Identifying factors that predict persistent driving after drinking, unsafe driving after drinking, and driving after using cannabis among young adults

Risk factors associated with driving after marijuana use among West Virginia college students during the COVID-19 pandemic

OBJECTIVES

The purpose of this study was to assess sociodemographic and behavioral risk factors associated with driving after marijuana use (DAMU) among West Virginia college students.

METHODS

Participants were recruited from West Virginia University between September and November 2022. The study sample was restricted to students who were ≥18 years of age; reported recently driving; possessed a current, valid driver's license from any US state; and were enrolled for at least one credit hour in the Fall 2022 semester.

RESULTS

Among respondents (N = 772), 28.9% reported DAMU. Students who had a GPA of B (adjusted odds ratio [AOR]: 2.17, 95% confidence interval [CI]: 1.06-4.42), smoked or ingested marijuana in the past year (AOR: 26.51, 95% CI: 10.27-68.39), drove after drinking (AOR: 2.38, 95% CI: 1.18-4.79), and used both marijuana and alcohol concurrently and then drove (AOR: 10.39, 95% CI: 2.32-46.54) associated with DAMU. Individuals who felt the behavior was somewhat dangerous or not dangerous or thought their peers approved of DAMU showed significant associations with DAMU.

CONCLUSIONS

As DAMU was prevalent, future interventions that raise awareness of the danger and potential consequences of DAMU may be needed to reduce this risky behavior on college campuses.

Risk Factors Associated With Driving After Marijuana Use Among US College Students During the COVID-19 Pandemic

PURPOSE

To assess the sociodemographic and behavioral risk factors associated with driving after marijuana use among US college students.

METHODS

A secondary analysis used the fall 2020 and spring 2021 American College Health Association- National College Health Assessment III and the dataset was restricted to college students ≥18 years of age who reported recent driving and marijuana use. Associations between risk factors and driving after marijuana use were estimated using multivariable logistic regression.

RESULTS

A total of 29.9% (n = 4,947) of the respondents reported driving after marijuana use. Males (adjusted odds ratio [AOR]: 1.64, 95% confidence interval [CI]: 1.48-1.82), non-Hispanic Black (AOR: 1.32, 95% CI: 1.02-1.71), sexual minorities (AOR: 1.19, 95% CI: 1.07-1.31), individuals with an alcohol or substance use disorder (AOR: 1.44, 95% CI: 1.08-1.91), anxiety (AOR: 1.20, 95% CI: 1.06-1.36), higher suicidality (AOR: 1.18, 95% CI: 1.07-1.31), and those who also drank and drove (AOR: 3.18, 95% CI: 2.84-3.57) had a higher risk of driving after marijuana use.

DISCUSSION

Future research should focus on increasing awareness of driving after marijuana use and prevention programs and/or strategies on college campuses regarding driving after marijuana use for these groups to reduce this risky behavior.

Associations of cannabis use with motor vehicle crashes and traffic stops among older drivers: AAA LongROAD study

BACKGROUND

Acute cannabis use is associated with a higher risk of motor vehicle crashes (MVC). This study aimed to determine if self-reported past-year cannabis use is associated with MVC or traffic stops among older drivers.

METHODS

This cross-sectional analysis used data from a multi-center study enrolling active drivers aged 65-79 years. Data regarding cannabis use, MVC, and traffic stops (i.e., being pulled over by police, whether ticketed or not) within the previous 12 months were collected through participant interviews. Log-binomial regression models examined associations of past-year cannabis use with MVC and traffic stops, adjusting for site and sociodemographic and mental health characteristics.

RESULTS

Of 2,095 participating older drivers, 186 (8.88%) used cannabis in the past year but only 10 (<0.5%) within an hour before driving in the last 30 days; 11.41% reported an MVC and 9.45% reported a traffic stop. Past-year cannabis users had a higher prevalence of MVC (adjusted prevalence ratio [aPR] = 1.38; 95%CI: 0.96, 2.00; p = 0.086) and traffic stops (aPR = 1.58; 1.06, 2.35; p = 0.024).

CONCLUSIONS

Past-year cannabis use was associated with increased traffic stops, which are correlated modestly with increased MVC in past studies and may indicate impaired driving performance. We did not find a statistically significant association of past-year cannabis use with MVC, which may indicate limited sustained effects on driving performance from periodic use among older adults, who report rarely driving immediately after use.

In-Vehicle Alcohol Detection Using Low-Cost Sensors and Genetic Algorithms to Aid in the Drinking and Driving Detection

Worldwide, motor vehicle accidents are one of the leading causes of death, with alcohol-related accidents playing a significant role, particularly in child death. Aiming to aid in the prevention of this type of accidents, a novel non-invasive method capable of detecting the presence of alcohol inside a motor vehicle is presented. The proposed methodology uses a series of low-cost alcohol MQ3 sensors located inside the vehicle, whose signals are stored, standardized, time-adjusted, and transformed into 5 s window samples. Statistical features are extracted from each sample and a feature selection strategy is carried out using a genetic algorithm, and a forward selection and backwards elimination methodology. The four features derived from this process were used to construct an SVM classification model that detects presence of alcohol. The experiments yielded 7200 samples, 80% of which were used to train the model. The rest were used to evaluate the performance of the model, which obtained an area under the ROC curve of 0.98 and a sensitivity of 0.979. These results suggest that the proposed methodology can be used to detect the presence of alcohol and enforce prevention actions.

Reduced social distancing early in the COVID-19 pandemic is associated with antisocial behaviors in an online United States sample

Antisocial behaviors cause harm, directly or indirectly, to others' welfare. The novel coronavirus pandemic has increased the urgency of understanding a specific form of antisociality: behaviors that increase risk of disease transmission. Because disease transmission-linked behaviors tend to be interpreted and responded to differently than other antisocial behaviors, it is unclear whether general indices of antisociality predict contamination-relevant behaviors. In a pre-registered study using an online U.S. sample, we found that individuals reporting high levels of antisociality engage in fewer social distancing measures: they report leaving their homes more frequently (p = .024) and standing closer to others while outside (p < .001). These relationships were observed after controlling for sociodemographic variables, illness risk, and use of protective equipment. Independently, higher education and leaving home for work were also associated with reduced distancing behavior. Antisociality was not significantly associated with level of worry about the coronavirus. These findings suggest that more antisocial individuals may pose health risks to themselves and their community during the COVID-19 pandemic.

Reduced social distancing early in the COVID-19 pandemic is associated with antisocial behaviors in an online United States sample

Antisocial behaviors cause harm, directly or indirectly, to others' welfare. The novel coronavirus pandemic has increased the urgency of understanding a specific form of antisociality: behaviors that increase risk of disease transmission. Because disease transmission-linked behaviors tend to be interpreted and responded to differently than other antisocial behaviors, it is unclear whether general indices of antisociality predict contamination-relevant behaviors. In a pre-registered study using an online U.S. sample, we found that individuals reporting high levels of antisociality engage in fewer social distancing measures: they report leaving their homes more frequently (p = .024) and standing closer to others while outside (p < .001). These relationships were observed after controlling for sociodemographic variables, illness risk, and use of protective equipment. Independently, higher education and leaving home for work were also associated with reduced distancing behavior. Antisociality was not significantly associated with level of worry about the coronavirus. These findings suggest that more antisocial individuals may pose health risks to themselves and their community during the COVID-19 pandemic.

Effect of Road Markings and Traffic Signs Presence on Young Driver Stress Level, Eye Movement and Behaviour in Night-Time Conditions: A Driving Simulator Study

The study investigates how the presence of traffic signalling elements (road markings and traffic signs) affects the behaviour of young drivers in night-time conditions. Statistics show that young drivers (≤30 years old) are often involved in road accidents, especially those that occur in night-time conditions. Among other factors, this is due to lack of experience, overestimation of their ability or the desire to prove themselves. A driving simulator scenario was developed for the purpose of the research and 32 young drivers took two runs using it: (a) one containing no road markings and traffic signs and (b) one containing road markings and traffic signs. In addition to the driving simulator, eye tracking glasses were used to track eye movement and an electrocardiograph was used to monitor the heart rate and to determine the level of stress during the runs. The results show statistically significant differences (dependent samples t-test) between the two runs concerning driving speed, lateral position of the vehicle, and visual scanning of the environment. The results prove that road markings and traffic signs provide the drivers with timely and relevant information related to the upcoming situation, thus enabling them to adjust their driving accordingly. The results are valuable to road authorities and provide an explicit confirmation of the importance of traffic signalling for the behaviour of young drivers in night-time conditions, and thus for the overall traffic safety.

Examining interactions within the theory of planned behavior in the prediction of intentions to engage in cannabis-related driving behaviors

Objective: As marijuana use becomes more available to college students through increasing legal reform, this paper seeks to examine intentions for driving under the influence of cannabis (DUIC) and riding with a high driver (RWHD) through the lens of the theory of planned behavior (TPB) and assess potential interactions between personal attitudes, subjective norms, perceived behavioral control (PBC), and sex. Participants: Undergraduate college students (N = 311) completed online surveys in September, 2013. Method: Participants self-reported their attitudes toward DUIC, subjective norms, PBC, past DUIC and RWHD, and intentions to DUIC and RWHD. Results: Participants' attitudes toward DUIC, subjective norms, and PBC were strongly associated with intentions to DUIC and RWHD bivariately. In regression models, attitudes and PBC were both positively and significantly related to intentions to DUIC and RWHD. Conclusions: DUIC and RWHD are concerns for college populations. Targeting personal attitudes and perceived behavioral control via interventions may reduce these behaviors.

Differences in alcohol cognitions, consumption, and consequences among first-time DUI offenders who co-use alcohol and marijuana

BACKGROUND

A significant portion of alcohol-related DUI offenders engage in co-use of alcohol and marijuana (AM). Given expanding marijuana legalization and the impaired driving risks associated with co-use, it is of increased importance to understand how characteristics of AM co-users compare to those who use alcohol only (AO) in order to inform DUI interventions and prevent recidivism.

METHODS

Participants were 277 first-time DUI offenders enrolled in a first-time DUI offender program across three locations. Using well-established measures, we evaluated differences in alcohol-related cognitions (positive expectancies and self-efficacy), frequency and quantity of alcohol consumption, and alcohol-related consequences between AO users and AM co-users by running a series of multivariate generalized linear models.

RESULTS

Compared to AO users, AM co-users reported lower self-efficacy to achieve abstinence and avoid DUI. Differences in abstinence self-efficacy largely explain higher relative rates of average and peak drinking quantity and higher odds of binge drinking among AM co-user. Despite lower self-efficacy and higher drinking quantity, there were no significant differences between AM and AO-users on alcohol-related consequences and past month reports of drinking and driving.

CONCLUSIONS

Our results provide preliminary evidence that DUI offenders who co-use alcohol and marijuana have higher alcohol use and lower self-efficacy than AO-users, and long-term consequences for this group should be monitored in future research. DUI programs may screen and identify co-users and consider tailoring their interventions to build self-efficacy to address the risks associated with AM co-use uniquely.

Self-reported driving under the influence of alcohol and cannabis among Ontario students: Associations with graduated licensing, risk taking, and substance abuse

OBJECTIVE

This article describes the patterns of self-reported driving under the influence of alcohol (DUIA) and driving under the influence of cannabis (DUIC) among licensed Ontario students in 2009 and examines their associations with graduated licensing, risk taking, and substance use problems for understanding DUIA and DUIC behaviors. Ontario's graduated licensing system requires new drivers to hold a G1 license for a minimum of 8 months and a G2 license for a minimum of 12 months before a full and unrestricted G license can be obtained. Among other restrictions, G1 drivers must maintain a 0 blood alcohol content (BAC), have an experienced driver in the passenger seat, not drive on any high-speed expressways, and not drive between the hours of midnight and 5 a.m. A G2 license is more similar to a G license, with fewer restrictions.

METHOD

This study analyzed data from the 2009 Ontario Student Drug Use and Health Survey (OSDUHS). The OSDUHS is a biennial population-based survey of students (grades 7 to 12) in Ontario, Canada.

RESULTS

The results showed that 16.3% of licensed students in Ontario reported DUIC and 11.5% reported DUIA during the past year. After controlling for the effect of age, type of license emerged as a robust predictor for both DUIA and DUIC behavior, because students with a G2 and full license were significantly more likely to report DUIA and DUIC than drivers with a G1 license. Multivariate analyses suggested that risk-seeking behaviors were more important for understanding DUIA behavior than for DUIC behavior. Elevated problem indicators for alcohol and for cannabis were associated with DUIA and DUIC, respectively.

CONCLUSIONS

Though much attention has been paid to drinking and driving among adolescents, this research shows that more Ontario students now report driving after cannabis use than after drinking alcohol. The results identify important correlates of both behaviors that may be useful for prevention purposes.

Associations of repeated high alcohol use with unsafe driving behaviors, traffic offenses, and traffic crashes among young drivers: Findings from the New Zealand Drivers Study

OBJECTIVE

The objective of this study was to describe self-reported high alcohol use at each of the 3 licensing stages of graduated driver licensing and its relationship to drink-driving behaviors, intentional risky driving, aggressive driving, alcohol traffic offenses, non-alcohol traffic offenses, and traffic crashes.

METHODS

The New Zealand Drivers Study (NZDS) is a multistage, prospective cohort study of newly licensed drivers interviewed at all 3 stages of the graduated driver licensing system: learner (baseline), restricted (intermediate), and full license. At each stage, alcohol use was self-reported using the Alcohol Use Disorders Identification Test (AUDIT-C), with high alcohol use defined as a score of ≥4 for males and ≥3 for females. Sociodemographic and personality data were obtained at the baseline interview. Alcohol-related, intentional risky, and aggressive driving behaviors were self-reported following each license stage. Traffic crashes and offenses were identified from police records. Crashes were also self-reported.

RESULTS

Twenty-six percent (n = 397) reported no high alcohol use, 22% at one license stage, 30% at 2 stages, and 22% at 3 stages. Poisson regression results (unadjusted and adjusted) showed that the number of stages where high alcohol use was reported was significantly associated with each of the outcomes. For most outcomes, and especially the alcohol-involved outcomes, the relative risk increased with the number of stages of high alcohol use.

CONCLUSIONS

We found that high alcohol use was common among young newly licensed drivers and those who repeatedly reported high alcohol use were at a significantly higher risk of unsafe driving behaviors. Recently introduced zero blood alcohol concentration (BAC) should help to address this problem, but other strategies are required to target persistent offenders.

Analysis of risk factors affecting driver injury and crash injury with drivers under the influence of alcohol (DUI) and non-DUI

OBJECTIVE

The objective of this research was to study risk factors that significantly influence the severity of crashes for drivers both under and not under the influence of alcohol.

METHODS

Ordinal logistic regression was applied to analyze a crash data set involving drivers under and not under the influence of alcohol in China from January 2011 to December 2014.

RESULTS

Four risk factors were found to be significantly associated with the severity of driver injury, including crash partner and intersection type. Age group was found to be significantly associated with the severity of crashes involving drivers under the influence of alcohol. Crash partner, intersection type, lighting conditions, gender, and time of day were found to be significantly associated with severe driver injuries, the last of which was also significantly associated with severe crashes involving drivers not under the influence of alcohol.

CONCLUSIONS

This study found that pedestrian involvement decreases the odds of severe driver injury when a driver is under the influence of alcohol, with a relative risk of 0.05 compared to the vehicle-to-vehicle group. The odds of severe driver injury at T-intersections were higher than those for traveling along straight roads. Age was shown to be an important factor, with drivers 50-60 years of age having higher odds of being involved in severe crashes compared to 20- to 30-year-olds when the driver was under the influence of alcohol. When the driver was not under the influence of alcohol, drivers suffered more severe injuries between midnight and early morning compared to early nighttime. The vehicle-to-motorcycle and vehicle-to-pedestrian groups experienced less severe driver injuries, and vehicle collisions with fixed objects exhibited higher odds of severe driver injury than did vehicle-to-vehicle impacts. The odds of severe driver injury at cross intersections were 0.29 compared to travel along straight roads. The odds of severe driver injury when street lighting was not available at night were 3.20 compared to daylight. The study indicated that female drivers are more likely to experience severe injury than male drivers when not under the influence of alcohol. Crashes between midnight and early morning exhibited higher odds of severe injury compared to those occurring at other times of day. The identification of risk factors and a discussion on the odds ratio between levels of the impact of the driver injury and crash severity may benefit road safety stakeholders when developing initiatives to reduce the severity of crashes.

Characteristics and predictors of recidivist drink-drivers

OBJECTIVE

The current study compared characteristics of nonrecidivist versus recidivist drink-drivers and of recidivists in their first versus second appearance at Back on Track (BOT), the remedial measures program for impaired drivers in Ontario, Canada.

METHODS

Information from 59,134 convicted drivers who participated in BOT between 2000 and 2010 was examined to identify drivers who completed the program a second time following reconviction.

RESULTS

A total of 586 recidivists were identified. Compared to nonrecidivist drivers, recidivists at first attendance were more likely to be male and had higher scores on measures of alcohol dependence and adverse legal consequences of substance use. Compared to nonrecidivist drivers, recidivists at second attendance were significantly older, had a higher income, were more likely to be retired, and were less likely to be employed part-time. They had fewer legal problems. Recidivists reported fewer drinking days and fewer drinks per occasion but greater use of benzodiazepines than nonrecidivists and had higher scores on a measure of future risk of alcohol- and drug-related problems. Comparison of recidivists' characteristics at first versus second attendance confirmed many of these findings, with second-time recidivists reporting fewer drinks per drinking day and greater use of benzodiazepines and having higher scores on a measure of future substance use problems than first-time recidivists.

CONCLUSIONS

Results suggest that identification of drivers at increased risk of recidivism may be possible at first program attendance by examining indicators of increased alcohol-related problems. In addition, recidivists appear to show a greater readiness to change at second attendance. Implications for remedial program development and recommendations for future research are discussed.

The effects of cannabis intoxication on motor vehicle collision revisited and revised

AIMS

To determine whether and to what extent acute cannabis intoxication increases motor vehicle crash risk.

DESIGN

Study 1 replicates two published meta-analyses, correcting for methodological shortcomings. Study 2 is an updated meta-analysis using 28 estimates from 21 observational studies. These included studies from three earlier reviews, supplemented by results from a structured search in Web of Science and Google Scholar, and by the personal libraries of the research team. Risk estimates were combined using random-effects models and meta-regression techniques.

SETTING

Study 1 replicates the analysis of Asbridge et al., based on nine studies from five countries, published 1982-2007; and Li et al., based on nine studies from six countries, published 2001-10. Study 2 involves studies from 13 countries published in the period 1982-2015.

PARTICIPANTS

In study 1, total counts extracted totalled 50 877 (27 967 cases, 22 910 controls) for Asbridge et al. and 93 229 (4236 cases and 88 993 controls) for Li et al. Study 2 used confounder-adjusted estimates where available (combined sample size of 222 511) and crude counts from the remainder (17 228 total counts), giving a combined sample count of 239 739.

MEASUREMENTS

Odds ratios (OR) were used from case-control studies and adjusted OR analogues from culpability studies. The impact of the substantial variation in confounder adjustment was explored in subsample analyses.

FINDINGS

Study 1 substantially revises previous risk estimates downwards, with both the originally reported point estimates lying outside the revised confidence interval. Revised estimates were similar to those of study 2, which found cannabis-impaired driving associated with a statistically significant risk increase of low-to-moderate magnitude [random-effects model OR 1.36 (1.15-1.61), meta-regression OR 1.22 (1.1-1.36)]. Subsample analyses found higher OR estimates for case-control studies, low study quality, limited control of confounders, medium-quality use data and not controlling for alcohol intoxication.

CONCLUSIONS

Acute cannabis intoxication is associated with a statistically significant increase in motor vehicle crash risk. The increase is of low to medium magnitude. Remaining selection effects in the studies used may limit causal interpretation of the pooled estimates.

Factors affecting stability and change in risky driving from late adolescence to the late twenties

The risky driving tendencies of young drivers has been extensively researched, but much less is known about across-time patterns of risky driving behavior and the factors which influence these. This study identified factors associated with stable, increasing and decreasing risky driving trajectories among 751 Australian drivers participating in an ongoing longitudinal study. Five groups were formed on the basis of participants' patterns of risky driving from 19-20 to 27-28 years (i.e., stable low-risk, stable speeding, stable high-risk, increasing and decreasing). Very few participants exhibited a stable high-risk pattern. Characteristics that differentiated the different across-time groups were identified using Multinomial Logistic Regression. The most consistent correlates of risky driving patterns were antisocial behavior, binge drinking and relationship status. Sex, school completion, temperament, civic engagement, and antisocial peer friendships were also correlated with different across-time patterns. The implications of these findings for road safety are discussed.

Severity of urban cycling injuries and the relationship with personal, trip, route and crash characteristics: analyses using four severity metrics

OBJECTIVE

To examine the relationship between cycling injury severity and personal, trip, route and crash characteristics.

METHODS

Data from a previous study of injury risk, conducted in Toronto and Vancouver, Canada, were used to classify injury severity using four metrics: (1) did not continue trip by bike; (2) transported to hospital by ambulance; (3) admitted to hospital; and (4) Canadian Triage and Acuity Scale (CTAS). Multiple logistic regression was used to examine associations with personal, trip, route and crash characteristics.

RESULTS

Of 683 adults injured while cycling, 528 did not continue their trip by bike, 251 were transported by ambulance and 60 were admitted to hospital for further treatment. Treatment urgencies included 75 as CTAS=1 or 2 (most medically urgent), 284 as CTAS=3, and 320 as CTAS=4 or 5 (least medically urgent). Older age and collision with a motor vehicle were consistently associated with increased severity in all four metrics and statistically significant in three each (both variables with ambulance transport and CTAS; age with hospital admission; and motor vehicle collision with did not continue by bike). Other factors were consistently associated with more severe injuries, but statistically significant in one metric each: downhill grades; higher motor vehicle speeds; sidewalks (these significant for ambulance transport); multiuse paths and local streets (both significant for hospital admission).

CONCLUSIONS

In two of Canada's largest cities, about one-third of the bicycle crashes were collisions with motor vehicles and the resulting injuries were more severe than in other crash circumstances, underscoring the importance of separating cyclists from motor vehicle traffic. Our results also suggest that bicycling injury severity and injury risk would be reduced on facilities that minimise slopes, have lower vehicle speeds, and that are designed for bicycling rather than shared with pedestrians.

Potential determinants of drink driving in young adults

OBJECTIVE

The main purposes of this study were to examine the usefulness of the variables of the theory of planned behavior (viz. attitudes, social norms, and self-efficacy) and to explore the relationship between optimism bias and drink driving in young adults. In addition, we explored gender differences in drink driving with provision for the effect of variables such as driving frequency and alcohol consumption.

METHODS

Data were collected via a questionnaire administered to 274 drivers (59.9% females) aged 18-30 years (24.36 ± 2.96).

RESULTS

The results obtained with provision for driving frequency revealed substantial differences in driving behaviors between genders. Thus, males were more prone to drink driving, perceived less disapproval by their significant others (parents and peers), and felt less able to avoid drinking-and-driving situations. In addition, they self-reported more frequent alcohol consumption and driving under the influence. The results also confirm the significance of peers' subjective norms and attitudes to drink driving in males. Overconfidence in their own driving skills for driving drunk and perceived behavioral control were found to be significant predictors for drink driving in females. Optimism bias also played a slightly significant role in predicting drink driving but only in females.

CONCLUSIONS

The important practical implications of these results with a view to designing effective interventions to prevent the risks associated with drink driving in the young population are discussed. Interventions should focus on young people's perceptions of group norms and promoting cautionary driving choices and alternatives to drink driving.

Driving under the influence among frequent ecstasy consumers in Australia: trends over time and the role of risk perceptions

BACKGROUND

Driving under the influence (DUI) of alcohol and illicit drugs is a serious road safety concern. This research aimed to examine trends in DUI across time and changes in attitudes towards the risks (crash and legal) associated with DUI among regular ecstasy users (REU) interviewed in Australia.

METHODS

Participants were regular (at least monthly) ecstasy users surveyed in 2007 (n=573) or 2011 (n=429) who had driven a car in the last six months. Face to face interviews comprised questions about recent engagement of DUI and roadside breath (alcohol) and saliva (drug) testing. Participants also reported the risk of crash and of being apprehended by police if DUI of alcohol, cannabis, ecstasy, and methamphetamine.

RESULTS

There were significant reductions in DUI of psychostimulants (ecstasy, methamphetamine, cocaine, LSD) but not alcohol or cannabis between 2007 and 2011. This was accompanied by increased experience of roadside saliva testing and increases in crash and legal risk perceptions for ecstasy and methamphetamine, but not alcohol or cannabis. When the relationship between DUI and risk variables was examined, low crash risk perceptions were associated with DUI of all substances and low legal risk perceptions were associated with DUI of ecstasy.

CONCLUSIONS

The observed reduction in DUI of psychostimulants among frequent ecstasy consumers may be related to increased risk awareness stemming from educational campaigns and the introduction of saliva testing on Australian roads. Such countermeasures may be less effective in relation to deterring or changing attitudes towards DUI of cannabis and alcohol among this group.

Mixed logit model-based driver injury severity investigations in single- and multi-vehicle crashes on rural two-lane highways

Crashes occurring on rural two-lane highways are more likely to result in severe driver incapacitating injuries and fatalities. In this study, mixed logit models are developed to analyze driver injury severities in single-vehicle (SV) and multi-vehicle (MV) crashes on rural two-lane highways in New Mexico from 2010 to 2011. A series of significant contributing factors in terms of driver behavior, weather conditions, environmental characteristics, roadway geometric features and traffic compositions, are identified and their impacts on injury severities are quantified for these two types of crashes, respectively. Elasticity analyses and transferability tests were conducted to better understand the models' specification and generality. The research findings indicate that there are significant differences in causal attributes determining driver injury severities between SV and MV crashes. For example, more severe driver injuries and fatalities can be observed in MV crashes when motorcycles or trucks are involved. Dark lighting conditions and dusty weather conditions are found to significantly increase MV crash injury severities. However, SV crashes demonstrate different characteristics influencing driver injury severities. For example, the probability of having severe injury outcomes is higher when vans are identified in SV crashes. Drivers' overtaking actions will significantly increase SV crash injury severities. Although some common attributes, such as alcohol impaired driving, are significant in both SV and MV crash severity models, their effects on different injury outcomes vary substantially. This study provides a better understanding of similarities and differences in significant contributing factors and their impacts on driver injury severities between SV and MV crashes on rural two-lane highways. It is also helpful to develop cost-effective solutions or appropriate injury prevention strategies for rural SV and MV crashes.

Factors Contributing to Crashes among Young Drivers

Young drivers are the group of drivers most likely to crash. There are a number of factors that contribute to the high crash risk experienced by these drivers. While some of these factors are intrinsic to the young driver, such as their age, gender or driving skill, others relate to social factors and when and how often they drive. This article reviews the factors that affect the risk of young drivers crashing to enable a fuller understanding of why this risk is so high in order to assist in developing effective countermeasures.

Analysis of factors associated with injury severity in crashes involving young New Zealand drivers

Young people are a risk to themselves and other road users, as motor vehicle crashes are the leading cause of their death. A thorough understanding of the most important factors associated with injury severity in crashes involving young drivers is important for designing well-targeted restrictive measures within youth-oriented road safety programs. The current study estimates discrete choice models of injury severity of crashes involving young drivers conditional on these crashes having occurred. The analysis examined a comprehensive set of single-vehicle and two-vehicle crashes involving at least one 15-24 year-old driver in New Zealand between 2002 and 2011 that resulted in minor, serious or fatal injuries. A mixed logit model accounting for heterogeneity and heteroscedasticity in the propensity to injury severity outcomes and for correlation between serious and fatal injuries proved a better fit than a binary and a generalized ordered logit. Results show that the young drivers' behavior, the presence of passengers and the involvement of vulnerable road users were the most relevant factors associated with higher injury severity in both single-vehicle and two-vehicle crashes. Seatbelt non-use, inexperience and alcohol use were the deadliest behavioral factors in single-vehicle crashes, while fatigue, reckless driving and seatbelt non-use were the deadliest factors in two-vehicle crashes. The presence of passengers in the young drivers' vehicle, and in particular a combination of males and females, dramatically increased the probability of serious and fatal injuries. The involvement of vulnerable road users, in particular on rural highways and open roads, considerably amplified the probability of higher crash injury severity.

Have drivers at alcohol outlets changed their behavior after the new traffic law?

OBJECTIVE

In an attempt to reduce high levels of traffic crashes, a new legislation was approved in Brazil in 2008. This study aimed to assess behavioral change among drivers who had drunk at alcohol outlets (AO) after implementation of the law.

METHOD

A three-stage probability sampling survey was conducted in Porto Alegre, state of Rio Grande do Sul, Brazil. Individuals seen leaving AOs after drinking were approached (n=3,018). Selected drivers (n=683) answered a structured interview, were breathalyzed, and had saliva specimens collected for drug screening.

RESULTS

Overall, 60.3% (SE 4.5) of drivers reported they did not change their behavior. Among those who reported behavioral changes, most reported drinking less as their main strategy toward safer driving behavior. Variables independently associated with behavior change included having drunk at a high outlet density area (odds ratio [OR] 1.7 [1.1-2.8]) and having a favorable opinion about the law (OR 4.3 [2.1-8.9]).

CONCLUSIONS

Our findings suggest that awareness of the law has not been enough to promote behavioral change. As most drivers had a favorable opinion of the law and this variable was found to be the strongest predictor of behavior change, efforts to better integrate education and enforcement seem to be pivotal and might be well received by the population.

Spatial-temporal analysis of drink-driving patterns in Hong Kong

Normally, bars and restaurants are the preferred locations for drinking. Therefore, there is concern that the roads in bar and restaurant areas could have a higher probability of drink-drivers and alcohol-related road crashes. Many studies have been conducted to model the association between drinking locations and the prevalence of drink-driving, so that cost-effective enforcement strategies can be developed to combat drink-driving. In this study, a cluster analysis approach was applied to model the spatial-temporal variation of drink-driving distribution in Hong Kong. Six spatial-temporal clusters of drink-driving distribution emerged from the data: (i) bar and restaurant area, weekend-overnight; (ii) bar and restaurant area, other timespan; (iii) urban area, weekend-overnight; (iv) urban area, other timespans; (v) rural area, weekend-overnight; and (vi) rural area, other timespans. Next, separate zero-inflated regression models were established to identify the factors contributing to the prevalence of drink-driving for each of the six recognized clusters. The results indicated that drivers in rural areas tend to consume more alcohol than those in urban areas, regardless of the time period. In addition, both seasonal variation and vehicle class were found to determine the breath alcohol concentration (BrAC) levels among drivers.

Attitudes do matter: The role of attitudes and personality in DUI offenders

Several studies have related personality variables with antisocial behavior. Among antisocial behaviors, driving under the influence (DUI) has received growing attention in recent years, particularly in relation to the role of personality. However, it has been shown that personality alone is not sufficient to accurately predict DUI. As a result, there is growing interest in identifying other types of individual differences that might predict this behavior better, such as attitudinal variables. The aim of this study was to examine differences in personality dimensions and attitudes between a group of DUI offenders and a comparison group. Ninety-eight subjects were assessed: 51 subjects who had been convicted of a DUI offense following a diversion program, and 47 drivers without criminal records. Personality was measured with the NEO-Five Factor Inventory (NEO-FFI) and antisocial attitudes were assessed with the Jesness Inventory-Revised. Results indicated that offenders were more prone to show antisocial attitudes (p<.001) than comparisons. In terms of personality, there were no significant differences between the two groups. These findings suggest that attitudes may be useful predictors of DUI and should be taken into account in interventions designed to avoid recidivism.

Evaluation of the Mental Healthiness Aging Initiative: community program to promote awareness about mental health and aging issues

The objective of this study is to evaluate the Mental Healthiness Aging Initiative, designed to promote community awareness and knowledge about mental health and aging issues. This study occurred during 2007-2009 in 67 of 120 counties in Kentucky. A rural region (11 counties) received the intervention, consisting of focus groups, Extension Agent training, and television-based social marketing campaign. Partial-intervention counties (29 counties) received only the television-based social marketing campaign. The control counties (27 counties) received no intervention activities. Results indicated that the intervention counties agreed more with being able to assist elder adults with a potential mental illness. Also, the intervention counties understood the risk of consuming alcohol and medications better, but had a poorer recognition of drinking problems in elder adults. These findings need to be considered within study limitations, such as measurement error, degree of intervention exposure, and regional differences across intervention groups. The study demonstrates that community interventions on mental health awareness and knowledge are feasible within majority rural regions, with Extension Agents being gatekeepers, for promoting positive messages about mental health and aging issues.

Decision-making capacities and affective reward anticipation in DWI recidivists compared to non-offenders: a preliminary study

OBJECTIVES

Impaired decision making is seen in several problem behaviours including alcoholism and problem gambling. Decision-making style may contribute to driving while impaired with alcohol (DWI) in some offenders as well. The Somatic Marker Framework theorizes that decision making is the product of two interacting affective neural systems, an impulsive, rapid, amygdala-dependent process for emotionally signalling the immediate negative or positive consequences of an option, and a reflective, longer-lasting, ventral medial prefrontal cortex dependent system for emotionally signalling the future negative or positive prospects of an option. This study tested the hypothesis that offenders who showed disadvantageous decision-making would be at higher risk for recidivism than those who showed more advantageous decision-making. In addition, in line with the Somatic Marker Hypothesis, offenders who showed disadvantageous decision-making would exhibit a distinct pattern of somatic activation compared to offenders who showed more advantageous decision-making.

METHODS

A sample of 21 DWI offenders with from 2 to 7 past DWI convictions and a reference group consisting of 19 non-offender (N-O) drivers were recruited and administered the Iowa Gambling Task (IGT), as well as evaluated on sociodemographic, driving and alcohol use dimensions. In addition, anticipatory skin conductance response (aSCR) was measured in the 5s prior to each of a 100 card draws on the IGT.

RESULTS

Median split of the DWI offender sample based upon overall performance on the IGT yielded two subgroups (IGT-R Hi and IGT-R Lo). Hypothesis 1 was supported, as the IGT-R Lo group possessed significantly greater frequency of past DWI convictions and severity of past drinking. Descriptive analyses revealed that on the IGT, IGT-R Hi group performed similarly to the N-O reference group while the IGT-R Lo group performed significantly worse. Hypothesis 2 was not supported.

CONCLUSIONS

Decision making is a plausible explanatory neurocognitive pathway to severer forms of DWI. The role of emotional processing in DWI risk is uncertain. Subtyping DWI offenders using neurocognitive criteria seems a promising avenue for improving clinically meaningful methods of DWI risk assessment and intervention.

Emotional abilities as predictors of risky driving behavior among a cohort of middle aged drivers

The aim of this study is to analyze the relationship between emotional abilities and the influence of this relationship on self reported drivers' risky attitudes. The risky driving attitudes and emotional abilities of 177 future driving instructors were measured. The results demonstrate that risky attitudes correlate negatively with emotional abilities. Regression analysis showed that adaptability and interpersonal abilities explained the differences observed in the global risk attitude index. There were some differences in the specific risk factors. The variability observed in the speed and distraction and fatigue factors could also be explained by interpersonal and adaptability abilities. Nevertheless the tendency to take risks was explained by stress management and also interpersonal components. Emotional abilities have the weakest relation with alcohol and drugs factor, and in this case the variability observed was explained by the adaptability component. The results obtained highlight the importance take off including emotional abilities in prevention programs to reduce risky driving behaviors.

Does gender moderate the relationship between driver aggression and its risk factors?

AIM

The current study assessed gender as a potential moderator of the relationship between self-reported driver aggression and various demographic variables, general and driving-related risk factors.

METHODS

Using data from a general-population telephone survey conducted from July 2002 through June 2005, two approaches to binary logistic regression were adopted. Based on the full dataset (n=6259), the initial analysis was a hierarchical-entry regression examining self-reported driver aggression in the last 12 months. All demographic variables (i.e., gender, age, income, education, marital status), general risk factors (i.e., psychological distress, binge drinking, cannabis use), and driving-related risk factors (i.e., driving exposure, stressful driving, exposure to busy roads, driving after drinking, driving after cannabis use) were entered in the first block, and all two-way interactions with gender were entered stepwise in the second block. The subsequent analysis involved dividing the sample by gender and conducting logistic regressions with main effects only for males (n=2921) and females (n=3338) separately.

RESULTS

Although the prevalence of driver aggression in the current sample was slightly higher among males (38.5%) than females (32.9%), the difference was small, and gender did not enter as a significant predictor of driver aggression in the overall logistic regression. In that analysis, difficulty with social functioning and being older were associated with a reduced risk of driver aggression. Marital status and education were unrelated to aggression, and all other variables were associated with an increased risk of aggression. Gender was found to moderate the relationships between driver aggression and only three variables: income, psychological distress, and driving exposure. Separate analyses on the male and female sub-samples also found differences in the predictive value of income and driving exposure; however, the difference for psychological distress could not be detected using this separate regression approach. The secondary analysis also identified slight differences in the predictive value of four of the risk factors, where the odds ratios for both males and females were in the same direction but only one of the two was statistically significant.

CONCLUSIONS

The results demonstrate the importance of conducting the gender analysis using both regression approaches. With few exceptions, factors that were predictive of driver aggression were generally the same for both male and female drivers.

Substance-related traffic-risk behaviors among college students

AIMS

Drunk driving is a major public health concern, but drugged driving has received little attention. This study examines drugged driving and riding with a drugged driver in a college student sample, in terms of prevalence, age-related trends, race/sex differences, overlap with drunk driving, and risk for alcohol and marijuana dependence.

METHODS

Students (N=1194) ages 19-22 were interviewed annually for 3 years about past-year frequency of drugged driving, riding with a drugged/drunk driver, drunk driving, access to a car, and alcohol/drug dependence. Annual follow-up rates were excellent (88-91%). Repeated measures analyses were conducted using generalized estimating equations (GEE).

RESULTS

One in six (17%(wt)) 19-year-olds with access to a car drove drugged in the past year; prevalence remained stable through age 22. Drugged driving was more prevalent among males (p<.001) and whites (p<.01). Riding with a drugged driver varied by race and sex (overall prevalence 28%(wt) at age 19), was stable from age 19 to 21, and decreased by age 22 (p<.05). Annually, half of drugged drivers also drove drunk (ranges between 47% and 60%). Both drugged and drunk driving were independently associated with increased risk for alcohol dependence, holding constant age, sex, and race. Drunk driving did not add to the risk for marijuana dependence in the context of drugged driving.

CONCLUSIONS

The prevalence of drugged driving is similar to drunk driving among college students. Both are strongly associated with underlying alcohol and drug dependence. Prevention and treatment implications are discussed.

Predictors of driving after alcohol and drug use among adolescents in Valencia (Spain)

BACKGROUND

Driving under the influence of alcohol and drugs has been identified as a risk factor for road traffic crashes. We have assessed the prevalence and predictor factors for driving after alcohol and drug use by adolescents.

METHODS

A cross-sectional survey involving 11,239 students aged 14-18 years from 252 private and public schools in the Valencia region of Spain was conducted. The prevalence and predictors of driving after alcohol use, alcohol and drug use, or drug use during the previous 6 months were measured.

RESULTS

Of the students who reported driving (20%), 45.1% indicated driving after alcohol and drug use. The consumption of various drugs was higher among students who drove a vehicle compared with those who did not. The likelihood of driving after consuming alcohol, or alcohol and drugs, increased in line with the number of standard drink units per week, reports of any lifetime alcohol- or drug-related problems, and poor family relationship. In addition, masculine gender and early alcohol use increased the likelihood of driving after consuming alcohol.

CONCLUSIONS

Driving after alcohol and drug use is quite prevalent among adolescents in the Valencia region of Spain. There is a need for implementation of targeted policies for adolescents. This should focus on education and information on alcohol/drug use and driving.

Personality traits and mental health of severe drunk drivers in Sweden

The present study was intended to investigate personality characteristics and mental health of severe driving under influence (DUI) offenders in a Swedish cohort. More specifically the aim was to investigate the personality traits as assessed by The NEO personality inventory (NEO-PI-R) and aspects of mental health as assessed by the symptom checklist (SCL-90) as compared to the general population. The subjects were 162 severe DUI offenders (with the BAC >0.099%) with an age range of 18-88 years, 143 males and 19 females. It was found that the openness to experience and conscientiousness scales of NEO-PI-R differentiated Swedish DUI offenders from Swedish norm population. The differences between the DUI group and the general population on the on SCL-90 scales were all significant except on the Hostility scale. Two main subtypes of DUI offenders identified were roughly comparable to types I and II alcoholics, as in Cloninger's typology. Among all the scales used (personality traits, psychiatric comorbidity and alcohol use), the only factor that was predictive for future relapses to drunk driving was the factor of depression.

Too young to drink but old enough to drive under the influence: a study of underage offenders as seen in substance abuse treatment in Texas

Driving under the influence (DUI) is a major road safety problem. Historically, alcohol has been assumed to play a larger role in crashes and DUI education programs have reflected this assumption, although recent evidence suggests that younger drivers are becoming more likely to drive drugged than to drive drunk. This is a study of 7096 Texas clients under age 21 who were admitted to state-funded treatment programs between 1997 and 2007 with a past-year DUI arrest, DUI probation, or DUI referral. Data were obtained from the State's administrative dataset. Multivariate logistic regressions models were used to understand the differences between those minors entering treatment as a DUI as compared to a non-DUI as well as the risks for completing treatment and for being abstinent in the month prior to follow-up. A major finding was that over time, the primary problem for underage DUI drivers changed from alcohol to marijuana. Being abstinent in the month prior to discharge, having a primary problem with alcohol rather than another drug, and having more family involved were the strongest predictors of treatment completion. Living in a household where the client was exposed to alcohol abuse or drug use, having been in residential treatment, and having more drug and alcohol and family problems were the strongest predictors of not being abstinent at follow-up. As a result, there is a need to direct more attention towards meeting the needs of the young DUI population through programs that address drug as well as alcohol consumption problems.

Which young people accept a lift from a drunk or drugged driver?

INTRODUCTION

Riding with a drunk and/or a drugged driver (RDD) is a risk behaviour that has received very little attention in spite of its potential dangers. Young people involved in the recreational nightlife context are especially at risk.

METHOD

1363 regular users of recreational nightlife from nine European countries (mean age: 21.75; 51.5% women) filled out a self-administered and anonymous questionnaire (in 2006).

RESULTS

37.2% had practised RDD during the previous month. RDD is related to drunkenness and use of drugs, personality factors such as impulsivity, preferring to use a private car to get to nightlife venues, living in a southern European country and being unemployed. No significant influence was found for age, gender, educational level or socioeconomic status.

DISCUSSION

It is important to raise awareness about the high prevalence of RDD. This lack of awareness can be related to its social acceptance among young people. The use of private cars for going to nightlife venues should be discouraged.

Driving under the influence of cannabis: links with dangerous driving, psychological predictors, and accident involvement

Driving under the influence of cannabis (DUIC) has become a growing concern. Studies investigating the impact of DUIC on traffic safety have shown evidence that, during the acute period of cannabis intoxication, cannabis diminishes driving faculties and is associated with an elevated risk of collision. However, DUIC drivers seem to exhibit a general reckless driving style that may contribute to an over-estimation of DUIC-related collisions among this group. In this study, we investigated DUIC drivers with respect to self-reported dangerous driving habits (e.g., risky driving, aggressive driving and negative emotional driving), behaviours observed in a driving simulator, psychological predictors and crash involvement. Results suggest that DUIC is associated with self-reported and observed risky driving and negative emotional driving. We also found that sensation seeking and impulsivity are independent psychological predictors of DUIC. Finally, a trend suggests that self-reported DUIC is associated with an increased risk of being involved in a car accident, after controlling for dangerous driving and demographic variables. Implications for interventions are discussed.

Factors associated with driving under the influence of alcohol and drugs among an Australian sample of regular ecstasy users

The aim of the present study was to investigate factors associated with driving under the influence (DUI) of alcohol and other drugs (ecstasy, cannabis and methamphetamine) among a group of regular ecstasy users. Participants were those who participated in the Australian Ecstasy and related Drug Reporting System (EDRS) in 2007 and had recently driven a motor vehicle (n=573). Participants were administered a semi-structured face-to-face interview which included questions about ecstasy and other drug use, associated health-related issues, and risk behaviours. Close to half of those who were current consumers of ecstasy, cannabis, and methamphetamine had recently driven under the influence of these drugs, while two-fifths of current alcohol users reported recent drink driving. Frequency of use for each substance was the most significant correlate of DUI of alcohol, cannabis, and methamphetamine, suggesting that interventions targeting high frequency and problematic drug use may be useful in reducing the occurrence of DUI for these substances. Low perception of the likelihood of having an accident was the most significant correlate of DUI of ecstasy and also related significantly to DUI of other substances. Perceptions of low likelihood of being apprehended by police and demographic characteristics such as younger age and male sex were also weakly associated with DUI. Together these findings have important implications for targeted interventions aimed at reducing the occurrence of DUI among regular drug users.

Criminal and alcohol problems among Swedish drunk drivers--predictors of DUI relapse

The prevalence and types of crime offences, as well as predictors of relapse, among drivers suspected of driving under influence (DUI) were investigated. A total of 1830 Swedish DUI drivers responded to the Alcohol Use Disorders Identification Test--AUDIT. Information about previous DUI offences, other traffic offences along with other types of criminal offences was taken from a crime register. A total criminality (including all traffic offences) of 64% in the period of five years before investigation was analyzed. 40% of the sample had other criminality besides traffic violations during that period. 14.3% of the drivers relapsed to DUI in the two-year period after the investigation. In terms of DUI relapse, the following factors were the main predictors: previous traffic violations, previous DUI offences, previous other criminality (frauds or other acts of dishonesty) and detection hours between 12.00 and 19.00. Detection in general traffic controls and high BAC (blood alcohol concentration) when detected were the strongest factors with negative correlation to DUI re-offence.

A longitudinal examination of the relationship between adolescent problem behaviors and traffic crash involvement during young adulthood

Previous research examining the relationship between adolescent problem behaviors and young adult traffic outcomes (crashes, convictions, risky driving) has produced differing results. Possible reasons for this may be the heterogeneity of the crash outcomes (from minor fender-benders to fatal crashes), the gender of the driver, and/or the age of the driver. The aim of this research was to investigate the relationship between adolescent problem behaviors and young adult crashes to determine the extent to which the above factors influenced this relationship. This study was part of the Dunedin Multidisciplinary Health and Development Study (DMHDS), which is a longitudinal study of a cohort (n = 1,037) born in Dunedin, New Zealand, from April 1972 to March 1973. This cohort has been followed up regularly since birth, and the data for the present research were obtained at the 18-, 21-, and 26-year-old follow-up interviews. The problem behaviors examined were those identified by Jessor in the theory of problem behavior, namely, tobacco smoking, marijuana use, alcohol use, delinquent behavior, and unsafe sexual behavior. Data for these measures were obtained in personal interviews when the cohort was aged 18 years. The self-reported crash data were obtained at the age 21 and age 26 follow-up interviews. Driving exposure, academic qualifications, employment, being a parent, and marital status were included as potential confounders. The results show that involvement in adolescent problem behaviors predicted crash involvement at age 21 for the females but not the males and at age 26 for the males but not the females. Possible explanations for these differences by age and gender are discussed.

Drink driving and the patterns and context of drinking among New Zealand adolescents

AIM

To examine the association between drink driving and the patterns and locations of usual drinking among New Zealand adolescents.

METHODS

This is a secondary analysis of data from a nationally representative youth health survey, the sampling frame for which was all New Zealand secondary schools with more than 50 students enrolled in years 9 to 13 (ages 12 to 18 years) in 2001. The analysis was restricted to the 3408 survey respondents aged 15 years or older who were current drinkers and drivers.

RESULTS

In total, 17.3% of participants reported drink driving in the previous month. Drink driving was significantly associated with frequent (at least weekly) alcohol use, binge drinking and usually drinking away from home, that is in cars, outdoors, at bars or nightclubs, at parties, at school and at work. Students' perception that parents and schools care about them, parental monitoring, and high academic achievement was associated with a reduced risk of drink driving while having friends who drink alcohol increased this risk. These associations were similar among boys and girls.

CONCLUSION

The findings support calls to address how and where young people drink, and indicate the potential gains to be made with family- and school-based interventions.

Socio-economic status and problem alcohol use: the positive relationship between income and the DSM-IV alcohol abuse diagnosis

AIMS

Epidemiological evidence indicates a positive relationship between income and the prevalence of alcohol abuse in the general population, but an inverse relationship between income and alcohol dependence. Among those with a diagnosis of alcohol abuse, the most prevalent criterion is hazardous use, which commonly requires sufficient resources to own or access a car. The present study investigated whether the association between income and the prevalence of current alcohol abuse is accounted for by the hazardous use criterion; specifically, the drinking and driving symptoms of the hazardous use criterion.

DESIGN

Face-to-face survey conducted in the 2001-02 National Epidemiologic Survey on Alcohol and Related Conditions, interviewed with the Alcohol Use Disorders and Associated Disabilities Interview 4th edition (AUDADIS-IV).

SETTING

The United States and District of Columbia, including Alaska and Hawaii.

PARTICIPANTS

Household and group-quarters residents aged >18 years. Life-time dependence cases were excluded (n = 4781).

MEASUREMENTS

Income was defined as past-year personal income. Outcomes were specific alcohol abuse criteria and symptom questions. Logistic regressions were performed controlling for demographics. The relationship between alcohol abuse severity indicators and income was modeled using polytomous regression. Findings Among the alcohol abuse criteria, hazardous use is the most prevalent and the only criterion to have a significant positive relationship with income (F = 20.3, df = 3, P < 0.0001). Among the hazardous use symptoms, driving after drinking (F = 13.0, df = 3, P < 0.0001) and driving while drinking (F = 9.2, df = 3, P < 0.0001) were related positively to income.

CONCLUSIONS

Because hazardous use is the most commonly endorsed criterion of alcohol abuse, the link with income raises questions about whether the current alcohol abuse diagnosis can capture the full range of alcohol abusers in every socio-economic class. While many psychiatric disorders exhibit an inverse relationship with socio-economic status, a selection bias may cause the alcohol abuse diagnosis to have an artificially positive relationship with income due to the necessity for access to a vehicle to be diagnosed.

Personality factors as predictors of persistent risky driving behavior and crash involvement among young adults

OBJECTIVES

The aim of this study was to examine the relationship between personality factors assessed during adolescence and persistent risky driving behavior and traffic crash involvement among young adults.

DESIGN

Data for this investigation were drawn from the Dunedin Multidisciplinary Health and Development Study, a longitudinal study of a cohort born in Dunedin, New Zealand.

SUBJECTS

The study population was 1037 young people born between 1 April 1972 and 31 March 1973.

MAIN OUTCOME MEASURES

The main outcome measures were persistent risky driving behaviors and crash involvement, collected in a face-to-face road-safety interview at ages 21 and 26.

RESULTS

The only outcomes for which there were sufficient numbers of females were a driver involved in any crash and a driver involved in an injury crash. Univariate logistic regression revealed that there were no significant predictors for either of these outcomes. For the males, at the univariate level, aggression, traditionalism, and alienation were the personality scales most frequently associated with risky driving behavior and crash risk. After adjusting for driving exposure, only high levels of aggression predicted being a driver involved in a crash, and alienation predicted being a driver involved in an injury crash.

CONCLUSION

These results suggest that road-safety interventions seeking to deter young adult males from persistent risky driving behavior need to be directed at those who do not endorse traditional views, are aggressive, and feel alienated from the rest of society.

Gender differences in DUI offenders in treatment in Texas

OBJECTIVE

This is a study of 8,464 adult women and 21,155 adult males who entered substance abuse treatment in Texas between 2000 and 2005. Participants were either on probation for driving under the influence (DUI), were referred to treatment by DUI probation, or had been arrested for DUI in the past year.

METHODS

The female and male clients were compared on demographic characteristics, substance use patterns, DSM-IV diagnoses, and levels of impairment. T tests and chi square tests were used to determine significance and multivariate logistic regression identified predictors of completing treatment and being abstinent at follow-up.

RESULTS

The proportion of females who were sent to treatment as a result of DUI increased from 27% in 2000 to 32% in 2005. Females were significantly more likely than males to be White (73% vs. 56%), to have used substances a shorter period of time (17 vs. 19 years), to be seeking custody to regain their children (11% vs. 2%), to meet the DSM criteria for drug dependence (32% vs. 23%), to have injected drugs (31% vs. 23%), to have used substances daily (42% vs. 40%), to have a depressive disorder (16% vs. 7%) or bipolar disorder (12% vs. 5%), and to be have been in treatment before (60% vs. 49%). In contrast, males were more likely to be alcohol dependent (49% vs. 44%). Females were less likely to complete treatment (67% vs. 72%) and reported significantly more days of problems on the 6 domains of the ASI at both admission and at 60-day follow-up. Furthermore, at follow-up, they were more likely to be living with someone who abused alcohol or used drugs (9% vs.7%).

CONCLUSIONS

Although females comprised only 29% of the DUI treatment admissions, they were more impaired and experienced more problems than their male counterparts. The findings indicate that additional resources, including treatment for co-occurring mental health problems and living in sober households, may be keys to helping these women achieve abstinence and prevent additional DUI episodes.

Correlates of driving under the influence of cannabis

BACKGROUND

Identifying cannabis users who are most at risk of driving under the influence of cannabis (DUIC) has important implications for drug treatment and prevention efforts. This paper examined correlates of DUIC among a purposive sample of recent cannabis users.

METHODS

Interviews were carried out among a cross-sectional sample of 320 Australian cannabis users. Past-year prevalence of DUIC (without using alcohol or other drugs) was regressed against a range of potential predictor variables.

RESULTS

Use of multiple drugs, believing that DUIC does not increase accident risk and cannabis dependence all predicted likelihood of DUIC. There was an interaction between age of first cannabis use and gender, whereby earlier onset cannabis use predicted DUIC but only among women.

CONCLUSIONS

The correlates of drug driving reflected cannabis users' beliefs about the dangers of cannabis use as well as their patterns of drug consumption. The emergence of cannabis dependence and age of onset as predictors of DUIC suggests a clearly defined role for treatment and prevention efforts in reducing the potential harms associated with DUIC.

The impact of cannabis on driving

BACKGROUND

Cannabis is known to have detrimental effects on human performance and may also affect driving adversely. However, studies designed to examine this issue have provided equivocal findings. We set up this study to further determine the effect of cannabis on driving.

METHODS

We used a cross-sectional, case-control design with drivers aged 20-49 who were involved in a fatal crash in the United States from 1993 to 2003; drivers were included if they had been tested for the presence of cannabis and had a confirmed blood alcohol concentration of zero. Cases were drivers who had at least one potentially unsafe driving action recorded in relation to the crash (e.g., speeding); controls were drivers who had no such driving action recorded. We calculated the crude and adjusted odds ratios (ORs) of any potentially unsafe driving action in drivers who tested positive for cannabis but negative for alcohol consumption. In computing for the adjusted OR, we controlled for age, sex, and prior driving record.

RESULTS

Five percent of drivers tested positive for cannabis. The crude OR of a potentially unsafe action was 1.39 (99% CI = 1.21-1.59) for drivers who tested positive for cannabis. Even after controlling for age, sex, and prior driving record, the presence of cannabis remained associated with a higher risk of a potentially unsafe driving action (1.29, 99% CI = 1.11-1.50).

CONCLUSION

Cannabis had a negative effect on driving, as would be predicted from human performance studies. This finding supports the need for interventions to decrease the prevalence of driving under the influence of cannabis, and indicates that further studies should be conducted to investigate the dose-response relationship between cannabis and safe driving.

Traffic safety in the U.S.: re-examining major opportunities

INTRODUCTION

This article examines five major road-safety risk factors: exceeding posted speed limits, not using safety belts, driving while intoxicated, nighttime driving, and young drivers.

METHOD

The importance of each of these factors is documented, known effective countermeasures (both policy and technology based) are discussed, and impediments to the implementation of these countermeasures in the United States are examined.

RESULTS

Based on current understanding of the five major risk factors, and of the available countermeasures, there appear to be a variety of opportunities to make substantial gains in road safety using existing knowledge. The limited implementation of a variety of known countermeasures therefore appears to be inconsistent with high-level, strategic goals to improve road safety. Consequently, a recommendation is made to comprehensively re-examine the balance between the countermeasures discussed in this article and economic, mobility, and privacy concerns. IMPACT ON PUBLIC SAFETY: Such a re-examination is likely to result in broad support for these countermeasures, with a consequent major improvement in road safety.

A challenge to the assumed generalizability of prediction and countermeasure for risky driving: different factors predict different risky driving behaviors

In road safety, it may be debated whether all risky behaviors are sufficiently similar to be explained by similar factors. The often assumed generalizability of the factors that influence risky driving behaviors has been inadequately tested. Study 1 (N=116) examined the role of demographic, personality and attitudinal factors in the prediction of a range of risky driving behaviors, for young drivers. Results illustrated that different driving behaviors were predicted by different factors (e.g., speeding was predicted by authority--rebellion, while drink driving was predicted by sensation seeking and optimism bias). Study 2 (N=127) examined the generalizability of these results to the general driving population. Study 1 results did not generalize. Predictive factors remained behavior-specific, but different predictor-behavior relationships were observed in the community sample. Overall, results suggest that future research and practice should focus on a multi-factor framework for specific risky driving behaviors, rather than assuming generalizability across behaviors and driving populations.

Drugs and driving: when science and policy don't mix

This commentary briefly looks at the Canadian federal government's proposed legislation to strengthen the enforcement of drug-impaired driving, placing special emphasis on cannabis. After outlining the legislation, three issues are examined. Of primary concern is at what level cannabis use impairs driving ability leading to an increased risk of motor vehicle collision. Current epidemiological evidence is reviewed. Equally important is the government's emphasis on the training and implementation of Drug Recognition Experts (DREs), specially trained police officers whose role is to detect drivers under the influence of drugs. Research on the effectiveness of DREs is discussed, along with a dialogue regarding the potential shortcomings of the DRE program. Finally, a brief surveillance of international policy literature on drugs and driving is offered, along with some sober thoughts on the potential difficulties that may emerge in the enforcement of the proposed legislation.

Motor vehicle collision risk and driving under the influence of cannabis: evidence from adolescents in Atlantic Canada

OBJECTIVE

Employing a sample of 6087 senior students in Atlantic Canada, this paper examines the relationship between driving under the influence of cannabis (DUIC) and motor vehicle collision (MVC) risk. A series of models were analyzed adjusting for demographic characteristics, driver experience, and substance use.

METHODS

Participants were drawn from the 2002/2003 Student Drug Use Survey in the Atlantic Provinces, an anonymous cross-sectional survey of adolescent students in the Atlantic provinces of Canada. Logistic regression techniques were employed in the analysis of unadjusted and adjusted models.

RESULTS

Among senior students, the prevalence of DUIC in the past year was 15.1% while the prevalence of MVCs was 8.1%. The predictors of DUIC were gender, driver experience, use of a fake ID, and driving under the influence of alcohol (DUIA). The predictors of MVC were gender, driver experience, DUIC, and DUIA.

CONCLUSIONS

These findings extend our knowledge of DUIC as a socio-legal and public health issue with implications on road safety. Effort must be placed on educating new drivers about cannabis use in the context of driving.