Crash risk by driver age,gender, and time of day using a new exposure methodology

Introduction: Concerns have been raised that the nonlinear relation between crashes and travel exposure invalidates the conventional use of crash rates to control for exposure. A new metric of exposure that bears a linear association to crashes was used as basis for calculating unbiased crash risks. This study compared the two methods – conventional crash rates and new adjusted crash risk – for assessing the effect of driver age, gender, and time of day on the risk of crash involvement and crash fatality. Method: We used police reports of single-car and multi-car crashes with fatal and nonfatal driver injuries that occurred during 2002–2012 in Great Britain. Results: Conventional crash rates were highest in the youngest age group and declined steeply until age 60–69 years. The adjusted crash risk instead peaked at age 21–29 years and reduced gradually with age. The risk of nighttime driving, especially among teenage drivers, was much smaller when based on adjusted crash risks. Finally, the adjusted fatality risk incurred by elderly drivers remained constant across time of day, suggesting that their risk of sustaining a fatal injury due to a crash is more attributable to excess fragility than to crash seriousness. Conclusions: Our findings demonstrate a biasing effect of low travel exposure on conventional crash rates. This implies that conventional methods do not yield meaningful comparisons of crash risk between driver groups and driving conditions of varying exposure to risk. The excess crash rates typically associated with teenage and elderly drivers as well as nighttime driving are attributed in part to overestimation of risk at low travel exposure. Practical Applications: Greater attention should be directed toward crash involvement among drivers in their 20s and 30s as well as younger drivers. Countermeasures should focus on the role of physical vulnerability in fatality risk of elderly drivers.     

Data mining approach to model bus crash severity in Australia

Introduction: Buses are different vehicles in terms of dimensions, maneuverability, and driver's vision. Although bus traveling is a safe mode to travel, the number of annual bus crashes cannot be neglected. Moreover, limited studies have been conducted on the bus involved in fatal crashes. Therefore, identification of the contributing factors in the bus involved fatal crashes can reduce the risk of fatality. Method: Data set of bus involved crashes in the State of Victoria, Australia was analyzed over the period of 2006–2019. Clustering of crash data was accomplished by dividing them into homogeneous categories, and by implementing association rules discovery on the clusters, the factors affecting fatality in bus involved crashes were extracted. Results: Clustering results show bus crashes with all vehicles except motor vehicles and weekend crashes have a high rate of fatality. According to the association rule discovery findings, the factors that increase the risk of bus crashes with non-motor vehicles are: old bus driver, collision with pedestrians at signalized intersections, and the presence of vulnerable road users. Likewise, factors that increase the risk of fatality in bus involved crashes on weekends are: darkness of roads in high-speed zones, pedestrian presence at highways, bus crashes with passenger car by a female bus driver, and the occurrence of multi-vehicle crashes in high-speed zones. Practical Applications: The study provides a sequential pattern of factors, named rules that lead to fatality in bus involved crashes. By eliminating or improving one or all of the factors involved in rules, fatal bus crashes may be prevented. The recommendations to reduce fatality in bus crashes are: observing safe distances with the buses, using road safety campaigns to reduce pedestrians’ distracted behavior, improving the lighting conditions, implementing speed bumps and rumble strips in high-speed zones, installing pedestrian detection systems on buses and setting special bus lanes in crowded areas.     

The fatality consequences of the 65 mph speed limits, 1989

This study examined whether the number of fatalities on rural interstates in 1989 was higher than would be expected based on experience during 1982–1986 and experience on all other roads. Among the 40 states that increased the speed limit to 65 mph on rural interstates, the number of fatalities was 29% higher than expected. Among the eight states retaining a 55 mph maximum speed limit on rural interstates, the observed number of fatalities was 12% lower than expected, although this reduction was not statistically significant. After adjusting the fatality risk on rural interstates for differences in vehicle miles traveled on those roads and for higher passenger vehicle occupancy rates attributable to possible increases in vacation travel, the increased fatality risk was 19%. These data suggest that the majority of the estimated increase in fatalities on rural interstates in 1989 (almost 400 of the approximately 600 extra deaths) can be attributed to the higher speeds resulting from the higher speed limits. Changes in mileage account for the remaining 200 extra deaths.     

Railroad injury: Causes, costs, and comparisons with other transport modes

Safety regulators in the railroad industry need comprehensive injury costs by cause, and cost comparisons to other modes of transport to gain policy insights. This study links case-level data from the Federal Railroad Administration to monetary costs and consequences of specific injuries. Lost quality of life was estimated from physicians' ratings of injury impairment and the value of fatal risk reduction. Railroad injuries and illnesses cause an average of $3 billion in fatality costs and $650 million in nonfatal incident costs annually. Impacts at rail-highway crossings impose three times as much cost as the next highest cause. Commercial air travel is the safest per passenger mile. Trains, second lowest, have injury costs six times higher, but only one-fifth as high as cars. The relative safety of trains and airplanes in transport means highway modes enjoy implicit price subsidies. Better injury cost recovery through taxation or insurance would make the subsidies explicit. More informed modal choices and thus enhanced economic efficiency would result.     

Relationship of traffic fatality rates to maximum state speed limits

Objectives: The objective of this study was to examine the safety effects of increases in U.S. state maximum speed limits during the period 1993–2013.

Methods: Poisson regression was used to model state-by-state annual traffic fatality rates per mile of travel as a function of time, the unemployment rate, the percentage of the driving age population that was younger than 25, per capita alcohol consumption, and the maximum posted speed limit on any road in the state. Separate analyses were conducted for all roads, interstates and freeways, and all other roads.

Results: A 5 mph increase in the maximum state speed limit was associated with an 8% increase in fatality rates on interstates and freeways and a 4% increase on other roads. In total, there were an estimated 33,000 more traffic fatalities during the years 1995–2013 than would have been expected if maximum speed limits had not increased. In 2013 alone, there were approximately 1,900 additional deaths—500 on interstates/freeways and 1,400 on other roads.

Conclusions: There is a definite trend of increased fatality risk when speed limits are raised. As roadway sections with higher speed limits have become more ubiquitous, the increase in fatality risk has extended beyond these roadways. The increase in risk has been so great that it has now largely offset the beneficial effects of some other traffic safety strategies. State policy makers should keep this trade-off in mind when considering proposals to raise speed limits.     

Motor-vehicle safety in Europe and the USA: A public-health perspective

This article provides a public-health perspective on the motor-vehicle safety situation in Europe and in the United States. It will be argued that a prerequisite for such a perspective is the use of fatality rate per capita, instead of the usually employed rate per distance traveled. To illustrate the public-health perspective, two sets of analyses were performed. The first set of analyses compared motor-vehicle fatality rates to fatality rates from other causes of death. The second set contrasted the motor-vehicle fatality rates per population in different countries, providing information about traffic safety relative to other countries.     

Fatality and influence factors in high-casualty fires: A correspondence analysis

The technology of correspondence analysis was applied to high-casualty fire data in China. The aim of this study was to investigate the associations between fatality levels and influence factors that involve place, cause, time of day, month, year and province. The variable fatality in a fire has four levels: 3, 4-5, 6-9 and ?10. The results show that hotels, welfare houses and hospitals tend to be strongly associated with fatality level ?10. The fires caused by work-related tasks tend to precipitate a relatively high number of fatalities and are strongly associated with fatality level 6-9. Fires that occur in the daytime (8:00-19:59) are associated with higher fatalities than fires that occur at night (20:00-7:59). The months in the cold season, such as winter or the beginning of spring, tend to be associated with fatality levels 4-5, 6-9 and ?10. CA dynamically portrayed the fatality tendency over the past 8 years, and 2007 tended to be associated with fatality level ?10. Fatality characteristics of provinces are identified, and Beijing, Shandong and Jilin are strongly associated with fatality level ?10. To explore whether associations between influence factors and fatality levels of high-casualty fires in China resemble corresponding associations of HCFs in the United States, data on fires with fatality level ?5 in the two countries were collected. The results of four sets of comparisons indicate that the associations between influences and fatality levels in the two countries present contrasting features. Some practical applications are briefly discussed.     

Urban street structure and traffic safety

IntroductionThis paper reports the influence of road type and junction density on road traffic fatality rates in U.S. cities.MethodThe Fatality Analysis Reporting System (FARS) files were used to obtain fatality rates for all cities for the years 2005–2010. A stratified random sample of 16 U.S. cities was taken, and cities with high and low road traffic fatality rates were compared on their road layout details (TIGER maps were used). Statistical analysis was done to determine the effect of junction density and road type on road traffic fatality rates.ResultsThe analysis of road network and road traffic crash fatality rates in these randomly selected U.S. cities shows that, (a) higher number of junctions per road length was significantly associated with a lower motor- vehicle crash and pedestrian mortality rates, and, (b) increased number of kilometers of roads of any kind was associated with higher fatality rates, but an additional kilometer of main arterial road was associated with a significantly higher increase in total fatalities. When compared to non-arterial roads, the higher the ratio of highways and main arterial roads, there was an association with higher fatality rates.ConclusionsThese results have important implications for road safety professionals. They suggest that once the road and street structure is put in place, that will influence whether a city has low or high traffic fatality rates. A city with higher proportion of wider roads and large city blocks will tend to have higher traffic fatality rates, and therefore in turn require much more efforts in police enforcement and other road safety measures.Practical applicationsUrban planners need to know that smaller block size with relatively less wide roads will result in lower traffic fatality rates and this needs to be incorporated at the planning stage.     

论降低我国道路交通事故致死率的措施

阐述我国交通事故人身伤害的严重性 ,参照发达国家交通安全经验 ,提出了减轻伤害、降低交通事故致死率的措施     

Relationships of frontal offset crash test results to real-world driver fatality rates

In a study of the relationship between Insurance Institute for Highway Safety frontal offset crash test ratings and real-world fatality rates, there was a clear trend for better-rated vehicles to have lower driver fatality risk, although the correlation was not uniform across all vehicle groups or statistically significant in all cases. For all types of crashes combined, fatality rates per registered vehicle were generally lower for vehicles rated good than for vehicles rated poor, but rates for acceptable and marginal vehicles were not always within this range. A more precise examination of fatality risk was accomplished by comparing driver outcomes in fatal two-vehicle crashes. When a rated vehicle collided with a nonrated vehicle, the fatality risk for the rated vehicle driver was highest for poorly rated vehicles, then progressively smaller for vehicles with marginal, acceptable, or good ratings. For two-vehicle crashes of similar vehicles rated good and poor, the odds of driver fatality was 34 percent lower for the good vehicle than for the poor vehicle, but this estimate was not statistically significant. Finally, in head-on crashes of rated vehicles, the estimated odds of driver fatality was approximately 74 percent lower for the good vehicle than for the poor vehicle, with confidence limits ranging from 28 to 91 percent.     

Progress towards zero,an international comparison: Improvements in traffic fatality from 1990 to 2010 for different age groups in the USA and 15 of its peers

IntroductionIn January 2015, the United States Department of Transportation (USDOT) announced that the official target of the federal government transportation safety policy was zero deaths. Having a better understanding of traffic fatality trends of various age cohorts—and to what extent the US is lagging other countries—is a crucial first step to identifying policies that may help the USDOT achieve its goal.MethodIn this paper we analyze fatality rates for different age cohorts in developed countries to better understand how road traffic fatality patterns vary across countries by age cohort. Using benchmarking analysis and comparative index analysis based on panel data modelling and data for selected years between 1990 and 2010, we compare changes in the rate of road traffic fatality over time, as well as the absolute level of road traffic fatality for six age groups in the US, with 15 other developed countries.Results-ConclusionsOur findings illustrate tremendous variations in road fatality rates (both in terms of the absolute values and the rates of improvement over time) among different age cohorts in all of the 16 countries. Looking specifically at the US, our analysis shows that safety improvements for Youngsters (15-17 years old) was much better than for other age groups, and closely tracked peer countries. In sharp contrast, Children (0-14 years old) and Seniors (+65 years old) in the US, fare very poorly when compared to peer countries. For example, in 2010, Children in the US were a stunning five times more likely to experience a road traffic fatality than Children in the UK.Practical ApplicationsThis startling statistic suggests an immediate need to explore further the causes and potential solutions to these disparities. This is especially important if countries, including the US, are to achieve the ambitious goals set out in Zero Vision initiatives.     

Fatal occupational injuries in Jordan during the period 1980 through 1993

All fatal occupational injuries compensated by the Social Security Corporation (SSC) in Jordan during the period 1980–1993 were studied. Variables considered in the analysis included gender, age, nationality, occupation, salary, cause of injury, body part injured and cause of death. The overall fatality rate, of the 705 cases reviewed, was 25.5/100,000/year. The majority (98%) of fatalities were males. The risk of fatal injuries increased with age. Workers over 55 years, had the highest annual fatality rate (37.8). Immigrant workers had a higher fatality rate (32.26) than Jordanians (23.95). Unskilled workers constituted 58.3% of decedents and professionals had the highest fatality rate (52.9). Transportation sector had the highest fatality rate (122.4) followed by construction (50.6). Over the study period, fatality rates tended to decrease significantly in manufacturing, construction and trade economic sectors while no such trend was established by transportation, agriculture and services sectors. The leading causes of fatal injuries were motor-vehicle related accidents (63.0%) and fall of persons (11.1%). Head was the body part most injured and was involved in 46.6% of all deaths. Haemorrhage was the main reported cause of death (24.5%). It is concluded that intervention measures targeting specific occupations (transportation and construction) and causes of fatalities such as motor-vehicle incidents are needed.     

Estimates of fatal chest and abdominal injury prevention in side-impact crashes

The analysis reported in this study shows that the current NHTSA estimates of potential fatality reductions from improved side-impact protection in passenger cars are unrealistically high. This study is based on recent statistical estimates of fatality prevention by eliminating ejection and mitigating interior impact, and on an analysis of the limits of crash protection in fatal side-impact accidents. Because many fatalities involve high impact speed and significant deformation of vehicle side structures, about 70% of the near-side occupant fatalities from chest and abdominal injury are unpreventable by practical design changes. This implies that 30% of current fatalities may be prevented. Estimates of fatality prevention were then made as a fraction of the effectiveness of airbags in frontal crashes. Assuming sideinterior changes that may produce 20% of frontal airbag effectiveness, which is 6% effectiveness and is roughly the same level of safety benefit achieved with the energy-absorbing steering system, 140 fatalities per year would be prevented in all types of side-impact crashes. This estimate is a realistic but formidable goal. It is in striking contrast with NHTSA projection of 1,185 fatality reductions with relatively straightforward design changes. Their projection exaggerates potential safety improvements.     

County-level prohibition and alcohol-related fatal motor vehicle accidents

The 50 states and the District of Columbia were grouped according to whether or not they had county-level alcohol prohibition. Several motor vehicle fatality rates were calculated for each type of jurisdiction, including the single-vehicle fatality rate (an index of alcohol-related motor vehicle accidents). In all cases, motor vehicle fatality rates for drivers in states with county-level prohibition were significantly greater than in nonprohibition states. This suggests that drivers residing in counties with prohibition are compelled to drive to adjacent counties or states to drink and consequently have increased involvement in motor vehicle accidents.     

Occupant Risk,Partner Risk and Fatality Rate in Frontal Crashes: Estimated Effects of Changing Vehicle Fleet Mass in 15 Years

The effect of vehicle fleet mass on car crash fatalities was estimated, using a new mathematical model to isolate vehicle mass from related factors like size, stiffness and inherent protection. The model was based on fatality risk data, impact speed, fleet mass distribution, and collision probabilities. The fleet mass distribution was changed over 15 years to (a) a homogeneous fleet of 1300 kg cars, (b) a bimodal fleet of 600 and 1600 kg cars, and (c) a 300 kg lighter fleet.

Occupant and collision partner fatality risks were estimated for the new fleets. The new fleets were achieved by various strategies, and the average fatality rate was calculated after and during the transition to the new fleet.Occupant fatality risk decreased and partner risk increased as occupants changed to a heavier car. The average fatality rate was 59% higher after the transition to a bimodal fleet mass, and 11 % lower for a homogeneous fleet. A 300 kg lighter fleet had a 8% higher fatality rale, but the strategy influenced the number of fatalities accumulated during the transition. The safest strategy to attain the lighter fleet was to reduce the mass of the heaviest cars first.

It was concluded that vehicle fleet mass significantly affects traffic safety. Downsizing consequences can be compensated for by improving inherent vehicle protection or reducing impact speed. The fatalities during downsizing can be limited by choosing an appropriate strategy.     

Trends in occupational injuries and fatality in Turkey

Introduction. The aim of this study was to evaluate the trend of occupational injuries in Turkey using epidemiologic criteria such as incidence mortality and fatality/all injuries recorded – rates. Materials and methods. Safety and health data were obtained from the Annual Statistic Books of the Social Insurance Institution (1988–2006) and Social Security Institution (2007–2011) of Turkey. Results. The results from the official data showed that although total employment is increasing the number of occupational injuries and incidence and mortality rates are decreasing. The results also demonstrate that occupational fatality/all injuries recorded – rate is increasing. The fatality/all injuries recorded – rate per 1000 injuries increased to 25.5 in 2011 from 8.6 in 1988. Each work day an average of five people died because of occupational injuries. Discussion and conclusions. The fatality/all injuries recorded – rate (the number of fatal cases per 1000 occupational injuries) is an important indicator of the injury rate for a country. Systems of occupational injury and illness surveillance constitute a critical resource for the management and reduction of occupational injuries and illness.     

Impact of human development on safety consciousness in construction

The International Labour Organization (ILO) reports that the risk of fatal occupational injuries in developing countries is almost twice as high as in developed countries, indicating a potential relationship between the fatality rates and the development level. The human development index (HDI), based on life expectancy, knowledge level and purchasing power parity, endorsed by the United Nations Development Programme, is a widely accepted measure of the development level. This study investigates the relationship between the HDI and the fatality rates reported by the ILO. A 23-country data set is used to demonstrate the general trend of the relationship followed by country-specific analyses for Australia, Spain, Hungary and Turkey. The study conducted is limited to fatal occupational injuries in construction, where the accidents are notoriously high. The results demonstrate a statistically significant inverse relationship between the fatality rates and the HDI.     

Prediction of probability of fatality due to brain injury in traffic accidents

Abstract

Objective: Fatal brain injuries result from physiological changes in brain tissues, subsequent to primary damage caused by head impact. Although efforts have been made in past studies to estimate the probability of brain injury, none of them involved prediction of such physiological changes. The goal of this study was to evaluate the fatality prediction capability of a novel approach that predicts an increase in intracranial pressure (ICP) due to primary head injury to estimate the fatality rate using clinical data that correlate ICP with fatality rate.

Methods: A total of 12 sets of head acceleration time histories were used to represent no, severe, and fatal brain injury. They were obtained from the literature presenting head kinematics data in noninjurious volunteer sled tests or from accident reconstruction for severe and fatal injury cases. These were first applied to a Global Human Body Models Consortium (GHBMC) head–brain model to predict nodal displacement time histories of the brain, which were then fed into FEBio to predict ICP. A Weibull distribution was applied to the data for the relationship between fatality rate and ICP obtained from a clinical paper to estimate fatality rate from ICP (procedure A). Fatality rate was also estimated by applying the temporal and spatial maximum value of maximum principal strain (MPS_max) obtained from the GHBMC simulation to an injury probability function for MPS_max (procedure B). Estimated fatality rates were compared between the 2 procedures.

Results: Both procedures estimated higher average fatality rate for higher injury severity. The average fatality rate for procedure A without ischemia representation and procedure B was 72.4 and 51.0% for the fatal injury group and 8.2 and 21.7% for the severe injury group, respectively, showing that procedure A provides more distinct classification between fatal and nonfatal brain injury. It was also found that representation of ischemia in procedure A provides results sensitive to injury severity and impact conditions, requiring further validation of the initial estimate for the relationship between brain compression and ischemic cell death.

Conclusions: Prediction of the probability of fatality by means of a combination of simulations of the primary brain deformation and subsequent ICP increase was found to be more distinct compared to the prediction of primary injury alone combined with the injury probability function from a past study in the select 12 head impact cases.     

Effect of enhanced seat belt reminders on driver fatality risk

Objective

Enhanced seat belt reminders in automobiles have been shown to increase belt use rates by approximately 3 percentage points. The objective of this study was to estimate the effect of enhanced seat belt reminders on driver fatality risk.

Method

Data included all passenger vehicle driver deaths and vehicle registration counts in the United States for calendar years 2000-2007. Driver fatality rates per vehicle registration per year were compared for otherwise identical vehicle models with and without enhanced seat belt reminders.

Results

Driver fatality rates were 6% lower for vehicles with enhanced seat belt reminders compared with vehicles without enhanced belt reminders. After adjusting for vehicle age differences, the estimated effect of enhanced belt reminders on driver fatality risk ranged from a 9% reduction for General Motors vehicles to a 2% increase for Honda vehicles. Combining all manufacturers, enhanced belt reminders reduced fatality risk by approximately 2%. Although not statistically significant, the 2% reduction in fatality risk agrees with what should be expected from a 3 percentage point increase in seat belt use rates.

Conclusions

Enhanced seat belt reminders have raised driver belt use rates and reduced fatality rates, but more aggressive systems may be needed for some drivers. It can be inferred that nonfatal injury rates also have been reduced.

Impact on Industry

Manufacturers should be encouraged to put enhanced seat belt reminders on all vehicles as soon as possible.     

Regional economic conditions and crash fatality rates--a cross-county analysis

INTRODUCTION: Most studies that evaluate the relationship between economic conditions and traffic fatalities focus on the time-series relationship between the two factors. This analysis considers the cross-sectional perspective by estimating the cross-county correlation between per capita income and fatalities per vehicle mile traveled (VMT) in Ohio. METHOD: The empirical model employed in this analysis allows for interaction effects between per capita income and highway usage, in the determination of fatality rates. RESULTS: The resultant least squares estimates indicate that a significant interaction effect exists between per capita income and the percentage of highway VMT, indicating a nonlinear correlation between per capita income and fatality rates. This correlation rises as the proportion of VMT on highways rises, such that there is an inverse relationship with fatality rates when the highway share of county VMT is low and a direct relationship with fatality rates when the highway share of county VMT is high. Additionally, population density, the presence of interstate highways in rural counties, the prior prevalence of severe alcohol abuse, and the proportion of teen drivers all proved to be significant correlates with county fatality rates. CONCLUSIONS: These observations suggest factors that state and federal policy makers should consider when allocating resources that impact (whether directly or indirectly) traffic fatalities.