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Older adults aged 70 and older who drive have higher crash death rates per mile driven compared to middle aged (35-54 years) adults who drive in the US. Prior studies have found that depression and or antidepressant medication use in older adults are associated with an increase in the vehicular crash rate. Using data from the prospective multi-site AAA Longitudinal Research on Aging Drivers Study, this analysis examined the independent and interdependent associations of self-reported depression and antidepressant use with driving behaviors that can increase motor vehicle crash risk such as hard braking, speeding, and night-time driving in adults over age 65. Of the 2951 participants, 6.4% reported having depression and 21.9% were on an antidepressant medication. Correcting for age, race, gender, and education level, participants on an antidepressant had increased hard braking events (1.22 [1.10-1.34]) but self-reported depression alone was not associated with changes in driving behaviors.

BACKGROUND: Dietary supplement (DS) use is common and increasing among older adults, though much data available on use frequencies are from surveys and performed cross-sectionally. This paper sought to assess the frequency and pattern of dietary supplement use among older adults over time. METHODS: A secondary analysis of data from the AAA LongROAD study, a longitudinal prospective cohort study of older adult drivers, using data from baseline and the first two years of follow up included a total of 2990 drivers aged 65-79 years recruited at five study sites across the US from July 2015 to March 2017. Participants underwent baseline and annual evaluations, which included a brown bag medication review. DS were identified and categorized according to type and key components. Prevalence and pattern of DS use over time and relationship to demographics were measured with frequency and Chi squared analyses. RESULTS: 84% of participants took at least one dietary supplement during the 2-year study period, and 55% of participants continually reported use. DS accounted for approximately 30% of the total pharmacologic-pill burden in all years. Participants who were White non-Hispanic, female, 75-79 years of age at baseline, and on more non-supplement medications took significantly more dietary supplements (P

INTRODUCTION: Frailty and low physical performance are modifiable factors and, therefore, targets for interventions aimed at delaying driving cessation (DC). The objective was to determine the impact of frailty and physical performance on DC. METHODS: Multisite prospective cohort of older drivers. The key inclusion criteria are as follows: active driver age 65-79 years, possessing a valid drivers license, without significant cognitive impairment, and driving a 1996 car or a newer model car. Of the 2,990 enrolled participants, 2,986 (99.9%) had at least one frailty or Short Physical Performance Battery (SPPB) measure and were included in this study. In total, 42% of participants were aged 65-69 years, 86% were non-Hispanic white, 53% were female, 63% were married, and 41% had a high degree of education. The Fried Frailty Phenotype and the Expanded Short Physical Performance Battery (SPPB) from the National Health and Aging Trends Study were utilized. At each annual visit, DC was assessed by the participant notifying the study team or self-reporting after no driving activity for at least 30 days, verified via GPS. Cox proportional hazard models, including time-varying covariates, were used to examine the impact of the SPPB and frailty scores on time to DC. This assessment included examining interactions by sex. RESULTS: Seventy-three participants (2.4%) stopped driving by the end of year 5. Among women with a fair SPPB score, the adjusted hazard ratio (HR) of DC was 0.26 (95% confidence interval (CI) 0.10-0.65) compared to those with a poor SPPB score. For those with a good SPPB score, the adjusted HR of DC had a p-value of

OBJECTIVE: Falls in older adults are associated with increased motor vehicle crash risk, possibly mediated by driving behavior. We examined the relationship of falls and fear of falling (FOF) with subsequent objectively measured driving habits. METHODS: This multi-site, prospective cohort study enrolled 2990 active drivers aged 65-79 (53% female). At enrollment, we assessed falls in the past year and FOF (Short Falls Efficacy Scale-International). Driving outcomes included exposure, avoidance of difficult conditions, and unsafe driving during one-year follow-up, using in-vehicle Global Positioning System devices. RESULTS: Past-year falls were associated with more hard braking events (HBE). High FOF was associated with driving fewer days, miles, and trips, driving nearer home and more HBE. Differences were attenuated and not significant after accounting for health, function, medications and sociodemographics. DISCUSSION: Differences in objectively measured driving habits according to past-year fall history and FOF were largely accounted for by differences in health and medications. Rather than directly affecting driving, falls and FOF may serve as markers for crash risk and reduced community mobility due to age-related changes and poor health.

Humans have outsized effects on ecosystems, in part by initiating trophic cascades that impact all levels of the food chain.1,2 Theory suggests that disease outbreaks can reverse these impacts by modifying human behavior,3,4 but this has not yet been tested. The COVID-19 pandemic provided a natural experiment to test whether a virus could subordinate humans to an intermediate link in the trophic chain, releasing a top carnivore from a landscape of fear. Shelter-in-place orders in the Bay Area of California led to a 50% decline in human mobility, which resulted in a relaxation of mountain lion aversion to urban areas. Rapid changes in human mobility thus appear to act quickly on food web functions, suggesting an important pathway by which emerging infectious diseases will impact not only human health but ecosystems as well.

Visual crowding-the deleterious influence of nearby objects on object recognition-is considered to be a major bottleneck for object recognition in cluttered environments. Although crowding has been studied for decades with static and artificial stimuli, it is still unclear how crowding operates when viewing natural dynamic scenes in real-life situations. For example, driving is a frequent and potentially fatal real-life situation where crowding may play a critical role. In order to investigate the role of crowding in this kind of situation, we presented observers with naturalistic driving videos and recorded their eye movements while they performed a simulated driving task. We found that the saccade localization on pedestrians was impacted by visual clutter, in a manner consistent with the diagnostic criteria of crowding (Bouma's rule of thumb, flanker similarity tuning, and the radial-tangential anisotropy). In order to further confirm that altered saccadic localization is a behavioral consequence of crowding, we also showed that crowding occurs in the recognition of cluttered pedestrians in a more conventional crowding paradigm. We asked participants to discriminate the gender of pedestrians in static video frames and found that the altered saccadic localization correlated with the degree of crowding of the saccade targets. Taken together, our results provide strong evidence that crowding impacts both recognition and goal-directed actions in natural driving situations.

The biological, environmental, and psychosocial changes that occur in adolescence engender an increase in risk taking often linked to the high rates of motor vehicle crashes amongst young drivers. Most U.S. adolescents suffer from poor sleep, which is known to exacerbate the risk of driving crashes; however, research has yet to uncover a neurobiological link between sleep and risky driving in adolescence. Here, we examined potential moderators of the sleep-risk relation in fifty-six adolescents (14-18y/o) as they completed a driving task during fMRI. While poor sleep was associated with increased risky driving (i.e., running more yellow lights), good sleep emerged as a novel buffer against risky driving in lower sensation-seeking adolescents. Neural activity in the ventral striatum (VS), a key node of the risk-taking circuit, also moderated the sleep-risk association: sleep was related to risk-taking in individuals demonstrating high, but not low, VS response during risky decision-making, suggesting that reward-related neural response may underly the connection between sleep and risk-taking in adolescence. This study sheds light on the risk of driving crashes in youth by highlighting sleep as both an exacerbator and a buffer of risky driving in adolescence. Taken together, these results underscore the importance of improving adolescent sleep.

Risk-taking behavior can result in a range of maladaptive behaviors such as illicit substance use, unsafe driving, and high-risk sexual behavior. Perception of risk and preference for engaging in risky behaviors have been measured using both self-report measures and a range of behavioral tasks designed for the purpose, and these may predict future risk-taking behavior. However, the interrelationships between these measures and the latent constructs underlying them are poorly understood. In the present study, we examined data from over 1,000 men and women who completed measures of risk-related behaviors, including self-reports of perception of risk, propensity to engage in risky behaviors, and incentivized performance on tasks that involve risk. We conducted principal component analyses (PCAs) to understand the underlying latent structure of these measures. A PCA with the full sample revealed 5 distinct components, corresponding to measures of (a) health/ethical risks, (b) discounting of uncertain rewards, (c) risk of personal finances, (d) preferences in recreational hobbies and social interactions that involve risk, and (e) behavior involving risks in interpersonal interactions. Although we found sex differences on several of the measures, the sex-adjusted PCA components were similar to those of the unadjusted full sample PCA. These findings add to a growing literature revealing different components of the broad category of risk perception and risk-taking behaviors. A better understanding of the multidimensionality of risk preference will help lay the foundation for more refined measures, develop better predictors of future risk-taking behavior, and ultimately to study the genetic or other biological basis of risk-taking. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

Risk-taking behavior can result in a range of maladaptive behaviors such as illicit substance use, unsafe driving, and high-risk sexual behavior. Perception of risk and preference for engaging in risky behaviors have been measured using both self-report measures and a range of behavioral tasks designed for the purpose, and these may predict future risk-taking behavior. However, the interrelationships between these measures and the latent constructs underlying them are poorly understood. In the present study, we examined data from over 1,000 men and women who completed measures of risk-related behaviors, including self-reports of perception of risk, propensity to engage in risky behaviors, and incentivized performance on tasks that involve risk. We conducted principal component analyses (PCAs) to understand the underlying latent structure of these measures. A PCA with the full sample revealed 5 distinct components, corresponding to measures of (a) health/ethical risks, (b) discounting of uncertain rewards, (c) risk of personal finances, (d) preferences in recreational hobbies and social interactions that involve risk, and (e) behavior involving risks in interpersonal interactions. Although we found sex differences on several of the measures, the sex-adjusted PCA components were similar to those of the unadjusted full sample PCA. These findings add to a growing literature revealing different components of the broad category of risk perception and risk-taking behaviors. A better understanding of the multidimensionality of risk preference will help lay the foundation for more refined measures, develop better predictors of future risk-taking behavior, and ultimately to study the genetic or other biological basis of risk-taking. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

BACKGROUND AND OBJECTIVES: Balancing both driver mobility and safety is important for the well-being of older adults. However, research on the association of physical function with these 2 driving outcomes has yielded inconsistent findings. This study examined whether physical functioning of older drivers, as measured by the Short Physical Performance Battery (SPPB), is associated with either driving space or crash involvement. METHODS: Using cross-sectional data of active drivers aged 65-79 years from the AAA Longitudinal Research on Aging Drivers (LongROAD) study (n = 2,990), we used multivariate log-binomial and logistic regressions to estimate the associations of the SPPB with either self-reported restricted driving space in the prior 3 months or any crashes in the past year. Interaction with gender was assessed using likelihood ratio tests. RESULTS: After adjustment, older drivers with higher SPPB scores (higher physical functioning) had lower prevalence of restricted driving space (8-10 vs. 0-7, prevalence ratio [PR] = 0.88, 95% confidence interval [CI]: 0.78-0.99; 11-12 vs. 0-7, PR = 0.78, 95% CI: 0.61-0.99). Fair (8-10), but not good (11-12), scores were significantly associated with reduced crash involvement (8-10 vs. 0-7, odds ratio [OR] = 0.71, 95% CI: 0.60-0.84). Gender was not a significant effect modifier. DISCUSSION AND IMPLICATIONS: This study provides evidence that higher physical functioning is associated with better driving mobility and safety and that the SPPB may be useful for identifying at-risk drivers. Further research is needed to understand physical functionings longitudinal effects and the SPPBs role in older driver intervention programs.

BACKGROUND: Opioid medications are important therapeutic options to mitigate the harmful effects of pain but can also impair driving ability. We sought to explore opioid use, pain levels, and driving experiences among older drivers. METHODS: Cognitively intact drivers ages 65 to 79 years were recruited for the multisite AAA Longitudinal Research on Aging Drivers (LongROAD) study (n = 2990). This cross-sectional analysis used data from the baseline questionnaire and brown-bag medication review. RESULTS: Among LongROAD participants (47% male, 88% white, 41% aged 65 to 69 years), 169 (5.7%) reported currently taking an opioid, with a median daily dose of 20 morphine milligram equivalents. Participants did not differ significantly in opioid use by age, gender, race, or ethnicity (P > .05). After adjustment for age, gender, race and ethnicity, participants who were taking opioids (vs not) were significantly more likely to report self-regulated driving reduction and reduced driving ability. However, these effects became nonsignificant when hospitalization, impaired physical function and other factors associated with opioid use were controlled. CONCLUSIONS: In this study from a large, geographically diverse sample of older adults, there was an association between opioid use and several self-reported measures of driving behavior and ability. However, future work should clarify the effects on driving of opioid use from the effects of the painful medical conditions for which the opioids are being taken. Clinicians should continue to discuss the risks and benefits of opioid medications with patients, including risks related to driving safety.

Ridehailing services such as Uber have been promoted as viable interventions for curbing alcohol-involved driving fatalities. However, evidence of ridehailing's impact has been mixed, with some studies finding no association but others finding either an increase or a decrease in fatalities. We contribute to this literature by examining more recent years of data, which capture a period during which Uber ridership has grown substantially and alcohol-involved fatalities have increased. Furthermore, we test whether the relationship between Uber availability and traffic fatalities depends on local characteristics. We employ multivariate regression models to test the association between Uber availability and total, alcohol-involved, and weekend and holiday-specific traffic fatalities in the 100 most populated metropolitan areas in the United States between 2009 and 2017. We find that Uber availability is not associated with changes in total, alcohol-involved, and weekend and holiday-specific traffic fatalities in aggregate, yet it is associated with increased traffic fatalities in urban, densely populated counties.

Thailand has the highest road traffic fatality rate in Southeast Asia, making road safety a critical public health concern. A 2015 World Health Organization (WHO) Report showed that speeding behavior was the most important determinant for road traffic crashes in Thailand. Here, we aimed to examine associations of socio-demographic factors (gender, age, socioeconomic status) with self-reported motorcycle speeding behavior. Additionally, we examined a potential role of time discounting and risk preference as mediators in the association of socio-demographic factors with speeding. We used data obtained from the Mahasarakham University Social Network Survey 2018 (MSUSSS) (N = 150). We ran linear network autocorrelation models (lnam) to account for the data's social network structure. We found that males are more likely than females to engage in speeding behavior (β = 0.140, p = 0.001) and to discount the future (β = 5.175, p = 0.017). However, further causal mediation analysis showed that time discounting does not mediate the gender-speeding association (p for mediation = 0.540). Although socioeconomic status (subjective social class) was not associated with speeding (β = 0.039, p = 0.177), age was marginally associated with speeding (β = 0.005, p = 0.093). Future studies may consider using a larger sample.

This study examined cannabis use and driving outcomes among older drivers in Colorado, which has legalized medical and recreational use. The associations of self-reported past-year cannabis use with diverse driving outcomes were assessed in 598 drivers aged 65-79 (51% female, 70% with postsecondary education), using regression analysis to adjust for health and sociodemographic characteristics. Two hundred forty four (40.8%) drivers reported ever using cannabis. Fifty-four drivers (9.0%) reported past-year use, ranging from more than once a day (13.0%) to less than once a month (50.0%). Of past-year users, 9.3% reported cannabis use within 1 h of driving in the past year. Past-year users were younger, less highly educated, lower income, and reported significantly worse mental, emotional, social and cognitive health status than drivers without past-year use. Past-year users were four times as likely to report having driven when they may have been over the legal blood-alcohol limit (adjusted OR [aOR] = 4.18; 95% CI: 2.11, 8.25) but were not more likely to report having had a crash or citation (aOR = 1.36; 95% CI: 0.70, 2.66) in the past year. Users and non-users had similar scores on self-rated abilities for safe driving (adjusted beta=-0.04; 95% CI: -0.23, 0.15) and on driving-related lapses, errors and violations in the past year (adjusted beta = 0.04; 95% CI: -0.04, 0.12). Further study is needed to establish driving risks and behaviours related to cannabis use, independent of other associated risk factors, among older adults.

BACKGROUND: Potentially Inappropriate Medication (PIM) use has been studied in a variety of older adult populations across the world. We sought to examine the prevalence and correlates of PIM use in older drivers. METHODS: We applied the American Geriatrics Society 2015 Beers Criteria to baseline data collected from the brown-bag review of medications for participants of the Longitudinal Research on Aging Drivers (LongROAD) study to examine the prevalence and correlates of PIM use in a geographically diverse, community-dwelling sample of older drivers (n = 2949). Proportions of participants who used one or more PIMs according to the American Geriatrics Society 2015 Beers Criteria, and estimated odds ratios (ORs) and 95% confidence intervals (CIs) of PIM use associated with participant characteristics were calculated. RESULTS: Overall, 18.5% of the older drivers studied used one or more PIM. The most commonly used therapeutic category of PIM was benzodiazepines (accounting for 16.6% of the total PIMs identified), followed by nonbenzodiazepine hypnotics (15.2%), antidepressants (15.2%), and first-generation antihistamines (10.5%). Compared to older drivers on four or fewer medications, the adjusted ORs of PIM use were 2.43 (95% CI 1.68-3.51) for those on 5-7 medications, 4.19 (95% CI 2.95-5.93) for those on 8-11 medications, and 8.01 (95% CI 5.71-11.23) for those on ≥12 medications. Older drivers who were female, white, or living in urban areas were at significantly heightened risk of PIM use. CONCLUSION: About one in five older drivers uses PIMs. Commonly used PIMs are medications known to impair driving ability and increase crash risk. Implementation of evidence-based interventions to reduce PIM use in older drivers may confer both health and safety benefits. TRIAL REGISTRATION: Not applicable.

BACKGROUND:The use of distracting technology is an increasing source of risk for injury among trauma patients. Both drivers and pedestrians show increased unsafe behavior. The data for prevalence and risk for distraction in trauma has varied widely. Our hypothesis is that distraction is more highly prevalent and widely distributed among all mechanisms of injury and variety of trauma patients. METHODS:A 10-question survey of adult trauma victims at a Level I trauma center regarding distraction at time of event was performed, examining age, sex, ethnicity, education level, mode of injury and role in the accident (driver, passenger, pedestrian, bicyclist, motorcyclist). Multiple-variable logistic regression was performed to identify risk factors for distraction. RESULTS:From June 2016 to October 2018, 1,316 patients were surveyed, and 1,011 (76.8%) patients reported their role in the traffic accident. The prevalence of distraction was 21.73% among drivers, 9.01% among passengers, 16.50% among pedestrians, 20.00% among bicyclists, and 8.09% among motorcyclists. Males (odds ratio [OR], 1.84; 95% confidence interval [CI], 1.26-2.67) as well as all Others (OR, 2.09; 95% CI, 1.10-3.98) showed statistically significant increased risk for distraction. Motorcyclist (OR, 0.25; 95% CI, 0.13-0.50) and passenger (OR, 0.37; 95% CI, 0.18-0.77) roles during collision were a lowered risk of distraction. Furthermore, Asian/Pacific Islanders (OR, 1.62; 95% CI, 0.94-2.79) trended toward being at greater risk for distraction. CONCLUSION:Distraction is prevalent among a wide range of traffic accident victims, not just drivers. Males as well as all Others are more likely to be distracted. In contrast, motorcyclists and passengers are less likely to be distracted. Further studies to assist in determining effective interventions and public safety efforts aimed at specific at-risk groups beyond motor vehicle drivers are warranted. LEVEL OF EVIDENCE:Epidemiological, level V.

BACKGROUND: Older adult drivers may experience decreases in driving safety with age or health status change. Discussing driving safety may help them plan for driving restriction and eventual cessation. Here, we sought to examine conversations between older adults and their family members and physicians. METHODS: In this multi-site cross-sectional analysis of baseline data from the AAA Longitudinal Research on Aging Drivers (LongROAD) cohort study, we measured the prevalence and characteristics of family and physician driving discussions. We examined associations between having driving discussions and participant characteristics using multivariate logistic regression. RESULTS: Of 2990 current drivers aged 65 to 79 years (53% female, 85.5% White), only 14.2% reported discussing driving safety with family and 5.5% had discussions with physicians. Men (adjusted OR, 1.32; 95% CI, 1.05 to 1.66) and those with Masters degrees or higher (adjusted OR, 1.65; 95% CI, 1.27 to 2.13) more often had family discussions. Those with at least a Masters degree were also more likely to speak with their physician (adjusted OR, 1.77; 95% CI, 1.17 to 2.68). CONCLUSION: Few older adults had driving safety conversations with their family or physicians. Practical and effective interventions are needed to engage family and physicians in assisting older adults with risk assessment and driving cessation planning to maintain mobility and well-being.

RationaleGamma-hydroxybutyrate acid (GHB), a GABAB receptor agonist approved for treatment of narcolepsy, impairs driving ability, but little is known about doses and plasma concentrations associated with impairment and time course of recovery.ObjectiveTo assess effects of oral GHB (Xyrem®) upon driving as measured by a driving simulator, and to determine plasma concentrations associated with impairment and the time course of recovery.MethodsRandomized, double-blind, two-arm crossover study, during which 16 participants received GHB 50 mg/kg orally or placebo. GHB blood samples were collected prior to and at 1, 3, and 6 h post dosing. Driving simulator sessions occurred immediately after blood sampling.ResultsPlasma GHB was not detectable at baseline or 6 h post dosing. Median GHB concentrations at 1 and 3 h were 83.1 mg/L (range 54-110) and 24.4 mg/L (range 7.2-49.7), respectively. Compared to placebo, at 1 h post GHB dosing, significant differences were seen for the life-threatening outcome collisions (p

Emergency contraceptive pills (ECP) were recently made available over the counter in Bhutan. We evaluated knowledge, attitudes, and practices concerning ECP in 2 populations at risk for HIV and STI (sexually transmitted infections): entertainment women (drayang) and male truck drivers and helpers (truckers). Of 179 drayang and 437 truckers intercepted at venues, 73.7 and 21.1%, respectively, had heard of ECP; 47.0% of drayang had used them. Their concerns about ECP use included harm to the body, impact on future pregnancy, side effects, and HIV/STI risk. Education programs are needed in Bhutan to increase awareness of ECP for unplanned pregnancy and condoms to prevent HIV and STI.

Given that novice drivers tend to be young, and teenagers and young adult drivers are involved in the greatest number of accidents, it is important that we understand what factors impact the driving skills of this population of drivers. The primary aim of the present study was to understand the impact of gender, organized athletics, and video gaming on driving skills of novice drivers under real-world driving conditions. Novice driving students having less than five hours driving experience previous to a normal driving lesson were evaluated on their self-confidence (self-reported) prior to the lesson and driving skill evaluated by their instructor during the course of the lesson. Information was collected about gender, age, whether or not the students were involved in organized athletics, and the extent of their video game playing. There was no impact of gender or extent of video game playing on driving skills. Females were significantly less self-confident with driving than males, but this did not translate to gender differences in driving skills. Being involved in organized athletics-either currently or in the past-significantly enhanced driving skills in both females and males. Finally, novice drivers' age was negatively correlated with driving skills. That is, younger novice drivers (especially males) had better driving skills than older novice drivers. This is counter to popular belief that young drivers lack technical driving skills because they have less experience behind the wheel. Based on the results of the current study, we hypothesize that the relatively high accident rate of younger drivers (especially male drivers) is most likely due to inattention to safety considerations rather than lack of technical driving ability.

PurposeTo examine the associations between substance use and antisocial behavior trajectories and seven risky behaviors over time.MethodData were collected from a high-risk sample of adolescents followed into young adulthood. Five trajectory classes, identified based on dual development of substance use and antisocial behavior symptoms, were used to predict three risky driving and four risky sexual behaviors.ResultsIn this high-risk sample (n=530), participants reported notably high overall rates of reckless driving (55.5%) and unprotected sex under the influence (44.8%) in the past year. Risky behaviors that are typically of low base rates in population-based studies were also elevated, with 8.8% reporting past-year driving under the influence (DUI) charge, 17.6% reporting lifetime sexually transmitted infection (STI), and 10.4% reporting lifetime injection drug use. The Dual Chronic class had the highest levels of all seven risky behaviors, and were 3-4 times more likely to report risky driving, lifetime STI, and injection drug use than the Relatively Resolved class. Rates of past-year reckless driving and DUI were elevated among classes with persistent antisocial behavior, whereas rates of DUI, DUI charge, and unprotected sex under the influence were elevated among classes with persistent substance use.ConclusionsYoung adults with persistent co-occurring substance use and antisocial behavior engage in multiple very costly risky behaviors. Differential associations between risky behaviors and trajectory classes highlight the need for targeted interventions.

BackgroundFew studies have comprehensively evaluated the effectiveness of multi-faceted interventions intended to improve pedestrian safety. "Watch for Me NC" is a multi-faceted, community-based pedestrian safety program that includes widespread media and public engagement in combination with enhanced law enforcement activities (i.e., police outreach and targeted pedestrian safety operations conducted at marked crosswalks) and low-cost engineering improvements at selected crossings. The purpose of this study was to estimate the effect of the law enforcement and engineering improvement components of the program on motor vehicle driver behavior, specifically in terms of increased driver yielding to pedestrians in marked crosswalks.MethodsThe study used a pre-post design with a control group, comparing crossing locations receiving enforcement and low-cost engineering treatments (enhanced locations) with locations that did not (standard locations) to examine changes in driver yielding over a 6-month period from 2013 to 2014. A total of 24,941 drivers were observed in 11,817 attempted crossing events at 16 crosswalks in five municipalities that were participating in the program. Observations of real pedestrians attempting to use the crosswalks ("naturalistic" crossing) were supplemented by observations of trained research staff attempting the same crossings following an established protocol ("staged" crossings). Generalized estimating equations (GEE) were used to model driver yielding rates, accounting for repeated observations at the crossing locations and controlling other factors that affect driver behavior in yielding to pedestrians in marked crosswalks.ResultsAt crossings that did not receive enhancements (targeted police operations or low-cost engineering improvements), driver yielding rates did not change from before to after the Watch for Me NC program. However, yielding rates improved significantly (between 4 and 7 percentage points on average) at the enhanced locations. This was true for both naturalistic and staged crossings.ConclusionsThis study provides evidence that enhanced enforcement and low-cost engineering improvements, as a part of a broader program involving community-based outreach, can increase driver yielding to pedestrians in marked crosswalks. These data are important for the staff and decision-makers involved in pedestrian safety programs to gain a better understanding of the different engineering and behavioral mechanisms that could be used to improve driver yielding rates.

Study objectivesTo evaluate the effect of an employer-mandated obstructive sleep apnea (OSA) program on the risk of serious preventable truck crashes.MethodsData are from the first large-scale, employer-mandated program to screen, diagnose, and monitor OSA treatment adherence in the US trucking industry. A retrospective analysis of cohorts was constructed: polysomnogram-diagnosed drivers (OSA positive n = 1,613, OSA negative n = 403) were matched to control drivers unlikely to have OSA (n = 2,016) on two factors affecting crash risk, experience-at-hire and length of job tenure; tenure was matched on the date of each diagnosed driver's polysomnogram. Auto-adjusting positive airway pressure (APAP) treatment was provided to all cases (i.e. OSA positive drivers); treatment adherence was objectively monitored. Cases were grouped by treatment adherence: "Full Adherence" (n = 682), "Partial Adherence" (n = 571), or "No Adherence" (n = 360). Preventable Department-of-Transportation-reportable crashes/100,000 miles were compared across study subgroups. Robustness was assessed.ResultsAfter the matching date, "No Adherence" cases had a preventable Department of Transportation-reportable crash rate that was fivefold greater (incidence rate ratio = 4.97, 95% confidence interval: 2.09, 10.63) than that of matched controls (0.070 versus 0.014 per 100,000 miles). The crash rate of "Full Adherence" cases was statistically similar to controls (incidence rate ratio = 1.02, 95% confidence interval: 0.48, 2.04; 0.014 per 100,000 miles).ConclusionsNontreatment-adherent OSA-positive drivers had a fivefold greater risk of serious preventable crashes, but were discharged or quit rapidly, being retained only one-third as long as other subjects. Thus, the mandated program removed risky nontreatment-adherent drivers and retained adherent drivers at the study firm. Current regulations allow nonadherent OSA cases to drive at another firm by keeping their diagnosis private.CommentaryA commentary on this article appears in this issue on page 961.

ObjectiveAlcohol-impaired (AI) driving among college students remains a significant public health concern and may be the single most risky drinking outcome among young adults. Brief motivational interventions (BMIs) have been shown to reduce alcohol use and problems, but their specific efficacy for decreasing AI driving among college students is unknown. The present study analyzed data from three randomized controlled trials of BMI (Murphy et al., 2010: n = 74; Borsari et al., 2012: n = 530; and Martens et al., 2013: n = 365) to evaluate whether BMIs are associated with reductions in AI driving among college student drinkers.MethodParticipants in all three studies were randomized to BMI or control conditions. Participants reported whether they had driven under the influence (yes/no) following the BMI over the follow-up period.ResultsSeparate binary logistic regression analyses were conducted for each study. For Studies 1 and 2, these analyses revealed that a BMI was significantly associated with reductions in AI driving at the final (6-month and 9-month, respectively) follow-up compared with the control condition. For Study 3, analyses revealed that a single-component BMI focused on the correction of misperceptions of descriptive norms was significantly associated with reductions in AI driving compared with the control group at the final (6-month) followup, whereas a single-component BMI focused on the use of protective behavioral strategies was not. Change in drinking level did not mediate the relationship between the condition and the change in AI driving.ConclusionsCounselor-administered BMIs that include descriptive normative feedback are associated with significant reductions in AI driving compared with control.

ObjectiveTo describe and compare characteristics of older adults who drive after drinking and those who do not, whether an intervention addressing at-risk drinking reduces risk among those reporting driving after drinking, and reasons reported for driving after drinking.MethodsSecondary data analysis of a randomized trial testing the efficacy of a multifaceted intervention to reduce at-risk drinking among adults with a mean age of 68 years in primary care (N = 631).ResultsAlmost a quarter of at-risk drinkers reported driving after drinking (N = 154). Compared to those who did not drive after drinking, those who did were more likely to be younger, male, and working. They consumed a higher average number of drinks per week, had more reasons they were considered at-risk drinkers, and were more likely to meet at-risk drinking criteria due to amount of drinking and binge drinking. Those driving after drinking at baseline reduced the frequency of this behavior at 3 and 12 months and there were no statistically significant differences in the proportions of persons still engaging in driving after drinking among those who were assigned to intervention or control groups. Reasons for driving after drinking included not thinking that it was a problem and having to get home.ConclusionsDriving after drinking is common in this population of older, at-risk drinkers recruited in primary care settings and, like younger adults, men and those reporting binge drinking are more likely to engage in this behavior. Given that this behavior is dangerous and the population of older adults is fast growing, interventions addressing driving after drinking are needed.

The National Highway Traffic Safety Administration (NHTSA) recently updated its 2003 and 2010 logistic regression analyses of the effect of a reduction in light-duty vehicle mass on US societal fatality risk per vehicle mile traveled (VMT; Kahane, 2012). Societal fatality risk includes the risk to both the occupants of the case vehicle as well as any crash partner or pedestrians. The current analysis is the most thorough investigation of this issue to date. This paper replicates the Kahane analysis and extends it by testing the sensitivity of his results to changes in the definition of risk, and the data and control variables used in the regression models. An assessment by Lawrence Berkeley National Laboratory (LBNL) indicates that the estimated effect of mass reduction on risk is smaller than in Kahane's previous studies, and is statistically non-significant for all but the lightest cars (Wenzel, 2012a). The estimated effects of a reduction in mass or footprint (i.e. wheelbase times track width) are small relative to other vehicle, driver, and crash variables used in the regression models. The recent historical correlation between mass and footprint is not so large to prohibit including both variables in the same regression model; excluding footprint from the model, i.e. allowing footprint to decrease with mass, increases the estimated detrimental effect of mass reduction on risk in cars and crossover utility vehicles (CUVs)/minivans, but has virtually no effect on light trucks. Analysis by footprint deciles indicates that risk does not consistently increase with reduced mass for vehicles of similar footprint. Finally, the estimated effects of mass and footprint reduction are sensitive to the measure of exposure used (fatalities per induced exposure crash, rather than per VMT), as well as other changes in the data or control variables used. It appears that the safety penalty from lower mass can be mitigated with careful vehicle design, and that manufacturers can reduce mass as a strategy to increase their vehicles' fuel economy and reduce greenhouse gas emissions without necessarily compromising societal safety.

Cognitive control is defined by a set of neural processes that allow us to interact with our complex environment in a goal-directed manner. Humans regularly challenge these control processes when attempting to simultaneously accomplish multiple goals (multitasking), generating interference as the result of fundamental information processing limitations. It is clear that multitasking behaviour has become ubiquitous in todays technologically dense world, and substantial evidence has accrued regarding multitasking difficulties and cognitive control deficits in our ageing population. Here we show that multitasking performance, as assessed with a custom-designed three-dimensional video game (NeuroRacer), exhibits a linear age-related decline from 20 to 79 years of age. By playing an adaptive version of NeuroRacer in multitasking training mode, older adults (60 to 85 years old) reduced multitasking costs compared to both an active control group and a no-contact control group, attaining levels beyond those achieved by untrained 20-year-old participants, with gains persisting for 6 months. Furthermore, age-related deficits in neural signatures of cognitive control, as measured with electroencephalography, were remediated by multitasking training (enhanced midline frontal theta power and frontal-posterior theta coherence). Critically, this training resulted in performance benefits that extended to untrained cognitive control abilities (enhanced sustained attention and working memory), with an increase in midline frontal theta power predicting the training-induced boost in sustained attention and preservation of multitasking improvement 6 months later. These findings highlight the robust plasticity of the prefrontal cognitive control system in the ageing brain, and provide the first evidence, to our knowledge, of how a custom-designed video game can be used to assess cognitive abilities across the lifespan, evaluate underlying neural mechanisms, and serve as a powerful tool for cognitive enhancement.

The National Highway Traffic Safety Administration (NHTSA) recently updated its 2003 and 2010 logistic regression analyses of the effect of a reduction in light-duty vehicle mass on US fatality risk per vehicle mile traveled (VMT). The current NHTSA analysis is the most thorough investigation of this issue to date. LBNL's assessment of the analysis indicates that the estimated effect of mass reduction on risk is smaller than in the previous studies, and statistically non-significant for all but the lightest cars. The effects three recent trends in vehicle designs and technologies have on societal fatality risk per VMT are estimated, and whether these changes might affect the relationship between vehicle mass and fatality risk in the future. Side airbags are found to reduce fatality risk in cars, but not necessarily light trucks or CUVs/minivans, struck in the side by another light-duty vehicle; reducing the number of fatalities in cars struck in the side is predicted to reduce the estimated detrimental effect of footprint reduction, but increase the detrimental effect of mass reduction, in cars on societal fatality risk. Better alignment of light truck bumpers with those of other vehicles appears to result in a statistically significant reduction in risk imposed on car occupants; however, reducing this type of fatality will likely have little impact on the estimated effect of mass or footprint reduction on risk. Finally, shifting light truck drivers into safer, car-based vehicles, such as sedans, CUVs, and minivans, would result in larger reductions in societal fatalities than expected from even substantial reductions in the masses of light trucks. A strategy of shifting drivers from truck-based to car-based vehicles would reduce fuel use and greenhouse gas emissions, while improving societal safety.

This study describes health and safety concerns and self-care strategies of San Francisco taxi drivers. Focus groups and a written cross-sectional survey were done in a convenience sample of taxi drivers working in San Francisco. Sessions were audiotaped, transcribed in English, and independently coded to identify major health and safety themes, using thematic content analysis. Strategies to manage health and safety issues are the focus of this analysis. Five focus groups were held in 2009 with 36 participants. Major health and safety themes included stress, body pain, danger, vulnerable employment status, and concerns related to unhealthy working conditions. Self-care strategies included diffusion/decompression to manage stress, maintaining a positive attitude, maintaining power and control, and practicing proactive self-care. Creative self-care strategies were described by taxi drivers to keep healthy and safe at work. These data will inform future self-care interventions to reduce health and safety risks of taxi driving.

BackgroundThe Hispanic population is one group that is involved in a disproportionately high percentage of fatal motor vehicle collisions in the United States.Study objectivesThis study investigated demographic factors contributing to a lack of knowledge and awareness of traffic laws among Hispanic drivers involved in motor vehicle collisions (MVCs) in southern California.MethodsThe cross-sectional study enrolled adults (n = 190) involved in MVCs presenting to a Level I trauma center in southern California over a 7-month period. Subjects completed a survey about California traffic law knowledge (TLK) consisting of eight multiple-choice questions. The mean number of questions answered correctly was compared between groups defined by demographic data.ResultsThe mean number of TLK questions answered correctly by Hispanic and non-Hispanic white groups were significantly different at 4.13 and 4.62, respectively (p = 0.005; 95% confidence interval -0.83 to -0.15). Scores were significantly lower in subjects who were not fluent in English, had less than a high school education, did not possess a current driver's license, and received their TLK from sources other than a driver's education class or Department of Motor Vehicle materials. Analysis of variance showed that the source of knowledge was the strongest predictor of accurate TLK.ConclusionSource of TLK is a major contributing factor to poor TLK in Hispanics. An emphasis on culturally specific traffic law education is needed.