Fatigue-related Crashes Research Articles

Prevention of Rear-End Crashes in Drivers with Task-Induced Fatigue through the Use of Auditory Collision Avoidance Warnings

Driver fatigue is associated with increased lane position variability, decreased response time and increased crash rate. Collision avoidance systems (CASs), which are currently installed in many vehicles, have been shown to reduce the crash rates of alert drivers. The current investigation examined the effectiveness of two auditory CAS warnings for reducing crash rates in fatigued young and older drivers faced with a potential rear-end collision. Relative to a no-warning condition, auditory CAS warnings reduced overall crash probability. The presence of a CAS warning was particularly beneficial to reducing crashes in older drivers. Results of this study indicate that auditory CAS warnings may help reduce fatigue-related rear-end crashes, particularly among older drivers.

Extended Work Shifts and the Risk of Motor Vehicle Crashes Among Interns

ABSTRACT It is not uncommon for interns in the United States to work extended shifts of 24 hours or longer. The marked increase in fatigue-related crashes and trucker deaths has been related to consecutive driving hours, prompting this survey of interns nationwide to detect any associations among work hours, extended shifts, and driving safety. A web-based survey was completed by 2737 interns, 80% of those receiving it. They completed 19,740 monthly reports of work hours, motor vehicle crashes, and near misses, as well as episodes of involuntary sleep. Participants were similar demographically to all interns matched through the National Resident Matching Program in 2002. Just over half the respondents were female. The mean age was 28 years. Nearly 80% were in medical specialties. The interns averaged 71 hours in the hospital each week and were awake for all but 3 hours. They spent an additional 4 hours weekly working or studying outside the hospital. Days off per month—including weekends, holidays, and allocated time off—averaged 6.5. The average number of extended work shifts per month was 4, and their average duration was 32 hours. In more than 85% of monthly surveys, the interns reported having worked extended shifts without night-float coverage. The longest time of continuous work averaged 28 hours. There were reports of 320 motor vehicle crashes, 133 of which were consequential (led to emergency treatment, caused at least $1000 in property damage, or prompted filing of a police report). The risk of a crash or near miss was significantly greater for interns commuting from work after an extended shift than after a nonextended shift. Every extended shift that was scheduled per month increased the monthly rate of motor vehicle crashes by 9% and increased crashes on the commute from work by 16%. The risk of falling asleep while driving or when stopped in traffic also rose significantly with the number of extended shifts per month. These findings indicate that interns commuting after an extended work shift are more than twice as likely to have a motor vehicle crash than those returning from a nonextended shift. This is a serious but preventable safety hazard for both the interns themselves and other motorists. Findings from other studies suggest that working an extended shift predisposes to failure of attention and to serious medical errors.

Trends of behavioral risk factors in motor vehicle crashes in Utah, 1992–1997

Objective: Measure changes in the prevalence of behavioral factors including police-reported fatigue and alcohol intoxication, as well as self-reported seatbelt use, and assess their effect on hospitalization or death after a motor vehicle crash. Methods: Probabilistic linkage was used to match drivers in motor vehicle crashes with hospital discharge records for the years 1992–1997. Frequencies of specific behavioral factors were evaluated using the Cochran–Armitage test for trend. Odds ratios and corresponding 95% confidence intervals were calculated using generalized estimating equations (GEEs) with crash and driver characteristics as independent variables and hospitalization or death as the dependent variable. Results: The analysis database consisted of 450,286 crash driver records, which linked to 4219 (0.9%) hospitalizations or deaths. There was an increasing trend for self-reported seatbelt use among crash-involved drivers from 80.5% in 1992 to 89.3% in 1997 ( P<0.001). Police-reported alcohol intoxication among crash-involved drivers showed a decreasing trend from 2.4% in 1992 to 1.5% in 1997 ( P<0.001). There was no trend for police-reported fatigue-related crashes. Odds ratios of hospitalization or death for seatbelt use, alcohol involvement, and fatigue were significant and did not fluctuate considerably between 1992 and 1997. Seatbelt use offered a protective effect from hospitalization or death, while alcohol intoxication and fatigue contributed to increased likelihood of hospitalization or death. Conclusions: These results suggest that while some improvement has been made in decreasing seatbelt non-use and driver alcohol intoxication among crash-involved drivers, no improvement has been made in reducing fatigue-related crashes.

Asleep at the Wheel: Spatial and Temporal Patterns of Fatigue-Related Crashes in Honolulu

As an island state located in the middle of the Pacific Ocean, where there is limited opportunity for long-distance driving, Hawaii provides an interesting context in which to study fatigue-related crashes. Data from the Hawaii Crash Outcome Data Evaluation System are used to analyze and map fatigue-related collisions. Injury outcomes of fatigue-related crashes are analyzed by using police crash data, emergency medical service records, and insurance claims records. There are distinct temporal and spatial patterns as well as relationships between fatigue-related crashes and driver characteristics. Recommendations for preventing fatigue-related crashes are developed. Roadway segments where fatigue-related crashes occur are identified as possible sites for various engineering treatments. Temporal and demographic information also can be used to design and implement more effective programs and systems for fatigue-related crashes.

The role of driver sleepiness in car crashes: a systematic review of epidemiological studies

To assess the available evidence for a causal role of driver sleepiness in car crashes or car crash injury, and to quantify the effect, a systematic review of the international literature was conducted. The review included all studies with a fatigue-related exposure measure, a crash or crash injury outcome measure and a comparison group, regardless of publication status, language or date of the study. Eighteen cross-sectional studies and one case-control study fulfilled the inclusion criteria. The fatigue-related exposures investigated in these studies were sleep disorders ( n=14), shift work ( n=2), sleep deprivation/fragmentation ( n=1), and excessive daytime sleepiness ( n=2). Only one study used an injury outcome measure. Studies were limited in their ability to establish a causal relationship by their design, by biases, and in many cases, by small sample sizes. The better quality cross-sectional studies were suggestive of a positive relationship between fatigue and crash risk, but could not provide reliable estimates of the strength of the association. The case-control study provided moderately strong evidence for an association between sleep apnoea and risk of driver injury, with an adjusted odds ratio of 7.2 (95% confidence interval 2.4–21.8). We conclude that the direct epidemiological evidence for a causal role of fatigue in car crashes is weak, but suggestive of an effect. To estimate the burden of injury due to fatigue-related crashes in the population, information is required from well-designed observational epidemiological studies about the prevalence of fatigue in the car driving population and the size of the risk this confers.

Patterns of stimulant drug use on Western Australian heavy transport routes

In July 1997, 236 truck drivers were interviewed at three truck stops in Western Australia. The interviews collected information on driver fatigue and stimulant drug taking as a fatigue countermeasure. Drivers have become more aware of fatigue as a problem within the industry over the past two years, however, 27% of drivers reported using stimulant drugs to combat driver fatigue. Interstate drivers use more prescription and illicit stimulant drugs to keep awake while intrastate drivers use more over the counter stimulants. Over the counter stimulants are not perceived as drugs by intrastate drivers because they are easily and legally obtainable and this is reflected within many of their responses. The most frequent way that drivers obtained stimulant drugs was through a doctor, a chemist or illegal prescription. Anecdotal evidence from the drivers suggests that increasing pressure from the public and the media to eliminate illegally prescribed stimulant use by drivers has made them harder to obtain. Therefore, without fatigue issues within the industry being addressed, an increase in street purchases of illicit stimulants may occur. Prohibition of stimulant drug use without changing industry practices eliminates a fatigue countermeasure and could lead to a serious increase in fatigue-related crashes. The results of this study will help to identify “at risk” groups of drivers who can be targeted for education on fatigue and drug issues.

From the NHTSA: Shift workers, teens most vulnerable to fatigue-related crashes

From the NHTSA: Shift workers, teens most vulnerable to fatigue-related crashes

Driver Fatigue and at Risk Groups: Significance for Health Educators

Driver fatigue has become a problem that deserves more attention. Each year driver fatigue kills at least 1,500 Americans, and the U.S. National Highway Traffic Safety Administration estimates that as many as 100,000 police-reported crashes are the result of driver fatigue. Researchers have identified certain groups that are most at risk of driver fatigue. These groups are rotating shift workers, truck drivers, sleep-disordered persons, and young adults. Health education may help decrease these driver fatigue-related crashes in these groups through educational interventions.