present even in those who did not report excessive sleepiness. The population-attributable fraction of motor vehicle crashes was 10% due to sleep apnea and 9% due to sleep duration less than 7 hours. Sleep deficiency due to either sleep apnea or insufficient sleep duration is strongly associated with motor vehicle crashes in the general population, independent of self-reported excessive sleepiness.
Child Passengers Injured in Motor Vehicle Crashes
Romano, Eduardo; Kelley-Baker, Tara
2015-01-01
Introduction—During 2010, 171,000 children aged 0-14 were injured in motor vehicle crashes. Despite the severity of the problem, research has been limited, and most of what we know about these children emanates from fatal crash databases. Method—Using information from the General Estimates System, this effort examines the occurrence of non-fatal crashes among children aged 0-14 over the last decade. Results—We found about 1% of the non-injured children in the file had been driven by a driver who was positive for alcohol. This percentage climbed to about 2% among children who had suffered injuries. Compared with the proportion of alcohol-positive drivers at the time of the crash, the proportion of drivers who sped or failed to obey a traffic signal were significantly higher. Practical Applications—The finding that drinking and driving with children did not decrease over time questions the adequacy of the extant child endangerment laws. PMID:25662876
Improving the crashworthiness of general aviation aircraft by crash injury investigations.
Kirkham, W R
1982-04-01
An aircraft accident investigation program correlates injuries to occupants with the severity of impacts and structural changes in the crash. Findings brought to the attention of aircraft manufacturers have led to specific aircraft being made more crash-worthy. The finding of a failure in a shoulder harness attachment led to the strengthening of the attachment brace. The way a shoulder harness was joined to a lapbelt was modified following a noted failure. The finding of fractures of lapbelt and shoulder harness cable tiedowns led to the use of stronger cables and modification of the installation. Other findings resulted in a shoulder strap guide being placed on an inertia reel and a side-mounted seat being modified. Described also are three seat-related features which, although meeting FAA standards, during the dynamics of a crash may lack desirable energy attenuation. These findings illustrate the value of aircraft crash injury correlations.
Life-threatening motor vehicle crashes in bright sunlight
Redelmeier, Donald A.; Raza, Sheharyar
2017-01-01
Abstract Bright sunlight may create visual illusions that lead to driver error, including fallible distance judgment from aerial perspective. We tested whether the risk of a life-threatening motor vehicle crash was increased when driving in bright sunlight. This longitudinal, case-only, paired-comparison analysis evaluated patients hospitalized because of a motor vehicle crash between January 1, 1995 and December 31, 2014. The relative risk of a crash associated with bright sunlight was estimated by evaluating the prevailing weather at the time and place of the crash compared with the weather at the same hour and location on control days a week earlier and a week later. The majority of patients (n = 6962) were injured during daylight hours and bright sunlight was the most common weather condition at the time and place of the crash. The risk of a life-threatening crash was 16% higher during bright sunlight than normal weather (95% confidence interval: 9–24, P < 0.001). The increased risk was accentuated in the early afternoon, disappeared at night, extended to patients with different characteristics, involved crashes with diverse features, not apparent with cloudy weather, and contributed to about 5000 additional patient-days in hospital. The increased risk extended to patients with high crash severity as indicated by ambulance involvement, surgical procedures, length of hospital stay, intensive care unit admission, and patient mortality. The increased risk was not easily attributed to differences in alcohol consumption, driving distances, or anomalies of adverse weather. Bright sunlight is associated with an increased risk of a life-threatening motor vehicle crash. An awareness of this risk might inform driver education, trauma staffing, and safety warnings to prevent a life-threatening motor vehicle crash. Level of evidence: Epidemiologic Study, level III. PMID:28072708
Life-threatening motor vehicle crashes in bright sunlight.
Redelmeier, Donald A; Raza, Sheharyar
2017-01-01
Bright sunlight may create visual illusions that lead to driver error, including fallible distance judgment from aerial perspective. We tested whether the risk of a life-threatening motor vehicle crash was increased when driving in bright sunlight.This longitudinal, case-only, paired-comparison analysis evaluated patients hospitalized because of a motor vehicle crash between January 1, 1995 and December 31, 2014. The relative risk of a crash associated with bright sunlight was estimated by evaluating the prevailing weather at the time and place of the crash compared with the weather at the same hour and location on control days a week earlier and a week later.The majority of patients (n = 6962) were injured during daylight hours and bright sunlight was the most common weather condition at the time and place of the crash. The risk of a life-threatening crash was 16% higher during bright sunlight than normal weather (95% confidence interval: 9-24, P < 0.001). The increased risk was accentuated in the early afternoon, disappeared at night, extended to patients with different characteristics, involved crashes with diverse features, not apparent with cloudy weather, and contributed to about 5000 additional patient-days in hospital. The increased risk extended to patients with high crash severity as indicated by ambulance involvement, surgical procedures, length of hospital stay, intensive care unit admission, and patient mortality. The increased risk was not easily attributed to differences in alcohol consumption, driving distances, or anomalies of adverse weather.Bright sunlight is associated with an increased risk of a life-threatening motor vehicle crash. An awareness of this risk might inform driver education, trauma staffing, and safety warnings to prevent a life-threatening motor vehicle crash. Epidemiologic Study, level III.
Risk factors associated with the severity of injury outcome for paediatric road trauma.
Mitchell, R J; Bambach, M R; Foster, K; Curtis, K
2015-05-01
Road trauma is one of the most common causes of injury for children. Yet risk factors associated with different levels of injury severity for childhood road trauma have not been examined in-depth. This study identifies crash and injury risk factors associated with the severity of non-fatal injury outcome for paediatric road trauma. A retrospective analysis was conducted of paediatric road trauma identified in linked police-reported and hospitalisation records during 1 January 2001 to 31 December 2011 in New South Wales (NSW), Australia. The linkage rate was 54%. Injury severity was calculated from diagnosis classifications in hospital records using the International Classification of Disease Injury Severity Score. Univariate and multi-variable logistic regression was conducted. There were 2412 car occupants, 1701 pedestrians and 612 pedal cyclists hospitalised where their hospital record linked to a police report. For car occupants, unauthorised vehicle drivers had twice the odds (OR: 2.21, 95%CI 1.47-3.34) and learner/provisional drivers had one and a half times higher odds (OR: 1.54, 95%CI 1.15-2.07) of a child car occupant sustaining a serious injury compared to a minor injury. For pedal cyclists and pedestrians, there were lower odds of a crash occurring during school commuting time and higher odds of a crash occurring during the weekend or on a dry road for children who sustained a serious versus a minor injury. Injury prevention initiatives, such as restraint and helmet use, that should reduce injury and/or crash severity are advocated. Copyright © 2015 Elsevier Ltd. All rights reserved.
Schiff, Melissa A; Cummings, Peter
2004-11-01
To evaluate agreement between police and trained investigators regarding seat belt use by crash victims, according to injury severity. We used data from the National Accident Sampling System Crashworthiness Data System (CDS) for front seat occupants, 16 years and older, in crashes during 1993-2000. Crashworthiness Data System investigators determined belt use from vehicle inspection, interviews, and medical record information; their assessment was considered the gold standard for this analysis. Occupant severity of injury was categorized in five levels from no injuries to death. We estimated the sensitivity, specificity, and area under receiver operating characteristic curves for police reports of belt use. Among 48,858 occupants, sensitivity of a police report that a belt was used was 95.8% overall and varied only modestly by injury severity. Specificity of a police report that a belt was not used was 69.1% overall; it was the lowest among the uninjured (53.2%) and greatest among the dead (90.4%). The area under the curve was 0.82 (95% confidence interval 0.82-0.83) overall; this was lowest among those not injured (0.75, 95% confidence interval 0.74-0.76) and increased with injury severity to 0.91 (95% confidence interval 0.90-0.93) among those who died. Police usually classify belted crash victims as belted, regardless of injury severity. But they often classify unbelted survivors as belted when they were not. This misclassification may result in exaggerated estimates of seat belt effectiveness in some studies.
Islam, Samantha; Brown, Joshua
2017-11-01
The research described in this paper explored the factors contributing to the injury severity resulting from the motorcycle at-fault accidents in rural and urban areas in Alabama. Given the occurrence of a motorcycle at-fault crash, random parameter logit models of injury severity (with possible outcomes of fatal, major, minor, and possible or no injury) were estimated. The estimated models identified a variety of statistically significant factors influencing the injury severities resulting from motorcycle at-fault crashes. According to these models, some variables were found to be significant only in one model (rural or urban) but not in the other one. For example, variables such as clear weather, young motorcyclists, and roadway without light were found significant only in the rural model. On the other hand, variables such as older female motorcyclists, horizontal curve and at intersection were found significant only in the urban model. In addition, some variables (such as, motorcyclists under influence of alcohol, non-usage of helmet, high speed roadways, etc.) were found significant in both models. Also, estimation findings showed that two parameters (clear weather and roadway without light) in the rural model and one parameter (on weekend) in the urban model could be modeled as random parameters indicating their varying influences on the injury severity due to unobserved effects. Based on the results obtained, this paper discusses the effects of different variables on injury severities resulting from rural and urban motorcycle at-fault crashes and their possible explanations. Copyright © 2017 Elsevier Ltd. All rights reserved.
Effectiveness of graduated driver licensing in reducing motor vehicle crashes.
Foss, R D; Evenson, K R
1999-01-01
To determine whether graduated driver licensing (GDL) systems and nighttime curfews reduce motor vehicle crashes, fatalities, or injuries among young drivers. We used Cochrane Collaboration search strategies to locate studies of graduated licensing or night driving restrictions. Studies were selected if they examined the effects of either (1) a comprehensive graduated driver licensing system including well-integrated components, or (2) nighttime driving restrictions/curfews that could affect young persons' nighttime driving, on a clearly defined crash or injury outcome. Seven studies met inclusion criteria. Two independent studies of the New Zealand graduated licensing program found a sustained 7%-8% reduction in teen driver crash injuries attributable to the program. No other full graduated licensing system has been evaluated to date. Four studies of either a general curfew or a nighttime driving restriction for teens, a key element of graduated licensing, found substantial crash reductions during restricted hours, with 23%-25% lower crash injury and fatality rates for curfews beginning prior to midnight. One study found no change in late night crashes before and after a 1 a.m.-6 a.m. night driving restriction took effect. The logic and empirical bases for graduated licensing are sound. Moreover, there is evidence that one central element, a restriction on nighttime driving by novices, reduces young driver crashes. However, a definitive conclusion about the effectiveness of GDL systems for reducing motor vehicle crashes or crash-related injuries must await examination of other GDL systems. This should be possible within the next few years, as several states and Canadian provinces have recently enacted GDL programs.
An In-depth Study of Abdominal Injuries Sustained by Car Occupants in Frontal Crashes
Frampton, Richard; Lenard, James; Compigne, Sabine
2012-01-01
Currently, neither abdominal injury risk nor rear seat passenger safety is assessed in European frontal crash testing. The objective of this study was to provide real world in-depth analysis of the factors related to abdominal injury for belted front and rear seat occupants in frontal crashes. Rear occupants were significantly more at risk of AIS 2+ and 3+ abdominal injury, followed by front seat passengers and then drivers. This was still the case even after controlling for occupant age. Increasing age was separately identified as a factor related to increased abdominal injury risk in all seating positions. One exception to this trend concerned rear seated 15 to 19 year olds who sustained moderate to serious abdominal injury at almost the same rate as rear occupants aged 65+.No strong association was seen between AIS 2+ abdominal injury rates and gender. The majority of occupant body mass indices ranged from underweight to obese. Across that range, the AIS 2+ abdominal injury rates were very similar but a small number of very obese and extremely obese occupants outside of the range did exhibit noticeably higher rates. An analysis of variance in the rate of AIS 2+ abdominal injury with different restraint systems showed that simple belt systems, as used by most rear seat passengers, were the least protective. Increasing sophistication of the restraint system was related to lower rates of injury. The ANOVA also confirmed occupant age and crash severity as highly associated with abdominal injury risk. The most frequently injured abdominal organs for front seat occupants were the liver and spleen. Abdominal injury patterns for rear seat passengers were very different. While they also sustained significant injuries to solid organs, their rates of injury to the hollow organs (jejunum-ileum, mesentary, colon) were far higher even though the rate of fracture of two or more ribs did not differ significantly between seat positions. These results have implications for the design of restraint systems, particularly in relation to the occurrence of abdominal injury. They also raise issues of crash protection for older occupants as well as the protection afforded in different seating positions. PMID:23169124
A new method for predicting crashworthiness.
Council, F M; Stewart, J R; Cox, C L
1997-01-01
Consumer information concerning the predicted 'safeness' of a new car model is based on the results of crash tests. Unfortunately, because it allows comparisons only within size/weight groups, the information is somewhat incompatible with the normal car-purchase decision process since consumers often consider cars within different groups. In addition, based on past research, the association of the crash-test information with real-world crash outcomes is, at best, somewhat limited. The goal of this study was to explore a methodology for improving this information, a methodology which incorporates not only the crash-test information, but also information concerning real-world occupant injury experience in prior crashes involving similar vehicles ('clones'). The clone information included both driver injury severity in past clone crashes from the North Carolina accident file and various indicators of relative driver injury in clones extracted from published insurance-related data from the Highway Loss Data Institute (HLDI). Final models developed included both measures of the Head Index Criteria (HIC) from the crash test and some measure of clone performances as significant predictors. While the North Carolina clone data is intuitively 'cleaner' in that it describes injury level per crash rather than per insured year, the medical claims indices from the HLDI data consistently were shown to be the stronger predictors. Future research will need to look at ways of better combining the crash-test variables and of possible modifications to the HLDI indices. In general, the analyses generated encouraging results that appear to point to possible improvements in the crashworthiness information.
Safety effects of exclusive and concurrent signal phasing for pedestrian crossing.
Zhang, Yaohua; Mamun, Sha A; Ivan, John N; Ravishanker, Nalini; Haque, Khademul
2015-10-01
This paper describes the estimation of pedestrian crash count and vehicle interaction severity prediction models for a sample of signalized intersections in Connecticut with either concurrent or exclusive pedestrian phasing. With concurrent phasing, pedestrians cross at the same time as motor vehicle traffic in the same direction receives a green phase, while with exclusive phasing, pedestrians cross during their own phase when all motor vehicle traffic on all approaches is stopped. Pedestrians crossing at each intersection were observed and classified according to the severity of interactions with motor vehicles. Observation intersections were selected to represent both types of signal phasing while controlling for other physical characteristics. In the nonlinear mixed models for interaction severity, pedestrians crossing on the walk signal at an exclusive signal experienced lower interaction severity compared to those crossing on the green light with concurrent phasing; however, pedestrians crossing on a green light where an exclusive phase was available experienced higher interaction severity. Intersections with concurrent phasing have fewer total pedestrian crashes than those with exclusive phasing but more crashes at higher severity levels. It is recommended that exclusive pedestrian phasing only be used at locations where pedestrians are more likely to comply. Copyright © 2015. Published by Elsevier Ltd.
NASA Technical Reports Server (NTRS)
Annett, Martin S.; Horta, Lucas G.; Jackson, Karen E.; Polanco, Michael A.; Littell, Justin D.
2012-01-01
Two full-scale crash tests of an MD-500 helicopter were conducted in 2009 and 2010 at NASA Langley's Landing and Impact Research Facility in support of NASA s Subsonic Rotary Wing Crashworthiness Project. The first crash test was conducted to evaluate the performance of an externally mounted composite deployable energy absorber (DEA) under combined impact conditions. In the second crash test, the energy absorber was removed to establish baseline loads that are regarded as severe but survivable. The presence of this energy absorbing device reduced the peak impact acceleration levels by a factor of three. Accelerations and kinematic data collected from the crash tests were compared to a system-integrated finite element model of the test article developed in parallel with the test program. In preparation for the full-scale crash test, a series of sub-scale and MD-500 mass simulator tests were conducted to evaluate the impact performances of various components and subsystems, including new crush tubes and the DEA blocks. Parameters defined for the system-integrated finite element model were determined from these tests. Results from 19 accelerometers placed throughout the airframe were compared to finite element model responses. The model developed for the purposes of predicting acceleration responses from the first crash test was inadequate when evaluating more severe conditions seen in the second crash test. A newly developed model calibration approach that includes uncertainty estimation, parameter sensitivity, impact shape orthogonality, and numerical optimization was used to calibrate model results for the full-scale crash test without the DEA. This combination of heuristic and quantitative methods identified modeling deficiencies, evaluated parameter importance, and proposed required model changes. The multidimensional calibration techniques presented here are particularly effective in identifying model adequacy. Acceleration results for the calibrated model were compared to test results and the original model results. There was a noticeable improvement in the pilot and copilot region, a slight improvement in the occupant model response, and an over-stiffening effect in the passenger region. One lesson learned was that this approach should be adopted early on, in combination with the building-block approaches that are customarily used, for model development and pretest predictions. Complete crash simulations with validated finite element models can be used to satisfy crash certification requirements, potentially reducing overall development costs.
Development of a time sensitivity score for frequently occurring motor vehicle crash injuries.
Schoell, Samantha L; Doud, Andrea N; Weaver, Ashley A; Talton, Jennifer W; Barnard, Ryan T; Martin, R Shayn; Meredith, J Wayne; Stitzel, Joel D
2015-03-01
Injury severity alone is a poor indicator of the time sensitivity of injuries. The purpose of the study was to quantify the urgency with which the most frequent motor vehicle crash injuries require treatment, according to expert physicians. The time sensitivity was quantified for the top 95% most frequently occurring Abbreviated Injury Scale (AIS) 2+ injuries in the National Automotive Sampling System-Crashworthiness Data System (NASS-CDS) 2000-2011. A Time Sensitivity Score was developed using expert physician survey data in which physicians were asked to determine whether a particular injury should go to a Level I/II trauma center and the urgency with which that injury required treatment. When stratifying by AIS severity, the mean Time Sensitivity Score increased with increasing AIS severity. The mean Time Sensitivity Scores by AIS severity were as follows: 0.50 (AIS 2); 0.78 (AIS 3); 0.92 (AIS 4); 0.97 (AIS 5); and 0.97 (AIS 6). When stratifying by anatomical region, the head, thorax, and abdomen were the most time sensitive. Appropriate triage depends on multiple factors, including the severity of an injury, the urgency with which it requires treatment, and the propensity of a significant injury to be missed. The Time Sensitivity Score did not correlate highly with the widely used AIS severity scores, which highlights the inability of AIS scores to capture all aspects of injury severity. The Time Sensitivity Score can be useful in Advanced Automatic Crash Notification systems for identifying highly time sensitive injuries in motor vehicle crashes requiring prompt treatment at a trauma center. Copyright © 2015 American College of Surgeons. Published by Elsevier Inc. All rights reserved.
A test-based method for the assessment of pre-crash warning and braking systems.
Bálint, András; Fagerlind, Helen; Kullgren, Anders
2013-10-01
In this paper, a test-based assessment method for pre-crash warning and braking systems is presented where the effectiveness of a system is measured by its ability to reduce the number of injuries of a given type or severity in car-to-car rear-end collisions. Injuries with whiplash symptoms lasting longer than 1 month and MAIS2+ injuries in both vehicles involved in the crash are considered in the assessment. The injury reduction resulting from the impact speed reduction due to a pre-crash system is estimated using a method which has its roots in the dose-response model. Human-machine interaction is also taken into account in the assessment. The results reflect the self-protection as well as the partner-protection performance of a pre-crash system in the striking vehicle in rear-end collisions and enable a comparison between two or more systems. It is also shown how the method may be used to assess the importance of warning as part of a pre-crash system. Copyright © 2013 Elsevier Ltd. All rights reserved.
Seacrist, Thomas; Douglas, Ethan C; Huang, Elaine; Megariotis, James; Prabahar, Abhiti; Kashem, Abyaad; Elzarka, Ayya; Haber, Leora; MacKinney, Taryn; Loeb, Helen
2018-02-28
Motor vehicle crashes are the leading cause of death among young drivers. Though previous research has focused on crash events, near crashes offer additional data to help identify driver errors that could potentially lead to crashes as well as evasive maneuvers used to avoid them. The Strategic Highway Research Program 2 (SHRP2) Naturalistic Driving Study (NDS) contains extensive data on real-world driving and offers a reliable methodology to quantify and study near crashes. This article presents findings on near crashes and how they compare to crash events among teen, young adult, and experienced adult drivers. A subset from the SHRP2 database consisting of 1,653 near crashes for teen (16-19 years, n = 550), young adult (20-24 years, n = 748), and experienced adult (35-54 years, n = 591) drivers was used. Onboard instrumentation including scene cameras, accelerometers, and Global Positioning System logged time series data at 10 Hz. Scene videos were reviewed for all events to classify near crashes based on 7 types: rear-end, road departure, intersection, head-on, side-swipe, pedestrian/cyclist, and animal. Near crash rates, incident type, secondary tasks, and evasive maneuvers were compared across age groups and between crashes and near crashes. For rear-end near crashes, vehicle dynamic variables including near crash severity, headway distance, time headway, and time to collision at the time of braking were compared across age groups. Crashes and near crashes were combined to compare the frequency of critical events across age. Teen drivers exhibited a significantly higher (P <.01) near crash rate than young adult and experienced adult drivers. The near crash rates were 81.6, 56.6, and 37.3 near crashes per million miles for teens, young adults, and experienced adults, respectively. Teens were also involved in significantly more rear-end (P <.01), road departure (P <.01), side-swipe (P <.01), and animal (P <.05) near crashes compared to young and experienced adults. Teens exhibited a significantly greater (P <.01) critical event rate of 102.2 critical events per million miles compared to 72.4 and 40.0 critical events per million miles for young adults and experienced adults, respectively; the critical event rate ratio was 2.6 and 1.8 for teens and young adults, respectively. To our knowledge, this is the first study to examine near crashes among teen, young adult, and experienced adult drivers using SHRP2 naturalistic data. Near crash and critical event rates significantly decreased with increasing age and driver experience. Overall, teens were more than twice as likely to be involved in critical events compared to experienced adults. These data can be used to develop more targeted driver training programs and help manufacturers design active safety systems based on the most common driving errors for vulnerable road users.
The role of conspicuity in preventing bicycle crashes involving a motor vehicle.
Tin Tin, Sandar; Woodward, Alistair; Ameratunga, Shanthi
2015-06-01
Bicycle use, despite its proven health and other benefits, is rarely part of everyday travel for many people due to the perceived risk of injury from collision crashes. This article investigated the role of physical vs. attention conspicuity in preventing bicycle crashes involving a motor vehicle in New Zealand. The Taupo Bicycle Study involved 2590 adult cyclists recruited in 2006 (43.1% response rate) and followed for bicycle crash outcomes through linkage to four national databases. A composite measure of physical conspicuity was created using latent class analysis based on the use of fluorescent colours, lights and reflective materials, and the main colour of top, helmet and bike frame. Attention conspicuity was assessed based on regional differences in travel patterns and the amount of riding in a bunch. Cox regression modelling for repeated events was performed with multivariate adjustments. During a median follow-up period of 6.4 years, 162 participants experienced 187 bicycle-motor vehicle crashes. The crash risk was not predicted by the four latent classes identified and the amount of bunch riding but was higher in Auckland, the region with the lowest level of bicycle use relative to car use. In subgroup analyses, compared to other latent classes, the most physically conspicuous group had a higher risk in Auckland but a lower risk in other regions. Conspicuity aids may not be effective in preventing bicycle-motor vehicle crashes in New Zealand, particularly in Auckland, where attention conspicuity is low. © The Author 2014. Published by Oxford University Press on behalf of the European Public Health Association.
Pelvic ring fractures: implications of vehicle design, crash type, and occupant characteristics.
Rowe, Stephen A; Sochor, Mark S; Staples, Kurtis S; Wahl, Wendy L; Wang, Stewart C
2004-10-01
Pelvic ring fractures (PRFs) are a major cause of morbidity and mortality in motor vehicle collisions (MVCs). Understanding the factors leading to PRFs may help improve vehicle design and safety. This study sought to determine the vehicular, crash, and occupant characteristics that contribute to PRFs. From 1997 to 2003, 240 adult patients involved in lateral or frontal crashes were prospectively studied. Comprehensive crash reconstructions, vehicle analysis, and occupant data were compiled and analyzed as part of the national Crash Injury Research Engineering Network project. Of 240 study patients, 38 had PRFs. The incidence of PRFs was significantly associated with female gender, lateral impact crashes, vehicle incompatibility, and severity of crash. Seat belts and airbags were not protective against PRFs in either lateral or frontal crashes. All vehicles in the current study were less than 6 years old at the time of the MVC and thus reflect newer safety designs. Compared with studies of PRFs in MVCs before the widespread adoption of modern safety standards, our series suggests there has been a modest decrease in the incidence of PRFs in newer vehicles. Current safety standards do not adequately protect against PRFs, especially in lateral MVCs involving incompatibility and female occupants. New technology needs to be developed and implemented. Our data suggest that side impact airbags, alteration of vehicle geometry, and increased reinforcement of side panels and doors may result in fewer PRFs.
Determining the drivers' acceptance of EFTCD in highway work zones.
Bai, Yong; Li, Yingfeng
2011-05-01
Traffic safety is a major concern in the temporary one-lane, two-way highway work zones due to the increasing of construction and maintenance operations. To prevent rear-end crashes and to mitigate the severity of these crashes caused by the inattentive driving, the utilization of the Emergency Flasher Traffic Control Device (EFTCD) was under consideration by government agencies, in addition to existing temporary traffic control devices installed in the one-lane, two-way highway work zones. The EFTCD was a newly proposed traffic warning device implemented through the use of vehicles' hazard warning flashers. The primary objective of the research project was to investigate the drivers' acceptance of the proposed EFTCD by measuring the mean speed changes of vehicles with and without EFTCD and by evaluating the drivers' opinions of the EFTCD using the survey method. Field experimental results revealed that the EFTCD effectively reduced the mean vehicle speeds in the upstream of two work zones. A slow speed is more likely to reduce the severity of a crash in work zones. In addition, survey results indicated that 60% of the drivers thought the EFTCD signified a need for speed reduction and 82% of drivers recommended the implementation of the EFTCD in one-lane, two-way work zones. These results provide the necessary scientific justifications for the government agencies to decide if the EFTCD should be implemented in the one-lane, two-way highway work zones to prevent rear-end crashes and to mitigate the severity of these crashes. Copyright © 2010 Elsevier Ltd. All rights reserved.
DOT National Transportation Integrated Search
2016-12-31
Some of the existing software and hardware used by law enforcement agencies to collect crash data are obsolete for several reasons, ranging from budget constraints to lack of coordination across various groups. The most significant consequence of usi...
DOT National Transportation Integrated Search
1997-12-01
This annual report presents descriptive statistics about traffic crashes of all severities, from those that result in property damage to those that result in the loss of human life. Information from two of the National Highway Traffic Safety Administ...
DOT National Transportation Integrated Search
2006-01-01
This annual report presents descriptive statistics about traffic crashes of all severities, from those that result in property damage to those that result in the loss of human life. Information from two of the National Highway Traffic Safety Administ...
DOT National Transportation Integrated Search
2007-01-01
This annual report presents descriptive statistics about traffic crashes of all severities, from those that result in property damage to those that result in the loss of human life. Information from two of the National Highway Traffic Safety Administ...
DOT National Transportation Integrated Search
2001-12-01
This annual report presents descriptive statistics about traffic crashes of all severities, from those that result in property damage to those that result in the loss of human life. Information from two of the National Highway Traffic Safety Administ...
DOT National Transportation Integrated Search
2002-12-01
This annual report presents descriptive statistics about traffic crashes of all severities, from those that result in property damage to those that result in the loss of human life. Information from two of the National Highway Traffic Safety Administ...
DOT National Transportation Integrated Search
1999-10-01
This annual report presents descriptive statistics about traffic crashes of all severities, from those that result in property damage to those that result in the loss of human life. Information from two of the National Highway Traffic Safety Administ...
DOT National Transportation Integrated Search
2004-01-01
This annual report presents descriptive statistics about traffic crashes of all severities, from those that result in property damage to those that result in the loss of human life. Information from two of the National Highway Traffic Safety Administ...
DOT National Transportation Integrated Search
2005-01-01
This annual report presents descriptive statistics about traffic crashes of all severities, from those that result in property damage to those that result in the loss of human life. Information from two of the National Highway Traffic Safety Administ...
DOT National Transportation Integrated Search
2000-12-01
This annual report presents descriptive statistics about traffic crashes of all severities, from those that result in property damage to those that result in the loss of human life. Information from two of the National Highway Traffic Safety Administ...
DOT National Transportation Integrated Search
1995-08-01
This annual report presents descriptive statistics about traffic crashes of all severities, from those that result in property damage to those that result in the loss of human life. Information from two of the National Highway Traffic Safety Administ...
Wilson, Suzanne J; Begg, Dorothy J; Samaranayaka, Ari
2012-11-01
Linking hospital discharge and police traffic crash records has been used to provide information on causes and outcomes for hospitalised traffic crash cases. Motorcyclists are particularly vulnerable to injury in a traffic crash, but no published linkage studies have reported in detail on this road user group. The present study examined motorcycle traffic crash injury cases in New Zealand in 2000-2004 by probabilistically linking national hospital discharge records with police traffic crash reports. Injury cases had to have spent at least one night in hospital before being discharged and were defined as serious or moderate based on their International Classification of Disease Injury Severity Scores (ICISS). Despite a robust linkage process, only 46% of cases could be linked to a police record; 60% of the serious injuries and 41% of the moderate. The low linkage was most likely due to under-reporting of crashes to or by the police. While moderate injury cases were expected to be under-reported, the level of under-reporting of cases with serious threat-to-life injuries is concerning. To assess whether the linked dataset could provide valid information on the crash circumstances and injury outcomes of hospitalised motorcycle crash cases, the characteristics of the linked and unlinked hospital discharge cases were compared using chi-square tests and multivariate logistic regression. Serious injury cases were less likely to be linked if only one vehicle was involved, or the injured riders and passengers were younger than 20 years or spent less than one week in hospital. For moderate injury cases, there were also differences in linkage by injured body region and crash month. While these discrepancies need to taken into consideration when interpreting results, the linked hospital-police dataset has the potential to provide insights into motorcycle crash circumstances and outcomes not otherwise obtainable. Copyright © 2011 Elsevier Ltd. All rights reserved.
Viano, David C; Parenteau, Chantal S
2016-04-01
This study investigated the change in the fatality and severe injury risks in rear impacts with vehicle model years (MY) grouped prior to, during the phase-in and after the revision to FMVSS 301. FARS and NASS-CDS data were used to determine the injury risks of non-ejected occupants in light vehicles involving non-rollover, rear impacts. The data were analyzed by MY groups: 1996-2001, 2002-2007 and 2008+ to represent the years prior to, during the phase-in and post-revision phase-in of FMVSS 301. The 1996-2013 FARS data were analyzed for rear crashes defined by the initial crash direction (IMPACT1) and direction with most damage (IMPACT2) to the rear. Fatality risk was determined by the number of fatally injured occupants per all occupants with known injury status. The 1994-2013 NASS-CDS was analyzed for rear crashes defined by the damage area variable. The risk of severe injury (MAIS 4+F) was determined as the number of occupants with MAIS 4+F injury per all occupants with known injury status. The distribution of rear crashes was determined by impact location and crash severity. NASS-CDS electronic cases with 2008+ MY vehicles were analyzed to evaluate the vehicle and occupant performance. The fatality risk was 20.6% in the 1996-2001, 17.3% in the 2002-2007 and 15.0% in the 2008+ MY vehicles using FARS with the initial crash direction variable (IMPACT1) to the rear. There was a 27.1% reduction in risk with post-FMVSS 301 vehicles 2008+ MY. The risk was 19.0%, 15.4% and 12.8% with the most damage variable (IMPACT2) to the rear. There was 32.8% reduction in risk with 2008+ MY vehicles. The NASS-CDS analysis showed that the risk of severe injury (MAIS 4+F) was 0.27±0.05% for 1996-2001, 0.30±0.13% for 2002-2007 and 0.08±0.04% for 2008+ MY year vehicles. There was a 70.2% reduction in the risk for severe injury with 2008+ MY vehicles. The NASS-CDS case review of MAIS 4+F injury in rear impacts of 2008+ MY vehicles that comply with the revised FMVSS 301 indicated that the crashes were very severe and generally involved significant 2nd row intrusion. The revision to FMVSS 301 has effectively reduced the risks for fatal and severe injury in vehicles compliant with the revision (2008+ MY). The reduction was 27.1-32.8% in fatality risk using FARS data and 70.2% in severe injury risk using the NASS-CDS when compared to vehicles prior to the phase-in of the revised FMVSS 301 (1996-2001 MY vehicles). It is not possible to parse the effects of other design changes in seats and restraint systems that also increased safety over the study years. Copyright © 2015 Elsevier Ltd. All rights reserved.
Survivors’ experiences from a train crash
Saveman, Britt-Inger
2011-01-01
Rarely described are people's lived experiences from severe injury events such as train crashes. The number of train crashes named disasters with ≥10 killed and/or ≥100 nonfatally injured grows globally and the trend shows that more people survive these disasters today than did so in the past. This results in an increased number of survivors needing care. The aim of the study was to explore survivors’ experiences from a train crash. Narrative interviews were performed with 14 passengers 4 years after a train crash event. Qualitative content analysis was used to analyse the interviews. Experiences were captured in three main themes: (1) Living in the mode of existential threat describes how the survivors first lost control, then were thrown into a state of unimaginable chaos as they faced death. (2) Dealing with the unthinkable described how survivors restored control, the central role of others, and the importance of reconstructing the event to move forward in their processing. (3) Having cheated death shows how some became shackled by their history, whereas others overcame the haunting of unforgettable memories. Furthermore, the result shows how all experienced a second chance in life. Experiencing a train crash meant that the passengers experienced severe vulnerability and a threat to life and interdependence turned out to play a crucial role. Focusing on helping other passengers on site was one way to regain the loss of control and kept the chaos at bay. Family, friends, and fellow passengers turned out to be extremely important during the recovery process why such closeness should be promoted and facilitated. PMID:22125573
Xie, Kun; Ozbay, Kaan; Kurkcu, Abdullah; Yang, Hong
2017-08-01
This study aims to explore the potential of using big data in advancing the pedestrian risk analysis including the investigation of contributing factors and the hotspot identification. Massive amounts of data of Manhattan from a variety of sources were collected, integrated, and processed, including taxi trips, subway turnstile counts, traffic volumes, road network, land use, sociodemographic, and social media data. The whole study area was uniformly split into grid cells as the basic geographical units of analysis. The cell-structured framework makes it easy to incorporate rich and diversified data into risk analysis. The cost of each crash, weighted by injury severity, was assigned to the cells based on the relative distance to the crash site using a kernel density function. A tobit model was developed to relate grid-cell-specific contributing factors to crash costs that are left-censored at zero. The potential for safety improvement (PSI) that could be obtained by using the actual crash cost minus the cost of "similar" sites estimated by the tobit model was used as a measure to identify and rank pedestrian crash hotspots. The proposed hotspot identification method takes into account two important factors that are generally ignored, i.e., injury severity and effects of exposure indicators. Big data, on the one hand, enable more precise estimation of the effects of risk factors by providing richer data for modeling, and on the other hand, enable large-scale hotspot identification with higher resolution than conventional methods based on census tracts or traffic analysis zones. © 2017 Society for Risk Analysis.
Long-term medical consequences for child occupants 0 to 12 years injured in car crashes.
Bohman, Katarina; Stigson, Helena; Krafft, Maria
2014-01-01
There is limited knowledge of the long-term medical consequences for children injured in car crashes. Thus, in the event of injury, the aim of the study was to specify patterns and risks of injuries resulting in permanent medical impairment of children (0-12 years) for different body regions and injury severity levels, according to Abbreviated Injury Scale (AIS). The aim was also to compare the impairment outcome with adults. Data were obtained from the Folksam insurance company, including reported car crashes from 1998 to 2010 with at least one injured child 0-12 years of age. In all, 2619 injured children with 3704 reported medical diagnoses were identified. All injuries were classified according to the AIS 2005 revision. If the child had not recovered within 1 year postinjury an assessment of permanent medical impairment (PMI) was made by one or several medical specialists. In all, 55 children sustained 59 injuries resulting in PMI of which 75 percent were at AIS 1 or AIS 2. The head and cervical spine were the body regions sustaining the most injuries resulting in PMI. Sixty-eight percent of all injuries resulting in PMI were AIS 1 injuries to the cervical spine, with the majority occurring in frontal or rear impacts. Given an injury to the cervical spine, the risk of injuries resulting in PMI was 3 percent, and older children (≥6 years) had a significantly higher risk (3% versus 1%) than younger children. The head was the second most commonly injured body region with injuries resulting in PMI (12/59), which were predominantly AIS 2+. In addition, mild traumatic brain injuries at AIS 1 were found to lead to PMI. Whereas for children the injuries leading to PMI were primarily limited to the head and cervical spine, adults sustained injuries that led to PMI from a more diverse distribution of body regions. The pattern of injuries resulting in permanent medical impairment is different for children and adults; therefore, safety priorities for children need to be based on child data. The majority of those injuries leading to PMI were at lower AIS levels. Furthermore, AIS 1 cervical spine and AIS 1+ head injuries should be given priority concerning mitigation of long-term consequences for children.
Evidence of Human Induce Factors in Automotive Crashes in Nigeria
Abidemi, Awopeju K.
2013-01-01
Nigeria is one of the countries in Africa highly affected by automotive crashes which led to establishment of Federal Road Safety Corps (FRSC). The organization fought and is fighting against reckless driving in the country to prevent loss of life through automotive crashes. The record of the organization and the Statistical investigation of the researcher reveal that most of the crashes were due to human error such as alcoholism, inexperience and peer influence on the high-way. The data for the research was collected from published report of FRSC 2012 and analyzed using chi-square dependency test and charts due to the nature of the presentation. Ratios were used to determine Number of people killed per Road Total Crashes (RTC), Casualty per RTC and RTC severity Index from 2007 to 2010 in the country. Among the human induced factors, it was discovered that most of the drivers involved in road crashes were drunk during the period and the years of experience play major role in the automotive crashes as drivers with less than 2years of experience were more involved than the other groups. In the consideration of life style of drivers involve in road crashes, it was discovered that drivers with less than 30years of age are vulnerable to road crashes than drivers with ages higher than 30years. Among the findings, the most common automobile in Nigeria road crashes is commercial buses in the years considered. It was recommended that proper and adequate training should be given to drivers on the high-way to prevent injuries and loss of life. Alcoholism should be discouraged in totality and age of obtaining drivers license could be increased in developing countries such as Nigeria. PMID:24406969
Sunnevång, Cecilia; Pipkorn, Bengt; Boström, Ola
2015-01-01
This study aims, by means of the WorldSID 50th percentile male, to evaluate thoracic loading and injury risk to the near-side occupant due to occupant-to-occupant interaction in combination with loading from an intruding structure. Nine vehicle crash tests were performed with a 50th percentile WorldSID male dummy in the near-side (adjacent to the intruding structure) seat and a THOR or ES2 dummy in the far-side (opposite the intruding structure) seat. The near-side seated WorldSID was equipped with 6 + 6 IR-Traccs (LH and RH) in the thorax/abdomen enabling measurement of bilateral deflection. To differentiate deflection caused by the intrusion, and the deflection caused by the neighboring occupant, time history curves were analyzed. The crash tests were performed with different modern vehicles, equipped with thorax side airbags and inflatable curtains, ranging from a compact car to a large sedan, and in different loading conditions such as car-to-car, barrier, and pole tests. Lateral delta V based on vehicle tunnel acceleration and maximum residual intrusion at occupant position were used as a measurement of crash severity to compare injury measurements. In the 9 vehicle crash tests, thoracic loading, induced by the intruding structure as well as from the far-side occupant, varied due to the size and structural performance of the car as well as the severity of the crash. Peak deflection on the thoracic outboard side occurred during the first 50 ms of the event. Between 70 to 150 ms loading induced by the neighboring occupant occurred and resulted in an inboard-side peak deflection and viscous criterion. In the tests where the target vehicle lateral delta V was below 30 km/h and intrusion less than 200 mm, deflections were low on both the outboard (20-40 mm) and inboard side (10-15 mm). At higher crash severities, delta V 35 km/h and above as well as intrusions larger than 350 mm, the inboard deflections (caused by interaction to the far-side occupant) were of the same magnitude or even higher (30-70 mm) than the outboard deflections (30-50 mm). A WorldSID 50th percentile male equipped with bilateral IR-Traccs can detect loading to the thorax from a neighboring occupant making injury risk assessment feasible for this type of loading. At crash severities resulting in a delta V above 35 km/h and intrusions larger than 350 mm, both the inboard deflection and VC resulted in high risks of Abbreviated Injury Scale (AIS) 3+ injury, especially for a senior occupant.
Crash Frequency Analysis Using Hurdle Models with Random Effects Considering Short-Term Panel Data
Chen, Feng; Ma, Xiaoxiang; Chen, Suren; Yang, Lin
2016-01-01
Random effect panel data hurdle models are established to research the daily crash frequency on a mountainous section of highway I-70 in Colorado. Road Weather Information System (RWIS) real-time traffic and weather and road surface conditions are merged into the models incorporating road characteristics. The random effect hurdle negative binomial (REHNB) model is developed to study the daily crash frequency along with three other competing models. The proposed model considers the serial correlation of observations, the unbalanced panel-data structure, and dominating zeroes. Based on several statistical tests, the REHNB model is identified as the most appropriate one among four candidate models for a typical mountainous highway. The results show that: (1) the presence of over-dispersion in the short-term crash frequency data is due to both excess zeros and unobserved heterogeneity in the crash data; and (2) the REHNB model is suitable for this type of data. Moreover, time-varying variables including weather conditions, road surface conditions and traffic conditions are found to play importation roles in crash frequency. Besides the methodological advancements, the proposed technology bears great potential for engineering applications to develop short-term crash frequency models by utilizing detailed data from field monitoring data such as RWIS, which is becoming more accessible around the world. PMID:27792209
Perception and biodynamics in unalerted precrash response.
McGehee, Daniel V; Carsten, Oliver M J
2010-01-01
This research seeks to better understand unalerted driver response just prior to a serious vehicle crash. Few studies have been able to view a crash from the inside-with a camera focused on the driver and occupants. Four studies are examined: 1) a high-fidelity simulator study with an unalerted intersection incursion crash among 107 drivers; 2) four crashes from the Virginia Tech Transportation Institute (VTTI) 100 car study; 3) 58 crashes from vehicles equipped with an event triggered video recorder; and 4) a custom-designed high-fidelity simulator experiment that examined unalerted driver response to a head-on crash with a heavy truck. Analyses concentrate on decomposing driver perception, action, facial and postural changes with a focus on describing the neurophysiologic mechanisms designed to respond to danger. Results indicate that drivers involved in severe crashes generally have preview that an impact is about to occur. They respond first with vehicle control inputs (accelerator pedal release) along with facial state changes and withdrawal of the head back towards the head restraint. These responses frequently occur almost simultaneously, providing safety system designers with a number of reliable driver performance measures to monitor. Understanding such mechanisms may assist future advanced driver assistance systems (ADAS), advanced restraints, model development of advanced anthropomorphic test dummies (ATDs), injury prediction and the integration of active and passive safety systems.
Three Cases of Spine Fractures after an Airplane Crash.
Lee, Han Joo; Moon, Bong Ju; Pennant, William A; Shin, Dong Ah; Kim, Keung Nyun; Yoon, Do Heum; Ha, Yoon
2015-10-01
While injuries to the spine after an airplane crash are not rare, most crashes result in fatal injuries. As such, few studies exist that reported on spine fractures sustained during airplane accidents. In this report, we demonstrate three cases of spine fractures due to crash landing of a commercial airplane. Three passengers perished from injuries after the crash landing, yet most of the passengers and crew on board survived, with injuries ranging from minor to severe. Through evaluating our three spine fracture patients, it was determined that compression fracture of the spine was the primary injury related to the airplane accident. The first patient was a 20-year-old female who sustained a T6-8 compression fracture without neurologic deterioration. The second patient was a 33-year-old female with an L2 compression fracture, and the last patient was a 49-year-old male patient with a T8 compression fracture. All three patients were managed conservatively and required spinal orthotics. During the crash, each of these patients were subjected to direct, downward high gravity z-axis (Gz) force, which gave rise to load on the spine vertically, thereby causing compression fracture. Therefore, new safety methods should be developed to prevent excessive Gz force during airplane crash landings.
Delgado, M Kit; Wanner, Kathryn J; McDonald, Catherine
2016-06-16
Motor vehicle crashes are the leading cause of death in adolescents, and drivers aged 16-19 are the most likely to die in distracted driving crashes. This paper provides an overview of the literature on adolescent cellphone use while driving, focusing on the crash risk, incidence, risk factors for engagement, and the effectiveness of current mitigation strategies. We conclude by discussing promising future approaches to prevent crashes related to cellphone use in adolescents. Handheld manipulation of the phone while driving has been shown to have a 3 to 4-fold increased risk of a near crash or crash, and eye glance duration greater than 2 seconds increases crash risk exponentially. Nearly half of U.S. high school students admit to texting while driving in the last month, but the frequency of use according to vehicle speed and high-risk situations remains unknown. Several risk factors are associated with cell phone use while driving including: parental cellphone use while driving, social norms for quick responses to text messages, and higher levels of temporal discounting. Given the limited effectiveness of current mitigation strategies such as educational campaigns and legal bans, a multi-pronged behavioral and technological approach addressing the above risk factors will be necessary to reduce this dangerous behavior in adolescents.
Prescription of antiepileptics and the risk of road traffic crash.
Orriols, Ludivine; Foubert-Samier, Alexandra; Gadegbeku, Blandine; Delorme, Bernard; Tricotel, Aurore; Philip, Pierre; Moore, Nicholas; Lagarde, Emmanuel
2013-03-01
Studies assessing the impact of epilepsy and its medication on the risk of road traffic crashes have shown inconsistent results. The aim in this study was to assess this risk using French databases. Data from three French national databases were extracted and matched: the national health care insurance database, police reports, and the national police database of injurious crashes. Only antiepileptics prescribed predominantly in epilepsy were studied (phenobarbital, phenytoin, ethosuximide, valproic acid, vigabatrin, tiagabin, levitiracetam, zonisamide, and lacosamide). A case-control analysis comparing responsible and non-responsible drivers and a case-crossover analysis were performed. Drivers (72 685) involved in an injurious crash in France between July 2005 and May 2008, were included. Drivers exposed to prescribed antiepileptic medicines (n = 251) had an increased risk of being responsible for a crash (OR 1.74 [1.29-2.34]). The association was also significant for the most severe epileptic patients (n = 99; OR = 2.20 [1.31-3.69]). Case-crossover analysis found no association between crash risk and treatment prescription. Patients with prescription of antiepileptic drugs should be cautioned about their potential risk of road traffic crash. This risk is however more likely to be related to seizures than to the effect of antiepileptic medicines. © The Author(s) 2013.
Three Cases of Spine Fractures after an Airplane Crash
Lee, Han Joo; Moon, Bong Ju; Pennant, William A.; Shin, Dong Ah; Kim, Keung Nyun; Yoon, Do Heum
2015-01-01
While injuries to the spine after an airplane crash are not rare, most crashes result in fatal injuries. As such, few studies exist that reported on spine fractures sustained during airplane accidents. In this report, we demonstrate three cases of spine fractures due to crash landing of a commercial airplane. Three passengers perished from injuries after the crash landing, yet most of the passengers and crew on board survived, with injuries ranging from minor to severe. Through evaluating our three spine fracture patients, it was determined that compression fracture of the spine was the primary injury related to the airplane accident. The first patient was a 20-year-old female who sustained a T6-8 compression fracture without neurologic deterioration. The second patient was a 33-year-old female with an L2 compression fracture, and the last patient was a 49-year-old male patient with a T8 compression fracture. All three patients were managed conservatively and required spinal orthotics. During the crash, each of these patients were subjected to direct, downward high gravity z-axis (Gz) force, which gave rise to load on the spine vertically, thereby causing compression fracture. Therefore, new safety methods should be developed to prevent excessive Gz force during airplane crash landings. PMID:27169094
Delgado, M. Kit; Wanner, Kathryn J.; McDonald, Catherine
2016-01-01
Motor vehicle crashes are the leading cause of death in adolescents, and drivers aged 16–19 are the most likely to die in distracted driving crashes. This paper provides an overview of the literature on adolescent cellphone use while driving, focusing on the crash risk, incidence, risk factors for engagement, and the effectiveness of current mitigation strategies. We conclude by discussing promising future approaches to prevent crashes related to cellphone use in adolescents. Handheld manipulation of the phone while driving has been shown to have a 3 to 4-fold increased risk of a near crash or crash, and eye glance duration greater than 2 seconds increases crash risk exponentially. Nearly half of U.S. high school students admit to texting while driving in the last month, but the frequency of use according to vehicle speed and high-risk situations remains unknown. Several risk factors are associated with cell phone use while driving including: parental cellphone use while driving, social norms for quick responses to text messages, and higher levels of temporal discounting. Given the limited effectiveness of current mitigation strategies such as educational campaigns and legal bans, a multi-pronged behavioral and technological approach addressing the above risk factors will be necessary to reduce this dangerous behavior in adolescents. PMID:27695663
Stipancic, Joshua; Miranda-Moreno, Luis; Saunier, Nicolas
2018-06-01
Network screening is a key element in identifying and prioritizing hazardous sites for engineering treatment. Traditional screening methods have used observed crash frequency or severity ranking criteria and statistical modelling approaches, despite the fact that crash-based methods are reactive. Alternatively, surrogate safety measures (SSMs) have become popular, making use of new data sources including video and, more rarely, GPS data. The purpose of this study is to examine vehicle manoeuvres of braking and accelerating extracted from a large quantity of GPS data collected using the smartphones of regular drivers, and to explore their potential as SSMs through correlation with historical collision frequency and severity across different facility types. GPS travel data was collected in Quebec City, Canada in 2014. The sample for this study contained over 4000 drivers and 21,000 trips. Hard braking (HBEs) and accelerating events (HAEs) were extracted and compared to historical crash data using Spearman's correlation coefficient and pairwise Kolmogorov-Smirnov tests. Both manoeuvres were shown to be positively correlated with crash frequency at the link and intersection levels, though correlations were much stronger when considering intersections. Locations with more braking and accelerating also tend to have more collisions. Concerning severity, higher numbers of vehicle manoeuvres were also related to increased collision severity, though this relationship was not always statistically significant. The inclusion of severity testing, which is an independent dimension of safety, represents a substantial contribution to the existing literature. Future work will focus on developing a network screening model that incorporates these SSMs. Copyright © 2018 Elsevier Ltd. All rights reserved.
Mackay, Murray; Hassan, Ahamedali M.
2000-01-01
Field accident data from NASS/CDS in the US and CCIS in the UK are compared. The UK sample is deliberately weighted to conform to the same AIS proportions (within AIS 2 – 6) as the weighted NASS data so that crash severity distributions can be compared for various selected outcomes. Age and gender have a significant effect on the deltaV distributions and median deltaV values. These differences are documented both for overall AIS 2 - 6, 3 - 6, and 4 - 6, and also for body regions of the head, neck, chest, abdomen and upper and lower extremities. Anomalies between the two samples are profound which raises doubts about the recording of belt use in NASS and the calculation of deltaV at lower crash severities. PMID:11558104
Analyzing the relationship between car generation and severity of motor-vehicle crashes in Denmark.
Rich, Jeppe; Prato, Carlo Giacomo; Hels, Tove; Lyckegaard, Allan; Kristensen, Niels Buus
2013-05-01
While the number of fatalities on Danish roads has decreased in the last 40 years, research has not investigated the contribution of legislation changes, enforcement measures, technological enhancements, infrastructural improvements and human factors to this reduction. In the context of a Danish car market with remarkably high registration tax that causes potential buyers to hold longer onto old cars, the relationship between technological enhancements of vehicles and severity of crashes requires particular attention. The current study investigated the relationship between car generation (i.e., car's first registration year) and injury severity sustained by car drivers involved in accidents in Denmark between 2004 and 2010. A generalized ordered logit model was estimated while controlling for several characteristics of the crash, the vehicle and the persons involved, and a sensitivity analysis was performed to assess the effect of car generation on drivers' injury severity. Results illustrate that newer car generations are associated to significantly lower probability of injury and fatality, and that replacing older cars with newer ones introduces significant and not to be overlooked benefits for both population and society. Copyright © 2013 Elsevier Ltd. All rights reserved.
Anderson, R W G; Searson, D J
2015-02-01
A novel application of age-period-cohort methods are used to explain changes in vehicle based crash rates in New South Wales, Australia over the period 2003-2010. Models are developed using vehicle age, crash period and vehicle cohort to explain changes in the rate of single vehicle driver fatalities and injuries in vehicles less than 13 years of age. Large declines in risk are associated with vehicle cohorts built after about 1996. The decline in risk appears to have accelerated to 12 percent per vehicle cohort year for cohorts since 2004. Within each cohort, the risk of crashing appears to be a minimum at two years of age and increases as the vehicle ages beyond this. Period effects (i.e., other road safety measures) between 2003 and 2010 appear to have contributed to declines of up to about two percent per annum to the driver-fatality single vehicle crash rate, and possibly only negligible improvements to the driver-injury single vehicle crash rate. Vehicle improvements appear to have been responsible for a decline in per-vehicle crash risk of at least three percent per calendar year for both severity levels over the same period. Given the decline in risk associated with more recent vehicle cohorts and the dynamics of fleet turnover, continued declines in per-vehicle crash risk over coming years are almost certain. Copyright © 2014. Published by Elsevier Ltd.
Janstrup, Kira H; Kaplan, Sigal; Hels, Tove; Lauritsen, Jens; Prato, Carlo G
2016-08-17
This study aligns to the body of research dedicated to estimating the underreporting of road crash injuries and adds the perspective of understanding individual and crash factors contributing to the decision to report a crash to the police, the hospital, or both. This study focuses on road crash injuries that occurred in the province of Funen, Denmark, between 2003 and 2007 and were registered in the police, the hospital, or both authorities. Underreporting rates are computed with the capture-recapture method, and the probability for road crash injuries in police records to appear in hospital records (and vice versa) is estimated with joint binary logit models. The capture-recapture analysis shows high underreporting rates of road crash injuries in Denmark and the growth of underreporting not only with the decrease in injury severity but also with the involvement of cyclists (reporting rates of about 14% for serious injuries and 7% for slight injuries) and motorcyclists (reporting rates of about 35% for serious injuries and 10% for slight injuries). Model estimates show that the likelihood of appearing in both data sets is positively related to helmet and seat belt use, number of motor vehicles involved, alcohol involvement, higher speed limit, and females being injured. This study adds significantly to the literature about underreporting by recognizing that understanding the heterogeneity in the reporting rate of road crashes may lead to devising policy measures aimed at increasing the reporting rate by targeting specific road user groups (e.g., males, young road users) or specific situational factors (e.g., slight injuries, arm injuries, leg injuries, weekend).
How to determine an optimal threshold to classify real-time crash-prone traffic conditions?
Yang, Kui; Yu, Rongjie; Wang, Xuesong; Quddus, Mohammed; Xue, Lifang
2018-08-01
One of the proactive approaches in reducing traffic crashes is to identify hazardous traffic conditions that may lead to a traffic crash, known as real-time crash prediction. Threshold selection is one of the essential steps of real-time crash prediction. And it provides the cut-off point for the posterior probability which is used to separate potential crash warnings against normal traffic conditions, after the outcome of the probability of a crash occurring given a specific traffic condition on the basis of crash risk evaluation models. There is however a dearth of research that focuses on how to effectively determine an optimal threshold. And only when discussing the predictive performance of the models, a few studies utilized subjective methods to choose the threshold. The subjective methods cannot automatically identify the optimal thresholds in different traffic and weather conditions in real application. Thus, a theoretical method to select the threshold value is necessary for the sake of avoiding subjective judgments. The purpose of this study is to provide a theoretical method for automatically identifying the optimal threshold. Considering the random effects of variable factors across all roadway segments, the mixed logit model was utilized to develop the crash risk evaluation model and further evaluate the crash risk. Cross-entropy, between-class variance and other theories were employed and investigated to empirically identify the optimal threshold. And K-fold cross-validation was used to validate the performance of proposed threshold selection methods with the help of several evaluation criteria. The results indicate that (i) the mixed logit model can obtain a good performance; (ii) the classification performance of the threshold selected by the minimum cross-entropy method outperforms the other methods according to the criteria. This method can be well-behaved to automatically identify thresholds in crash prediction, by minimizing the cross entropy between the original dataset with continuous probability of a crash occurring and the binarized dataset after using the thresholds to separate potential crash warnings against normal traffic conditions. Copyright © 2018 Elsevier Ltd. All rights reserved.
Overview of the Transport Rotorcraft Airframe Crash Testbed (TRACT) Full Scale Crash Tests
NASA Technical Reports Server (NTRS)
Annett, Martin; Littell, Justin
2015-01-01
The Transport Rotorcraft Airframe Crash Testbed (TRACT) full-scale tests were performed at NASA Langley Research Center's Landing and Impact Research Facility in 2013 and 2014. Two CH-46E airframes were impacted at 33-ft/s forward and 25-ft/s vertical combined velocities onto soft soil, which represents a severe, but potentially survivable impact scenario. TRACT 1 provided a baseline set of responses, while TRACT 2 included retrofits with composite subfloors and other crash system improvements based on TRACT 1. For TRACT 2, a total of 18 unique experiments were conducted to evaluate Anthropomorphic Test Devices (ATD) responses, seat and restraint performance, cargo restraint effectiveness, patient litter behavior, and activation of emergency locator transmitters and crash sensors. Combinations of Hybrid II, Hybrid III, and ES-2 ATDs were placed in forward and side facing seats and occupant results were compared against injury criteria. The structural response of the airframe was assessed based on accelerometers located throughout the airframe and using three-dimensional photogrammetric techniques. Analysis of the photogrammetric data indicated regions of maximum deflection and permanent deformation. The response of TRACT 2 was noticeably different in the horizontal direction due to changes in the cabin configuration and soil surface, with higher acceleration and damage occurring in the cabin. Loads from ATDs in energy absorbing seats and restraints were within injury limits. Severe injury was likely for ATDs in forward facing passenger seats.
On the Fatal Crash Experience of Older Drivers
Kent, Richard; Henary, Basem; Matsuoka, Fumio
2005-01-01
This study describes the fatal crash experiences of older drivers. Data from two U.S. databases (NASS-CDS and FARS) were used. Several crash, vehicle, and occupant characteristics were compared across age groups, including vehicle type, crash direction (PDOF), severity (ΔV), and injured body region. A sub-set of 97 fatally injured drivers was chosen for a detailed case study. The mean travel speed, ΔV, and airbag deployment rate decreased significantly with age (p<0.001 unless noted). Mortality rate increased significantly with age. Older drivers killed were significantly more likely to die of a chest injury (47.3% vs. 24.0% in youngest group) and less likely to die of a head injury (22.0% vs. 47.1% in youngest group). Older drivers were more likely to die at a date after the crash date (“delayed death”), as were males (p=0.003). A 16-year-old driver had a 10.8%–12.0% probability of delayed death, while a 75-year-old had a 20.7%–22.7% probability. For those having a delayed death, the length of the delay increased significantly with age (2.9 days for age 16 vs. 7.9 for age 75). A subjective assessment of the case files indicated that frailty or a pre-existing health condition played a role in 4.3% of the younger drivers’ deaths, but 50.0% of the older group. PMID:16179160
Rogers, Paul; Qualter, Pamela; Wood, Dave
2016-11-01
Two studies examine the impact event vividness, event severity, and prior paranormal belief has on causal attributions for a depicted remarkable coincidence experience. In Study 1, respondents (n = 179) read a hypothetical vignette in which a fictional character accurately predicts a plane crash 1 day before it occurs. The crash was described in either vivid or pallid terms with the final outcome being either severe (fatal) or non-severe (non-fatal). Respondents completed 29 causal attribution items, one attribution confidence item, nine scenario perception items, a popular paranormal belief scale, and a standard demographics questionnaire. Principal axis factoring reduced the 29 attribution items to four attribution factors which were then subjected to a 2 (event vividness) × 2 (event severity) × 2 (paranormal belief) MANCOVA controlling for respondent gender. As expected, paranormal believers attributed the accurate crash prediction less to coincidence and more to both paranormal and transcendental knowing than did paranormal sceptics. Furthermore, paranormal (psychokinesis) believers deemed the prediction more reflective of paranormal knowing to both (1) a vivid/non-fatal and (2) a pallid/fatal crash depiction. Vividness, severity, and paranormal belief types had no impact on attribution confidence. In Study 2, respondents (also n = 179) generated data that were a moderately good fit to the previous factor structure and replicated several differences across attributional pairings albeit for paranormal non-believers only. Corresponding effects for event severity and paranormal belief were not replicated. Findings are discussed in terms of their support for the paranormal misattribution hypothesis and the impact of availability biases in the form of both vividness and severity effects. Methodological issues and future research ideas are also discussed. © 2016 The British Psychological Society.
The effects of drug and alcohol consumption on driver injury severities in single-vehicle crashes.
Behnood, Ali; Mannering, Fred L
2017-07-04
It is well known that alcohol and drugs influence driving behavior by affecting the central nervous system, awareness, vision, and perception/reaction times, but the resulting effect on driver injuries in car crashes is not fully understood. The purpose of this study was to identify factors affecting the injury severities of unimpaired, alcohol-impaired, and drug-impaired drivers. The current article applies a random parameters logit model to study the differences in injury severities among unimpaired, alcohol-impaired, and drug-impaired drivers. Using data from single-vehicle crashes in Cook County, Illinois, over a 9-year period from January 1, 2004, to December 31, 2012, separate models for unimpaired, alcohol-impaired, and drug-impaired drivers were estimated. A wide range of variables potentially affecting driver injury severity was considered, including roadway and environmental conditions, driver attributes, time and location of the crash, and crash-specific factors. The estimation results show significant differences in the determinants of driver injury severities across groups of unimpaired, alcohol-impaired, and drug-impaired drivers. The findings also show that unimpaired drivers are understandably more responsive to variations in lighting, adverse weather, and road conditions, but these drivers also tend to have much more heterogeneity in their behavioral responses to these conditions, relative to impaired drivers. In addition, age and gender were found to be important determinants of injury severity, but the effects varied significantly across all drivers, particularly among alcohol-impaired drivers. The model estimation results show that statistically significant differences exist in driver injury severities among the unimpaired, alcohol-impaired, and drug-impaired driver groups considered. Specifically, we find that unimpaired drivers tend to have more heterogeneity in their injury outcomes in the presence potentially adverse weather and road surface conditions. This makes sense because one would expect unimpaired drivers to apply their full knowledge/judgment range to deal with these conditions, and the variability of this range across the driver population (with different driving experiences, etc.) should be great. In contrast, we find, for the most part, that alcohol-impaired and drug-impaired drivers have far less heterogeneity in the factors that affect injury severity, suggesting an equalizing effect resulting from the decision-impairing substance.