Commercial Motor Vehicle Drivers Research Articles

Ten-Year Cardiovascular Risk Estimation through the Framingham Risk Score among Commercial Motor Vehicle Drivers with High and Low Risk of Obstructive Sleep Apnea

Abstract Objective Obstructive sleep apnea (OSA) and cardiovascular disease (CVD) are both major medical causes of road accidents among commercial motor vehicle (CMV) drivers. The present study aimed to determine the association of the ten-year risk of developing CVD and other cardiac risk factors with the risk of developing OSA among apparently healthy CMV drivers. Materials and Methods The present cross-sectional study was conducted on 315 male CMV drivers. Demographic characteristics were collected, and the Epworth Sleepiness Scale (ESS), the Snoring, Tiredness, Observed Apnea, High Blood Pressure, Body Mass Index (BMI) > 35 kg/m2, Age > 50 Years, Neck Circumference > 40 cm, and Male Gender (STOP-Bang) questionnaire, and International Physical Activity Questionnaire-Short Form (IPAQ-SF) were filled out, and the ten-year CVD risk was calculated through the Framingham Risk Score (FRS) for each individual. Laboratory tests also were performed. The participants were divided into two groups based on the STOP-Bang score and FRS, and other CVD risk factors were compared, accordingly. The Chi-squared test, the Student t-test, analysis of variance (ANOVA), and logistic regression were used for the analysis. Results The mean age of the drivers was of 45.57 (range: 30 to 70) years. In the univariate analysis, the mean age, years of driving experience, FRS, vascular age, blood pressure, diabetes mellitus, metabolic syndrome, ESS score, BMI, and circumference of the waist and hip presented a significant association with STOP-Bang score ≥ 3 (p < 0.05). The metabolic equivalents of task (METs) for total physical activity and walking (min/week), time spent sitting (h/day), lipid profiles, smoking history, vehicle type, and shift type were statistically similar in both groups. In the multivariate analysis, a high risk of OSA was independently associated with higher FRS (odds ratio: 1.92; p < 0.001). Conclusion The STOP-Bang score presented a direct correlation with the estimated ten-year CVD risk in CMV drivers. The high risk of developing OSA among CMV drivers is accompanied by higher CVD risk factors such as old age, diabetes, hypertension, BMI, and waist and hip circumference. The FRS was statistically higher in CMV drivers with high OSA risk.

Association of Cannabinoid-receptor 1 gene with Chronic Polysubstance Use among Nigerian Male Commercial Motor Vehicle drivers

The aim of the study was to evaluate the prevalence of psychoactive substance abuse and association of single nucleotide polymorphisms in Cannabinoid-Receptor 1 (CNR1) gene with chronic polysubstance use among the Nigerian male commercial vehicle drivers selected from the three major ethnic groups in Nigeria. A-10-Panel Generic Multi Drug Urine Dip Card Test Kit was used in the study and four SNPs (rs2023239, rs806378, rs806379 and rs806381)in CNR1 were genotyped in 60 subjects (20 drivers from each ethnic group) by using Sequenom MassARRAY Genotyping System. The four target SNPs revealed the following genotypes namely rs2023239: CC (20%), CT (40%), TT (40%); rs806378: CC (100%); rs806379: AA (20%), AT (50%), TT (30%); rs806381: AA (50%), GA (50%) in cases among the Hausa drivers. However, among the Igbo drivers, the four target SNPs showed the following genotypes namely rs2023239: CC (20%), CT (40%), TT (40%); rs806378: CC (80%) CT (20%); rs806379: AA (10%), AT (50%), TT (40%) and rs806381: AA (30%), GA (70%) in cases. Additionally, the target SNPs also revealed the following genotypes namely rs2023239: CC (30%), CT (30%), TT (40%); rs806378: CC (90%), CT (10%); rs806379: AA (10%), AT (60%), TT (30%) and rs806381: AA (70%), GA (20%), GG (10%) in cases among the Yoruba drivers. The SNPs rs2023239, rs806378 and rs806381 were significantly linked with polysubstance and chronic cannabis use in the sample population (Hausa, Igbo and Yoruba) (p˂0.05). The SNP rs806379 associated significantly with polysubstance and chronic cannabis use in the Igbo drivers only (p˂0.05). Conclusively, this study provides probably the first data on the association of CNR1genetic polymorphism with chronic polysubstance use among Nigerian male commercial motor vehicle drivers.

Effect of eco-driving on commercial motor vehicle driver collision risk

Introduction: This study investigates the effect among commercial motor vehicle (CMV) drivers of the adoption of fuel-efficient driving techniques (commonly known as eco-driving) on the odds of being involved in safety-related events. Method: For 2,637 long-haul class 8 drivers employed by four carriers in Canada, information on driving style, total distance driven, and safety-related events like collisions, hard-braking, hard-turning, and stability control events were collected for each trip. Three carriers provided driving style-related data from the ISAAC instrument, which provides a score on a 0 to 100 scale that measures the degree to which a driver is using an appropriate amount of engine power according to driving conditions. The fourth carrier provided data on driving style characteristics, including fuel consumption, use of cruise control, and use of top gear. Depending on the carrier, information on speeding, driver age, and years of experience driving a commercial vehicle was also collected. Logit statistical models were developed to estimate the change in odds of a driver experiencing a safety-related event dependent on the measures of driving style. Results: A one-unit increase in the ISAAC score was associated with a 7%, 8%, 8%, and 4% reduction in the odds of having a hard-braking event, hard left-turn event, hard right-turn event, and collision, respectively. For the carrier not employing the ISAAC system, an increase of 10% in the time spent driving in top gear with steady speed near 100 km per hour (km/h) was associated with a substantial 34% decrease in stability control events. In addition, a year increase in the driver’s age, as well as a 1% increase in the amount of time spent driving using cruise control, reduced the number of hard-braking events by 9% and 3%, respectively. Conclusion/Practical Applications: The adoption of fuel-efficient driving techniques enhances the safety of CMV drivers.

Lane numbers and their impact on commercial motor vehicle crash safety: An econometric perspective

This research investigates the intricate relationship between the number of lanes on highways and injury severities sustained by commercial motor vehicle (CMV) drivers. Many studies have addressed crash determinants, but the safety implications of differing numbers of lanes remain insufficiently examined, especially during the highway planning stages. Our study fills this knowledge gap by analyzing injury severity crash factors for a varied number of lane scenarios. Employing a random parameters logit modeling framework, we differentiated injury levels for 2–4 lanes and 6–10 lanes. Key factors were identified for each number of lanes, with older, loss of vehicle control, non-collision crashes, and crashes on locations where grade or hill existed being more perilous and increasing the risk of sustaining severe injuries on 2-lane highways. For 4-lane highways, factors such as non-Oregonian drivers, older drivers, crashes that occurred during the spring season, and crashes that occurred beyond shoulders were associated with an elevated probability of being involved in severe injury crashes. Regarding highways with 6 lanes and higher, driving too fast for conditions and driver error (drowsy, fatigued, inattentive, or reckless) increases the odds of being involved in higher levels of injury crashes. To enhance truck driver safety, we recommend the implementation of electronic stability control in CMVs, moderated speeds on graded sections, improved curve markers, and robust public safety campaigns.

Work-Related Sleep Disorders: Causes and Impacts.

Insufficient sleep syndrome, shift work disorder, and obstructive sleep apnea (OSA) not only significantly impact the health of affected individuals, but also pose a threat to public safety. This article describes the clinical manifestations and impact of these sleep disorders, particularly as they pertain to workers' health and those with safety-sensitive positions. Sleep deprivation, circadian rhythm disruptions, and excessive daytime sleepiness-hallmarks of insufficient sleep, shift work disorder, and OSA, respectively-all lead to a series of cognitive deficits and impaired concentration that affect workers in a wide variety of fields. We describe the health consequences of these disorders along with treatment strategies, with a focus on current regulatory standards and the under-recognition of OSA in commercial drivers. Given its large scale, there is a need for improved guidelines and regulations for the screening, diagnosis, treatment, and long-term follow-up of OSA in commercial motor vehicle drivers. Increased recognition of the ways in which these sleep disorders impact workers will pave the way for significant improvements in occupational health and safety.

Obstructive sleep apnea and excessive daytime sleepiness among commercial motor vehicle drivers in Lusaka, Zambia.

Obstructive sleep apnea (OSA) is a risk factor for a major public health problem, car crashes, due to excessive daytime sleepiness (EDS). Commercial vehicle driving (CVD) is a hazardous occupation, having a high fatality rate worldwide. There have been no studies on EDS and OSA in Zambia despite the high rate of annual road traffic accidents (RTAs). We aim to determine the prevalence of EDS and OSA risk among CVDs in Lusaka, Zambia, to assess the impact of OSA on high RTA rates. This was a cross-sectional study. The STOP BANG questionnaire and the Epworth Sleepiness Scale were used. Consecutive sampling of drivers was done who were divided into low and high risk of OSA (HROSA). The risk factors associated with OSA in the bivariate analyses were subjected to a multivariate logistic regression model. One hundred thirty-six drivers participated in the study (all male) with a mean age of 48 ± 5 years. The prevalence of HROSA was 22.8% out of whom 67.7% also had a EDS. Only 9.6% of the total cohort had EDS without HROSA. Using Fisher's exact test, HROSA was significantly associated with older age (> 50 years, P < .001), obesity (body mass index >30, P < .001), neck circumference of > 40 cm (P = .032), and hypertension (P < .001). Snoring and EDS were significantly associated with RTAs (P < .0001 and P = .007, respectively). High risk of OSA and EDS are common among CMV drivers in Zambia and underdiagnosed. The risk factors for OSA are amenable to preventive interventions. Simpamba K, May JL, Waghat A, Attarian H, Mateyo K. Obstructive sleep apnea and excessive daytime sleepiness among commercial motor vehicle drivers in Lusaka, Zambia. J Clin Sleep Med. 2023;19(7):1191-1198.

Sleep-Disordered Breathing in Commercial Motor Vehicle Drivers

Sleep-Disordered Breathing in Commercial Motor Vehicle Drivers

Unravelling the Complexity of Irregular Shiftwork, Fatigue and Sleep Health for Commercial Drivers and the Associated Implications for Roadway Safety.

Fatigue can be a significant problem for commercial motor vehicle (CMV) drivers. The lifestyle of a long-haul CMV driver may include long and irregular work hours, inconsistent sleep schedules, poor eating and exercise habits, and mental and physical stress, all contributors to fatigue. Shiftwork is associated with lacking, restricted, and poor-quality sleep and variations in circadian rhythms, all shown to negatively affect driving performance through impaired in judgment and coordination, longer reaction times, and cognitive impairment. Overweight and obesity may be as high as 90% in CMV drivers, and are associated with prevalent comorbidities, including obstructive sleep apnea, hypertension, and cardiovascular and metabolic disorders. As cognitive and motor processing declines with fatigue, driver performance decreases, and the risk of errors, near crashes, and crashes increases. Tools and assessments to determine and quantify the nature, severity, and impact of fatigue and sleep disorders across a variety of environments and populations have been developed and should be critically examined before being employed with CMV drivers. Strategies to mitigate fatigue in CMV operations include addressing the numerous personal, health, and work factors contributing to fatigue and sleepiness. Further research is needed across these areas to better understand implications for roadway safety.

Assessing Driving Styles in Commercial Motor Vehicle Drivers After Take-Over Conditions in Highly Automated Vehicles

Assessing drivers’ behavior after transition from automated to manual driving (referred as to take-over condition) in highly automated vehicles (SAE Level 4) is a widely studied area. However, analyzing Commercial Motor Vehicle (CMV) drivers’ post-take-over behavior has received less attention, whereas it is forecasted that CMVs will be the first to vastly adopt highly automated vehicle technology. This study aims to analyze and compare CMV drivers’ driving styles in take-over conditions with continuous manual driving. Assessing driving style, which is a function of various variables and actions, provides a comprehensive understanding of the changes in post-take-over behavior. Hence, the driving behaviors of 45 CMV drivers are collected using a driving simulator, and we investigated whether the driving style is subject to driving mode (take-over or manual), automation duration, repeated take-overs, and driver’s factors. Here, drivers’ driving behavior is classified into three driving styles, normal, conservative, and risky by using Multivariate Dynamic Time Warping approach followed by <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$k$ </tex-math></inline-formula> -means clustering. Comparing driving styles in take-over and manual driving conditions showed that conservative and risky driving styles (as in more speed reduction, harder brakes, and unsafe turns) are more common in take-over conditions. Furthermore, to gain behavioral insight into the detected driving styles, Generalized Linear Models are applied to model the driving behavior indices in each driving style. Modeling results showed that long-phase automation, traffic/environmental conditions, and bad driving history deteriorate post-take-over behavior. The findings of this paper provide valuable information to automotive companies and transportation planners on the nature of take-over conditions.

Challenges in Conducting Empirical Epidemiological Research with Truck and Bus Drivers in Diverse Settings in North America.

Over 6.5 million commercial vehicle drivers were operating a large truck or bus in the United States in 2020. This career often has high stress and long working hours, with few opportunities for physical activity. Previous research has linked these factors to adverse health conditions. Adverse health conditions affect not only the professional drivers’ wellbeing but potentially also commercial motor vehicle (CMV) operators’ safe driving ability and public safety for others sharing the roadway. The prevalence of health conditions with high impact on roadway safety in North American CMV drivers necessitates empirical epidemiological research to better understand and improve driver health. The paper presents four challenges in conducting epidemiological research with truck and bus drivers in North America and potential resolutions identified in past and current research. These challenges include (1) the correlation between driving performance, driving experience, and driver demographic factors; (2) the impact of medical treatment status on the relationship between health conditions and driver risk; (3) capturing accurate data in self-report data collection methods; and (4) reaching the CMV population for research. These challenges are common and influential in epidemiological research of this population, as drivers face severe health issues, health-related federal regulations, and the impact of vehicle operation on the safety of themselves and others using the roadways.

The necessity of improving cardiovascular health in commercial motor vehicle drivers

Commercial motor vehicle (CMV) drivers have an increased risk for cardiometabolic risk factors and higher rates of cardiovascular disease relative to the general population. Lifestyle factors, including the sedentary nature of driving and lack of access to healthy foods, contribute to the disproportionately high cardiovascular disease (CVD) risk among commercial vehicle (CMV) drivers. Occupational physicals represent an important opportunity to reach populations with a high prevalence and incidence of coronary artery disease who may not otherwise seek preventive care. These visits are an opportunity to discuss primary and secondary prevention, including lifestyle topics such as diet and exercise, and potentially recommend or implement preventive medical therapy when indicated. Future iterations of licensing guidelines for drivers should seek to incorporate updated recommendations regarding diet, physical activity, and preventive pharmacologic therapies.

Developing Commercial Motor Vehicle Crash-Specific Safety Performance Functions at Interchange Ramp Terminals in Kentucky

Commercial motor vehicle (CMV) drivers often experience difficulties in turning and crossing at ramp terminals. CMV-involved crashes could cause queue spillback at ramp terminals and possibly nearby freeway mainline and crossroads. The safety and mobility of ramp terminals for accommodating CMVs is thus of significant importance. However, interchange ramp terminals have rarely been investigated in previous safety studies, especially with regard to CMV-involved crashes. This study aimed at examining CMV-related crashes that occurred at ramp terminals. Heterogeneous negative binomial (HTNB) and traditional negative binomial (NB) models were fitted and compared while developing a safety performance function (SPF) for predicting CMV crashes and identifying high-risk ramp terminals. Information on crash history and site-specific characteristics was collected at 285 ramp terminals in the state of Kentucky between 2015 and 2019. The results showed that the HTNB model outperformed the NB model in relation to various goodness-of-fit measures (e.g., likelihood ratio test “LRT”, Akaike information criterion “AIC” and McFadden Pseudo R-squared statistic). The predicted crash frequencies while applying the HTNB model were then used to identify and rank high-risk ramp terminals. Ramp terminals with signalized traffic control type, with greater average daily traffic on the exit ramp, with two or more traffic lanes on the exit ramp, and adjacent to commercial or industrial areas were found to experience more CMV crashes. Several safety countermeasures were proposed to alleviate CMV-involved crashes at ramp terminals. One example is ensuring the presence of physical medians on crossroads (or major roads) ahead of exits ramps.

Correlations of Obstructive Sleep Apnea Syndrome and Daytime Sleepiness with the Risk of Car Accidents in Adult Working Population: A Systematic Review and Meta-Analysis with a Gender-Based Approach.

Obstructive sleep apnea syndrome (OSAS) is an under-recognized clinical condition and is correlated with sleepiness and impaired cognitive function. Objectives: The primary aim of this systematic review, developed within the Sleep@OSA project, was to determine the correlations of obstructive sleep apnea syndrome, daytime sleepiness and sleep-disordered breathing with the risk of car accidents in adult working populations; a secondary aim was to analyze the epidemiologic data with a gender-based approach to identify differences between women and men in the data and in associated risk factors. Methods: Clinical trials and studies reporting data on the frequency of car accidents involving adult working population with daytime sleepiness and/or OSAS compared with a control group of participants were included. Literature searches of free text and MeSH terms were performed using PubMed, Google Scholar, the Cochrane Library and Scopus from 1952 to 3 May 2021. Results and Conclusions: The search strategy identified 2138 potential articles. Of these, 49 papers were included in the qualitative synthesis, and 30 were included in the meta-analysis. Compared with controls, the odds of car accidents were found to be more than double in subjects with OSAS (OR = 2.36; 95% CI 1.92–2.91; p < 0.001), with a similar risk between commercial motor vehicle drivers (OR = 2.80; 95% CI 1.82–4.31) and noncommercial motor vehicle drivers (OR = 2.32; 95% CI 1.84–2.34). No significant correlation was found between sleepiness and car crashes, but subjects with sleep-disordered breathing were at increased risk of car accidents (OR = 1.81; 95% CI 1.42–2.31; p < 0.001). To our surprise, although epidemiological studies on the risk of road accidents in the adult population with OSAS and daytime sleepiness are currently very abundant, specific data on the female population are not available.

Real-Time Adaptation of Driving Time and Rest Periods in Automated Long-Haul Trucking: Development of a System Based on Biomathematical Modelling, Fatigue and Relaxation Monitoring

Hours of service regulations govern the working hours of commercial motor vehicle drivers, but these regulations may become more flexible as highly automated vehicles have the potential to afford periods of in-cab rest or even sleep while the vehicle is moving. A prerequisite is robust continuous monitoring of when the driver is resting (to account for reduced time on task) or sleeping (to account for the reduced physiological drive to sleep). The overall aims of this paper are to raise a discussion of whether it is possible to obtain successful rest during automated driving, and to present initial work on a hypothetical data driven algorithm aimed to estimate if it is possible to gain driving time after resting under fully automated driving. The presented algorithm consists of four central components, a heart rate-based relaxation detection algorithm, a camera-based sleep detection algorithm, a fatigue modelling component taking time awake, time of day and time on task into account, and a component that estimates gained driving time. Real-time assessment of driver fitness is complicated, especially when it comes to the recuperative value of in-cab sleep and rest, as it depends on sleep quality, time of day, homeostatic sleep pressure and on the activities that are carried out while resting. The monotony that characterizes for long-haul truck driving is clearly interrupted for a while, but the long-term consequences of extended driving times, including user acceptance of the key stakeholders, requires further research.

Factors Associated with Colorectal Cancer Prevalence Among Long-Haul Truck Drivers in the United States.

To determine the age-adjusted association between colorectal cancer (CRC) risk factors and CRC prevalence among long-haul truck drivers (aged 21-85), after adjustment for age. Pooled cross-sectional analysis using Commercial Driver Medical Exam (CDME) data. Setting. National survey data from January 1, 2005, to October 31, 2012. 47,786 commercial motor vehicle drivers in 48 states. CRC prevalence was the primary outcome; independent variables included demographics, body mass index (BMI), and concomitant medical conditions. Kruskal-Wallis tests to analyze continuous variables; Fischer's exact tests to analyze categorical variables; univariate and multivariable logistic regression for rare events (Firth method) to quantify the association between the independent variables of interest and CRC prevalence. Odds ratios (ORs) and 95% confidence intervals (CIs) were adjusted for age, gender, years with current employer, year of exam, and BMI in a multivariate logistic regression. Many factors were statistically significant. Obesity (OR = 3.14; 95% CI = 1.03-9.61) and increasing age (OR = 1.10 per year; 95% CI = 1.07-1.13) were significantly associated with CRC prevalence. Truckers with 4 or more concomitant medical conditions were significantly more likely to have CRC (OR = 7.03; 95% CI = 1.83-27.03). Our findings highlight mutable risk factors and represent an opportunity for intervention that may decrease CRC morbidity and mortality among truck drivers, a unique population in the United States estimated to live up to 16years less than the general population.

Abstract PO-184: Investigating factors associated with colorectal cancer incidence among long-haul truck drivers in the United States

Abstract A retrospective cross-sectional analysis using Commercial Driver Medical Exam (CDME) data was performed to determine the association between colorectal cancer (CRC) risk factors and CRC incidence among long-haul truck drivers (ages 21-85), after adjustment for age. Our hypothesis was that long-haul truck drivers with poor health have a higher prevalence of CRC due to the confluence of CRC risk factors experienced by this population after adjusting for age. CRC is a common and deadly malignancy with several known risk factors, including heavy alcohol use, obesity, high consumption of processed and red meat, sedentary lifestyle, and tobacco use. Long-haul truck drivers have a high prevalence of the abovementioned risk factors, yet CRC risk has not been studied in this group. Given the reported risk factors associated with the truck driving occupation married to the lack of health literature and, a need remains to extensively examine the health of long-haul truck drivers. National survey data from January 1, 2005, to October 31, 2012, among commercial motor vehicle drivers in 48 states were examined. The CDME does not have a specific question about CRC diagnosis, text recognition was used to identify specific terms in the CDME notes and comments. Next, the entire CDME was reviewed by two researchers to determine definite versus probable CRC diagnosis, blinded to all other data. Our team also identified 311 records by searching for the following terms: colon, rectum, cancer, colorectal, CRC, and polyp. To achieve the study purpose, Kruskal-Wallis tests were employed to analyze continuous variables and Fischer's exact tests to analyze categorical variables. CRC incidence was the primary outcome, while our independent variables included demographics, body mass index, along with concomitant medication conditions verified by a medical examiner. Univariate and multivariable logistic regression was utilized to quantify the magnitude and direction of the association between our independent variables of interest and CRC incidence. Odds ratio (OR) and 95% confidence intervals (95% CI) were adjusted for age, gender, years of employment with the company, and Body Mass Index in a multivariate logistic regression. Obesity (OR=4.28; 95% CI=1.28-14.29) and increasing age (OR=1.09; 95% CI=1.06-1.12) were significantly associated with CRC incidence. Additionally, truckers with 4+ concomitant medical conditions were more likely to have CRC (OR=5.58; 95% CI=1.26 – 24.75). Despite a growing body of literature ascertaining the health of truck drivers and risk factors associated with truck driving as an occupation, knowledge gaps remain, and inadequate data is available on this population for CRC. Our findings highlight mutable risk factors and represent an opportunity for intervention that may decrease CRC morbidity and mortality among truck drivers—a unique population estimated to live up to 16 years less than the general male population. Citation Format: Jasmine A. Lopez, Ethan M. Petersen, Folasade P. May, Ellen Brooks, Matthew S. Thiese, Carson D. Kennedy, Charles R. Rogers. Investigating factors associated with colorectal cancer incidence among long-haul truck drivers in the United States [abstract]. In: Proceedings of the AACR Virtual Conference: 14th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2021 Oct 6-8. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2022;31(1 Suppl):Abstract nr PO-184.

Assessing the effect of long-automated driving operation, repeated take-over requests, and driver’s characteristics on commercial motor vehicle drivers’ driving behavior and reaction time in highly automated vehicles

Automated Commercial Motor Vehicles (CMVs) have the potential to reduce the occurrence of crashes, enhance traffic flow, and reduce the stress of driving to a larger extent. Since fully automated driving (SAE Level 5) is not yet available, automated driving systems cannot perform all driving tasks under all road conditions. Drivers need to regain the vehicle’s control when the system reaches its maximum operational capabilities. This transition from automated to manual is referred to as Take-Over Request (TOR). Evaluating driver’s performance after TORs and assessing effective parameters have gained much attention in recent years. However, few studies have addressed CMV drivers’ driving behavior after TOR and the effect of long-automated driving and repeated TORs. This paper aims to address this gap and gain behavioral insights into CMV drivers’ driving behavior after TOR and assess the effect of the duration of automated operation before TOR, repeated TORs, and driver characteristics (e.g., age, gender, education, and driving history). To accomplish this, we designed a 40-minutes experiment on a driving simulator and assessed the responses of certified CMV drivers to TORs. Drivers’ reaction time and driving behavior indices (e.g., acceleration, velocity, and headway) are compared to continuous manual driving to measure driving behavior differences. Results showed that CMV drivers’ driving behavior changes significantly after the transition to manual regardless of the number of TORs and the duration of automated driving. Findings suggest that 30 min of automated operation intensifies the effect of TOR on driving behaviors. In addition, repeated TOR improves reaction times to TOR and reduces drivers' maximum and minimum speed after TORs. Driver’s age and driving history showed significant effects on reaction time and some driving behavior indices. The findings of this paper provide valuable information to automotive companies and transportation planners on the nature of driver behavior changes due to the carryover effects of manual driving right after automated driving episodes in highly automated vehicles.

Structural Equation Model of Work Situation and Work–Family Conflict on Depression and Work Engagement in Commercial Motor Vehicle (CMV) Drivers

The shortage and aging of drivers are not problems limited to the truck industry, but are common in the broader commercial motor vehicle (CMV) industry of Korea. This study investigates the relationships between work situation, work–family conflict, depression, and work engagement of taxi, bus, and truck drivers. We extracted 512 CMV drivers from the 5th Korea Working Conditions Survey. A structural equation model (SEM) was used to investigate the impact of a work situation or work–family conflict on depression and work engagement. Results showed that 38.9% of all respondents had symptoms of depression. In the SEM, a poor work situation (standardized path coefficient = 0.250) and work–family conflict (0.117) significantly affected depression. ‘Enough time’ and ‘feeling well’ were influential variables of work situation. ‘Responsibility’ and ‘concentration’ were influential variables of work–family conflict. Additionally, depression affected work engagement (0.524). ‘Vigor’ and ‘dedication’ were influential variables of work engagement. These results show that the relationships between work situation, work–family conflict, depression, and work engagement of CMV drivers are intricately linked.

Coronary Artery Disease Evaluation and Management Considerations for High Risk Occupations: Commercial Vehicle Drivers and Pilots.

Optimal treatment of stable ischemic heart disease for those in the transportation industry is considered in the context of the individual's health, as well as with the perspective that sudden impairment could have catastrophic consequences for others. This article focuses on two high risk occupations that one may encounter in practice: commercial motor vehicle drivers and commercial pilots. This article discusses coronary heart disease in patients in high risk occupations and covers current guideline recommendations for screening, treatment, and secondary prevention. The importance of the complimentary perspectives of the regulatory agency, medical examiners, physicians, and pilot or driver are considered in this narrative review, as are considerations for future guideline updates.

What Medical Conditions Limit or Medically Disqualify Truck Drivers: A Large Cross Sectional Study.

Commercial Motor Vehicle drivers must be medically certified to obtain/maintain a commercial driver license. 88,246 exams from 2005 to 2012 were analyzed for relationships between health and certification length. Relationships were quantified using adjusted odds ratios (ORs). Most conditions and/or examination findings had statically significantly limited medical certification. Obesity > 35 kg/m2, hypertension and diabetes mellitus requiring medication were most common. Significant and meaningful relationships were found for opioid or benzodiazepine use (OR = 7.30), heart disease (OR = 5.19), musculoskeletal conditions (OR = 5.13), seizures (10.18), stroke (OR = 6.73), neurological (OR = 18.51) and vascular (OR = 11.83). Drivers with 2 or more of 13 medical conditions were statistically significantly more likely to have limited medical certification (OR = 122.35) or disqualification (OR = 4.91). Drivers with any condition are more likely to have limited medical certification. There is variability in medical certification lengths related to medical conditions and differences between examiners.