Occupant responses in conventional and ABTS seats in high-speed rear sled tests

Objective: This study compared biomechanical responses of a normally seated Hybrid III dummy on conventional and all belts to seat (ABTS) seats in 40.2 km/h (25 mph) rear sled tests. It determined the difference in performance with modern (≥2000 MY) seats compared to older (<2000 MY) seats and ABTS seats.

Methods: The seats were fixed in a sled buck subjected to a 40.2 km/h (25 mph) rear sled test. The pulse was a 15 g double-peak acceleration with 150 ms duration. The 50th percentile Hybrid III was lap–shoulder belted in the FMVSS 208 design position. The testing included 11 <2000 MY, 8 ≥2000 MY, and 7 ABTS seats. The dummy was fully instrumented, including head accelerations, upper and lower neck 6-axis load cells, chest acceleration, thoracic and lumbar spine load cells, and pelvis accelerations. The peak responses were normalized by injury assessment reference values (IARVs) to assess injury risks. Statistical analysis was conducted using Student's t test. High-speed video documented occupant kinematics.

Results: Biomechanical responses were lower with modern (≥2000 MY) seats than older (<2000 MY) designs. The lower neck extension moment was 32.5 ± 9.7% of IARV in modern seats compared to 62.8 ± 31.6% in older seats (P =.01). Overall, there was a 34% reduction in the comparable biomechanical responses with modern seats. Biomechanical responses were lower with modern seats than ABTS seats. The lower neck extension moment was 41.4 ± 7.8% with all MY ABTS seats compared to 32.5 ± 9.7% in modern seats (P =.07). Overall, the ABTS seats had 13% higher biomechanical responses than the modern seats.

Conclusions: Modern (≥2000 MY) design seats have lower biomechanical responses in 40.2 km/h rear sled tests than older (<2000 MY) designs and ABTS designs. The improved performance is consistent with an increase in seat strength combined with improved occupant kinematics through pocketing of the occupant into the seatback, higher and more forward head restraint, and other design changes. The methods and data presented here provide a basis for standardized testing of seats. However, a complete understanding of seat safety requires consideration of out-of-position (OOP) occupants in high-speed impacts and consideration of the much more common, low-speed rear impacts.     

Driver and front passenger injury in frontal crashes: Update on the effect of unbelted rear occupants

Purpose: This is a study of the influence of an unbelted rear occupant on the risk of severe injury to the front seat occupant ahead of them in frontal crashes. It provides an update to earlier studies.

Methods: 1997–2015 NASS-CDS data were used to investigate the risk for severe injury (Maximum Abbreviated Injury Score [MAIS] 4+F) to belted drivers and front passengers in frontal crashes by the presence of a belted or unbelted passenger seated directly behind them or without a rear passenger. Frontal crashes were identified with GAD1 = F without rollover (rollover ≤ 0). Front and rear outboard occupants were included without ejection (ejection = 0). Injury severity was defined by MAIS and fatality (F) by TREATMNT = 1 or INJSEV = 4. Weighted data were determined. The risk for MAIS 4+F was determined using the number of occupants with known injury status MAIS 0+F. Standard errors were determined.

Results: The risk for severe injury was 0.803 ± 0.263% for the driver with an unbelted left rear occupant and 0.100 ± 0.039% with a belted left rear occupant. The driver's risk was thus 8.01 times greater with an unbelted rear occupant than with a belted occupant (P <.001). With an unbelted right rear occupant behind the front passenger, the risk for severe injury was 0.277 ± 0.091% for the front passenger. The corresponding risk was 0.165 ± 0.075% when the right rear occupant was belted. The front passenger's risk was 1.68 times greater with an unbelted rear occupant behind them than a belted occupant (P <.001). The driver's risk for MAIS 4+F was highest when their seat was deformed forward. The risk was 9.94 times greater with an unbelted rear occupant than with a belted rear occupant when the driver's seat deformed forward. It was 13.4 ± 12.2% with an unbelted occupant behind them and 1.35 ± 0.95% with a belted occupant behind them.

Conclusions: Consistent with prior literature, seat belt use by a rear occupant significantly lowered the risk for severe injury to belted occupants seated in front of them. The reduction was greater for drivers than for front passengers. It was 87.5% for the driver and 40.6% for the front passenger. These results emphasize the need for belt reminders in all seating positions.     

Can new passenger cars reduce pedestrian lower extremity injury? A review of geometrical changes of front-end design before and after regulatory efforts

Objective: Pedestrian lower extremity represents the most frequently injured body region in car-to-pedestrian accidents. The European Directive concerning pedestrian safety was established in 2003 for evaluating pedestrian protection performance of car models. However, design changes have not been quantified since then. The goal of this study was to investigate front-end profiles of representative passenger car models and the potential influence on pedestrian lower extremity injury risk.

Methods: The front-end styling of sedans and sport utility vehicles (SUV) released from 2008 to 2011 was characterized by the geometrical parameters related to pedestrian safety and compared to representative car models before 2003. The influence of geometrical design change on the resultant risk of injury to pedestrian lower extremity—that is, knee ligament rupture and long bone fracture—was estimated by a previously developed assessment tool assuming identical structural stiffness. Based on response surface generated from simulation results of a human body model (HBM), the tool provided kinematic and kinetic responses of pedestrian lower extremity resulted from a given car's front-end design.

Results: Newer passenger cars exhibited a “flatter” front-end design. The median value of the sedan models provided 87.5 mm less bottom depth, and the SUV models exhibited 94.7 mm less bottom depth. In the lateral impact configuration similar to that in the regulatory test methods, these geometrical changes tend to reduce the injury risk of human knee ligament rupture by 36.6 and 39.6% based on computational approximation. The geometrical changes did not significantly influence the long bone fracture risk.

Conclusions: The present study reviewed the geometrical changes in car front-ends along with regulatory concerns regarding pedestrian safety. A preliminary quantitative benefit of the lower extremity injury reduction was estimated based on these geometrical features. Further investigation is recommended on the structural changes and inclusion of more accident scenarios.     

Predictors of restraint use among child occupants

Objectives: The objective of this study was to identify factors that predict restraint use and optimal restraint use among children aged 0 to 13 years.

Methods: The data set is a national sample of police-reported crashes for years 2010–2014 in which type of child restraint is recorded. The data set was supplemented with demographic census data linked by driver ZIP code, as well as a score for the state child restraint law during the year of the crash relative to best practice recommendations for protecting child occupants. Analysis used linear regression techniques.

Results: The main predictor of unrestrained child occupants was the presence of an unrestrained driver. Among restrained children, children had 1.66 (95% confidence interval, 1.27, 2.17) times higher odds of using the recommended type of restraint system if the state law at the time of the crash included requirements based on best practice recommendations.

Conclusions: Children are more likely to ride in the recommended type of child restraint when their state's child restraint law includes wording that follows best practice recommendations for child occupant protection. However, state child restraint law requirements do not influence when caregivers fail to use an occupant restraint for their child passengers.     

Effect of posture on forces and moments measured in a Hybrid III ATD lower leg

Objective: Anthropomorphic test devices (ATDs) are used to assess real injury risk to occupants of vehicles during injurious events. In the lower leg, values from load cells are compared to injury criteria developed in cadaveric studies. These criteria are typically developed with the leg in a neutral posture, whereas the ATD may assume a wide range of postures during safety evaluation tests. The degree to which the initial posture of an ATD has an effect on the measured forces and moments in the lower leg is unknown.

Methods: A Hybrid III ATD lower leg was impacted in a range of postures under conditions representing a crash test, and peak axial force and adjusted tibia index injury measures were evaluated. Ankle posture was varied in 5° increments using a custom-made footplate, and dorsi/plantarflexion (20° DF to 20° PF) and in/eversion (20° IV to 5° EV) were evaluated. Tibia angle was also varied (representing knee flexion/extension) by ±10° from neutral.

Results: Peak axial force was not affected by ankle flexion or tibia angulation. Adjusted tibia index was lowest for plantarflexion, as well as for tibia angles representative of knee extension. Both peak axial force and adjusted tibia index were lowest for postures of great inversion and were highest in neutral or near-neutral postures.

Conclusions: The range of postures tested herein spanned published injury criteria and thus would have made the difference between pass and fail in a safety evaluation. In/eversion had the largest influence on injury metrics, likely due to the change in axial stiffness and altered impact durations in these postures. Results suggest increased injury risk at neutral or near-neutral postures, whereas previous cadaveric studies have suggested that in/eversion does not influence injury risk. It is unclear whether the ATD appropriately represents the natural lower leg for impacts in out-of-position testing. Great care must be taken when initially positioning ATDs for safety evaluations, because small perturbations in posture were shown herein to have large effects on the measured injury risk using this tool.     

A new method to assess the deformations of internal organs of the abdomen during impact

Objectives: Due to limitations of classic imaging approaches, the internal response of abdominal organs is difficult to observe during an impact. Within the context of impact biomechanics for the protection of the occupant of transports, this could be an issue for human model validation and injury prediction.

Methods: In the current study, a previously developed technique (ultrafast ultrasound imaging) was used as the basis to develop a protocol to observe the internal response of abdominal organs in situ at high imaging rates. The protocol was applied to 3 postmortem human surrogates to observe the liver and the colon during impacts delivered to the abdomen.

Results: The results show the sensitivity of the liver motion to the impact location. Compression of the colon was also quantified and compared to the abdominal compression.

Conclusions: These results illustrate the feasibility of the approach. Further tests and comparisons with simulations are under preparation.     

Rating child passenger safety laws relative to best practice recommendations for occupant protection

Background: State laws regarding child passenger protection vary substantially.

Objectives: The objective of this study was to develop a scoring system to rate child passenger safety laws relative to best practice recommendations for each age of child.

Methods: State child passenger safety and seat belt laws were retrieved from the LexisNexis database for the years 2002–2015. Text of the laws was reviewed and compared to current best practice recommendations for child occupant protection for each age of child.

Results: A 0–4 scale was developed to rate the strength of the state law relative to current best practice recommendations. A rating of 3 corresponds to a law that requires a restraint that is sufficient to meet best practice, and a rating of 4 is given to a law that specifies several options that would meet best practice. Scores of 0, 1, or 2 are given to laws requiring less than best practice to different degrees. The same scale is used for each age of child despite different restraint recommendations for each age. Legislation that receives a score of 3 requires rear-facing child restraints for children under age 2, forward-facing harnessed child restraints for children aged 2 to 4, booster seats for children 5 to 10, and primary enforcement of seat belt use in all positions for children aged 11–13. Legislation requiring use of a “child restraint system according to instructions” would receive a score of 1 for children under age 2 and a 2 for children aged 2–4 because it would allow premature use of a booster for children weighing more than 13.6 kg (30 lb).

Conclusions: The scoring system developed in this study can be used in mathematical models to predict how child passenger safety legislation affects child restraint practices.     

Cross-correlation between the controlled collision environment and real-world motor vehicle collisions: Evaluating the protection of the thoracic side airbag

Objective: Thoracic side airbags (tSABs) were integrated into the vehicle fleet to attenuate and distribute forces on the occupant's chest and abdomen, dissipate the impact energy, and move the occupant away from the intruding structure, all of which reduce the risk of injury. This research piece investigates and evaluates the safety performance of the airbag unit by cross-correlating data from a controlled collision environment with field data.

Method: We focus exclusively on vehicle–vehicle lateral impacts from the NHTSA's Vehicle Crash Test Database and NASS-CDS database, which are replicated in the controlled environment by the (crabbed) barrier impact. Similar collisions with and without seat-embedded tSABs are matched to each other and the injury risks are compared.

Results: Results indicated that dummy-based thoracic injury metrics were significantly lower with tSAB exposure (P <.001). Yet, when the controlled collision environment data were cross-correlated with NASS-CDS collisions, deployment of the tSAB indicated no association with thoracic injury (tho. MAIS 2+ unadjusted relative risk [RR] = 1.14; 90% confidence interval [CI], 0.80–1.62; tho. MAIS 3+ unadjusted RR = 1.12; 90% CI, 0.76–1.65).

Conclusion: The data from the controlled collision environment indicated an unequivocal benefit provided by the thoracic side airbag for the crash dummy; however, the real-world collisions demonstrate that no benefit is provided to the occupant. This has resulted from a noncorrelation between the crash test/dummy-based design taking the abstracting process too far to represent the real-world collision scenario.     

The influence of lower extremity postures on kinematics and injuries of cyclists in vehicle side collisions

Objective: A cyclist assumes various cyclic postures of the lower extremities while pushing the pedals in a rotary motion while pedaling. In order to protect cyclists in collisions, it is necessary to understand what influence these postures have on the global kinematics and injuries of the cyclist.

Method: Finite element (FE) analyses using models of a cyclist, bicycle, and car were conducted. In the simulations, the Total Human Model of Safety (THUMS) occupant model was employed as a cyclist, and the simulation was set up such that the cyclist was hit from its side by a car. Three representative postures of the lower extremities of the cyclist were examined, and the kinematics and injury risk of the cyclist were compared to those obtained by a pedestrian FE model. The risk of a lower extremity injury was assessed based on the knee shear displacement and the tibia bending moment.

Results: When the knee position of the cyclist was higher than the hood leading edge, the hood leading edge contacted the leg of the cyclist, and the pelvis slid over the hood top and the wrap-around distance (WAD) of the cyclist's head was large. The knee was shear loaded by the hood leading edge, and the anterior cruciate ligament (ACL) ruptured. The tibia bending moment was less than the injury threshold. When the cyclist's knee position was lower than the hood leading edge, the hood leading edge contacted the thigh of the cyclist, and the cyclist rotated with the femur as the pivot point about the hood leading edge. In this case, the head impact location of the cyclist against the car was comparable to that of the pedestrian collision. The knee shear displacement and the tibia bending moment were less than the injury thresholds.

Conclusion: The knee height of the cyclist relative to the hood leading edge affected the global kinematics and the head impact location against the car. The loading mode of the lower extremities was also dependent on the initial positions of the lower extremities relative to the car structures. In the foot up and front posture, the knee was loaded in a lateral shear direction by the hood leading edge and as a result the ACL ruptured. The bicycle frame and the struck-side lower extremity interacted and could influence the loadings on lower extremities.     

Survey regarding the 0.05 blood alcohol concentration limit for driving in the United States

Background: On May 14, 2013, the National Transportation Safety Board (NTSB) proposed that states lower the blood alcohol concentration (BAC) illegal limit from 0.08 to 0.05 g/dL (also referred to as the 0.08 law and the 0.05 limit, respectively). In March 2017, this recommendation was signed into law in the State of Utah.

Objective: The objective of this survey is to investigate perceptions regarding enforcement of the 0.05 g/dL BAC limit.

Method: Opinions of law enforcement officers, prosecutors, and defense attorneys were obtained through a series of questionnaires and focus groups.

Results: Survey data were collected from 32 law enforcement officers, 20 prosecutors, and 4 defense attorneys. The participants rated the usefulness of the NHTSA's driving while intoxicated (DWI) driving cues lower for the 0.05 limit than for the 0.08 law. Some of the participants believed that training would be needed in regard to sobriety testing under the 0.05 limit. Participants also stated that adequately preparing for prosecution of drunk drivers would be more difficult under the 0.05 limit. In addition, it was believed that drunk driving cases are more likely to be withdrawn and fewer plea agreements and guilty pleas are likely under the 0.05 limit. Prosecutors were concerned that the 0.05 limit would result in poorly investigated cases and overburden the court system. Defense attorneys were concerned about the social and economic costs of a 0.05 limit.

Discussion: Overall, it appears that the 0.05 limit is viewed as enforceable and it will save lives; however, the usefulness of the NHTSA DWI Detection Guide and of the standardized field sobriety tests need to be established for lower BACs, and efforts must be made to educate people regarding the relationship between BAC and impairment and impairment and driving with the risk of injury and death.

Conclusion: Though the 0.05 limit offers promise in saving lives, the following issues associated with changing the limit to 0.05 need to be resolved prior to implementation: Validating the sobriety tests for the 0.05 limit; if needed, modifying the sobriety tests to make them effective and valid at the 0.05 limit; and training law enforcement personnel and educating the public regarding the 0.05 limit.     

Emergency braking is affected by the use of cruise control

Objective: We compared the differences in the braking response to vehicle collision between an active human emergency braking (control condition) and cruise control (CC) or adaptive cruise control (ACC).

Methods: In 11 male subjects, age 22 to 67 years, we measured the active emergency braking response during manual driving using the accelerator pedal (control condition) or in condition mimicking CC or ACC. In both conditions, we measured the brake reaction time (BRT), delay to produce the peak braking force (PBD), total emergency braking response (BRT + PBD), and peak braking force (PBF). Electromyograms of leg and thigh muscles were recorded during braking. The tonic vibratory response (TVR), Hoffman reflex (HR), and M-waves were recorded in leg muscles to explore the change in sensorimotor control.

Results: No difference in PBF, TVR amplitude, HR latency, and H_max/M_max ratio were found between the control and CC/ACC conditions. On the other hand, BRT and PBD were significantly lengthened in the CC/ACC condition (240 ± 13 ms and 704 ± 70 ms, respectively) compared to control (183 ± 7 ms and 568 ± 36 ms, respectively). BRT increased with the age of participants and the driving experience shortened PBD and increased PBF.

Conclusions: In male subjects, driving in a CC/ACC condition significantly delays the active emergency braking response to vehicle collision. This could result from higher amplitude of leg motion in the CC/ACC condition and/or by the age-related changes in motor control. Car and truck drivers must take account of the significant increase in the braking distance in a CC/ACC condition.     

Experimental investigation of the effect of occupant characteristics on contemporary seat belt payout behavior in frontal impacts

Objective: The goal of this study was to investigate the influence of the occupant characteristics on seat belt force vs. payout behavior based on experiment data from different configurations in frontal impacts.

Methods: The data set reviewed consists of 58 frontal sled tests using several anthropomorphic test devices (ATDs) and postmortem human subjects (PMHS), restrained by different belt systems (standard belt, SB; force-limiting belt, FLB) at 2 impact severities (48 and 29 km/h). The seat belt behavior was characterized in terms of the shoulder belt force vs. belt payout behavior. A univariate linear regression was used to assess the factor significance of the occupant body mass or stature on the peak tension force and gross belt payout.

Results: With the SB, the seat belt behavior obtained by the ATDs exhibited similar force slopes regardless of the occupant size and impact severities, whereas those obtained by the PMHS were varied. Under the 48 km/h impact, the peak tension force and gross belt payout obtained by ATDs was highly correlated to the occupant stature (P =.03, P =.02) and body mass (P =.05, P =.04), though no statistical difference with the stature or body mass were noticed for the PMHS (peak force: P =.09, P =.42; gross payout: P =.40, P =.48). With the FLB under the 48 km/h impact, highly linear relationships were noticed between the occupant body mass and the peak tension force (R² = 0.9782) and between the gross payout and stature (R² = 0.9232) regardless of the occupant types.

Conclusions: The analysis indicated that the PMHS characteristics showed a significant influence on the belt response, whereas the belt response obtained with the ATDs was more reproducible. The potential cause included the occupant anthropometry, body mass distribution, and relative motion among body segments specific to the population variance. This study provided a primary data source to understand the biomechanical interaction of the occupant with the restraint system. Further research is necessary to consider these effects in the computational studies and optimized design of the restraint system in a more realistic manner.     

Epidemiology and patterns of facial fractures due to road traffic accidents in Taiwan: A 15-year retrospective study

Objective: The facial region is a commonly fractured site, but the etiology varies widely by country and geographic region. To date, there are no population-based studies of facial fractures in Taiwan.

Methods: We conducted a retrospective study of patients diagnosed with facial fracture and registered in the National Health Insurance Research Database of Taiwan between 1997 and 2011. The epidemiological characteristics of this cohort were analyzed, including the etiology, fracture site, associated injuries, and sex and age distributions.

Results: A total of 6,013 cases were identified that involved facial fractures. Most patients were male (69.8%), aged 18–29 years (35.8%), and had fractures caused by road traffic accidents (RTAs; 55.2%), particularly motorcycle accidents (31.5%). Falls increased in frequency with advancing age, reaching 23.9% among the elderly (age > 65 years). The most common sites of involvement were the malar and maxillary bones (54.0%), but nasal bone fractures were more common among those younger than 18 years.

Conclusion: Most facial injuries in Taiwan occur in young males and typically result from RTAs, particularly involving motorcycles. However, with increasing age, there is an increase in the proportion of facial injuries due to falls.     

Differences in the kinematics of booster-seated pediatric occupants using two different car seats

Objective: The objective of this article is to compare the performance of forward-facing child restraint systems (CRS) mounted on 2 different seats.

Methods: Two different anthropomorphic test device (ATD) sizes (P3 and P6), using the same child restraint system (a non-ISOFIX high-back booster seat), were exposed to the ECE R44 regulatory deceleration pulse in a deceleration sled. Two different seats (seat A, seat B) were used. Three repetitions per ATD and mounting seat were done, resulting in a total of 12 sled crashes. Dummy sensors measured the head tri-axial acceleration and angular rate and the thorax tri-axial acceleration, all acquired at 10,000 Hz. A high-speed video camera recorded the impact at 1,000 frames per second. The 3D kinematics of the head and torso of the ATDs were captured using a high-speed motion capture system (1,000 Hz). A pair-matched statistical analysis compared the outcomes of the tests using the 2 different seats.

Results: Statistically significant differences in the kinematic response of the ATDs associated with the type of seat were observed. The maximum 3 ms peak of the resultant head acceleration was higher on seat A for the P3 dummy (54.5 ± 1.9 g vs. 44.2 ± 0.5 g; P =.012) and for the P6 dummy (56.0 ± 0.8 g vs. 51.7 ± 1.2 g; P =.015). The peak belt force was higher on seat A than on seat B for the P3 dummy (5,488.0 ± 198.0 N vs. 4,160.6 ± 63.6 N; P =.008) and for the P6 dummy (7,014.0 ± 271.0 N vs. 5,719.3 ± 37.4 N; P =.015). The trajectory of the ATD head was different between the 2 seats in the sagittal, transverse, and frontal planes.

Conclusion: The results suggest that the overall response of the booster-seated occupant exposed to the same impact conditions was different depending on the seat used regardless of the size of the ATD. The differences observed in the response of the occupants between the 2 seats can be attributed to the differences in cushion stiffness, seat pan geometry, and belt geometry. However, these results were obtained for 2 particular seat models and a specific CRS and therefore cannot be directly extrapolated to the generality of vehicle seats and CRS.     

Study of chest injuries to 3-year-old child occupants seated in impact shield and 5-point harness CRSs

Objective: The objective of this study was to investigate whether the 5-point harness or the impact shield child restraint system (CRS) or both have the potential to cause chest injuries to children. This is determined by examining whether the loading to the chest reaches the internal organ injury threshold for children.

Method: The chest injury risk to a child occupant in a CRS was investigated using Q3 dummy tests, finite element (FE) simulations (Q3 dummy and human models), and animal tests. The investigation was done for 2 types of CRSs (i.e., the impact shield CRS and 5-point harness CRS) based on the UN R44 dynamic test specifications.

Results: The tests using a Q3 dummy indicated that although the chest deflection of the dummy in the impact shield CRS was large, it was less than the injury threshold (40 mm). Computational biomechanics simulations (using finite element FE analysis) showed that the Q3 dummy's chest is loaded by the shield and deforms substantially under this load. To clarify whether chest injuries due to chest compression can occur with an impact shield or with the 5-point harness CRS, 7 experiments were performed using Tibetan miniature pigs with weights ranging from 9.7 to 13 kg. Severe chest and abdominal injuries (lung contusion, coronary artery laceration, liver laceration) were found in the tests using the impact shield CRS. No chest injuries were present when using the 5-point harness CRS.

Conclusion: When using the impact shield CRS, the chest deformed substantially in dummy tests and FE simulations, and chest and abdominal injuries were observed in pig tests. It is possible that these chest injuries could also occur to child occupants sitting in the impact shield CRS.     

Comparison of recidivism rates for a teenage trauma prevention program after the addition of high-fidelity patient simulation

Objectives: We evaluated the benefits of adding high-fidelity simulation to a teenage trauma prevention program to decrease recidivism rates and encourage teens to discuss actionable steps toward safe driving.

Methods: A simulated pediatric trauma scenario was integrated into an established trauma prevention program. Participants were recruited because they were court-ordered to attend this program after misdemeanor convictions for moving violations. The teenage participants viewed this simulation from the emergency medical services (EMS) handoff to complete trauma care. Participants completed a postsimulation knowledge assessment and care evaluation, which included narrative data about the experience. Qualitative analysis of color-coded responses identified common themes and experiences in participants' answers. Court records were reviewed 6 years after course completion to determine short- and long-term recidivism rates, which were then compared to our program's historical rate.

Results: One hundred twenty-four students aged 16–20 years participated over a 2-year study period. Narrative responses included general reflection, impressions, and thoughts about what they might change as a result of the course. Participants reported that they would decrease speed (30%), wear seat belts (15%), decrease cell phone use (11%), and increase caution (28%). The recidivism rate was 55% within 6 years. At 6 months it was 8.4%, at 1 year it was 20%, and it increased approximately 5–8% per year after the first year. Compared with our programs, for historical 6-month and 2-year recidivism rates, no significant difference was seen with or without simulation.

Conclusions: Adding simulation is well received by participants and leads to positive reflections regarding changes in risk-taking behaviors but resulted in no changes to the high recidivism rates This may be due to the often ineffectiveness of fear appeals.     

The psychological impact of traffic injuries sustained in a road crash by bicyclists: A prospective study

Objective: The objective of this study was to investigate the psychological impact of traffic injuries in bicyclists (cyclists) in comparison to car occupants who also sustained traffic injuries. Factors predictive of elevated psychological distress were also investigated.

Methods: An inception cohort prospective design was used. Participants included cyclists aged ≥17 years (mean age 41.7 years) who sustained a physical injury (n = 238) assessed within 28 days of the crash, following medical examination by a registered health care practitioner. Injury included musculoskeletal and soft tissue injuries and minor/moderate traumatic brain injury (TBI), excluding severe TBI, spinal cord injury, and severe multiple fractures. Assessment also occurred 6 months postinjury. Telephone-administered interviews assessed a suite of measures including sociodemographic, preinjury health and injury factors. Psychological impact was measured by pain catastrophization, trauma-related distress, and general psychological distress. The psychological health of the cyclists was compared to that of the car occupants (n = 234; mean age 43.1 years). A mixed model repeated measures analysis, adjusted for confounding factors, was used to determine differences between groups and regression analyses were used to determine contributors to psychological health in the cyclists 6 months postinjury.

Results: Cyclists had significantly better psychological health (e.g., lower pain catastrophizing, lower rates of probable posttraumatic stress disorder [PTSD], and lower general distress levels) compared to car occupants at baseline and 6 months postinjury. Factors predictive of cyclists' psychological distress included younger age, greater perceived danger of death, poorer preinjury health, and greater amount of time in hospital after the injury.

Conclusions: These data provide insight into how cyclists perceive and adjust to their traffic injuries compared to drivers and passengers who sustain traffic injuries, as well as direction for preventing the development of severe psychological injury. Future research should examine the utility of predictors of psychological health to improve recovery.     

Prevalence of drink-driving among adults in China: A nationally representative survey in 2010

Objective: We examined the prevalence of and characteristics associated with drink-driving in China. We compared this study's drink-driving findings with those from the United States to explore how effective traffic safety interventions from Western cultures might be adapted for use in China.

Methods: Data from the 2010 China Chronic Disease and Risk Factor Survey were analyzed to describe the prevalence and characteristics associated with drink-driving in China.

Results: Overall, 1.5% of Chinese adults reported drink-driving in the past 30 days—3% of males and 0.1% of females. However, among males who had driven a vehicle in the past 30 days and consumed at least one alcoholic beverage in the past 30 days, 19% reported drink-driving during the 30-day period. Excessive drinking, binge drinking, nonuse of seat belts, and having been injured in a road traffic crash in the past year were most strongly associated with drink-driving among males.

Conclusions: Drink-driving is prevalent among male drivers in China. Although large differences exist between China and the United States in the proportion of adults who drive, the proportion who consume alcohol, and some of the personal characteristics of those who drink and drive, similarities between the 2 countries are present in patterns of risk behaviors among drink-driving. To reduce injuries and deaths from drink-driving, effective interventions from Western cultures need to be tailored for adoption in China.     

Efficacy of seat-mounted thoracic side airbags in the German vehicle fleet

Objective: Thoracic side airbags (tSABs) deploy within close proximity to the occupant. Their primary purpose is to provide a protective cushion between the occupant and the intruding door. To date, various field studies investigating their injury mitigation has been limited and contradicting. The research develops efficacy estimations associated for seat-mounted tSABs in their ability to mitigate injury risk from the German collision environment.

Methods: A matched cohort study using German In-Depth Accident Study (GIDAS) data was implemented and aims to investigate the efficacy of seat-mounted tSAB units in preventing thoracic injury. Inclusion in the study required a nearside occupant involved in a lateral collision where the target vehicle exhibited a design year succeeding 1990. Collisions whereby a tSAB deployed were matched on a 1:n basis to collisions of similar severity where no airbag was available in the target vehicle. The outcome of interest was an incurred bodily or thoracic regional injury. Through conditional logistic regression, an estimated efficacy value for the deployed tSAB was determined.

Results: A total of 255 collisions with the deployed tSAB matched with 414 collisions where no tSAB was present. For the given sample, results indicated that the deployed tSAB was not able to provide an unequivocal benefit to the occupant thoracic region, because individuals exposed to the deployed tSAB were at equal risk of injury (Thorax Maximum Abbreviated Injury Scale (Tho.MAIS)2+ odds ratio [OR] = 1.04, 95% confidence interval [CI], 0.41–2.62; Tho.MAIS3+ OR = 1.15, 95% CI, 0.41–3.18). When attempting to isolate an effect for skeletal injuries, a similar result was obtained. Yet, when the tSAB was coupled with a head curtain airbag, a protective effect became apparent, most noticeable for head/face/neck (HFN) injuries (OR = 0.59, 95% CI, 0.21–1.65).

Conclusion: The reduction in occupant HFN injury risk associated with the coupled tSAB and curtain airbag may be attributable to its ability to provide coverage over previous mechanisms of injury. Yet, the sole presence of the tSAB showed no ability to provide additional benefit for the occupant's thoracic region. Future work should identify mechanisms of injury in tSAB cases and attempt to quantify improvements in the vehicle's ability to resist intrusion.