Holistic pedestrian safety assessment for average males and females

Objective

An integrated assessment framework that enables holistic safety evaluations addressing vulnerable road users (VRU) is introduced and applied in the current study. The developed method enables consideration of both active and passive safety measures and distributions of real-world crash scenario parameters.

Methods

The likelihood of a specific virtual testing scenario occurring in real life has been derived from accident databases scaled to European level. Based on pre-crash simulations, it is determined how likely it is that scenarios could be avoided by a specific Autonomous Emergency Braking (AEB) system. For the unavoidable cases, probabilities for specific collision scenarios are determined, and the injury risk for these is determined, subsequently, from in-crash simulations with the VIVA+ Human Body Models combined with the created metamodel for an average male and female model. The integrated assessment framework was applied for the holistic assessment of car-related pedestrian protection using a generic car model to assess the safety benefits of a generic AEB system combined with current passive safety structures.

Results

In total, 61,914 virtual testing scenarios have been derived from the different car-pedestrian cases based on real-world crash scenario parameters. Considering the occurrence probability of the virtual testing scenarios, by implementing an AEB, a total crash risk reduction of 81.70% was achieved based on pre-crash simulations. It was shown that 50 in-crash simulations per load case are sufficient to create a metamodel for injury prediction. For the in-crash simulations with the generic vehicle, it was also shown that the injury risk can be reduced by implementing an AEB, as compared to the baseline scenarios. Moreover, as seen in the unavoidable cases, the injury risk for the average male and female is the same for brain injuries and femoral shaft fractures. The average male has a higher risk of skull fractures and fractures of more than three ribs compared to the average female. The average female has a higher risk of proximal femoral fractures than the average male.

Conclusions

A novel methodology was developed which allows for movement away from the exclusive use of standard-load case assessments, thus helping to bridge the gap between active and passive safety evaluations.

Cost-effectiveness of England's national 'Safe At Home' scheme for reducing hospital admissions for unintentional injury in children aged under 5

BACKGROUND

Injuries in children aged under 5 years most commonly occur in the home and disproportionately affect those living in the most disadvantaged communities. The 'Safe at Home' (SAH) national home safety equipment scheme, which ran in England between 2009 and 2011, has been shown to reduce injury-related hospital admissions, but there is little evidence of cost-effectiveness.

MATERIALS AND METHODS

Cost-effectiveness analysis from a health and local government perspective. Measures were the incremental cost-effectiveness ratio per hospital admission averted (ICER) and cost-offset ratio (COR), comparing SAH expenditure to savings in admission expenditure. The study period was split into three periods: T1 (years 0-2, implementation); T2 (years 3-4) and T3 (years 5-6). Analyses were conducted for T2 versus T1 and T3 versus T1.

RESULTS

Total cost of SAH was £9 518 066. 202 223 hospital admissions in the children occurred during T1-3, costing £3 320 000. Comparing T3 to T1 SAH reduced admission expenditure by £924 per month per local authority and monthly admission rates by 0.5 per local authority per month compared with control areas. ICER per admission averted was £4209 for T3 versus T1, with a COR of £0.29, suggesting that 29p was returned in savings on admission expenditure for every pound spent on SAH.

CONCLUSION

SAH was effective at reducing hospital admissions due to injury and did result in some cost recovery when taking into admissions only. Further analysis of its cost-effectiveness, including emergency healthcare, primary care attendances and wider societal costs, is likely to improve the return on investment further.

Emergency provider preference for powered intraosseous devices and satisfaction with features improving safety, reliability, and ease-of-use

BACKGROUND

Powered intraosseous (IO) systems are valuable devices for emergent situations, with limited data on user preferences. A simulation/survey-based study was conducted among emergency medical service (EMS) providers to evaluate attitudes toward general powered IO system features to measure preferences/satisfaction for the most-commonly used and a novel powered IO system (with a passive safety needle, battery life indicator, and snap-securement/dressing).

RESEARCH DESIGN AND METHODS

Forty-two EMS providers completed a simulated activity using both powered IO systems and a 30-item questionnaire, including multiple choice, free-text, ranking, and Likert-like questions. Ranking scores were reported using a scale of 0 (least important/satisfactory) to 100 (most important/satisfactory). Statistical significances were evaluated via Wilcoxon signed-rank sum test.

RESULTS

Providers indicated driver performance (mean score ± SD; 77.8 ± 27.5) and IO needle safety mechanism (63.1 ± 27.9) as the most important features. Participants reported significantly higher (p < 0.001) satisfaction with the novel IO system overall, and its needle safety, battery life indicator, securement/dressing, and ease-of-use. Powered driver performance satisfaction was similar and favorable for the novel (88.1 ± 18.2) and traditional (87.1 ± 15.3) systems.

CONCLUSIONS

These findings highlight the value of clinician/user input and demonstrate EMS providers are more satisfied with a powered IO system featuring design elements intended to enhance safety and ease-of-use.

Influence of a Lighting Column in the Working Width of a W-Beam Barrier on TB51 Crash Test

Road equipment, such as, e.g., road safety barriers and lighting columns, are subject to certification according to the EN1317 standard to be allowed for use on European roads. In engineering practice, due to the terrain conditions, there are cases where other road equipment is installed within the working width of road safety barriers. Such situations are not considered during the certification process. Hence, the aim of this study is to analyze the effect of a lighting column installed within the working width of the barrier on the results of the TB51 crash test. The full-scale crash test and numerical simulation of this event were conducted. In the full-scale crash test, as well as in the simulation, the lighting column prevented the barrier’s post from properly disconnecting from the guardrail, which resulted in the barrier failing to restrain and redirect the 13-t bus. The simulation was quantitatively compared to the experiment, where the correlation coefficient of ASI curves equaled 84%. The THIV curves differed significantly between the experiment and the simulation, which is explained within the paper. Next, simulations with and without the lighting column were compared. The ASI and THIV in the simulation without the column were 0.33 and 16.1 km/h, respectively. In the simulation with the column, the ASI and THIV were 0.44 and 17.7 km/h, respectively. The maximum roll angle of the vehicle in the simulation without the column was 2.01° and with the column was 5.96°. The main difference, however, was that the system without the lighting column within the working width of the barrier was capable of properly restraining and redirecting the vehicle. The specific mechanics underlying this behavior are described within the paper.

Experimental and Numerical Assessment of Supporting Road Signs Masts Family for Compliance with the Standard EN 12767

The analysis aimed to assess the passive safety of supporting masts for road signs in accordance with EN 12767. Experimental tests were carried out based on the requirements of the standard for the smallest and the largest constructions within the product family. Numerical models of crash tests were prepared for whole product family using the Finite Element Method in the LS-Dyna environment. Based on the comparison of the experimental tests and the numerical calculations, the usefulness of the numerical model for estimating the actual value of the Acceleration Severity Index (ASI) and the Theoretical Head Impact Velocity (THIV) was assessed. With the use of these relationships the values of ASI and THIV for masts not tested experimentally were estimated. It was confirmed that the analyzed masts met the requirements for the passive safety of structures set out in the standard EN 12767. It was possible since as a result of the impact, the mast column detached from the base, allowing the vehicle to continue moving. The behavior of the masts was primarily influenced by the destruction of the safety connectors. The paper presents the most important elements from the point of view of designing such solutions.

Terrain park feature compliance with Québec ski area safety recommendations

OBJECTIVES

The primary objective of this paper is to examine terrain park (TP) feature compliance with recommendations from a ski area industry guide (are TP features compliant with the guide?) and determine factors that could be associated with TP feature compliance in Québec ski areas (do factors influence TP feature compliance?), Canada. These recommendations on the design, construction and maintenance are provided by the Québec Ski Areas Association Guide.

METHODS

A group of two to four trained research assistants visited seven ski areas. They used an evaluation tool to assess the compliance of 59 TP features. The evaluation tool, originally developed to assess the quality of TP features based on the guide, was validated in a previous study. Compliance was calculated by the percentage of compliant measures within a given feature. The potential influence of four factors on compliance (size of the TP, size of the feature, snow conditions and type of feature) were examined using a mixed-effects logistic regression model.

RESULTS

The average TP feature compliance percentage was 93% (95% CI 88% to 99%) for boxes, 91% (95% CI 89% to 94%) for rails and 89% (95% CI 86% to 92%) for jumps. The logistic regression showed that none of the four factors examined were associated with TP feature compliance with the guide.

CONCLUSION

Our results suggest that TP features are highly compliant with the guide in Québec ski areas.

Using Bluetooth beacon technology to reduce distracted pedestrian behaviour: a cross-over trial study protocol

OBJECTIVE

Over 6400 American pedestrians die annually, a figure that is currently increasing. One hypothesised reason for the increasing trend is the role of mobile technology in distracting both pedestrians and drivers. Scientists and policy-makers have attended somewhat to distracted driving, but attention to distracted pedestrian behaviour has lagged. We will evaluate Bluetooth beacon technology as a means to alert and warn pedestrians when they approach intersections, reminding them to attend to the traffic environment and cross streets safely.

METHODS

Bluetooth beacons are small devices that broadcast information unidirectionally within a closed proximal network. We will place beacons at an intersection frequently trafficked by urban college students. From there, the beacons will transmit to an app installed on users' smartphones, signalling users to attend to their environment and cross the street safely. A cross-over trial will evaluate the app with 411 adults who frequently cross the target intersection on an urban university campus. We will monitor those participants' behaviour over three distinct time periods: (1) 3 weeks without the app being activated, (2) 3 weeks with the app activated and (3) 4 weeks without the app activated to assess retention of behaviour. Throughout the 10-week period, we will gather information to evaluate whether the intervention changes distracted pedestrian behaviour using a logistic regression to estimate the likelihood of key behavioural outcome measures and adjusting for any residual confounding. We also will test for changes in perceived risk. The trial will follow CONSORT (Consolidated Standards of Reporting Trials) statement guidelines, as modified for cross-over design studies.

CONCLUSION

If this program proves successful, it offers exciting implications for future testing and ultimately for broad distribution to reduce distracted pedestrian behavior. We discuss issues of feasibility, acceptability and scalability.

More aware, more protected: a cross-sectional study on road safety skills predicting the use of passive safety elements among Spanish teenagers

OBJECTIVE

This study had two objectives: first, to test the effects of sociodemographic variables, and the effects of three key road safety skills (knowledge-risk perception-attitudes) on the use of passive safety elements (PSEs) among teenagers; and second, to assess the differential impact of the study variables on PSEs use from a gender-based perspective.

SETTING AND PARTICIPANTS

This cross-sectional study was framed in the paradigm of primary care, and it involved students from several educational centres in Spain. A sample of 827 Spanish teenagers (52.4% females and 47.6% males) with a mean age of M=14.41-7 (12-19) years was used.

RESULTS

Through SEM modelling, we found that the use of PSEs is largely explained by psychosocial variables through the mediation of three road safety skills: risk perception (β=0.103^***), rule knowledge (β=0.095^*) and attitudes towards road safety (β=0.186^***). Furthermore, multigroup analyses showed that, although most variables explain the use of PSEs among teenagers in a similar way, key gender-based differences exist in this regard.

CONCLUSIONS

Road safety skills have a significant effect on the use of PSEs among Spanish teenagers, and gender explains some differences in the mechanisms which predict them. Also, in the study we discuss the need for strengthening school-based interventions aimed at helping this vulnerable group of road users acquire and develop positive behavioural competences.

A Review on Injury Mechanism of Intracerebral Hemorrhage in Vehicle Accidents

BACKGROUND

Intracerebral hemorrhage is one of the most common injuries in vehicle accidents. The aim of this paper is to survey the injury mechanism of intracerebral hemorrhage in vehicle accidents, including contusion, subarachnoid hemorrhage (SAH), subdural hematoma (SDH) and diffuse axonal injury (DAI).

METHODS

A condensed overview is given based on the published studies in biomechanical studies on intracerebral hemorrhage. Animal tests, cadaver tests, accident investigations and numerical simulation are the main method used for the mechanism studies.

RESULTS

Angular velocity and acceleration can be used to predict these injuries and they are the main causation of DAI. Intracranial pressure is the main causation of coup/contrecoup contusion. Shear stress and strain contribute to the rupture of bridging veins that result in SDH, SAH.

CONCLUSION

Injury mechanism of intracerebral hemorrhage in vehicle accidents is complicated that with multiple causations. In-depth works need to be carried out in mechanism studies especially for child head injuries.