Factors related to the low-risk perception of driving after cannabis use.

INTRODUCTION: Modifying risk perceptions related to driving after cannabis use (DACU) could deter individuals from enacting this behavior, as low-risk perception is associated with DACU engagement. This study identified sociodemographic characteristics, substance use, other driving behaviors, peer norms, and psychological characteristics that are associated with lower risk perception regarding DACU. METHODS: Canadian drivers aged 17-35 who have used cannabis in the past year (n = 1,467) completed an online questionnaire. A multivariate linear regression model allowed for identifying variables associated with the low-risk perception of DACU (i.e. believing it to be safe as one's driving ability is not impaired by cannabis or by being high). RESULTS: Lower risk perception of DACU was associated with identifying as male, weekly to daily cannabis use, engagement in DACU, general risky driving behaviors, being a passenger of a driver who engages in DACU, number of friends who engage in DACU, and peer approval of DACU. Having driven under the influence of alcohol, living in urban areas, having received traffic tickets in the past three years, and declaring past-week irritability and cognitive problems were associated with holding a higher risk perception related to DACU. DISCUSSION: Road education and prevention programs should target attitudes and perceptions regarding risks shaped by sociocultural norms and past risky driving experiences. They need to reach out more specifically to drivers with the identified characteristics associated with the low-risk perception of DACU. These interventions can potentially help reduce the rate of individuals who engage in this behavior.

Perceptions and Attitudes Related to Driving after Cannabis Use in Canadian and US Adults.

BACKGROUND: This study examined the risk perceptions related to driving after cannabis use (DACU) among Canadian and US adults who used cannabis in the past six months. METHODS: Perceptions of danger, normative beliefs, perceived likelihood of negative consequences, and other driving-related variables were collected via online surveys in Canadian (n = 158; 50.0% female, 84.8% White, mean age = 32.73 years [SD = 10.61]) and US participants (n = 678; 50.9% female, 73.6% White, mean age = 33.85 years [SD = 10.12]). Driving cognitions and DACU quantity/frequency were compared between samples using univariate analyses of variance, and Spearman's (ρ) correlations were performed to examine associations between driving cognitions and DACU quantity/frequency. RESULTS: The two samples did not significantly differ in self-reported level of cannabis use, lifetime quantity of DACU, or the number of times they drove within two hours of cannabis use in the past three months (Ps > .12). Compared to US participants, Canadians perceived driving within two hours of cannabis use as more dangerous (P < 0.001, ηp2 = 0.013) and reported more of their friends would disapprove of DACU (P = 0.03, ηp2 = 0.006). There were no differences in the number of friends who would refuse to ride with a driver who had used cannabis (P = 0.15) or the perceived likelihood of negative consequences (Ps > 0.07). More favorable perceptions were significantly correlated with greater lifetime DACU and driving within two hours of use (ρ = 0.25-0.53, Ps < 0.01). CONCLUSIONS: These findings reveal differences in distal risk factors for DACU between Canada and the US and may inform prevention efforts focusing on perceptions of risk and social acceptance of DACU.

Injunctive Norms and Driving Under the Influence and Riding With an Impaired Driver Among Young Adults in Washington State.

PURPOSE: Alcohol- and cannabis-impaired driving behaviors remain a public health concern especially among young adults (i.e., ages 18-25). Limited updates to prevention efforts for these behaviors may be due, in part, to limited understanding of malleable psychosocial predictors. The current study assessed associations between perceived injunctive norms (i.e., acceptability) of driving under the influence of alcohol (DUI-A) and cannabis (DUI-C), and riding with a driver under the influence of alcohol (RWI-A) and cannabis (RWI-C) in Washington State young adults. METHODS: Participants included 1,941 young adults from the 2019 cohort of the Washington Young Adult Health Survey. Weighted logistic regressions assessed the associations between peer injunctive norms and impaired driving-related behaviors. RESULTS: A weighted total of 11.5% reported DUI-A, 12.4% DUI-C, 10.9% RWI-A, and 20.9% RWI-C at least once in the past 30 days. Overlap between the outcomes was observed, indicating some young adults had engaged in multiple impaired driving-related behaviors. After controlling for substance use frequency, weighted logistic regressions indicated more positive perceived injunctive norms were associated with nearly 2 ½ times higher odds of DUI-A, 8 times higher odds of DUI-C, 4 times higher odds of RWI-A and six and a half times higher odds of RWI-C. DISCUSSION: Results increase the understanding of how injunctive norms-a potentially malleable psychosocial factor-are associated with four impaired driving-related outcomes. Prevention programs that focus on assessing and addressing the norms of these outcomes individually and collectively, such as normative feedback interventions and media campaigns, may be helpful in reducing these behaviors.

Decision strategies while intoxicated relate to alcohol-impaired driving attitudes and intentions.

OBJECTIVE: Approximately 28 million individuals engage in alcohol-impaired driving (AID) every year. This study investigated individuals' AID decision making strategies under intoxication, their variability across the breath alcohol concentration (BrAC) curve, and the association between strategy and AID attitudes, intentions, and behavior. METHOD: Seventy-nine adults (mean 23.9 years, 57% female) who drank alcohol ≥2 days per week and lived >2 miles away from their typical drinking locations completed an alcohol administration protocol and AID decision making task. AID attitudes, intentions, and behaviors were assessed repeatedly across the BrAC curve. Bayesian cognitive modeling identified decision strategies used by individuals on the AID decision making task, revealing whether alcohol consumption level and/or ride service cost factored into individuals' decisions to drive while impaired or obtain a ride. Additional analyses tested whether AID attitudes and intentions were related to individuals' decision strategies. RESULTS: Two decision strategies were examined on the ascending and descending limbs of the BrAC curve: compensatory (both consumption level and ride service cost factored into AID decisions) and non-compensatory (only consumption level factored into AID decisions). Switching to a compensatory strategy on the descending limb was associated with lower perceived intoxication, perceiving AID as less dangerous, and being willing to drive above the legal BrAC limit. CONCLUSIONS: Results suggest that risk for engaging in AID is higher for those using a cost-sensitive, compensatory strategy when making AID decisions under intoxication. Future research is needed to test whether AID countermeasures (e.g., subsidized ride services) are differentially effective according to decision strategy type. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Driving under the influence of alcohol during the COVID-19 pandemic.

AIM: The main objective of this study was to evaluate the effects of the COVID-19 pandemic on the pattern of alcohol use in drivers. MATERIALS: and methods. At the National Institute of Legal Medicine from Bucharest, we performed a retrospective study on toxicology reports between January 1st, 2019 and December 31st, 2020. Breath alcohol concentration (BrAC) was tested using Dräger breathalyzers by police units at the scene, and blood alcohol concentration (BAC) was evaluated using headspace gas chromatography. Most drivers gave two blood samples, separated by a one-hour interval, case in which they could request a retrograde extrapolation of the BAC at the time when they were stopped in traffic. RESULTS: The distribution of the number of cases depending on the month showed a sharp decline in the first six months of the lockdown, with a slow upward trend afterward. Mean overall values for BrAC were 0.49 +/- 0.40 mg/L, for 1st sample BAC - 1.15 +/- 0.99 g/L and for 2nd sample BAC - 1.29 +/- 0.81 g/L. Mean values obtained for BrAC were 0.48 +/- 0.39 mg/L before the pandemic and 0.52 +/- 0.43 mg/L during the pandemic. The increase was similar in absolute numbers in both male and female drivers (0.03 versus 0.04 mg/L respectively for BrAC and 0.02 g/L for both genders for 1st sample BAC). However, the percentage increase was significantly higher in women. There were 253 cases in which BrAC had values between 0.01 and 0.05, of which 138 occurred before the pandemic and 115 during the pandemic, the increase being highly statistically significant. The percentage of drivers with BAC levels below and above 0.8 g/L (the threshold value for which DUI is a felony in Romania) were similar before and during the pandemic. CONCLUSIONS: During the lockdown, the number of alcohol tests in traffic has decreased significantly. This reduction was not associated with statistically significant changes in BrAC or BAC. We have seen a substantial increase in the number of minimally elevated BrAC and negative BAC cases, changes that could be caused by an increased use of alcohol-based hand sanitizers.

Modeling the influence of 0.03%, 0.05% and 0.08% blood alcohol concentrations on lane positioning and steering control of Indian drivers.

OBJECTIVE: Alcohol-impairment of drivers has significant influence on road traffic safety; however, no experimental research has been conducted on the lateral driving control of Indian drivers. Therefore, the present study investigates the effects of different Blood Alcohol Concentration (BAC) levels (0%, 0.03%, 0.05% and 0.08%) and driver attributes on the lane positioning and steering control of Indian drivers. METHOD: A driving simulator experiment was designed where 82 adult licensed drivers (62 males, 20 females) completed driving on the simulated urban arterial road environment under the influence of varying BACs. Lateral driving performance measures associated with lane positioning (lane position variability) and steering control of drivers (steering angle variability and steering reversal rates (SRR)) were analyzed. RESULTS: The findings reported that lane position variability was significantly influenced only at 0.08% BAC (5.8% increment); no significant influence was observed at 0.03% and 0.05% BACs. Compared to 0% BAC, steering angle variability increased by 0.105 degrees or 15.7%, 0.142 degrees or 21.4%, and 0.176 degrees or 25.7% at 0.03%, 0.05% and 0.08% BACs respectively. No significant differences were observed between the sober-state driving and alcohol-impaired driving at 1ο and 5ο SRR. However, 10ο SRR was found to be higher by 36%, 65% and 92% at 0.03%, 0.05% and 0.08% BACs compared to 0% BAC. Among the driver attributes, male drivers displayed higher impairment in lane positioning behavior as compared to female drivers. One-year increase in drivers' age reduced the lane position variability by 0.6%. Drivers who performed regular physical exercise were found to have better lateral control on the vehicle, as observed in their steering angle variability. Prior crash history had negative association with the steering reversal rates, indicating that drivers who have previous experience of crash involvement show better steering control than the drivers without any crash experience. CONCLUSION: In conclusion, the outcomes of this study provide novel insights into the alcohol-impaired lateral vehicle control of Indian drivers which can assist in policy interventions aiming to reduce crashes with alcohol as a major crash causation factor.

Convicted drinking and driving offenders: Comparing alcohol use before and after the pandemic outbreak.

BACKGROUND: Before the COVID-19 pandemic, very little was known about the impact of social isolation on individuals' alcohol use and misuse. This study examines how socially isolated individuals with a history of heavy drinking used alcohol during the pandemic. METHODS: Data for this study came from an add-on to the Managing Heavy Drinking (MHD) longitudinal study of drivers convicted of DWI that was conducted in Erie County, New York. Pre-COVID information (October 2019-March 2020) was augmented with a COVID-19 questionnaire collected between July and August 2020. A total of 92 participants completed the COVID-19 survey. RESULTS: The sample of problem drinkers showed a significant increase after the pandemic outbreak in the average number of drinking days from 1.99 to 2.49 per week (p = 0.047), but a significant decrease in the average number of drinks per drinking day, from 3.74 to 2.74 (p = 0.003). The proportion of individuals who drank more frequently was greater among those who, before the outbreak had an Alcohol Use Disorders Identification Test (AUDIT) score <8 (26% increase) compared with those with an AUDIT score of >8 (13%). Alcohol treatment was also associated with the frequency of drinking, with individuals who were not in alcohol treatment showing a 16% increase in frequency compared with a 10% increase among those in treatment. Further, individuals who, after the outbreak worried about their health (30%) or finances (37%) reported greater increases in the frequency of drinking than those who did not worry about their health (17%) or finances (10%). CONCLUSIONS: Overall, the individuals in our sample showed small changes in the frequency andheaviness of drinking after the outbreak of COVID-19, effects that opposite in direction from one another and thus resulted in no overall change in drinks consumed. Nonetheless, we identified factors that influenced the effects of the pandemic on drinking behavior among individuals convicted of DWI, which emphasizes the need to individualize these individuals' treatment, particularly in the context of dramatic environmental change.

Can't simply roll it out: Evaluating a real-world virtual reality intervention to reduce driving under the influence.

Driving under the influence (DUI) increases the risk of crashes. Emerging technologies, such as virtual reality (VR), represent potentially powerful and attractive tools for the prevention of risky behaviours, such as DUI. Therefore, they are embraced in prevention efforts with VR interventions primed to grow in popularity in near future. However, little is known about the actual effectiveness of such DUI-targeting VR interventions. To help fill the knowledge gap, this study explored the effects of one VR intervention as delivered in the real world. Using pre and post test design, including an intervention group (n = 98) and a control group (n = 39), the intervention evaluation examined young drivers' (aged 18 to 25, no known history of DUI) intention and self-reported behaviour three months after the intervention as compared to the baseline. The results did not provide evidence for statistically significant effects of the VR intervention on self-reported DUI behaviour during the three months post intervention and DUI intention at three months post intervention. Such results might be due to the fact that the recruited participants generally self-reported little DUI behaviour, i.e. positively changing behaviour that is already positive is inherently challenging. Nevertheless, the results question the utility of funding the roll-out of arguably attractive technologies without a thorough understanding of their effectiveness in particular settings. To improve the potential for future positive outcomes of such interventions, we provide suggestions on how VR software might be further developed and, subsequently, leveraged in future research to improve the likelihood for behavioural change, e.g. by collecting, analysing and presenting objective driving performance data. Alternatively, future endeavours might focus on participants with known DUI history and examine the effects of the VR intervention for this particular higher-risk group.

Changes in Alcohol Use and Drinking and Driving Outcomes From Before Arrest for Driving Under the Influence to After Interlock Removal.

BACKGROUND: Half of the offenders convicted of impaired driving in the United States are sentenced to install alcohol ignition interlock devices (IIDs), which prevent them from starting their vehicles if they have been drinking. No research has yet explored offenders' patterns of alcohol consumption and driving under the influence of alcohol (DUI) from the time before the arrest to the time period after the IID is installed. This study aims to fill that gap in knowledge. METHODS: Using the Timeline Follow-back interview procedure, we assessed the daily drinking of 153 convicted DUI offenders' self-reported total alcohol consumption and rates of self-reported driving after drinking over 4 phases: before DUI arrest, between arrest and IID installation, during the phase on the interlock, and after the interlock is removed. Because information about behaviors in each period was not available for every participant, comparisons were made using paired-sample contrasts. RESULTS: Compared with before the arrest, total alcohol use decreased by 50% in the 4-month phase following arrest and before IID installation, though it did not change much afterward. The frequency of drinking and driving decreased sharply after the arrest (-82%), with further decrease upon installation of the interlock (-58%, p = 0.05). The frequency of drinking and driving after the IID was removed returned to preinstallation drinking and driving status (+58%, p = 0.01). CONCLUSIONS: Participants made significant adjustments to their drinking behavior by adhering to the traditional DUI driving restrictions in the postarrest phase. Although installation of an IID was not associated with a significant change in drinking, it further reduced the frequency of drinking and driving. Evaluations of the IID experience should take into account information on an individual's drinking and DUI behaviors not only before the IID was installed, but before the individual was arrested.

Analysis of drink-driving behavior: Considering the subjective and objective factors of drivers.

OBJECTIVE: Drink-driving is one of the key behavioral risk factors in road traffic safety. The main purposes of this study are the identification of the influence of drivers' subjective and objective factors on drink-driving behavior and the correlation between subjective and objective factors to design targeted measures for the prevention and control of drink-driving behavior. METHODS: To analysis the influence of the subjective and objective factors on the behavior of alcohol value simultaneously. A Bayesian structural equation model is conducted with the data collected via questionnaire issued on the Internet in China. RESULTS: The results using the Bayesian structural equation model reveals that the subjective factors (e.g., drivers' behavior intention and perceived behavioral control) and objective factors (e.g., age, gender, and driving years of drivers) significantly affect drink-driving behaviors. Drivers' behavior intention is the strongest predictor, and perceived behavioral control also has a significant influence on drink-driving. Drivers who are male, older, lower driving years, driving a motorcycle or car and noncommercial vehicle have a higher probability in drink-driving. The results also suggest that there is a certain correlation between the driver's subjective and objective factors. For instance, male drivers have a more positive attitude toward drink-driving behaviors, drivers over thirty years old more cling to the region's alcohol culture and feel less guilty about drink-driving than youngsters, and truck or bus drivers perceived more disapproval of drink-driving behavior from their significant others. CONCLUSIONS: A more nuanced understanding of the influence of drivers to drink-driving behavior can be found in these results. These results about the influence mechanism of subjective and objective factors on drink-driving behavior of this study have implications for governments and other interested bodies for better targeting and delivery of public education campaigns and interventions.

Driving under the influence of drugs or alcohol: Predicting the intentions of young drivers.

Objectives: Driving under the influence (DUI) of drugs or alcohol impairs driving performance and, as a result, increases the risk of crashes. The risk of DUI is five-fold higher for young drivers (aged 18-25 years), but little is known about what determines their DUI intentions. This study applied an extended model of the Theory of Planned Behavior (TPB) to address the research question of what factors might influence young drivers' future intentions to DUI. Methods: This study used a survey obtaining data from 329 young drivers (Mage = 20.92 years, SD = 2.16) in Australia. Beyond the standard TPB measures of attitudes, subjective norms and perceived behavioral control (PBC), the current study included demographic variables and additional predictors (i.e., moral norm, peers' norm, perceived risk, impulsivity and past DUI behavior). Results: A vast majority of the participants (85.1%) selected the maximum (9, never), meaning that they had no intention to DUI in the future. Overall, a stepwise multilevel logistic regression analysis (Step 1: demographics, Step 2: TPB measures, and Step 3: additional predictors) explained between 30.1% and 52.9% of the variance in DUI intentions. It showed past DUI behavior as the strongest predictor of DUI intention, followed by instrumental attitude and descriptive norms. Conclusions: This study explored an extended TPB model to understand young drivers' DUI intentions better. With this new knowledge of understanding the factors that influence DUI, researchers and practitioners can create interventions and strategies that are better tailored to the population of young drivers at higher risk.

A comparison of driving related skills impaired by ethanol and zopiclone.

Objective: Ethanol and zopiclone are both sedating drugs that impair traffic relevant skills, but that show vast differences in epidemiological traffic risk. One explanation for this could be that they impair various kinds of skills differently, but this is less previously studied. The aim of this study was to compare effects of zopiclone and ethanol on a large battery of computerized psychomotor and cognitive tests according to different test classifications. Methods: Ethanol (50 grams), zopiclone 5 mg, zopiclone 10 mg or placebo was administered in a randomized trial with a cross-over design. Blood was sampled nine times after administration and analyzed for zopiclone and ethanol using fully validated methods. The computerized tests Connors Continuous Performance Test (CPT), Stockings of Cambridge (SOC) and choice reaction time (CRT) was performed at baseline and after administration. The three tests yielded fifteen different test components, which were categorized according to the three well-known behavior levels (automative behavior, control behavior and executive planning). Secondly, they were categorized into tests measuring "reaction time", "impulsivity" and "attention/cognition". Results: On all tests belonging to behavior level 1 and on all tests measuring "reaction time", more subjects were impaired by zopiclone than ethanol. On all tests measuring "impulsivity", more subjects were impaired by ethanol than zopiclone. Conclusion: Zopiclone and ethanol both lead to impairment, but have a different profile on what kind of tests and neurocognitive functions they mostly impair. This could be important in the understanding of the differences in traffic risk connected to these two drugs.

Long-term effectiveness of the alcohol ignition interlock programme: A retrospective cohort study in the Netherlands.

This article provides an evaluation of the long-term effectiveness of the Alcohol Ignition Interlock Programme (AIIP) on recidivism. A retrospective cohort design was used to compare the known reoffending behaviour of 1676 AIIP participants with that of 907 persons in a control group, consisting of offenders who committed an AIIP-worthy driving-under-the-influence (DUI) offence that was not reported to the Dutch driving license authority. Persons in the control group were not sanctioned with an AIIP, but had their case settled in the criminal court. Our outcome measure was the percentage of offenders who committed at least one new DUI offence within the follow-up period. Results indicate that the percentage of repeat offenders in the AIIP group was lower than in the control group. Additional analyses indicate that were an AIIP to be imposed alongside a criminal settlement, a recidivism reduction of 4 percentage points (4 % versus 8 %) could be expected. This would translate to a relative decrease of 54 %. Explanations for these findings are discussed.

Validity and reliability of a driving simulator for evaluating the influence of medicinal drugs on driving performance.

RATIONALE: Although driving simulators (DS) are receiving increasing attention due to concern over traffic accidents under the influences of drugs, few DS are recognized for their reliability and validity. Therefore, the development of an evaluation system using DS for driving performance is urgently needed. OBJECTIVES: To investigate whether the standard deviation of lateral position (SDLP) increases with blood alcohol concentration (BAC) using a DS with reliability and calculate the SDLP threshold from the difference between BAC levels of 0 and 0.05%. METHODS: Twenty healthy Japanese men performed the DS tasks up to 60 min in Study 1 and DS tasks twice at 1-week intervals in Study 2. Twenty-six healthy men conducted the same DS tasks under BAC level (0, 0.025, 0.05, and 0.09%) in double-blind, randomized, crossover trial in Study 3. The primary outcome was SDLP in a road-tracking test. The test-retest reliability of DS data was assessed, and the estimated difference in SDLP between BAC levels of 0 and 0.05% was calculated using a linear regression model. RESULTS: The cumulative SDLP values at 5-min intervals were stable, and the intraclass correlation coefficient for its values was 0.93. SDLP increased with BAC in a concentration-dependent manner. The predicted ΔSDLP value for the difference between BAC levels of 0 and 0.05% was 9.23 cm. No participants dropped out because of simulator sickness. CONCLUSIONS: The new DS used in these studies has reliability, validity, and tolerability and is considered suitable for evaluating the influence of drugs on driving performance.

Acute administration of oxycodone, alcohol, and their combination on simulated driving-preliminary outcomes in healthy adults.

RATIONALE: Epidemiological data indicate that drivers testing positive for an opioid drug are twice as likely to cause a fatal car crash; however, there are limited controlled data available. OBJECTIVES: The primary aim of this study was to assess the effects of a therapeutic dose range of oxycodone alone and in combination with alcohol on simulated driving performance. METHODS: Healthy participants (n = 10) completed this within-subject, double-blind, placebo-controlled, randomized outpatient study. Six 7-h sessions were completed during which oxycodone (0, 5, 10 mg, p.o.) was administered 30 min before alcohol (0, 0.8 g/kg (15% less for women), p.o.) for a total of 6 test conditions. Driving assessments and participant-, observer-rated, psychomotor and physiological measures were collected in regular intervals before and after drug administration. RESULTS: Oxycodone alone (5, 10 mg) did not produce any changes in driving outcomes or psychomotor task performance, relative to placebo (p > 0.05); however, 10 mg oxycodone produced increases in an array of subjective ratings, including sedation and impairment (p < 0.05). Alcohol alone produced driving impairment (e.g., decreased lateral control) (p < 0.05); however, oxycodone did not potentiate alcohol-related driving or subjective effects. CONCLUSIONS: These preliminary data suggest that acute doses of oxycodone (5, 10 mg) do not significantly impair acuity on laboratory-based simulated driving models; however, 10 mg oxycodone produced increases in self-reported outcomes that are not compatible with safe driving behavior (e.g., sedation, impairment). Additional controlled research is needed to determine how opioid misuse (higher doses; parenteral routes of administration) impacts driving risk.

Impact of cannabis and low alcohol concentration on divided attention tasks during driving.

OBJECTIVE: To assess divided-attention performance when driving under the influence of cannabis with and without alcohol. Three divided-attention tasks were performed following administration of placebo, cannabis, and/or alcohol. METHODS: Healthy adult cannabis users participated in 6 sessions, receiving combinations of cannabis (placebo/low-THC/high-THC) and alcohol (placebo/active) in randomized order, separated by washout periods of ≥1 week. At 0.5 hours post-dosing, participants performed simulator drives in the University of Iowa National Advanced Driving Simulator (NADS-1), a full vehicle cab simulator with a 360° horizontal field of view and motion base that provides realistic feedback. Drives contained repeated instances of three tasks: a side-mirror task (reaction to a triangle appearing in the side-mirrors), an artist-search task (select a specified artist from a navigable menu on the vehicle's console), and a message-reading task (read aloud a message displayed on the console). Blood THC and breath alcohol concentration (BrAC) were interpolated using individual power curves from samples collected approximately 0.17, 0.42, 1.4, and 2.3 hours post-dose. Driving measures during tasks were compared to equal-duration control periods occurring just prior to the task. Performance shifts, task completion, and lane departures were modeled relative to blood THC and BrAC using mixed-effects regression models. RESULTS: Each 1 µg/L increase in blood THC concentration predicted increased odds of failing to complete the artist-search task (OR: 1.05, 95% CI: 1.01-1.11, p = 0.046), increased odds of selecting at least one incorrect response (OR: 1.05, 95% CI: 1.00-1.09, p = 0.041), declines in speed during the side-mirror task (0.005 m/s, 95% CI: 0.001-0.009, p = 0.023), and longer lane departure durations during the artist-search task (0.74% of task-period, 95% CI: 0.12-1.36 p = 0.020). BrAC (approximately 0.05%) was not associated with task performance, though each 0.01 g/210 L increase predicted longer departure durations during the side-mirror task (1.41% of task-period, 95% CI: 0.08-2.76, p = 0.040) and increased standard deviation of lane position in the message-reading task (0.61 cm, 95% CI: 0.14-1.08, p = 0.011). CONCLUSIONS: With increasing medical and legal cannabis use, understanding the impact of acute cannabis use on driving performance, including divided-attention, is essential. These data indicate that impaired divided-attention performance is a safety concern.

EEG biomarkers acquired during a short, straight-line simulated drive to predict impairment from cannabis intoxication.

OBJECTIVE: As cannabis use becomes more widely accepted, there is growing interest in its effects on brain function, specifically how it may impact daily functional activities such as driving, operating machinery, and other safety-related tasks. There are currently no validated methods for quantifying impairment from acute cannabis intoxication. The objective of this study was to identify neurophysiological correlates associated with driving simulator performance in subjects who were acutely intoxicated with cannabis. These signatures could help create an EEG-based profile of impairment due to acute cannabis intoxication. METHODS: Each subject completed a three-visit study protocol. Subjects were consented and screened on the first visit. On the second and third visits, subjects were administered either 500 mg of cannabis with 6.7% delta-9-tetrahydrocannabinol (THC) or placebo using a Volcano© Digit Vaporizer in a counterbalanced fashion. EEG was acquired from subjects as they performed a series of neurocognitive tasks and an approximately 45-minute simulated drive that included a rural straight-away absent of any other cars or obstacles during the final 10 minutes.EEG data was acquired using a STAT X24 wireless sensor headset during a simulated driving scenario from 10 subjects during the THC and placebo visits. Metrics of driving performance were extracted from the driving simulator and synchronized with EEG data using a common clock. RESULTS: A within-subjects analysis showed that the standard deviation of lane position (SDLP) was significantly worse and heart rate was elevated during the dosed visit compared to the placebo visit. Consistent with our prior findings, EEG power in the Theta frequency band (4-7 Hz) in the dosed condition was significantly decreased from the placebo condition. Theta power was negatively correlated with the SDLP driving performance metric, while there were no significant correlations between any EEG measure and SDLP in the placebo condition. CONCLUSIONS: These results, in combination with prior work on the effect of cannabis intoxication during neurocognitive tasks, suggest that neurophysiological signatures associated with acute cannabis intoxication are robust and consistent across tasks, and that these signatures are significantly correlated with impaired performance in a driving simulator. Taken together, EEG data acquired during a short neurocognitive testbed and during a simulated drive may provide specific profiles of impairment associated with acute cannabis intoxication. Further research is needed to establish the impaired cognitive processes associated with these EEG biomarkers.

Context, acute tolerance, and subjective response affect alcohol-impaired driving decisions.

RATIONALE: Alcohol intoxication produces effects that can impair judgment and increase engagement in risky behaviors, including alcohol-impaired driving (AID). Real-world AID decisions are informed by contextual circumstances and judgments of associated risk. How individuals vary in their AID decision-making across contexts and whether subjective alcohol responses (stimulation, sedation, acute tolerance) differentially affect AID decisions are critical, but under-studied research questions. OBJECTIVES: We systematically investigated predictors of AID decisions at different hypothetical driving distances across the blood alcohol concentration (BAC) curve. METHODS: Young adults (n = 40; 55% female) completed two laboratory sessions in a within-subjects alcohol/placebo design. At multiple points along the BAC curve (M peak BAC = 0.101 g%), participants rated their subjective intoxication, stimulation, sedation, and perceived dangerousness of driving prior to indicating their willingness to drive distances of 1, 3, and 10 miles. Multilevel mixed models assessed within- and between-person predictors of the maximum distance participants were willing to drive at matched BACs on the ascending and descending limb. RESULTS: Under intoxication (but not placebo), participants were willing to drive greater distances on the descending versus ascending limb. At the momentary level, participants were willing to drive further when they felt less intoxicated, stimulated, and sedated, and perceived driving as less dangerous. CONCLUSIONS: Individuals differed in the distance they were willing to drive as a function of indicators of intoxication, implicating driving distance as an important contextual factor relevant to AID decisions. Individuals may simultaneously perceive themselves as "unsafe" to drive, but "safe enough" to drive short distances, particularly when BAC is falling.

An investigation on the risk factors associated with driving errors under the influence of alcohol using structural equation modeling.

Objective: Driving errors contribute to traffic crashes and thus the causal factors associated with driving errors are of great interest to the road safety researchers. The present study attempts to identify and quantify the effects of various risk factors that are likely to influence driving error with the application of structural equation modeling (SEM). These risk factors include blood alcohol concentration (BAC) levels (0%, 0.03%, 0.05%, and 0.08%), different driving environments (rural, urban), and driver attributes (such as age, gender, education).Method: Eighty-two licensed drivers participated in a driving simulator experiment. They completed driving under the influence of 4 BAC levels in the driving environments within the framework of a full-factorial within-subjects design. Driving error was modeled as an unobserved latent variable based on several driving simulator indicators. An SEM approach was utilized to examine the influence of BAC level, driving environment, and driver attributes on the latent variable pertaining to driving error.Results: The findings suggest the suitability of an SEM approach in the investigation of driving error. The results revealed that all 3 positive BACs (0.03%, 0.05%, and 0.08%) had a significant positive influence on driving error compared to 0% BAC, and the tendency toward driving error increased with increasing BAC (factor loadings for 0.03%, 0.05%, and 0.08% BAC were 0.22, 0.31, and 0.37, respectively). Moreover, driving in an urban environment led to more driving errors compared to a rural environment, including sober drivers. Among the driver attributes, gender and awareness about drink and drive laws were the only factors influencing driving error.Conclusion: This study highlights a novel approach to investigate driving error by modeling it as a latent variable instead of modeling individual performance measures. The successful execution of SEM in alcohol impairment research may serve as a significant step in the human factors field moving from piecemeal analysis to a combined analysis where interrelationships among numerous risk factors and driving error can be established. The study outcomes may serve as a reference while developing strategies to enhance road traffic safety where special emphasis can be given to the critical risk factors influencing driving error identified in the study.

Injury patients' perceptions of drink-driving: A qualitative assessment of drink-driving behavior in Moshi, Tanzania.

BACKGROUND: Globally, about 2.3 billion people are current alcohol drinkers, and 283 million have an alcohol use disorder. Alcohol use while driving is a major contributor to road traffic injuries (RTI). We need to understand the culture and perception of drink-driving in this setting to understand why people continue to drink drive and allow policymakers to develop more effective ways to address drink-driving behavior. This study aims to qualitatively determine what injury patients, their families, and community advisory board members in Tanzania believe about drink-driving to help inform policies to address this problem. METHODS: The semi-structured focus group was designed based on the grounded theory and assessed using thematic analysis. Focus groups participants were a convenience sample of injury patients, their families, and community advisory board (CAB) members. Analysis was iterative throughout the study. All transcripts were coded using a thematic narrative approach. Representative quotes for each theme were then selected based on comparative analysis of coding with input from research team members. RESULTS: A total of ten focus groups were conducted (4 patient, 4 family, and 2 CAB) with a total of 104 participants (37 females and 67 males). The normalization of drinking among drivers has allowed this behavior to become ingrained in the culture. Participants expressed notions that passengers are responsible for their own safety, rather than drivers being responsible for their passengers. Most participants believe it is a citizen's duty to inform the police of suspected drink-driving, however there were differing opinions about how effective informed police officers can be in practice. Focus group discussions between all three population types highlighted major themes of 'drinking is ingrained in boda boda driver culture', 'individuals have a personal responsibility to address drink-driving', and a 'police enforcement on drink-driving is necessary'. CONCLUSIONS: Normalization of drink-driving in commercial driver culture creates a dangerous environment for passengers which can be mitigated by education and health promotion. As most passengers already take personal responsibility for their own road traffic safety, they may be likely to make use of safe ride options, if available. While legislation is in place against drink-driving, police officers need to be empowered with appropriate training and funding to enforce them.