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It is often assumed that a child restraint with a five or six-point internal harness provides greater protection for children in frontal crashes than a booster seat with a lap-sash seat belt. However, most research comparing these restraint types has focused on protection for children aged up to approximately 3–4 years of age. Recently, harnessed child restraints for older children up to approximately 8 years of age have become available, but there is little data on their performance compared to booster seats for children over 4 years of age. This study aimed to compare frontal crash performance of a series of harnessed child restraints for children aged 4–8 years to booster seats. Four large harnessed child restraints (Type G in the Australian Standard, AS/NZS 1754:2013) and six high back booster seats (Type E in AS/NZS 1754:2013) were tested in frontal impact on a deceleration sled. Head and pelvis accelerations were recorded and head excursions were measured from high speed video. Head excursion was an average of 92 mm greater in the large harnessed child restraints than the high back booster seats. The initial position of the head in Type G restraints, an average of 58 mm further forward compared to Type E boosters, was the main contributor to the larger head excursion during impact. Conversely, peak head accelerations in the impact phase were, on average, 37.2 g lower in the large harnessed child restraints than the high back booster seats. These data suggest that recommendations for harnessed restraints and booster seats for children aged 4–8 years is not as obvious as is sometimes assumed. Harnessed restraints allow greater head excursion in frontal impacts, potentially increasing the chances of head impacts, especially in vehicles with limited clearance between the restraint and the seat in front. The likelihood, and types of, incorrect use that occur in each restraint type, the vehicle occupant space, and the restraint’s crash performance under ideal conditions should be considered in recommending restraints for these older children.

To compare how errors in child restraint use influence crash injury risk in rearward and forward-facing restraints for a 1-year old occupant. Three convertible child restraint systems (CRS) were subjected to frontal dynamic sled tests at 56 km/h in rearward-facing and forward-facing modes in a correct use (baseline) condition and in five incorrect use conditions: loose securing belt, loose harness, partial harness use, top tether slack, and three minor errors. Excursion, head, and chest 3 ms resultant acceleration, HIC15, and neck forces and moments of a Q1 anthropomorphic test device (ATD) seated in the restraints were measured. The effect of incorrect use on each outcome and restraint type was analyzed. The influence of errors varied across different outcome variables, the three restraints tested and orientation modes. Excursion increased in four of five incorrect use conditions in both rearward and forward-facing orientations. A very loose harness increased four of five outcome variables in at least one forward-facing restraint, whereas only excursion was increased when rearward-facing. Overall, there tended to be a more negative effect of incorrect use (demonstrated through increases in outcome variables compared to the baseline) in the forward-facing orientation. Overall, errors in use tended to have a larger negative impact on forward-facing restraints than rearward-facing restraints. Given the widespread nature of errors in use, this adds further weight to arguments to keep children rearward-facing to 12 months of age and older. The results also highlight a variation in response to errors across differently designed restraints, suggesting the influence of errors may be minimized by restraint design that is more resistant to errors.

To examine the effect of age on the dynamic performance of child restraint systems in frontal crashes.A sample of used (3-269 months from manufacture) and newly purchased child restraints were subjected to frontal crash simulations of more than 56 km/h and peak deceleration approximately 33 g on a deceleration sled. Restraints were monitored for evidence of damage before and after each impact. Anthropometric test device (ATD) head and chest responses and peak head excursions were recorded for rearward facing restraints using the Q1 ATD and for forward facing restraints and booster seats using the Q6 ATD. The influence of restraint age on peak 3 ms head acceleration, HIC15, head excursion, peak 3 ms chest acceleration and restraint damage were analyzed.In all impacts, the ATD remained within the restraint and secured to the test bench demonstrating the crash protection offered by the old and used restraints. There was no apparent relationship between ATD responses and restraint age for any restraint type. Older forward facing restraint systems had a very modest increase in forward head excursion (ROverall, degradation in restraint dynamic performance in older restraints, including some that are much older than the currently recommended 10-year lifetime, is minimal. However newer restraints may provide better protection due to marginal improvements in restraint design over time. Furthermore, the results of this study confirm previous recommendations that restraints should not be re-used after crash involvement.

Objective: Around a quarter of older occupants use some type of comfort or orthopedic aftermarket accessory on the vehicle seat while traveling in a vehicle. The aim of this study was to investigat...

Objective: Various definitions and uses of the term body region can be found in the literature. A definition of body regions using the Abbreviated Injury Scale (AIS) codes not strictly aligned with AIS chapters was developed for use in the European Commission-funded PIONEERS project (Protective Innovations of New Equipment for Enhanced Rider Safety). This work aims to examine the consequences of differently defined body regions on injury priority ranking using the percentage of patients showing at least moderate injury severity (AIS 2+) per regarded body region.Methods: Three different crash investigation data sets of injured riders and/or pillion riders of powered 2-wheelers (PTWs) were used for this analysis. The first contained data for 143 fatalities, the second contained data for 58 severely injured, and the last for contained data for 982 patients from a sample that was close to national representativeness. Frequency of injury was examined using body regions based on the AIS chapters (and first digit of the AIS Unique Identifier) and based on the PIONEERS definition.Results: Though different body region definitions did not result in different top-ranked body regions in terms of injury frequency, different definitions did provide different levels of information that impact priority within AIS chapter-defined regions. For PTW riders, cervical injuries are the highest priority spinal injuries. Thoracic and lumbar spinal injuries seem to occur together with other injuries in the thorax and abdominal region. Severe lower extremity injuries frequently involve the pelvis and the leg.Conclusions: Body regions need to be defined carefully to avoid misinterpretations. Publications that use body regions for their analysis to present injury frequencies should clearly define what they include in each region.

Objective: Cross-chest clips are widely used in North American child restraints but are less common in other countries, partially due to concerns over anterior neck contacts in frontal crashes. The...

Traffic crashes have high mortality and morbidity for young children. Though many specialized child restraint systems improve injury outcomes, no large-scale studies have investigated the cross-chest clip's role during a crash, despite concerns in some jurisdictions about the potential for neck contact injuries from the clips. This study aimed to investigate the relationship between cross-chest clip use and injury outcomes in children between 0 and 4 years of age.Child passengers between 0 and 4 years of age were selected from the NASS-CDS data sets (2003-2014). Multiple regression analysis was used to model injury outcomes while controlling for age, crash severity, crash direction, and restraint type. The primary outcomes were overall Abbreviated Injury Score (AIS) 2+ injury, and the presence of any neck injury.Across all children aged 0-4 years, correct chest clip use was associated with decreased Abbreviated Injury Scale (AIS) 2+ injury (odds ratio [OR] = 0.44, 95% confidence interval [CI], 0.21-0.91) and was not associated with neck injury. However, outcomes varied by age. In children12 months old, chest clip use was associated with decreased AIS 2+ injury (OR = 0.09, 95% CI, 0.02-0.44). Neck injury (n = 7, all AIS 1) for this age group only occurred with correct cross-chest clip use. For 1- to 4-year-old children, cross-chest clip use had no association with AIS 2+ injury, and correct use significantly decreased the odds of neck injury (OR = 0.49; 95% CI, 0.27-0.87) compared to an incorrectly used or absent cross-chest clip. No serious injuries were directly caused by the chest clips.Correct cross-chest clip use appeared to reduce injury in crashes, and there was no evidence of serious clip-induced injury in children in 5-point harness restraints.

Real-world driving studies, including those involving speeding alert devices and autonomous vehicles, can gauge an individual vehicle's speeding behavior by comparing measured speed with mapped speed zone data. However, there are complexities with developing and maintaining a database of mapped speed zones over a large geographic area that may lead to inaccuracies within the data set. When this approach is applied to large-scale real-world driving data or speeding alert device data to determine speeding behavior, these inaccuracies may result in invalid identification of speeding. We investigated speeding events based on service provider speed zone data.We compared service provider speed zone data (Speed Alert by Smart Car Technologies Pty Ltd., Ultimo, NSW, Australia) against a second set of speed zone data (Google Maps Application Programming Interface [API] mapped speed zones).We found a systematic error in the zones where speed limits of 50-60 km/h, typical of local roads, were allocated to high-speed motorways, which produced false speed limits in the speed zone database. The result was detection of false-positive high-range speeding. Through comparison of the service provider speed zone data against a second set of speed zone data, we were able to identify and eliminate data most affected by this systematic error, thereby establishing a data set of speeding events with a high level of sensitivity (a true positive rate of 92% or 6,412/6,960).Mapped speed zones can be a source of error in real-world driving when examining vehicle speed. We explored the types of inaccuracies found within speed zone data and recommend that a second set of speed zone data be utilized when investigating speeding behavior or developing mapped speed zone data to minimize inaccuracy in estimates of speeding.

Objective Misuse of child restraint systems is a widespread and long-standing problem impacting risk of injury and death in car crashes. Discomfort has been suggested as a causative factor for misuse, particularly in errors introduced by children while they use the restraints. However, the relationship between comfort and errors in use has never been studied. In this study we examine the reliability and sensitivity of a newly developed observational method for assessing comfort in children in vehicles. We then use this method to examine the relationship between comfort and errors in use of booster seats. Methods A novel method was developed for assessing comfort by counting fidgeting and postural adjustment behaviors to derive a Discomfort Avoidance Behavior (DAB) score. The sensitivity of the DAB score was examined by observing children in four different seating conditions designed as “comfortable” and “uncomfortable” (Part 1). Paired-samples t-tests were used to compare differences in DAB between seating conditions. The reliability of the DAB score was assessed by calculating the intraclass correlation coefficient (ICC) between DAB scores recorded by different researchers. The association between comfort and correctness of use was examined by observing children using booster seats (Part 2). The association between DAB score and number of usage errors was tested using linear regression analysis. Participants were children ages 4–8 years. Fourteen children participated in Part 1 and 15 children in Part 2. Results The DAB score was sensitive to changes in seat condition (p < 0.01), and was repeatable between different researchers (ICC 0.98, 95% confidence interval [CI] 0.954–0.991). Increases in DAB were associated with increases in the number of use errors among children using booster seats (errors in use = 3.89 × DAB − 2.18, p < 0.0001). Conclusion The DAB score is a reliable and valid measure of comfort of children in child restraints but could be improved by incorporating a measurement of postural positioning. Comfort, as characterized by fidgeting and postural adjustment behaviors, is associated with correct use of child restraints. The broader implication is that this confirms ergonomic design of child restraints as important for minimizing errors in use. There is a need for further study of the impact of specific restraint design features on comfort experienced by children.

Fractures are a common injury among motorcycle riders and can have serious health implications. Impact protection (IP) has been designed to help prevent fractures, yet there are conflicting opinions as to whether this IP does in fact help prevent fractures in real-world crashes. This work aimed to (1) use simulated dummy impacts to examine whether existing types of IP could reduce the force transferred to the underlying bone to below fracture tolerance levels and (2) investigate whether current European Standard (EN 1621-1) test procedures for impact protectors designed for motorcyclists are sufficient to ensure fracture protection.Twenty-three shoulder and 7 knee IP specimens were tested using a 23-kg impactor contacting axially along the clavicle and femur of an anthropomorphic test device (ATD) at an energy level corresponding to the fracture tolerance of these bones. Sixteen IP specimens were the same as those worn by motorcycle riders involved in crashes where injury outcome was known (knee: n = 3; shoulder: n = 13) and the IP had been previously tested to EN 1621-1. Other IP tested represented a wide range of IP available for purchase at a motorcycle accessory store. Double and triple layers of IP were also tested. Energy attenuated during the dummy impacts was compared to energy attenuated when tested to EN 1621-1.Of the 23 shoulder IP tested, the average percentage reduction of transferred force to the shoulder from the baseline test was 7.6 ± 4.8%. The percentage reduction of transferred force to the knee from the baseline was 43.9 ± 7.5%. The entire group of knee IP tested reduced the transferred force to the knee to below the 10-kN injury threshold for the femur. There was a positive but nonsignificant correlation between the ATD test and the EN 1621-1 impact test performance, suggesting that the European standard test method likely provides a good indication of IP performance. However, given the low correlation coefficient, the relationship between IP performance in the European standard test method and injury protection remains unclear.Though the energy attenuation test method in the European standard may be an appropriate approach, distinct differences in injury protection performance observed between knee and shoulder IP indicate that there may be a need for different performance criteria for IP designated to protect different body regions.

To conduct a process and impact evaluation of a multifaceted education-based pilot program targeting correct use of age-appropriate restraints in a regional setting with a high proportion of Aboriginal and Torres Strait Islander families.The program was delivered in 2010 in 3 early learning centers where 31 percent of the children were of Aboriginal and Torres Strait Islander descent. Each component of the program was assessed for message consistency and uptake. To measure program effectiveness, participating children were matched 1:1 by age, language spoken at home, and annual household income with 71 children from the control arm of a contemporaneous trial. The outcome measure in the control and program centers (a 4-category ordinal scale of restraint use) was compared using ordinal logistic regression accounting for age of the parent.Process evaluation found that though program components were delivered with a consistency of message, uptake was affected by turnover of all staff at one center and by parents experiencing difficulty in paying for subsidized restraints at each of the centers. Impact evaluation found that children from the centers receiving the program had nearly twice the odds of being in a better restraint category than children matched from the control group (adjusted odds ratio [ORadj] = 2.06, 95% confidence interval [CI], 1.09-3.90).This was a pragmatic study reflecting the real-life issues of implementing a program in preschools where 57 percent of families had a low income and turnover of staff was high. Despite these issues, impact evaluation showed that the integrated educational program showed promise in increasing correct use of age-appropriate restraints. The findings from this pilot study support the use of an integrated educational program that includes access to subsidized restraints to promote best practice child restraint use among communities that include a high proportion of Aboriginal and Torres Strait Islander families in New South Wales. Future trials in similar settings should consider offering more support in centers with high turnover of staff and offering alternative methods of payment when families experience financial difficulties in purchasing the subsidized restraints. If proven in larger trials, this approach could reduce death and injuries in child passengers in this vulnerable group.

This study aims to provide population estimates of incorrect restraint use among children aged 0-12 traveling in cars in New South Wales (NSW) and describe the errors occurring in different restraint types.Observations of randomly selected children and restraints were conducted in situ by trained researchers at sites statewide. Observation sites were randomly selected using a multistage stratified sample plan. Restraint use errors were recorded and analyzed by severity of error and restraint type using complex survey analysis techniques.One in two children was incorrectly restrained, and 38 percent in a serious manner. Multiple errors were common (31% of children). Both installation and "securing" errors were common, with installation errors more common in convertible restraints (rearward-facing/forward-facing restraints and forward-facing restraints/booster seats) than single-mode restraints (odds ratio [OR] 4.3; 95% confidence interval [CI] 1.7-10.8). Multiple errors were more common in convertible restraints (OR 3.6; 95% CI 1.9-7.0). The most frequently observed errors were excessive seat belt slack (25 mm), incorrect belt routing, nonengagement of the seat belt buckle, very loose harness (25 mm slack), harness off the shoulder, nonuse of belt guides, sash belt worn under the arm, and very twisted harnesses and belts (2 twists). For rearward- and forward-facing restraints the highest priorities in terms of frequency and degradation in crash protection are errors related to harness use. For booster seat users the most important are those related to correct seat belt and belt guide use. For seat belt users, errors related to correct positioning of the sash belt are key.The results indicate that many errors are currently occurring in the way children are using restraints, as well as problems associated with the way child restraint systems are installed in vehicles. Incorrect use is particularly problematic in convertible restraints (rearward-facing/forward-facing restraints and forward-facing restraints/booster seats). Different priorities, in terms of the frequency and potential degradation in crash protection due to incorrect use for different restraint types, exist and these are important for those designing countermeasures to this problem.

Motor vehicle crashes are one of the leading causes of child death and acquired disability. Child restraint systems (CRS) for vehicles are designed to provide specialized protection for child occupants in the event of a crash. However, the effectiveness of a CRS is critically dependent on: correct installation of the CRS in the vehicle, the correct harnessing of the child in the CRS, and use of an appropriate CRS. The current study aimed to investigate the incidence misuse and/or inappropriate use of CRS through a CRS inspection program in the Australian states of New South Wales (NSW), Victoria (VIC), Queensland (QLD), South Australia (SA), Western Australia (WA), and Tasmania (TAS).Participants were recruited through an advertisement for free CRS inspections displayed at childcare centers, kindergartens, community centers, hospitals, and child expos. At each inspection, the CRS fitting specialist inspected and reported to the owner of the CRS on the installation of the child restraint(s) and/or system(s) and any fitting faults and/or concerns with the fitting and/or use if the child restraint(s) and or system(s).The following results are based on the inspection of 1386 vehicles, in which there were 1995 restraints. Of all the restraints inspected, the majority (79%) were reported as having at least one instance of misuse. The most common forms of misuse included harness strap errors such as the straps being adjusted, faulty, twisted, and/or incorrectly positioned (38%); seat belt errors such as the seatbelt being incorrectly routed, twisted, and/or incorrectly adjusted (32%); missing or incorrect fitting of gated buckle/locking clip (23%); the need for a missing sash guide (8%); tether errors such as the tether being incorrectly routed and/or adjusted (7%); inappropriate use of a CRS for the size of the child (6%); anchor errors such as the anchor was fitted incorrectly or not the correct type (5%); and the H Harness(1) being used incorrectly (5%). In addition, there were significant differences across restraint types in terms of the proportion of restraints with CRS misuse or fitment errors, chi(2) (2) = 51.42, p0.001. The rate of misuse was highest for the forward-facing CRS (88%), compared to infant seats (67%) and booster seats or cushions (63%).The results show that CRS misuse and fitment errors are widespread in Australia. Based on the findings of this study, it is recommended that educational and awareness materials and programs that provide information on the safety benefits associated with correct CRS use (as well as the injury risk associated with CRS misuse) be developed for both parents and children.

The primary objective of this work was to examine variations in the level of crash protection provided by different models of high-back booster seats in frontal impact. Secondary objectives included examination of the influence that specific belt positioning features have on the ability of a booster to achieve and maintain good seat belt fit; and the relationship between dummy loads, motion, and belt fit, both statically (pre-impact) and dynamically (during impact).Seventeen different models of high-back booster seats were subjected to simulated frontal impacts on a rebound crash sled. The TNO P10 dummy, instrumented to measure head and chest accelerations and targeted to allow head motion tracking, was used in these tests. Three high-speed cameras were used to record dummy motion. Associations between pre-impact seat belt geometry, the dynamic seat belt fit, and dummy response were examined.Clear variations were observed in the level of protection provided by the booster seats tested. Specifically, there were variations in the ability to provide and maintain good seat belt fit. Only three of the seventeen booster seats provided good sash (shoulder) and lap belt fit during dynamic testing. All seventeen boosters had a "sash guide." Sash guide type did not appear to influence the dynamic belt fit. However, the location of the guide and ultimately where on the shoulder the sash was positioned pre-impact did influence the dynamic sash fit. Anti-submarine clips (ASCs) that work to position the lap belt low on the abdomen were also found to maintain good lap belt fit during the dynamic tests. However, two booster seats without ASCs were also able to maintain good dynamic lap belt fit, although the mechanism of this behavior is less clear. Though there was a relationship between head excursion, head acceleration and the pre-impact static position of the sash belt (shoulder belt), there was no relationship between dummy response and the overall ability of a booster seat to provide and maintain both good sash and lap belt fit.Booster seats aim to achieve a good seat belt fit for children too small to use the adult seat belt. Variations in dynamic seat belt fit observed among these seventeen commercially available booster seats demonstrate the need for regulatory protocols that incorporate assessment of dynamic seat belt fit. With current technologies, visual examination of the seat belt during dynamic testing is the best method for assessing this performance.