A pattern analysis of traffic crashes fatal to older drivers

A synthesis of the various crash circumstances in which older drivers die is lacking. This study is based on data from Sweden's national archive of fatal RTCs, and focuses on crashes in which the deceased driver was aged 65+ (2002-2004; n = 152). Crash patterns were identified by means of cluster analysis using a sub-set of 12 variables describing both driver and crash event characteristics. Crashes where the driver had died of natural causes prior to crash made up 19.7% of the cases (30 crashes) and were mainly single crashes. Four additional clusters were also identified. Two involved making left turns at intersections, one over-represented among men, occurring typically at weekends, in low-speed areas (30.6%), and the second one, over-represented among women, consisting of crashes in dry road conditions, and on intermediate-speed roads (21.5%). A third cluster included head-on and single-vehicle crashes occurring in dry road conditions but on high-speed roads (29.8%). The last cluster consisted of crashes occurring during the winter and on high-speed roads (18.2%). Older drivers die in traffic in various circumstances, sometimes prior to crashing. Some circumstances cannot be easily alleviated but others could, e.g., through modifications of the road traffic environment and car active safety measures that can help compensate for age-related shortcomings.     

Characteristics of traffic crashes in Maryland (1996-1998): differences among the youngest drivers

Motor vehicle crashes (MVCs) are the leading cause of death among teenagers in the US. The present study examines how crash rates and crash characteristics differed among drivers aged 16-21 in the state of Maryland from 1996 to 1998. The results show that, based on police reports. the youngest drivers have the highest rate of MVCs per licensed driver and per annual miles driven. Furthermore, crash characteristics suggest that inexperience rather than risky driving may account for the differing rates. Drivers closer to the age of 16 had their crashes under the safest conditions: during the day in clear weather while drinking less.     

Driving experience,crashes and traffic citations of teenage beginning drivers

Teenagers were surveyed by telephone every 6 months from their freshman to senior high school years (N=911). Self-reported crash involvements and citations were examined for each teenager's first year of licensure and first 3500 miles driven. Based on survival analysis, the risk of a first crash during the first month of licensure (0.053) was substantially higher than during any of the next 11 months (mean risk per month: 0.025). The likelihood of a first citation during the first month of licensure (0.023) also was higher than during any of the subsequent 11 months (mean risk per month: 0.012). Similarly, when viewed as a function of cumulative miles driven, the risk of a first crash or citation was highest during the first 500 miles driven after licensure. Fewer parental restrictions (e.g. no nighttime curfew) and a lower grade point average (GPA) were associated with a higher crash risk. Male gender, a lower GPA and living in a rural area were associated with a higher citation rate.     

Involvement of older drivers in multivehicle side-impact crashes

Side impacts were studied using three separate analyses. National Accident Sampling System (NASS) and National Crash Severity Study (NCSS) cases were reviewed on multivehicle crashes involving fatal chest and abdominal injury by interior contact. Twenty-five cases were analyzed and showed an unusually high involvement of older occupants. Analyses of the 1975-1986 FARS confirmed an overinvolvement. Sixty-four percent of near-side seated occupants were over 50 years old and 36% over 70 in fatal multivehicle side impacts. In contrast, 26% of victims in single-vehicle frontal crashes were over 50 and 8% over 70 years old. Analysis of the 1982-1986 NASS showed that single-vehicle side impacts are not an important injury risk for older drivers, except on icy or wet roads. In contrast, the risk of injury in multivehicle side impacts increases steadily with age and is a major problem for older drivers. The individual NASS and NCSS cases also showed that 88% of the multivehicle side crashes took place at an intersection and that the driver of the struck vehicle frequently caused the crash by driving error (48%) or traffic violation (16%). The majority of cases occurred in daylight hours, on dry roads, and without alcohol involvement. Changes in visual perception, judgment and attention of the older driver may be factors in their missing a traffic signal or turning in front of traffic under the right-of-way. In addition, a reduced tolerance to impact force probably contributes to the injury. Although an analysis of photographs of the side-impacted vehicle indicated that 44% had side-structure deformation that was similar to that produced in the National Highway Traffic Safety Administration (NHTSA) moving deformable barrier test, only 24%-32% of the cases actually addressed the proposed NHTSA dynamic side-impact test. The results of this analysis bear on the agency's preliminary regulatory impact analysis.     

Differences in accident characteristics among elderly drivers and between elderly and middle-aged drivers

A total of 5,853 elderly drivers, aged 55 and over, and 8,210 middle-aged drivers 36-50 years old, all of whom were involved in accidents during 1986, were compared using discriminant function and univariate techniques. Substantial differences were found in accident characteristics not only between middle-aged and elderly drivers but also between three different age groups of the elderly. Support was found for the suspicion that, while the elderly have fewer accidents than younger drivers, their safety record, based on driving exposure with noncrash convictions as a surrogate measure of kilometres driven, is worse, and, in addition, they are more often at fault in accident involvements.     

Sleep-related car crashes: risk perception and decision-making processes in young drivers

The aim of the present study is to analyse factors affecting worries, coping strategies and decisions of young drivers regarding the risk of sleep-related car crashes. Furthermore, the study also analyses whether framing the same information about sleepiness in two different linguistic forms influences: (1) the evaluation of the level of risk associated to a specific level of drowsiness (Attribute Framing problem); (2) the willingness to enact strategies to "prevent" sleepiness before night-time driving (Goal Framing problem); (3) the choice between two different ways, both of equal expected efficacy, of lowering drowsiness (Risky decision-making Framing problem). Six hundred and ninety-five young drivers [(57.6% females, 42.4% males); mean age 20.85 years (S.D.=1.2)] answered questions on drive risk perception and sleepiness, on nocturnal driving experience and on the strategies to deal with driver sleepiness, responding to one of the two different versions of the framed problems. A sub-sample of 130 participants completed the framed problems in both versions. The results show that experiences of sleep attacks and nocturnal driving frequency in the past 6 months affect both risk perception and the preventive strategies adopted. Furthermore, the manipulation on two out of the three problems (attribute and risky decision-making frames) significantly affected the respondents' evaluation.     

Declines in fatal crashes of older drivers: changes in crash risk and survivability

Objectives

Previous research has found that older driver fatal crash involvement rates per licensed driver declined substantially in the United States during 1997–2006 and declined much faster than the rate for middle-age drivers. The current study examined whether the larger-than-expected decline for older drivers extended to nonfatal crashes and whether the decline in fatal crash risk reflects lower likelihood of crashing or an improvement in survivability of the crashes that occur.

Methods

Trends in the rates of passenger vehicle crash involvements per 100,000 licensed drivers for drivers 70 and older (older drivers) were compared with trends for drivers ages 35–54 (middle-age drivers). Fatal crash information was obtained from the Fatality Analysis Reporting System for years 1997–2008, and nonfatal crash information was obtained from 13 states with good reporting information for years 1997–2005. Analysis of covariance models compared trends in annual crash rates for older drivers relative to rates for middle-age drivers. Differences in crash survivability were measured in terms of the odds of fatality given a crash each year, and the historical trends for older versus middle-age drivers were compared.

Results

Fatal crash involvement rates declined for older and middle-age drivers during 1997–2008 (1997–2005 for the 13 state subsample), but the decline for drivers 70 and older far exceeded the decline for drivers ages 35–54 (37 versus 23 percent, nationally; 22 versus 1 percent, 13 states). Nonfatal injury crash involvement rates showed similarly larger-than-expected declines for older drivers in the 13 state subsample, but the differences were smaller and not statistically significant (27 percent reduction for older drivers versus 16 percent for middle-age drivers). Property-damage-only crash involvement rates declined for older drivers (10 percent) but increased for middle-age drivers (1 percent). In 1997, older drivers were 3.5 times more likely than middle-age drivers to die in police-reported crashes (6.2 versus 1.8 deaths per 1000 crashes), but this difference was reduced during the 9-year study period to 2.9 times, as the rate of older drivers dying in a crash declined (5.5 deaths per 1000 crashes in 2005) and the death risk remained relatively stable for middle-age drivers.

Conclusions

Contrary to expectations based on increased licensure and travel by older drivers, their fatal crash risk has declined during the past decade and has declined at a faster rate than for middle-age drivers. The decreased risk for older drivers appears to extend not only to nonfatal injury crashes but also to property-damage-only crashes, at least as reported to police in the 13 states included in the nonfatal injury analysis. Although insurance collision data suggest that overall crash risk of older drivers may not be changing relative to middle-age drivers, the current analysis indicates that the reduced fatality risk of older drivers reflects both less likelihood of being involved in a police-reported crash and greater likelihood that they will survive when they do crash.     

Factors affecting the severity of motor vehicle traffic crashes involving elderly drivers in Ontario

A population-based cross-sectional study was conducted to examine factors affecting the severity of motor vehicle traffic crashes (MVTCs) involving elderly drivers in Ontario. The study population included drivers aged 65 and over involved in injury-producing MVTCs between 1988 and 1993 on Ontario public roads. Information was obtained from the Canadian Traffic Accident Information Databank (TRAID) compiled from police reports. The severity of MVTC was classified as fatal, major, minor or minimal. Comparisons between fatal-, major-, minor- and minimal-injury crashes were conducted. Percentage distributions of crashes at each level of severity involving elderly drivers were examined according to specific factors and tested using the X2 test. Multivariate unconditional logistic regression was used to calculate the estimated relative risk as odds ratios (ORs) while controlling for confounding factors. A number of factors were significantly related to the increased risk of fatal-injury in crashes compared with a reference category for each variable. These included age (OR = 1.4 for 70-79 and OR = 2.3 for 80 + ), sex (OR = 1.4 for males), failing to yield right-of-way/disobeying traffic signs (OR = 1.7), non-use of seat belts (OR = 4.0), ejection from vehicle (OR = 11.3), intersection without traffic controls (OR = 1.7), roads with higher speed limits (OR = 7.9 for 70-90 km/h; OR= 5.8 for 100 km/h), snowy weather (OR= 1.6), head-on collisions (OR=55.1), two-vehicle turning collisions (OR = 3.1 for left-turn, OR = 8.7 for right-turn), overtaking (OR = 5.6), and changing lanes (OR = 2.1). Adverse medical/physical conditions increased the risk of fatality by a factor of 5 for drivers 75-79 years of age and a factor of 3.5 for those 80 years and over. However, in the age group 65-74, medical/physical condition did not appear to be related to risk of fatality. Similar but weaker associations between these factors and risk of major- and minor-injury in crashes were also observed. To reduce the severity of crashes involving elderly drivers, strategies could target specific factors such as head-on collisions, single-vehicle collisions, and traffic controls at intersections. Driver conditions such as medical/physical conditions and driver actions such as failing to yield right-of-way/disobeying traffic signs should be examined further.     

Merging into heavy motorway traffic by young and elderly drivers

An increase in the number of Heavy Goods Vehicles on motorways may lead to additional problems in the interaction with an increased number of elderly drivers. Elderly drivers suffer from reduced information processing speed and capacity, and in general effectively compensate for this by taking more time. However, this strategy, regulating task demands by slowing down will make merging into motorway traffic actually more difficult.In an experiment performed in a driving simulator, young and elderly drivers merged into motorway traffic. Driver behaviour and mental workload were studied while the following factors were manipulated: type of traffic and density of Heavy Goods Vehicles on the main road, the length of the acceleration lane, presence of a slowly driving lead car, and presence of a driver support system that encouraged the drivers to speed up if their speed was too low.Results show that the effects of an increased number of Heavy Goods Vehicles on the main road were not more adverse for elderly than for the young participants, with the exception that elderly drivers merged at a lower speed. This lower speed could make the manoeuvre more risky in real traffic. The support system and an extended acceleration lane facilitated merging, while a slowly driving lead car impeded completion of the manoeuvre.     

The involvement of drugs in drivers of motor vehicles killed in Australian road traffic crashes

A multi-center case-control study was conducted on 3398 fatally-injured drivers to assess the effect of alcohol and drug use on the likelihood of them being culpable. Crashes investigated were from three Australian states (Victoria, New South Wales and Western Australia). The control group of drug- and alcohol-free drivers comprised 50.1% of the study population. A previously validated method of responsibility analysis was used to classify drivers as either culpable or non-culpable. Cases in which the driver "contributed" to the crash (n=188) were excluded. Logistic regression was used to examine the association of key attributes such as age, gender, type of crash and drug use on the likelihood of culpability. Drivers positive to psychotropic drugs were significantly more likely to be culpable than drug-free drivers. Drivers with Delta(9)-tetrahydrocannabinol (THC) in their blood had a significantly higher likelihood of being culpable than drug-free drivers (odds ratio (OR) 2.7, 95% CI 1.02-7.0). For drivers with blood THC concentrations of 5 ng/ml or higher the odds ratio was greater and more statistically significant (OR 6.6, 95% CI 1.5-28.0). The estimated odds ratio is greater than that for drivers with a blood alcohol concentration (BAC) of 0.10-0.15% (OR 3.7, 95% CI 1.5-9.1). A significantly stronger positive association with culpability was seen with drivers positive to THC and with BAC > or =0.05% compared with BAC > or =0.05 alone (OR 2.9, 95% CI 1.1-7.7). Strong associations were also seen for stimulants, particularly in truck drivers. There were non-significant, weakly positive associations of opiates and benzodiazepines with culpability. Drivers positive to any psychoactive drug were significantly more likely to be culpable (OR 1.8, 95% CI 1.3-2.4). Gender differences were not significant, but differences were apparent with age. Drivers showing the highest culpability rates were in the under 25 and over 65 age groups.     

Accident risk and risk-taking behaviour among young drivers

This paper reviews the evidence relevant to the hypotheses that young (16-25) drivers are at greater risk of being involved in a casualty accident than older drivers and this greater risk is primarily a function of their propensity to take risks while driving. The first hypothesis is clearly supported by epidemiological research even when controlling for differences in the quantity and quality of road travel and driving experience. The second hypothesis is also supported by observational and self-report surveys of driving behaviour. Some of the research and theory bearing on risk perception and risk utility, possible mediators of risk-taking, is also reviewed.     

Comprehensibility of traffic signs among urban drivers in Turkey

Traffic signs are commonly used traffic safety tools, mainly developed to provide crucial information in a short time to support safe drive; but the success depends on their comprehensibility by the drivers. Also, a sudden change in the traditionally used and accepted signs can cause significant safety problem, as in the case of cancellation of red oblique bars in 2004 as a part of the European Union Harmonization Process of Turkey.     

Analysis of factors associated with injury severity in crashes involving young New Zealand drivers

Young people are a risk to themselves and other road users, as motor vehicle crashes are the leading cause of their death. A thorough understanding of the most important factors associated with injury severity in crashes involving young drivers is important for designing well-targeted restrictive measures within youth-oriented road safety programs. The current study estimates discrete choice models of injury severity of crashes involving young drivers conditional on these crashes having occurred. The analysis examined a comprehensive set of single-vehicle and two-vehicle crashes involving at least one 15–24 year-old driver in New Zealand between 2002 and 2011 that resulted in minor, serious or fatal injuries. A mixed logit model accounting for heterogeneity and heteroscedasticity in the propensity to injury severity outcomes and for correlation between serious and fatal injuries proved a better fit than a binary and a generalized ordered logit. Results show that the young drivers’ behavior, the presence of passengers and the involvement of vulnerable road users were the most relevant factors associated with higher injury severity in both single-vehicle and two-vehicle crashes. Seatbelt non-use, inexperience and alcohol use were the deadliest behavioral factors in single-vehicle crashes, while fatigue, reckless driving and seatbelt non-use were the deadliest factors in two-vehicle crashes. The presence of passengers in the young drivers’ vehicle, and in particular a combination of males and females, dramatically increased the probability of serious and fatal injuries. The involvement of vulnerable road users, in particular on rural highways and open roads, considerably amplified the probability of higher crash injury severity.     

Analgesics and road traffic crashes in senior drivers: An epidemiological review and explorative meta-analysis on opioids

Aim

To assess the epidemiological evidence associating the use of analgesics with the occurrence of road traffic crashes in senior drivers including a meta-analysis with specific focus on opioids.

Methods

Systematic literature review of articles published between 1991 and 2012 retrieved from major databases using relevant key words. Eligible articles were fully reviewed and the main characteristics and results summarized. The methodological quality was assessed using the Newcastle-Ottawa Scale. Heterogeneity tests and forest and funnel plots were used as part of the meta-analysis on opioids.

Results

From the potentially eligible articles, nine were selected (4 case–control, 1 case-crossover, and 4 cohort studies) of which four were of medium and five of high quality; seven investigated opioids and four non-steroidal anti-inflammatory drugs. Crash involvement (n = 7) rather than responsibility (n = 2) was investigated. Age and sex were the most common covariates adjusted for. Both opioids and non-steroidal anti-inflammatory drugs showed mixed results including differences across estimates between and within studies. A marginal positive effect was observed in the pooled analyses on opioids (n = 6, OR 1.20; 95% CI 1.08–1.32).

Conclusions

The evidence is unconvincing in terms of number of studies, control of major confounders, and consistency of the results. The effect seen for opioids can be attributed to the lack of adjustment of key confounders such as concomitant illness or the consumption of alcohol or other psychoactive medications. There is a need for more efficient designs like larger population-based retrospective cohorts and nested case–control or case-crossover studies based on registers of high quality allowing adjustment for these factors and for the selection of unequivocal outcomes (e.g. drivers’ responsibility) to produce more persuasive empirical evidence.     

Risky driving among young Australian drivers: trends, precursors and correlates

Young drivers are significantly over-represented among those injured or killed in road traffic accidents. Young adults' greater tendency to engage in risky driving behaviours has been implicated in their high crash involvement rate. While considerable research has examined the driving patterns of young adults and situational factors associated with their involvement in crashes, less is known about the characteristics or circumstances in young drivers' earlier lives that may have contributed to their current driving behaviour. This issue was explored using data from the Australian Temperament Project (ATP), a large longitudinal community-based study, which commenced in 1983 with 2443 families and has followed children's psychosocial development from infancy to early adulthood. During the most recent survey wave when participants were aged 19-20 years, information was collected from young adults about their driving experiences and behaviour. A series of analyses indicated that it was possible to distinguish a group of young adults who engaged in high risky driving behaviour (high group) from a group who engaged in low levels of risky driving behaviour (low group) from mid childhood. Young drivers with a tendency towards risky driving differed from others on aspects of temperament style, behaviour problems, social competence, school adjustment and interpersonal relationships. The implications of these findings for initiatives to reduce risky driving behaviour are discussed.     

Factors affecting the severity of work related traffic crashes in drivers receiving a worker's compensation claim

Aim

To examine factors that contribute to the severity of work related crashes in New South Wales, Australia.

Methods

Workers’ Compensation data was linked to police crash records for the period 1998-2002. Multivariate analysis was carried out to assess the relationship between relevant risk factors and the severity of injury (permanent disability or death) in drivers who had received a claim for a work related crash.

Results

Age, gender, occupation, duty status, vehicle type, licence status, fatigue, speeding and location of the crash were independently associated with the severity of the crash. Drivers aged 65 years and older were nearly twice (OR: 1.824, 95% CI: 1.106-3.007) as likely to be permanently injured or die as a result of a work related crash compared to the younger age group (15-24 years old). The risk to older drivers was even higher in crashes occurring while on duty. Drivers involved in traffic crashes while commuting were more likely to be severely injured (OR: 1.28, CI: 1.15-1.42) than those on duty. Compared to car drivers, taxi drivers were more than twice (OR: 2.38, CI: 1.726-3.296) as likely to be severely injured.

Conclusions

The findings contribute to bridging the gap in knowledge in the area of work related crashes and highlight the higher risk of permanent disability and death in older drivers, taxi drivers and commuters.     

Perception of the risk of an accident by young and older drivers

Young drivers are significantly overrepresented among all drivers involved in traffic accidents and fatalities. Excessive risk taking by young drivers appears to be largely responsible for this disproportionate involvement. This excessive risk taking could be due to being more willing to take risks than older drivers are, failing to perceive hazardous situations as being as dangerous as older drivers do or both causes. This paper reports the results of a study which attempted to determine whether misperception of risk could be an explanation for the high rates of traffic accidents among youth by testing whether young drivers perceive driving to be less hazardous than do older drivers. Three different methods of estimating the risk of accident involvement were used to compare risk estimates of young and older drivers. The methods included general questions about accident involvement, rating the riskiness of ten specific driving situations illustrated in still photographs, and rating the riskiness of fifteen videotaped driving situations. Young drivers perceived their own chances of an accident to be significantly lower than those of both their peers and older male drivers, while older male drivers saw their chances of accident involvement as comparable to those of their male peers and less than those of young male drivers. These findings lend support to the thesis that young male drivers are overrepresented in traffic accidents at least in part because they fail to perceive specific driving situations as being as risky as older drivers perceive them.     

An examination of the environmental,driver and vehicle factors associated with the serious and fatal crashes of older rural drivers

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 100 km/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.     

Driving strategies among younger and older drivers when encountering children

Results are presented of a study into how drivers say they behave and how they actually behave in traffic situations in which children are involved. An analysis was made of the most important types of encounters in which drivers become involved in accidents with children. On the basis of accident surveys and psychological theories on information processing, it was assessed by means of a questionnaire what knowledge drivers have concerning their own behavior in these situations, as well as their expectations about typical child behavior. Actual behavior of drivers in these situations was investigated by assessing video recordings of their behavior in driving a one hour standard track through residential areas. From the questionnaire it appeared that younger drivers reported more frequently dangerous behavior than older drivers. The recordings showed that younger drivers also behaved more dangerously during child encounters. This result could not be explained by differences in speed, but could by the fact that younger drivers detected the children less frequently than older drivers. Implications for the contents of mass media campaigns and their evaluation are discussed.     

Fragility and crash over-representation among older drivers in Western Australia

This study assessed age-related and gender differences in the relative contribution of fragility and crash over-representation to serious injuries per crash-involved driver in Western Australia. Police-reported crashes for the period 1998-2003 were extracted from the Western Australian Road Injury Database. For each passenger vehicle driver age and gender group, serious injuries per crash-involved driver and driver involvements in crashes per 100 million vehicle-kilometre travelled (VKT) were calculated as the respective measure of fragility and crash over-representation. Results from the decomposition method of analysis showed that older drivers over the age of 70 sustained serious injury rates more than twice as high as those of the 30-59-year-old drivers. Fragility increased with age, contributing between 47% and 95% for drivers above 65 years, but crash over-representation was the dominant factor for male drivers above 80 years. In contrast, fragility contributed little to the excess injury risk of younger drivers under the age of 30. The importance of fragility as a contributing factor to the inflated serious injury risk per vehicle-kilometre travelled for older drivers suggested that road safety initiatives should be directed towards the protection of vehicle occupants as well as screening for their driving ability.