Cyclist crash scenarios and factors relevant to the design of cyclist detection systems
MacAlister, Anna; Zuby, David S.
Proceedings of the 2015 International IRCOBI Conference on the Biomechanics of Injury
Cyclists are overrepresented among motor vehicle crash fatalities. Detailed information regarding common cyclist crash scenarios and relevant crash factors is crucial to the development of cyclist detection warning and crash avoidance systems that could prevent these crashes and fatalities. Motor vehicle-cyclist crash data from federally maintained national databases were used to identify common and fatal crash scenarios between cyclists and motor vehicles. The most common fatal crash modes involved the motor vehicle-cyclist movement combinations straight-in line, straight-crossing, and straight-against. The most common crash modes involved the movement combinations straight-crossing, turning-crossing, and turning-in line. Crashes that occurred in non-daylight conditions and on roads with speed limits of 40 mi/h and greater contributed to the greatest percentage of fatalities. Cyclist detection systems that function at high speeds and in both daylight and non-daylight conditions offer the greatest potential benefit. Effective cyclist detection systems designed to function in scenarios like the three common fatal crash modes and two additional most common crash modes could help mitigate or prevent up to 47% of crashes, 48% of injuries, and 54% of fatalities, potentially saving up to 363 lives annually.
Profile of fatally injured pedestrians and bicyclists in the United States with high blood alcohol concentrations
Eichelberger, Angela H.; Cicchino, Jessica B.; McCartt, Anne T.
Proceedings of the 20th International Conference on Alcohol, Drugs, and Traffic Safety (CD-ROM)
In the United States, little research has focused on the problem of alcohol impairment among pedestrians and bicyclists.
The aim of this study was to investigate the prevalence, trends, and characteristics of alcoholimpaired fatally injured pedestrians and bicyclists.
The study analyzed 1992-2011 data from the Fatality Analysis Reporting System (FARS), a census of U.S. fatal motor vehicle crashes. Personal characteristics, roadway type, and other factors were examined among fatally injured pedestrians and bicyclists 16 and older who had high blood alcohol concentrations (BACs).
The number of pedestrians killed in motor vehicle crashes decreased and the number of bicyclists killed in motor vehicle crashes increased among ages 16 and older during the study period; however, the percentages with high BACs changed little. Among fatally injured pedestrians, the percentage with BACs =0.08% was 39% in 1992 and 37% in 2011. Among fatally injured bicyclists, the percentage with BACs =0.08% was 26% in 1992 and 25% in 2011. During the most recent 5 years of data (2007-11), 20,326 pedestrians 16 and older were fatally injured, and 37% of them had BACs =0.08%. The percentage of fatally injured pedestrians with BACs =0.08% was higher among males (43%) and ages 21-49 (47-50%), on weekends (49%), and in crashes occurring at night, especially during midnight-2:59 a.m. (60%). During the most recent 5 years of data (2007-11), 2,907 bicyclists 16 and older were fatally injured in crashes with motor vehicles, and 26% of them had BACs =0.08%. The percentage of bicyclist deaths with BACs =0.08% was highest during midnight-2:59 a.m. (49%) and among ages 30-49 (34-36%).
A substantial proportion of fatally injured pedestrians and bicyclists had high BACs, and this proportion has changed little during the last two decades. To the extent that alcohol impairment of pedestrians and bicyclists contributes to their deaths, countermeasures addressing alcohol consumption among these groups are needed.
Beware the Ides of March?
Teoh, Eric R.
This article is in response to “Can Tax Deadlines Cause Fatal Mistakes?” by D.A. Redelmeier and C.J. Yarnell in CHANCE 26(2). The authors examined the hypothesis that increased stress stemming from the deadline for filing tax returns, usually April 15, affects the number of people involved in fatal crashes (drivers, passengers, pedestrians, bicyclists, motorcyclists, killed, injured, uninjured, unknown). They compared Tax Day with days one week before and one week after, which controls for day of week and seasonality. They found a 6% increase in the number of people involved in fatal crashes on Tax Day, relative to the comparison days. The difference was statistically significant, based on the assumptions of the test they used.
Protecting pedestrians and bicyclists: some observations and research opportunities
Williams, Allan F.
Insurance Institute for Highway Safety
Pedestrians and bicyclists are commonly referred to as “vulnerable road users,” because in collisions with motor vehicles the lack of a protective structure and differences in mass heighten their injury susceptibility. Protecting them is a challenge, because road systems typically have been built for motor vehicles, with little attention to those on foot or on bicycles who may wish to travel on or alongside roads, or cross them, or change direction at intersections.
Incidence, severity, and outcomes of brain injuries involving bicycles
Kraus, Jess F.; Fife, Daniel; Conroy, Carol
American Journal of Public Health
We performed a population-based study of bicycle-related brain injuries in San Diego, California, residents during 1981. Incidence rates among males were three times higher than for females and were highest at ages 10-14 years for males. Only one-third of bicycle-related brain injuries involved collision with a motor vehicle, and this proportion was independent of age or gender. Brain injuries from motor-vehicle collisions were more severe than those resulting from other causes. Over half the brain-injured bicyclists aged 15 and older who were blood alcohol tested were legally intoxicated.
Two fatal bicyclist injuries from extended rear view mirrors
Fife, Daniel; Davis, Jospeph; Tate, Lawrence
The Journal of Trauma
Rear view mirrors mounted on the sides of vans and small trucks may extend beyond the sides of the vehicles and pose a hazard to other road users. Case reports of two bicyclists fatally injured by extended rear view mirrors of small trucks are presented.
Fatal injuries to bicyclists: the experience of Dade County, Florida
Fife, Daniel; Davis, Jospeph; Tate, Lawrence; Wells, JoAnn K.; Mohan, Dinesh; Williams, Allan F.
The Journal of Trauma
Among 173 fatally injured bicyclists, the head or neck was the region most seriously injured in 86%. The frequency of injury to the head and neck region and the frequency of nonsurvivable (AIS 6) injury were highest among the cases aged 16 years or less. Vertebral fractures occurred most often in the highest cervical vertebra (C1) and progressively less often in lower vertebrae. The relationship between vertebral position and fracture likelihood is approximately log linear. Bicyclists with a relatively long time from injury to death tended to be older persons with survivable injuries. They often died from complications (pneumonia, pulmonary embolus) rather than directly from their injuries.
Factors in the initiation of bicycle-motor vehicle collisions
Williams, Allan F.
Archives of American Journal of Diseases of Children
In this study, 888 injury-producing bicycle-motor vehicle collisions were examined. On the basis of the movements of the vehicles involved, the bicyclist or the bicycle or both was probably responsible for the initiation of more than three fourths of the collisions. Bicyclist age was strongly related to probable responsibility for the collision. Through age 12, nine out of ten bicyclists were probably responsible for the collision; above age 12, probable responsibility decreased in proportion to age; and only 34% of the bicyclists aged 25 years or older were probably responsible. Collisions involving bicyclists in various age groups differed considerably in where, when, and how they occurred. The movements of the vehicles primarily involved in the initiation of the collisions were evaluated in terms of counter-measure planning.
Pedestrian deaths in Rio de Janeiro and Baltimore
Baker, Susan P.
Insurance Institute for Highway Safety
The pedestrian death rate for Rio was found to be four times the rate for Baltimore. In contrast to pedestrians killed in Baltimore -- most of whom were very young or elderly or intoxicated -- the majority in Rio were adults of working age who had not been drinking. For this latter group, the death rate in Rio was approximately twenty times the Baltimore rate. There are three major implications of this research. First, in Rio, a city where infectious diseases have traditionally been of paramount importance as a cause of death, motor vehicles' now claim far more lives, than dysentery, typhoid, meningitis, whooping cough, diphtheria, and polio combined. It is essential that the magnitude of the problem of vehicle-related deaths and injuries be recognized, and reflected in the allocation of needed funds and the attention of relevantly trained scientists. Second, the results have led to development of a concept that should be useful in many types of injury research: namely, that the presence of a substantial proportion of able-bodied persons among those injured or killed can point to unusual or excessive environmental hazards. Although such evidence is not definitive, when combined with relatively high death or injury rates it should suggest profitable avenues for research and eventually lead to preventive measures. Finally, it is suggested that wherever pedestrian deaths are numerous, 'consideration be given to a policy designed to ensure that pedestrians choose 'the safest way of coping with an environment they share with vehicles; namely, to establish safe routes that pedestrians will perceive to be easier and more attractive than the more hazardous alternatives.