Estimating the human recovery costs of seriously injured road crash casualties.

Road crashes result in substantial trauma and costs to societies around the world. Robust costing methods are an important tool to estimate costs associated with road trauma, and are key inputs into policy development and cost-benefit analysis for road safety programmes and infrastructure projects. With an expanding focus on seriously injured road crash casualties, in addition to the long standing focus on fatalities, methods for costing seriously injured casualties are becoming increasingly important. Some road safety agencies are defining a seriously injured casualty as an individual that was admitted to hospital following a road crash, and as a result, hospital separation data provide substantial potential for estimating the costs associated with seriously injured road crash casualties. The aim of this study is to establish techniques for estimating the human recovery costs of (non-fatal) seriously injured road crash casualties directly from hospital separation data. An individuals' road crash-related hospitalisation record and their personal injury insurance claim were linked for road crashes that occurred in New South Wales, Australia. These records provided the means for estimating all of the costs to the casualty directly related to their recovery from their injuries. A total of 10,897 seriously injured road crash casualties were identified and four methods for estimating their recovery costs were examined, using either unit record or aggregated hospital separation data. The methods are shown to provide robust techniques for estimating the human recovery costs of seriously injured road crash casualties, that may prove useful for identifying, implementing and evaluating safety programmes intended to reduce the incidence of road crash-related serious injuries.

Injury risk for matched front and rear seat car passengers by injury severity and crash type: An exploratory study.

BACKGROUND: The risk of serious injury or death has been found to be reduced for some front compared to rear seat car passengers in newer vehicles. However, differences in injury severity between car occupants by seating position has not been examined. This study examines the injury severity risk for rear compared to front seat car passengers. METHOD: A retrospective matched-cohort analysis was conducted of vehicle crashes involving injured rear vs front seat car passengers identified in linked police-reported, hospitalisation and emergency department (ED) presentation records during 2001-2011 in New South Wales (NSW), Australia. Odds ratios were estimated using an ordinal logistic mixed model and logistic mixed models. RESULTS: There were 5419 front and 4588 rear seat passengers in 3681 vehicles. There was a higher odds of sustaining a higher injury severity as a rear-compared to a front seat car passenger, with a higher odds of rear seat passengers sustaining serious injuries compared to minimal injuries. Where the vehicle occupant was older, travelling in a vehicle manufactured between 1990 and 1996 or after 1997, where the airbag deployed, and where the vehicle was driven where the speed limit was ≥70km/h there was a higher odds of the rear passenger sustaining a higher injury severity then a front seated occupant. CONCLUSION: Rear seat car passengers are sustaining injuries of a higher severity compared to front seat passengers travelling in the same vehicle, as well as when travelling in newer vehicles and where the front seat occupant is shielded by an airbag deployed in the crash. Rear seat occupant protective mechanisms should be examined. Pre-hospital trauma management policies could influence whether an individual is transported to a hospital ED, thus it would be beneficial to have an objective measure of injury severity routinely available in ED records. Further examination of injury severity between rear and front seat passengers is warranted to examine less severe non-fatal injuries by car seating position and vehicle intrusion.

Comparison of novice and full-licenced driver common crash types in New South Wales, Australia, 2001-2011.

OBJECTIVE: To examine the circumstances of passenger vehicle crashes for novice licenced drivers aged 17-25 years and to compare the crash circumstances of the most common crash types for novices to a sample of full-licence drivers aged 40-49 years. METHOD: A retrospective analysis was conducted of passenger vehicle crashes involving novice and full-licenced drivers during 1 January 2001 to 31 December 2011 in New South Wales (NSW), Australia. RESULTS: There were 4113 injurious crashes of novice drivers. Almost half the novice driver crashes involved a single vehicle. Vehicle speed (33.2%), fatigue (15.6%) and alcohol (12.6%) were identified risk factors in novice driver crashes. Correspondence analysis for 4 common crash types for novice drivers revealed that the crash characteristics between novice and full-licenced drivers were similar. CONCLUSIONS: Similarities exist between novice driver and full-licenced driver crash risk for common crash types. Preventive strategies aimed at crash risk reduction for novice drivers may also benefit all drivers.

Risk factors associated with the severity of injury outcome for paediatric road trauma.

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.

Head and spine injuries sustained by motorcyclists in head-leading collisions with fixed roadside objects.

OBJECTIVE: Motorcyclist collisions with fixed objects account for a substantial proportion of fatalities in many countries. Biomechanically valid crash test protocols are required to assess the injury potential of different fixed objects to motorcyclists and/or to develop safety devices that ameliorate this injury risk. The aim of the present article is to provide field-observed injury data pertaining to motorcyclist head-leading collisions with fixed objects to assist in the development of crash test protocols. METHOD: The Australian National Coronial Information System was used to identify fatal motorcyclist head-leading collisions with fixed objects. Head and spine injuries were identified from the autopsy reports for these individuals. The head impact locations and injuries were used to infer impact orientations and corresponding injury mechanisms. RESULTS: A sample of 44 motorcyclists estimated to have impacted fixed objects in the head-leading orientation was identified. The analysis of autopsy reports indicated a predominance of basilar skull fractures, intracranial injuries to the frontal cerebrum and inferior aspects of the brain (brainstem and cerebellum), and upper cervical spine injuries. Analysis of head impact locations identified a predominance of impacts to the frontal and/or lateral aspects and when considered in combination with the injury mechanisms, a typical impact orientation of sliding in the prone position with head extension was inferred. CONCLUSIONS: The study results were used to suggest possible crash test protocols for motorcyclists sliding into fixed objects and/or safety devices designed to reduce the injury risk of fixed objects. The predominant orientation of lying prone with head extension led the authors to suggest a crash test using the motorcycle anthropomorphic test device (MATD) sliding prone. However, the occurrence of the supine orientation, albeit less frequent, indicates the utility of a crash test with an anthropomorphic test device (ATD) sliding supine. The 2 options are discussed, particularly with regard to appropriate injury assessment reference values.

Safe system approach to reducing serious injury risk in motorcyclist collisions with fixed hazards.

Collisions with fixed objects in the roadway environment account for a substantial proportion of motorcyclist fatalities. Many studies have identified individual roadway environment and/or motorcyclist characteristics that are associated with the severity of the injury outcome, including the presence of roadside barriers, helmet use, alcohol use and speeding. However, no studies have reported the cumulative benefit of such characteristics on motorcycling safety. The safe system approach recognises that the system must work as a whole to reduce the net injury risk to road users to an acceptable level, including the four system cornerstone areas of roadways, speeds, vehicles and people. The aim of the present paper is to consider these cornerstone areas concomitantly, and quantitatively assess the serious injury risk of motorcyclists in fixed object collisions using this holistic approach. A total of 1006 Australian and 15,727 (weighted) United States motorcyclist-fixed object collisions were collected retrospectively, and the serious injury risks associated with roadside barriers, helmet use, alcohol use and speeding were assessed both individually and concomitantly. The results indicate that if safety efforts are made in each of the safe system cornerstone areas, the combined effect is to substantially reduce the serious injury risk of fixed hazards to motorcyclists. The holistic approach is shown to reduce the serious injury risk considerably more than each of the safety efforts considered individually. These results promote the use of a safe system approach to motorcycling safety.

The rising burden of serious thoracic trauma sustained by motorcyclists in road traffic crashes.

In many countries increased on-road motorcycling participation has contributed to increased motorcyclist morbidity and mortality over recent decades. Improved helmet technologies and increased helmet wearing rates have contributed to reductions in serious head injuries, to the point where in many regions thoracic injury is now the most frequently occurring serious injury. However, few advances have been made in reducing the severity of motorcyclist thoracic injury. The aim of the present study is to provide needed information regarding serious motorcyclist thoracic trauma, to assist motorcycling groups, road safety advocates and road authorities develop and prioritise counter-measures and ultimately reduce the rising trauma burden. For this purpose, a data collection of linked police-reported and hospital data was established, and considerable attention was given to establishing a weighting procedure to estimate hospital cases not reported to police and fatal cases not admitted to hospital. The resulting data collection of an estimated 19,979 hospitalised motorcyclists is used to provide detailed information on the nature, incidence and risk factors for thoracic trauma. Over the last decade the incidence of motorcyclist serious thoracic injury has more than doubled in the population considered, and by 2011 while motorcycles comprised 3.2% of the registered vehicle fleet, one quarter of road traffic-related serious thoracic trauma cases treated in hospitals were motorcyclists. Motor-vehicle collisions, fixed object collisions and non-collision crashes were fairly evenly represented amongst these cases, while older motorcyclists were over-represented. Several prevention strategies are identified and discussed.

The protective effect of roadside barriers for motorcyclists.

OBJECTIVE: Roadside barriers are often deployed between road users and fixed hazards to protect users from injury. However, the United States and Australian Roadside Design Guides do not consider motorcyclists in the risk-based decision process for the deployment of a barrier, because the severity indices for barriers and fixed hazards were developed for passenger vehicles. The aim of the present article is to quantify the protective effect of barriers with regards to motorcyclist injury and to thereby inform the Roadside Design Guides as to the relative severity of roadside hazards and infrastructure for motorcyclists. METHOD: A retrospective case series study, using linked police-reported road crash and hospital admission data in New South Wales, Australia, from 2001 to 2009 was performed. Crude and adjusted relative risks of motorcyclist serious injury were determined for various fixed objects compared to barriers, using serious injury rates and multiple variable logistic regression. Calculated relative risks compared with guardrail for motorcyclists were compared with those determined from the United States and Australian Roadside Design Guides for passenger vehicle occupants. RESULTS: The study identified 1364 motorcyclists injured as a result of single-vehicle collisions with roadside barriers, trees, utility poles, and other fixed roadside infrastructure. Trees, posts, and utility poles were shown to provide significantly higher risks of serious injury to motorcyclists compared to barriers. This was also found to be true for serious injuries to particular body regions, such as the head, spine, and torso. The results for motorcyclists were in reasonable agreement with those derived from severity indices in the United States and Australian Roadside Design Guides for passenger vehicle occupants. CONCLUSIONS: Roadside barriers provide a significant reduction in the risk of serious injury to motorcyclists compared to various roadside hazards. The provisions in the United States and Australian Roadside Design Guides for passenger vehicle occupants are generally applicable to motorcyclists and support the prior and ongoing use of such guides for designing roadsides that reduce the risk of injury to motorcyclists. However, a more realistic estimation might be derived by increasing the severity indices for barriers by around 25 percent for motorcyclists.

Head injuries to restrained occupants in single-vehicle pure rollover crashes.

OBJECTIVE: Studies performed previously of seat-belted occupants in real-world passenger vehicle rollover-only crashes have identified the head as one of the body regions most often seriously injured. However, there have been few studies investigating how these head injuries occur in any detail. This study aims to investigate the characteristics and patterns of head injury to seat-belted occupants in real-world rollover-only crashes and to identify possible biomechanical mechanisms responsible for head injury to aid in the development of a dynamic rollover test protocol. METHODS: National Automotive Sampling System-Crashworthiness Data System (NASS-CDS) data were used to generate summary statistics and perform logistic regression analysis of restrained and contained occupants in U.S. pure trip-over rollover crashes. Specific information from selected CDS cases focused on identifying potential mechanisms and patterns of serious head injury and the rollover conditions under which the injury occurred are also presented. RESULTS: Twenty-one percent of seriously injured occupants in pure trip-over rollovers had a serious head injury. On average, occupants seated on the far side of the rollover sustained serious head injuries more frequently and were more likely to receive injuries to the inboard side of the head than near-side occupants. Serious head injuries appear to be decoupled from serious injuries to other body regions except for a relationship found between basal skull fractures and cervical spine fractures. Serious head injuries were sustained by some occupants who had less than 15 cm of roof crush above their seated position. CONCLUSIONS: Serious brain injuries appear to occur frequently as a result of loading to the periphery of the head from contact with the roof assembly. Two mechanisms of injury for basal skull fractures in rollover crashes were identified. The injury patterns and locations of contact to the head are sensitive to the seated position of the occupant.

The effectiveness of helmets in bicycle collisions with motor vehicles: a case-control study.

There has been an ongoing debate in Australia and internationally regarding the effectiveness of bicycle helmets in preventing head injury. This study aims to examine the effectiveness of bicycle helmets in preventing head injury amongst cyclists in crashes involving motor vehicles, and to assess the impact of 'risky cycling behaviour' among helmeted and unhelmeted cyclists. This analysis involved a retrospective, case-control study using linked police-reported road crash, hospital admission and mortality data in New South Wales (NSW), Australia during 2001-2009. The study population was cyclist casualties who were involved in a collision with a motor vehicle. Cases were those that sustained a head injury and were admitted to hospital. Controls were those admitted to hospital who did not sustain a head injury, or those not admitted to hospital. Standard multiple variable logistic regression modelling was conducted, with multinomial outcomes of injury severity. There were 6745 cyclist collisions with motor vehicles where helmet use was known. Helmet use was associated with reduced risk of head injury in bicycle collisions with motor vehicles of up to 74%, and the more severe the injury considered, the greater the reduction. This was also found to be true for particular head injuries such as skull fractures, intracranial injury and open head wounds. Around one half of children and adolescents less than 19 years were not wearing a helmet, an issue that needs to be addressed in light of the demonstrated effectiveness of helmets. Non-helmeted cyclists were more likely to display risky riding behaviour, however, were less likely to cycle in risky areas; the net result of which was that they were more likely to be involved in more severe crashes.

Thoracic injuries to contained and restrained occupants in single-vehicle pure rollover crashes.

Around one in three contained and restrained seriously injured occupants in single-vehicle pure rollover crashes receive a serious injury to the thorax. With dynamic rollover test protocols currently under development, there is a need to understand the nature and cause of serious thoracic injuries incurred in rollover events. This will allow decisions to be made with regards to adoption of a suitable crash test dummy and appropriate thoracic injury criteria in such protocols. Valid rollover occupant protection test protocols will lead to vehicle improvements that will reduce the high trauma burden of vehicle rollover crashes. This paper presents an analysis of contained and restrained occupants involved in single-vehicle pure rollover crashes that occurred in the United States between 2000 and 2009 (inclusive). Serious thoracic injury typology and causality are determined. A logistic regression model is developed to determine associations between the incidence of serious thoracic injury and the human, vehicle and environmental characteristics of the crashes. Recommendations are made with regards to the appropriate assessment of potential thoracic injury in dynamic rollover occupant protection crash test protocols.

Cervical and thoracic spine injury from interactions with vehicle roofs in pure rollover crashes.

Around one third of serious injuries sustained by belted, non-ejected occupants in pure rollover crashes occur to the spine. Dynamic rollover crash test methodologies have been established in Australia and the United States, with the aims of understanding injury potential in rollovers and establishing the basis of an occupant rollover protection crashworthiness test protocol that could be adopted by consumer new car assessment programmes and government regulators internationally. However, for any proposed test protocol to be effective in reducing the high trauma burden resulting from rollover crashes, appropriate anthropomorphic devices that replicate real-world injury mechanisms and biomechanical loads are required. To date, consensus regarding the combination of anthropomorphic device and neck injury criteria for rollover crash tests has not been reached. The aim of the present study is to provide new information pertaining to the nature and mechanisms of spine injury in pure rollover crashes, and to assist in the assessment of spine injury potential in rollover crash tests. Real-world spine injury cases that resulted from pure rollover crashes in the United States between 2000 and 2009 are identified, and compared with cadaver experiments under vertical load by other authors. The analysis is restricted to contained, restrained occupants that were injured from contact with the vehicle roof structure during a pure rollover, and the role of roof intrusion in creating potential for spine injury is assessed. Recommendations for assessing the potential for spine injury in rollover occupant protection crash test protocols are made.

Injury typology of fatal motorcycle collisions with roadside barriers in Australia and New Zealand.

Motorcyclists contribute significantly to road trauma around the world through the high incidence of serious injuries and fatalities. The role of roadside safety barriers in such trauma is an area of growing concern amongst motorcyclists, road authorities and road safety researchers and advocates. This paper presents a case series analysis of motorcyclists that were fatally injured following a collision with a roadside barrier during the period 2001-2006 in Australia and New Zealand. Injury profiles and severities are detailed, and associations with crash characteristics are investigated. It is shown that the thorax region had the highest incidence of injury and the highest incidence of maximum injury in fatal motorcycle-barrier crashes, followed by the head region. This is in contrast to fatal motorcycle crashes in all single- and multi-vehicle crash modes, where head injury predominates. The injury profiles of motorcyclists that slid into barriers and those that collided with barriers in the upright posture were similar. However, those that slid in were more likely to receive thorax and pelvis injuries.

Characteristics of single vehicle rollover fatalities in three Australian states (2000-2007).

An analysis of 2000-2007 single vehicle rollover fatalities in three Australian states was carried out using data from the Australian National Coroners Information System. In this paper, successive selection criteria were applied to the initial dataset to analyse:overall, rollovers accounted for 35% of all occupant fatalities in a single vehicle transport injury event. For these fatalities, the occupant was ejected or stayed contained in equal proportions. However, results showed strong disparities between the more urban and densely populated states of New South Wales and Victoria, compared to the Northern Territory in terms of crash type distribution and containment of the occupant. Differences were also found in rollover initiation, speed at initiation and number of turns. Overall, the strongest association of fatal neck/thoracic spine injuries with head injuries was found for the contained, restrained occupant. This analysis of single vehicle rollover fatalities is consistent with previous findings. It also shows that in Australia, strategies for rollover injury risk mitigation will need to take into account a broad range of characteristics to be effective.