Kinematic analysis of an unrestrained passenger in an autonomous vehicle during emergency braking.

Analyzing human body movement is a critical aspect of biomechanical studies in road safety. While most studies have traditionally focused on assessing the head-neck system due to the restraint provided by seat belts, it is essential to examine the entire pelvis-thorax-head kinematic chain when these body regions are free to move. The absence of restraint systems is prevalent in public transport and is also being considered for future integration into autonomous vehicles operating at low speeds. This article presents an experimental study examining the movement of the pelvis, thorax and head of 18 passengers seated without seat belts during emergency braking in an autonomous bus. The movement was recorded using a video analysis system capturing 100 frames per second. Reflective markers were placed on the knee, pelvis, lumbar region, thorax, neck and head, enabling precise measurement of the movement of each body segment and the joints of the lumbar and cervical spine. Various kinematic variables, including angles, displacements, angular velocities and accelerations, were measured. The results delineate distinct phases of body movement during braking and elucidate the coordination and sequentiality of pelvis, thorax and head rotation. Additionally, the study reveals correlations between pelvic rotation, lumbar flexion, and vertical trunk movement, shedding light on their potential impact on neck compression. Notably, it is observed that the elevation of the C7 vertebra is more closely linked to pelvic tilt than lumbar flexion. Furthermore, the study identifies that the maximum angular acceleration of the head and the maximum tangential force occur during the trunk's rebound against the seatback once the vehicle comes to a complete stop. However, these forces are found to be insufficient to cause neck injury. While this study serves as a preliminary investigation, its findings underscore the need to incorporate complete trunk kinematics, particularly of the pelvis, into braking and impact studies, rather than solely focusing on the head-neck system, as is common in most research endeavors.

The Evolution of Hand Injuries at a State's Only Level I Trauma Center: A Look From the 1980s Through the Global Pandemic.

BACKGROUND: The purpose of this study is to evaluate any changes to hand trauma in the past three decades and through the COVID-19 pandemic. We hypothesized that improved consumer safety regulations, changes in access to care, and the impact of a global pandemic, among other variables, have significantly influenced the mechanisms and treatment of hand injuries between the 1980s, 2010s (pre-COVID-19), and 2020s (post-COVID-19). METHODS: A retrospective single-center review was performed at the only level I trauma center in Mississippi, identifying all hand trauma consultations between 2012-2019 and 2020-2021, compared to aggregated data from 1989. RESULTS: Car accidents, gunshots, saw injuries, door injuries, and falls increased in 2012-2019 and 2020-2021 compared to 1989, whereas knife injuries, glass injuries, industrial injuries, and burns decreased. Crush injuries, de-gloving injuries, and lacerations with irregular edges were increased in recent cohorts, corresponding with increased amputations and tissue loss. Skin and subcutaneous injuries decreased in modern cohorts, corresponding with a decreased ability for primary skin repair and the need for more flaps. Additionally, while hospitalizations have increased, patients have improved follow-up. CONCLUSIONS: The nature of hand trauma has changed significantly over the past three decades. Increased numbers of cars and greater access to firearms might have led to increased rates of high-energy trauma, whereas burn and industrial injuries have decreased, potentially secondary to improved safety efforts. Despite increased overall hand trauma, time to treatment and follow-up have improved. Through this study, we can be more cognizant of the evolution of hand trauma in the modern era. This can allow improved access to care and further refine management to optimize functionality for hand injuries.

Do comparative judgements affect the perceived relevance of mobile phone road safety campaigns?

OBJECTIVE: Given the prevalence of illegal mobile phone use while driving and reliance upon messaging campaigns in deterring the behavior, there is a need to explore to what extent comparative judgements may influence desired outcomes of such campaigns. This exploratory study investigated (a) the perceived relevance and influence of different mobile phone road safety campaigns within a sample of Queensland motorists who reported using their mobile phone while driving and (b) if these varied depending on whether participants believed that their crash risk whilst using a phone was higher (comparative pessimism), lower (comparative optimism) or similar to the same-age and sex driver. METHODS: A total of 350 licensed drivers residing within Queensland (Australia) were included in this study, of which 200 reported using their hand-held phone on some occasion. Participation involved completing a 20-25 min online anonymous survey, which included viewing three mobile phone road safety campaigns (injury-based, sanction-based and humor) and responding to questions about the perceived relevance and impact of each campaign. RESULTS: A total of 64 (32%) participants displayed comparative optimism, 50 displayed similar judgements (25%) and 86 (43%) exhibited comparative pessimism. First, it was found that the injury-based campaign was perceived to be significantly more relevant than the humor campaign. Second, whilst the relevance of each campaign did not vary as a function of group membership, the campaigns were significantly less relevant to those displaying comparative optimism relative to those with similar judgements and comparative pessimism. Finally, the injury-based campaign was perceived to be significantly more influential than the other campaigns. However, overall, participants displaying comparative optimism believed that they would be less influenced by the campaigns compared to those with comparative pessimism. CONCLUSIONS: Although preliminary, these findings suggest that low perceptions of risk may dilute or extinguish the desired behavioral outcomes of mobile phone road safety campaigns. Nonetheless, experimental research is needed to examine these effects directly.

Ambulance Traffic Crashes in Japan: Characteristics of Casualties and Efforts to Improve Ambulance Safety.

BACKGROUND: An ambulance traffic crash not only leads to injuries among emergency medical service (EMS) professionals but also injures patients or their companions during transportation. We aimed to describe the incidence of ambulance crashes, seating location, seatbelt use for casualties (ie, both fatal and nonfatal injuries), ambulance safety efforts, and to identify factors affecting the number of ambulance crashes in Japan. METHODS: We conducted a nationwide survey of all fire departments in Japan. The survey queried each fire department about the number of ambulance crashes between January 1, 2017, and December 31, 2019, the number of casualties, their locations, and seatbelt usage. Additionally, the survey collected information on fire department characteristics, including the number of ambulance dispatches, and their safety efforts including emergency vehicle operation training and seatbelt policies. We used regression methods including a zero-inflated negative binomial model to identify factors associated with the number of crashes. RESULTS: Among the 726 fire departments in Japan, 553 (76.2%) responded to the survey, reporting a total of 11,901,210 ambulance dispatches with 1,659 ambulance crashes (13.9 for every 100,000 ambulance dispatches) that resulted in a total of 130 casualties during the 3-year study period (1.1 in every 100,000 dispatches). Among the rear cabin occupants, seatbelt use was limited for both EMS professionals (n = 3/29, 10.3%) and patients/companions (n = 3/26, 11.5%). Only 46.7% of the fire departments had an internal policy regarding seatbelt use. About three-fourths of fire departments (76.3%) conducted emergency vehicle operation training internally. The output of the regression model revealed that fire departments that conduct internal emergency vehicle operation training had fewer ambulance crashes compared to those that do not (odds of being an excessive zero -2.20, 95% CI: -3.6 to -0.8). CONCLUSION: Two-thirds of fire departments experienced at least one crash during the study period. The majority of rear cabin occupants who were injured in ambulance crashes were not wearing a seatbelt. Although efforts to ascertain seatbelt compliance were limited, Japanese fire departments have attempted a variety of methods to reduce ambulance crashes including internal emergency vehicle operation training, which was associated with fewer ambulance crashes.

Improper Restraint Use in Fatal Pediatric Motor Vehicle Collisions.

PURPOSE: Motor vehicle collisions (MVC) are the second leading cause of death in children and adolescents, but appropriate restraint use remains inadequate. Our previous work shows that about half of pediatric MVC victims presenting to our trauma center were unrestrained. This study evaluates restraint use among children and adolescents who did not survive after MVC. We hypothesize that restraint use is even lower in this population than in pediatric MVC patients who reached our trauma center. METHODS: We reviewed the local Medical Examiner's public records for fatal MVCs involving decedents <19 years old from 2010 to 2021. When restraint use was not documented, local Fire Rescue public records were cross-referenced. Patients were excluded if restraint use was still unknown. Age, demographics, and restraint use were compared using standard statistical methods. RESULTS: Of 199 reviewed cases, 92 met selection criteria. Improper restraint use was documented in 72 patients (78%). Most decedents were White (72% versus 28% Black) and male (74%), with a median age of 17 years [15-18]. Improper restraint use was more common among Black (92% vs 73% White, p = 0.040) and male occupants (85% vs 58% female, p = 0.006). Improper restraint use was lower in the Hispanic population (73%) compared to non-Hispanic individuals (89%), but this difference was not statistically significant (p = 0.090). CONCLUSION: Most pediatric patients who die from MVCs in our county are improperly restrained. While male and Black patients are especially high-risk, the overall dismal rates of restraint use in our pediatric population present an opportunity to improve injury prevention measures. TYPE OF STUDY: Retrospective Comparative Study. LEVEL OF EVIDENCE: Level III.

E-scooter accidents-epidemiology and injury patterns: 3-year results from a level 1 trauma center in Germany.

INTRODUCTION: Since the introduction of e-scooters in Germany in 2019, they are becoming more and more popular and associated injuries have increased significantly. The aim of this study was to assess the injury patterns after e-scooter accidents. MATERIALS AND METHODS: From May 2019 to October 2022, all consecutive patients who presented at our emergency department (ED) following e-scooter accidents were included in our study and retrospectively analyzed. RESULTS: A total of 271 patients were included in our study. The mean age was 33 years. 38% of the patients were female and 62% were male. Most common injuries were traumatic brain injuries in 38% of the patients together with fractures affecting the upper limb (17%). An operative treatment was necessary in 40 patients. Most of the patients presented at night and about 30% were under the influence of alcohol. CONCLUSIONS: Our study shows one of the largest cohort of patients suffering e-scooter accidents in Europe. Compulsory helmet use, stricter alcohol controls and locking periods could contribute significantly to safety.

Database Integration Correlates Street Crossing Design Strategies With Pedestrian Injury.

INTRODUCTION: Transportation databases have limited data regarding injury severity of pedestrian versus automobile patients. To identify opportunities to reduce injury severity, transportation and trauma databases were integrated to examine the differences in pedestrian injury severity at street crossings that were signalized crossings (SCs) versus nonsignalized crossings (NSCs). It was hypothesized that trauma database integration would enhance safety analysis and pedestrians struck at NSC would have greater injury severity. METHODS: Single-center retrospective review of all pedestrian versus automobile patients treated at a level 1 trauma center from 2014 to 2018 was performed. Patients were matched to the transportation database by name, gender, and crash date. Google Earth Pro satellite imagery was used to identify SC versus NSC. Injury severity of pedestrians struck at SC was compared to NSC. RESULTS: A total of 512 patients were matched (median age = 41 y [Q1 = 26, Q3 = 55], 74% male). Pedestrians struck at SC (n = 206) had a lower injury severity score (ISS) (median = 9 [4, 14] versus 17 [9, 26], P < 0.001), hospital length of stay (median = 3 [0, 7] versus 6 [1, 15] days, P < 0.001), and mortality (21 [10%] versus 52 [17%], P = 0.04), as compared to those struck at NSC (n = 306). The transportation database had a sensitivity of 63.4% (55.8%-70.4%) and specificity of 63.4% (57.7%-68.9%) for classifying severe injuries (ISS >15). CONCLUSIONS: Pedestrians struck at SC were correlated with a lower ISS and mortality compared to those at NSC. Linkage with the trauma database could increase the transportation database's accuracy of injury severity assessment for nonfatal injuries. Database integration can be used for evidence-based action plans to reduce pedestrian morbidity, such as increasing the number of SC.

Young drivers' early access to their own car and crash risk into early adulthood: Findings from the DRIVE study.

INTRODUCTION: Car ownership at early licensure for young drivers has been identified as a crash risk factor, but for how long this risk persists is unknown. This study examined crash hazard rates between young drivers with their own vehicle and those who shared a family vehicle at early licensure over 13 years. METHODS: The DRIVE study, a 2003/04 survey of 20,806 young novice drivers in New South Wales, Australia was used to link to police crash, hospital and death records up to 2016. The first police-reported crash and crash resulting in hospitalisation/death was modelled via flexible parametric survival analysis by type of vehicle access at baseline (own vs. shared family vehicle). RESULTS: After adjusting for covariates, drivers with their own vehicle at early licensure had an almost 30 % increased hazard rate for any crash after one year (95 % CI:1.16-1.42) compared with those who only had access to a family car and this attenuated but remained significantly higher until year 7 (HR: 1.1, 95 % CI: >1.00-1.20). For crashes resulting in hospitalisation or death, an almost 15-times higher hazard (95 % CI: 1.40-158.17) was observed at the start of follow up, remaining 50 % to year 3 (95 % CI:1.01-2.18). CONCLUSIONS: Parents and young drivers should be aware of the increased risks involved in car ownership at early licensure. Development of poorer driving habits has been associated with less parental monitoring at this time. Graduated Driving Licensing educators, researchers and stakeholders should seek to address this and to identify improved safety management options.

Surveillance methods and interventions implemented in American Indian and Alaska Native communities to increase child restraint device and seat belt use in motor vehicles: a systematic review.

BACKGROUND: American Indian/Alaska Native (AI/AN) children are disproportionately affected by injuries and deaths related to motor vehicle crashes. We aimed to synthesise published evidence on surveillance methods and interventions implemented in AI/AN communities and analyse characteristics that make them successful in increasing child restraint devices and seat belt use. METHODS: Studies were collected from the PubMed, Scopus, and TRID databases and the CDC Tribal Road Safety website, Community Guide, and Indian Health Service registers. Included studies collected primary data on AI/AN children (0-17) and reported morbidity/mortality outcomes related to child restraint devices or seat belt use. Studies with poor methodological quality, published before 2002, whose data were collected outside of the USA, or were non-English, were excluded. Checklists from the Joanna Briggs Institute were used to assess the risk of bias. In the synthesis of results, studies were grouped by whether a surveillance method or intervention was employed. RESULTS: The final review included 9 studies covering 72 381 participants. Studies conducted surveillance methods, interventions involving law enforcement only and multipronged interventions. Multipronged approaches were most effective by using the distribution of child restraint devices combined with at least some of the following components: educational programmes, media campaigns, enactment/enforcement of child passenger restraint laws, incentive programmes and surveillance. DISCUSSION: Although this review was limited by the number and quality of included studies, available resources suggest that we need multipronged, culturally tailored and sustainable interventions fostered by mutually beneficial and trusting partnerships. Continued investment in AI/AN road safety initiatives is necessary.

Advancing traffic safety through the safe system approach: A systematic review.

The Safe System Approach (SSA) has emerged as a comprehensive framework for enhancing traffic safety through system-wide interventions. This systematic review, conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, analyzes 82 relevant studies categorized based on the SSA pillars: safe road users, safe vehicles, safe speeds, safe roads, and post-crash care. The review provides insights into SSA's effectiveness in reducing road traffic fatalities and injuries, exploring implementation challenges and opportunities, including policy initiatives, institutional frameworks, and stakeholder collaborations. The findings highlight the potential for SSA to create a more forgiving and resilient transportation system, offering valuable guidance for policy decisions, future research, and interventions aimed at promoting safer road environments. SSA's comprehensive strategy for Safe Road Users encompasses considerations of road system design, behavior modification, and tailored measures for vulnerable users, showcasing its versatility in addressing diverse challenges. In the realm of Safe Vehicles, SSA actively involves manufacturers in a cycle of continuous improvement, rigorous testing, and collaborative efforts to establish new safety regulations. The emphasis on managing Safe Speeds, aligning with human parameters, and involving communities reflects SSA's adaptable nature and provides insights for establishing context-specific speed limits. SSA contributes significantly to Safe Roads through its implementation of innovative countermeasures, forgiving road designs, and the integration of emerging disciplines, resulting in a notable reduction in fatalities and injuries. In the domain of Post-Crash Care, SSA's integrated perspective fosters collaboration among emergency services, medical professionals, and the justice system. It addresses challenges through standardized approaches and information sharing, ensuring a comprehensive and unified approach to road safety. This review contributes to the ongoing efforts to prioritize safety and transform the transportation landscape on a global scale.

Buckle me up! A randomised controlled trial using a tablet-based emergency department intervention for child car safety education.

BACKGROUND AND OBJECTIVES: Correct child car restraint use significantly reduces risk of death and serious injury in motor vehicle crashes, but millions of US children ride with improper restraints. We created a tablet-based car restraint educational intervention using Computer Intervention Authoring Software (CIAS) and examined its impact on knowledge and behaviours among parents in the paediatric emergency department (PED). METHODS: This was a non-blinded, randomised controlled trial of parents of PED patients ages 0-12 years. Participants were evaluated for baseline car restraint knowledge and behaviour. The intervention group completed an interactive tablet-based module, while the control group received printed handouts on car restraint safety. After 1 week, both groups received a follow-up survey assessing changes in car restraint knowledge and behaviour. Logistic regressions determined predictors of knowledge retention and behavioural changes. Parents in the CIAS group were also surveyed on programme acceptability. RESULTS: 211 parents completed the study with follow-up data. There was no significant difference in baseline car restraint knowledge (74.3% correct in intervention, 61.8% in control, p=0.15), or increase in follow-up restraint knowledge. Significantly more intervention-group caregivers reported modifying their child's car restraint at follow-up (52.5% vs 31.8%,p=0.003), and 93.7% of them found CIAS helpful in learning to improve car safety. CONCLUSION: Parents had overall high levels of car restraint knowledge. Using CIAS led to positive behavioural changes regarding child car restraint safety, with the vast majority reporting positive attitudes towards CIAS. This novel, interactive, tablet-based tool is a useful PED intervention for behavioural change in parents. TRIAL REGISTRATION NUMBER: NCT03799393.

[Reassessment of the emergency medical service deployment indication catalogue after traffic accidents]. / Reevaluation des Notarzteinsatzindikationskataloges nach Verkehrsunfällen.

BACKGROUND: The emergency physician indication catalogue is based on outdated studies and provides limited guidance for alarm criteria following traffic accidents. Advances in vehicle safety technology and changes in available resources necessitate a re-evaluation of the indications. The aim of this retrospective registry study is to identify preclinically assessable variables for severe injuries sustained in traffic accidents. METHODS: A total of 47,145 individuals involved in accidents between 1 January 2000 and 31 December 2021 from the GIDAS database were included. Separate datasets for severe (AIS 3+) and minor injuries were evaluated. RESULTS: Ejection (PPV 80.6%), entrapment (PPV 75.6%), burning vehicles (PPV 57.1%), challenging rescue situations (PPV 56.3%), vehicle disintegration (PPV 51.6%), and amnesia (PPV 50.3%) indicated severe injuries among vehicle occupants. For vulnerable road users (motorcyclists, cyclists, pedestrians), helmet loss (PPV 61.1%), being run over/dragging (PPV 41.9%), opponent vehicle window breakage (PPV 35.8%), and subsequent collision with objects (PPV 31.1%) were also identified. The χ2-test revealed significant associations between the variables and severe injuries. Combined variables achieved PPV values above 82%. DISCUSSION: The current emergency physician indication catalogue provides limited preclinically detectable criteria and should be revised based on the objective registry data. Query models for emergency dispatchers should be tested.

Investigating the impact of HMI on drivers' merging performance in intelligent connected vehicle environment.

Intelligent Connected Vehicle (ICV) is considered one of the most promising active safety technologies to address current transportation challenges. Human-Machine Interface (HMI) plays a vital role in enhancing user driving experience with ICV technology. However, in an ICV environment, drivers may exhibit excessive reliance on HMI, resulting in diminished proactive observation and analysis of the road environment, and subsequently leading to a potential decrease in drivers' situational awareness. This reduced situational awareness may consequently lead to a decline in their overall engagement in driving tasks. Therefore, to comprehensively investigate the impact of HMI on driver performance in various ICV environments, this study incorporates three distinct HMI systems: Control group, Warning group, and Guidance group. The Control group provides basic information, the Warning group adds front vehicle icon and real-time headway information, while the Guidance group further includes speed and voice guidance features. Additionally, the study considers three types of mainline vehicle gaps, namely, 30 m, 20 m, and 15 m. Through our self-developed ICV testing platform, we conducted driving simulation experiments on 43 participants in a freeway interchange merging area. The findings reveal that, drivers in the Guidance group exhibited explicit acceleration while driving on the ramp. Drivers in the Guidance and Warning groups demonstrated smoother speed change trends and lower mean longitudinal acceleration upon entering the acceleration lane compared to the Control group, indicating a preference for more cautious driving strategies. During the pre-merging section, drivers in the Warning group demonstrated a more cautious and smooth longitudinal acceleration. The Guidance group's HMI system assisted drivers in better speed control during the post-merging section. Differences in mainline vehicle gaps did not significantly impact the merging positions of participants across the three HMI groups. Drivers in the Guidance group merged closest to the left side of the taper section, while the Control group merged farthest. The research findings offer valuable insights for developing dynamic human-machine interfaces tailored to specific driving scenarios in the environment of ICVs. Future research should investigate the effects of various HMIs on driver safety, workload, energy efficiency, and overall driving experience. Conducting real-world tests will further validate the findings obtained from driving simulators.

The Impact of the City of Miami's Decision to Revoke Electric Scooter Company Permits on Orthopedic Trauma at a Level I Trauma Center.

BACKGROUND: Since the introduction of electric-scooter (e-scooter) mobile applications, there has been a marked increase in e-scooter-related injury. On January 19, 2022, the City of Miami revoked permits to five major mobile applications for violation of safety protocols. OBJECTIVES: The purpose of our study was to assess the effects of this notice on the orthopedic patients seen at our corresponding Level I trauma center. METHODS: Institutional Review Board approval was obtained for this study. A retrospective chart review was performed including all patients with orthopedic injuries at our Level I trauma center between July 19, 2021 and July 19, 2022. These dates include 6 months prior to and after the major e-scooter operators ceased use in Miami. SPSS statistical software version 28.0.0 (SPSS, IBM, Armonk, NY) was utilized for all statistical analysis. RESULTS: There were 2558 patients in the prenotice cohort, and 2492 patients in the postnotice cohort. After the notice, there was a significant decrease in the number of patients that presented to our institution due to injuries caused by e-scooters (2.8% vs. 1.8% patients; p = 0.021). Patients with injuries caused by e-scooters had a significantly lower age (38 vs. 42, respectively; p = 0.034) and were more likely to be male (79.3% vs. 67.4% male, respectively; p = 0.007) than patients with other orthopedic injuries. CONCLUSION: This study demonstrates that the 2022 notice revoking the major mobile application operators from the City of Miami resulted in a significant decrease in the number of orthopedic cases due to e-scooter-related injury at the corresponding Level I trauma center.

Factors affecting injury severity in motorcycle crashes: Different age groups analysis using Catboost and SHAP techniques.

OBJECTIVE: Motorcycle crashes often result in severe injuries on roads that affect people's lives physically, financially, and psychologically. These injuries could be notably harmful to drivers of all age groups. The main objective of this study is to investigate the risk factors contributing to the severity of crash injuries in different age groups. METHODS: This Objective is achieved by developing accurate machine learning (ML) based prediction models. This research examines the relationship between potential risk factors of motorcycle-associated crashes using (ML) and Shapley Additive explanations (SHAP) technique. The SHAP technique further helped interpreting ML methods for traffic injury severity prediction. It indicates the significant non-linear interactions between dependent and independent variables. The data for this study was collected from the Provincial Emergency Response Service RESCUE 1122 for the Rawalpindi region (Pakistan) over three years (from 2017 to 2020). The Synthetic Minority Oversampling Technique (SMOTE) is employed to balance injury severity classes in the pre-processing phase. RESULTS: The results demonstrate that age, gender, posted speed limit, the number of lanes, and month of the year are positively associated with severe and fatal injuries. This research also assesses how the modeling framework varies between the ML and classical statistical methods. The predictive performance of proposed ML models was assessed using several evaluation metrics, and it is found that Catboost outperformed the XGBoost, Random Forest (RF) and Multinomial Logit (MNL) model. CONCLUSION: The findings of this study will assist road users, road safety authorities, stakeholders, policymakers, and decision-makers in obtaining substantial and essential guidance for reducing the severity of crash injuries in Pakistan and other countries with prevailing conditions.

Evaluation of a 3M (mistakes, mentoring, and mastery) training program for transfer of control situations in a level 2 automated driving system.

Drivers must actively supervise automation as it can only function in limited conditions. A failure to supervise the system has negative consequences in terms of missed requests to take over control and may cause crashes or jeopardize safety. The objective of this study is to determine the effect of a novel, 3M (Mistakes, Mentoring, and Mastery) training program on drivers' behavior while using level 2 driving automation systems. To achieve this, 36 participants were assigned randomly to three different training programs (3M training, User manual, and Placebo) and drove through scenarios on a fixed-based driving simulator. The results showed that drivers in the 3M training group took back control more effectively when the driving automation system reached its limits compared to drivers who received User manual or Placebo training. Drivers in the 3M training Group also had higher situation awareness and improved trust in automation. The results indicate that an interactive approach to training with regards to vehicle automation can help drivers more safely interact with automation systems.

Subjective awareness of sleepiness while driving in younger and older adults.

Understanding whether drivers can accurately assess sleepiness is essential for educational campaigns advising drivers to stop driving when feeling sleepy. However, few studies have examined this in real-world driving environments, particularly among older drivers who comprise a large proportion of all road users. To examine the accuracy of subjective sleepiness ratings in predicting subsequent driving impairment and physiological drowsiness, 16 younger (21-33 years) and 17 older (50-65 years) adults drove an instrumented vehicle for 2 h on closed loop under two conditions: well-rested and 29 h sleep deprivation. Sleepiness ratings (Karolinska Sleepiness Scale, Likelihood of Falling Asleep scale, Sleepiness Symptoms Questionnaire) were obtained every 15min, alongside lane deviations, near crash events, and ocular indices of drowsiness. All subjective sleepiness measures increased with sleep deprivation for both age groups (p < 0.013). While most subjective sleepiness ratings significantly predicted driving impairment and drowsiness in younger adults (OR: 1.7-15.6, p < 0.02), this was only apparent for KSS, likelihood of falling asleep, and "difficulty staying in the lane for the older adults" (OR: 2.76-2.86, p = 0.02). This may be due to an altered perception of sleepiness in older adults, or due to lowered objective signs of impairment in the older group. Our data suggest that (i) younger and older drivers are aware of sleepiness; (ii) the best subjective scale may differ across age groups; and (iii) future research should expand on the best subjective measures to inform of crash risk in older adults to inform tailored educational road safety campaigns on signs of sleepiness.

A Lightweight Pre-Crash Occupant Injury Prediction Model Distills Knowledge From Its Post-Crash Counterpart.

Accurate occupant injury prediction in near-collision scenarios is vital in guiding intelligent vehicles to find the optimal collision condition with minimal injury risks. Existing studies focused on boosting prediction performance by introducing deep-learning models but encountered computational burdens due to the inherent high model complexity. To better balance these two traditionally contradictory factors, this study proposed a training method for pre-crash injury prediction models, namely, knowledge distillation (KD)-based training. This method was inspired by the idea of knowledge distillation, an emerging model compression method. Technically, we first trained a high-accuracy injury prediction model using informative post-crash sequence inputs (i.e., vehicle crash pulses) and a relatively complex network architecture as an experienced "teacher". Following this, a lightweight pre-crash injury prediction model ("student") learned both from the ground truth in output layers (i.e., conventional prediction loss) and its teacher in intermediate layers (i.e., distillation loss). In such a step-by-step teaching framework, the pre-crash model significantly improved the prediction accuracy of occupant's head abbreviated injury scale (AIS) (i.e., from 77.2% to 83.2%) without sacrificing computational efficiency. Multiple validation experiments proved the effectiveness of the proposed KD-based training framework. This study is expected to provide reference to balancing prediction accuracy and computational efficiency of pre-crash injury prediction models, promoting the further safety improvement of next-generation intelligent vehicles.

Do crashed drivers need more drug testing? A retrospective analysis of blood samples from hospitalised post-crash drivers in New Zealand.

Driving under the influence of alcohol and other drugs is a prominent safety concern in New Zealand and across the world. While alcohol testing is routinely performed for drivers involved in hospitalisation crashes, testing for other drugs is often not undertaken. The present study refers to 530 traffic crashes that occurred from October 2019 to January 2020 on New Zealand roads. The blood samples from 550 drivers who were injured in a crash and were admitted to a hospital (66% of all drivers involved in these crashes), previously tested for drugs and/or alcohol, were retested for a wider range of drugs. Alcohol above the applicable limit was found to be present in 38% of hospitalised drivers, while other drugs of interest were found in 47% of hospitalised drivers. Binary logistic regression was used to predict the presence of drugs of interest for a crashed driver using previous offence data. A driver having at least one prior drink and drug driving offence is 61% more likely to be positive for a drug of interest when involved in a crash. Similarly, a driver having at least one prior non-traffic drug offence is 4.7 times more likely to be positive for at least a drug of interest when involved in a crash. While the presence of a drug or drugs cannot be presumed to have played a role in the occurrence of the crash, this study has provided a unique and comprehensive picture of the presence of various drugs present in New Zealand drivers' blood. It is recommended to consider standardising drug testing on all blood specimens taken in relation to a serious injury or fatal crash. This procedure is not only of interest for information purposes but may importantly inform appropriate charging decisions.

Pediatric Fractures Associated With Riding Bicycles: A National 20-year Analysis.

BACKGROUND: Biking is a popular childhood activity with an intrinsic risk of injury. While advocacy groups have promoted protective equipment to help mitigate these risks, trends in the national health burden of fractures associated with biking in the pediatric population have not been explored in depth. METHODS: The National Electronic Injury Surveillance System database was queried between 2001 and 2020 to identify patients aged 18 years or below with fractures presenting to US emergency departments associated with riding bicycles. The patient narratives were analyzed to exclude patients not actively riding bicycles and to note helmet use and collisions with motor vehicles (MVs). RESULTS: A total of 33,955 fractures were identified in the database, representing an estimated 1,007,714 fractures from 2001 to 2020, or 50,331 fractures annually. Linear regression noted a significant decrease in fractures over the period ( R2 =0.899; P <0.001). Most fractures occurred in patients who were male (71.8%, 95% CI: 70.4% to 73.2%), White (53.1%, 46.0% to 60.0%), and aged 10 to 12 (30.6%, 29.6% to 31.7%) or 13 to 15 years (24.8%, 23.4% to 26.2%). Fractures occurred most frequently in the forearm (25.2%, 22.8% to 27.8%), wrist (21.2%, 19.5% to 22.9%), and shoulder (10.5%, 9.7% to 11.3%). Patients who sustained fractures after being struck by a MV were >6 times more likely to be admitted to the hospital (36.0%, 28.6% to 44.2%) compared with patients not struck by a MV (5.4%, 4.3% to 6.8%). When helmet use was recorded in patients with skull fractures, most patients were not wearing helmets at the time of injury (85.7%, 74.6% to 92.5%). CONCLUSIONS: Although the national burden of fractures associated with riding bicycles in pediatric populations has steadily decreased, it remains a significant cause of injury for children. Fractures involving MV more often require hospitalization, and an alarming number of skull fractures are noted in children not wearing helmets. These data support continued efforts to promote consistent helmet use and safer riding environments around MV in all children, but especially among 10- to 15-year-old males. LEVEL OF EVIDENCE: Level III-prognostic.