Marijuana trajectories and associations with driving risk behaviors in Canadian youth

Objective: Research on risky driving practices involving marijuana use among youth and young adults often relies on cross-sectional data, which fail to account for longitudinal changes in substance use patterns. A better understanding of the longitudinal patterns of marijuana use and its effect on risky driving practices during young adulthood is needed in order to better inform prevention efforts. The current study examined whether different longitudinal patterns of marijuana use across the transition from adolescence to young adulthood are associated with impaired driving risks in young adulthood.

Methods: Data were from the longitudinal Victoria Healthy Youth Survey, which interviewed youth biennially on 6 occasions across 10 years (2003 to 2013).

Results: Youth who reported consistently high levels of marijuana use from adolescence to young adulthood (chronic users) and youth who reported increasing levels of use across this period (increasers) were more likely to engage in risky impaired driving behaviors compared to the other 3 user groups (occasional users, decreasers, and abstainers). Frequency of marijuana use was also predictive of impaired driving risks in young adulthood after controlling for individual characteristics (age, sex, socioeconomic status, age of onset of marijuana use), frequency of other substance use (heavy episodic drinking and illicit drug use), and simultaneous use of marijuana and other substances (alcohol and illicit drugs). By young adulthood, youth who use marijuana more than once a week are more likely to simultaneously use alcohol and engage in heavy episodic drinking. They are also more likely take driving risks.

Conclusions: Harm reduction strategies and legislative approaches targeting impaired driving risks associated with marijuana use should include approaches to target these high-risk groups and to reduce simultaneous use of alcohol.     

Examining motor vehicle crash involvement and readiness to change on drinking and driving behaviors among injured emergency department patients

Objective: To measure the effect of motor vehicle crash (MVC) involvement and readiness to change drinking and driving behaviors on subsequent driving and drinking behaviors among injured emergency department (ED) patients who use alcohol at harmful levels.

Methods: This was a secondary analysis of a randomized controlled trial of injured ED patients who screened positive for harmful alcohol use, who at recruitment reported driving in the past 12 months and received at least one of the intended intervention sessions (brief behavioral intervention versus attention placebo control; N = 407). Outcome variables were as follows: (1) change in 6 impaired driving behaviors and (2) report of MVCs and traffic violations in the 12 months following recruitment; predictor variables were as follows: (1) treatment assignment, (2) MVC involvement at recruitment, and (3) baseline readiness to change alcohol use and drinking and driving.

Results: Modeling of change in the 6 impaired driving variables indicated that neither the recruitment visits being MVC related nor baseline readiness to change alcohol use and drinking and driving behaviors predicted greater changes in impaired driving over time. Baseline reports of past moving traffic violations and the ED visit being MVC related predicted a greater likelihood of each behavior at 12 months following study recruitment.

Conclusions: This study and others have demonstrated that ED patients with harmful alcohol use are willing to engage in behavioral interventions directed at changing risky behaviors. However, this study did not demonstrate that patients considered having the potential to be more engaged with the intervention because their ED visit was MVC related and/or they had expressed intent to change their risky alcohol use and drinking and driving behaviors were more likely to change these risky behaviors.     

The role of personality characteristics in young adult driving

BACKGROUND: Motor vehicle injury is the major cause of mortality among young adults. Information about the individual characteristics of those who drive dangerously could enhance traffic safety programs. The goal of this research was to examine the association between various personality-related characteristics and risky driving behaviors. METHODS: Young adults in Michigan, USA (n = 5,362) were surveyed by telephone regarding several personality factors (risk-taking, hostility, aggression, tolerance of deviance, achievement expectations) and driving behaviors (competitive driving, risk-taking driving, high-risk driving, aggressive driving, and drink/driving). Michigan driver records were obtained to examine offenses, serious offenses, driving offense points, crashes and serious crashes in the three pre-interview years. Multivariate regression analyses, adjusting for age, race, and marital status were conducted separately by sex to identify personality factors related to driving. RESULTS: For men and women, greater risk-taking propensity, physical/verbal hostility, aggression, and tolerance of deviance were significant predictors of a competitive attitude toward driving, risk-taking driving, high-risk driving, driving aggression, and drink/driving. Greater risk-taking propensity, physical/verbal hostility, aggression, and to a small degree, expectations for achievement predicted higher numbers of offenses, serious offenses, and points. CONCLUSION: Traffic safety policies and programs could be enhanced through recognition of the role personality factors play in driving behavior and the incorporation of this knowledge into the design and implementation of interventions that modify the behaviors associated with them.     

The effects of minimum legal drinking age 21 laws on alcohol-related driving in the United States

Objective

To examine trends in alcohol consumption and alcohol-related crashes among people younger than 21 in the United States and to review evidence on the effects of minimum legal drinking age (MLDA) laws.

Methods

Trends in alcohol-related crashes and alcohol consumption among young people were examined, and studies on the effects of lowering and raising the drinking age were reviewed.

Results

MLDA laws underwent many changes during the 20th century in the United States. Since July 1988, the MLDA has been 21 in all 50 states and the District of Columbia. Surveys tracking alcohol consumption among high school students and young adults found that drinking declined since the late 1970 s, and most of the decline occurred by the early 1990 s. These were the years when states were establishing, or reinstating, a MLDA-21. Among fatally injured drivers ages 16-20, the percentage with positive BACs declined from 61% in 1982 to 31% in 1995, a bigger decline than for older age groups; declines occurred among the ages directly affected by raising MLDAs (ages 18-20) and among young teenagers not directly affected (ages 16-17). Almost all studies designed specifically to gauge the effects of drinking age changes show MLDAs of 21 reduce drinking, problematic drinking, drinking and driving, and alcohol-related crashes among young people. Yet many underage people still drink, many drink and drive, and alcohol remains an important risk factor in serious crashes of young drivers, especially as they progress through the teenage years. Stepped-up enforcement of MLDA and drinking and driving laws can reduce underage drinking. Recent efforts to lower MLDAs to 18 and issue licenses to drink upon completion of alcohol education have gained local and national media attention. There is no evidence that alcohol education can even partially replace the effect of MLDA-21.

Conclusions

The cause and effect relationship between MLDAs of 21 and reductions in highway crashes is clear. Initiatives to lower the drinking age to 18 ignore the demonstrated public health benefits of MLDAs of 21.

Impact on Industry

Lowering the drinking age to 18 will increase highway crash deaths among young people.     

Changes in risky driving behavior from age 21 to 26 years

Aim: The aim of this study was to determine whether the prevalence of risky driving behavior changed between ages 21 and 26 years, among a cohort of young people. Method: This study was part of the Dunedin Multidisciplinary Health and Development Study, which is a longitudinal study of a birth cohort. This study involved examining changes in the prevalence of risky driving behavior among young adults at ages 21 and 26 years. At both ages, 936 members of the cohort were administered face-to-face interviews, using a structured questionnaire that included items on a range of risky driving and thrill-seeking activities. Results: The results showed that risky driving was predominantly a male activity, but by 26 years of age, many had “matured out” of this behavior. At the same time, the desire for thrill-seeking increased among the males. Among the females, there were few significant changes between ages 21 and 26 years, but at both ages, the prevalence of risky driving and thrill-seeking was relatively low. Impact on industry: These results show that the main target population for road safety interventions aimed at reducing risky driving behavior should be young, male drivers.     

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.     

Underage drinking: frequency, consequences, and interventions

OBJECTIVES: To examine the frequency of underage drinking, driving after drinking and alcohol-related crashes, trends in these behaviors, and promising interventions. METHODS: We examined drinking and drinking- and-driving behaviors reported in the United States in the 2001 U.S. National Household Survey of Drug Abuse, the Centers for Disease Control and Prevention 2001 Youth Risk Behavior Survey, the 1992 National Longitudinal Alcohol Epidemiologic Study, and the 1999 National Survey of Drinking and Driving conducted for the National Highway Traffic Administration. We also examined the 1999 European School Survey Project on Alcohol and Other Drugs. Alcohol-related fatal crashes were examined from the U.S. Fatality Analysis Reporting System. Evaluation of interventions to reduce teenage drinking and driving after drinking were reviewed. RESULTS: In the United States, 19% of youth ages 12-20 consumed five or more drinks on an occasion in the past 30 days. Although European nations have lower legal drinking ages (16-18) than in the United States (21), similar proportions engage in underage drinking. In two-thirds of European countries, a greater percentage of 15-16 year-olds drank five or more drinks on an occasion in the past month than in the United States. In both the United States and Europe, the earlier people begin to drink, the greater the likelihood of developing alcohol dependence and other alcohol-related problems, including alcohol-related crash involvement, during adolescence and adult years. During the past 20 years alcohol-related traffic deaths among people younger than 21 have been cut in half in the United States, but progress has halted since 1995 and the problem is still large. Interventions shown by research to reduce alcohol-related crashes among youth include raising the legal drinking age to 21, zero tolerance laws, and some interventions that are family, school, or community based. CONCLUSIONS: Despite research showing that a variety of interventions can reduce underage drinking and alcohol-related crash fatalities, the frequency of these behaviors remains high and the average age of drinking initiation is declining in the United States. Efforts are needed to enhance publicized enforcement of underage drinking laws. Comprehensive community interventions that include enforcement of these laws also are needed.     

Seat-Belt Use and Related Behaviors Among Young Adults

Seat-belt use among young adults was examined to identify factors associated with nonuse. This research was part of the Dunedin Multidisciplinary Health and Development Study, which is a study of the health, development, and behavior of a birth cohort of young New Zealanders (n = 1037). At age 21 years, 948 (93%) members of this cohort were administered a face-to-face interview where they were asked about seat-belt use (self and friends), reasons for nonuse, and also their involvement in risky driving practices, motor-vehicle traffic crashes, and some thrill-seeking activities. Results showed relatively high front seat-belt use (85–96%) but low rear use (29–47%). Some differences in use were a function of gender and seating location. Generally, users had higher academic qualifications and lower risky driving behavior (males only), but did not differ significantly as far as crash experiences and thrill-seeking activity was concerned. The main reasons for not using a seat belt were forgetfulness/laziness, a perceived low risk of injury, and discomfort. This study provided information about the background and behavior of young adults who do not use seat belts, which could be helpful when designing strategies to promote seat-belt use in this age group.     

Adolescent, and their parents, attitudes towards graduated driver licensing and subsequent risky driving and crashes in young adulthood

Problem

Although Graduated Driver Licensing Systems (GDLS) have helped reduce young driver crash rates, they remain significantly over-represented in crash statistics. To be effective GDLS rely heavily on support for the legislation by those directly involved; parents to enforce the restrictions and adolescents to comply. There is some evidence that practices regarding GDLS restrictions influence adolescent driving outcomes in the early stage of licensure. However there has been no examination undertaken on the influence of parent and adolescent attitudes toward GDLS on adolescents’ driving behavior and crash experiences as they move into their young adult years. The aim of this research was to examine these relationships.

Method

This investigation was based on a longitudinal study of a birth cohort, and uses data collected when the cohort members were aged 15, 18, and 21 years. At age 15 both adolescent and their parent attitudes toward GDLS were measured. At age 18 adolescent GDLS attitudes were measured again. The association between these measures and self-reported risky driving behavior and crash involvement at age 21 were examined.

Results

Negative attitudes toward the learner supervisor restriction for males, and negative attitudes toward a GDLS for females were strongly associated with risky driving and crash involvement as young adults.

Impact on industry

Targeting interventions to improve adolescents and parents understanding of the reasons for graduated licensing and the specific restrictions may improve attitudes and views and thereby contribute to a reduction in risky driving behaviors and crash risk among young adults.     

Hardcore drinking drivers and other contributors to the alcohol-impaired driving problem: need for a comprehensive approach

OBJECTIVE: Understanding the hardcore drinking driver concept in the context of the alcohol-impaired driving problem. METHOD: Review of the relevant literature. RESULTS: As progress against alcohol-impaired driving slowed in the early 1990s, public and political attention turned to "hardcore" drinking drivers, and they have been a priority for the past 15 years. Though intuitive, the hardcore concept has been difficult to conceptualize. Its definition of hard-to-change chronic heavy drinking drivers focuses on a group that is not easily identifiable and ignores many who account for a large portion of alcohol-impaired driving crashes. These include drivers who drink heavily on occasion and drivers who drink at more moderate levels that elevate crash risk. Emphasis on the hardcore has focused attention on the small proportion of drinking drivers who have been detected and arrested, whereas the vast majority of drinking drivers go undetected. Some countermeasures aimed at the hardcore group have been effective in reducing recidivism, but attention and resources also need to be given to general deterrent initiatives (e.g., 0.08 g/dL, sobriety checkpoints, administrative license suspension). There has been no reduction in the overall alcohol-impaired driving problem since the mid-1990s. CONCLUSION: Reductions in the alcohol-impaired driving problem require that attention be focused on all relevant target groups. Some benefits could accrue by recognizing that countermeasures developed for hardcore drinking drivers, such as alcohol ignition interlocks and vehicle or plate impoundment, might also be effective with more numerous first-time offenders. However, such strategies are likely to be most effective against recidivism (specific deterrence). Greater gains could be achieved through general deterrent efforts (increasing the real and perceived risk of arrest and punishment to all drinking drivers), along with application of public health measures designed to reduce overall consumption. Additional ways need to be found to separate drinking and driving, either through cultural changes in drinking and/or driving behavior or, in the future, with the use of technology that can make vehicles inoperable by drivers with illegal blood alcohol concentrations.     

The relationship between blood alcohol concentration (BAC), age, and crash risk

PROBLEM: The role of age (youth and driving inexperience) and alcohol as major risk factors in traffic crash causation has been firmly established by numerous studies over the past 50 years. Less well established is how the two variables interrelate to influence crash risk. Some investigations have hypothesized an interactive or synergistic effect in which young drivers with less experience and a greater tendency to take risks are more adversely affected at lower blood alcohol concentrations (BACs) than are older drivers. The evidence for this hypothesis is mixed. Resolution of this issue has important implication for developing countermeasures directed at the young driver crash problem. METHOD: Case control data previously collected in Long Beach and Fort Lauderdale were reanalyzed using a more sensitive method for detecting interaction effects than used in the original analysis. A conditional logistic regression analyses found a highly significant agexBAC interaction (P<.0001) involving differences between drivers under 21 and those 21 and older. DISCUSSION: The results clearly indicate that positive BACs in drivers under 21 are associated with higher relative crash risks than would be predicted from the additive effect of BAC and age. It is likely that two mechanisms are operating to cause the interaction. First, it seems likely that the crash avoidance skill of young novice drivers would be more adversely affected by alcohol due to their driving inexperience, immaturity, and less experience with alcohol. Second, drivers under 21 who choose to drink and to drive after drinking probably have pre-existing characteristics that predisposed them to risk taking and crash involvement apart from any increased vulnerability to alcohol impairment. IMPACT ON INDUSTRY: The results support increased enforcement of zero-tolerance BAC laws for minors.     

Young people driving after drinking and riding with drinking drivers: drinking locations--what do they tell us?

OBJECTIVE: The present study investigated the extent to which drinking in specific locations and heavy drinking mediated the effects of overall alcohol use on driving after drinking (DD) and riding with drinking drivers (RWDD) among young people. Additionally, this study examined the relationships among ethnicity, gender, drinking in specific locations, and DD and RWDD. METHOD: Using random-digit dialing procedures, participants were recruited to take part in a telephone survey in California, United States of America. Participants were 1,534 youth, ages 15-20 years (mean age = 17.6). Latinos, African Americans, and Asian Americans were over-sampled to allow cross-group comparisons. Along with background characteristics, overall alcohol use, heavy drinking, drinking in specific locations, DD, and RWDD were measured. RESULTS: Latent variable structural equation modeling showed that European Americans, males, older adolescents, those who have a driver license, and those who drive more often were more likely to report drinking alcohol in the past year. Heavy episodic drinking and drinking in cars increased both DD and RWDD. Drinking in restaurants also increased DD. The effects of overall alcohol consumption on DD were entirely mediated through heavy episodic drinking and drinking in restaurants and cars. Alcohol consumption had both direct and indirect effects on RWDD. With the exception of being Latino and frequency of driving, the effects of the background variables on RWDD were all entirely mediated through alcohol consumption. CONCLUSIONS: Heavy drinking and drinking in specific locations appeared to be important unique predictors of both DD and RWDD. In light of the relationship between drinking in restaurants and in cars, and DD, prevention programs and policies aimed at underage drinking should focus on developing more effective responsible beverage service programs, increasing compliance with laws limiting alcohol sales to youth, and enforcing graduated driver licensing and zero tolerance laws.     

Young driver risk in relation to parents' retrospective driving record

PROBLEM: Parents are an important potential influence on the driving safety of their children. This study examined the relationship of parental driving record on male and female offspring's at-fault collision risk. METHOD: Drivers aged 16-21 on the date of full licensure were selected from driver records and a matching process was used to identify putative parents in two-parent households. Poisson regression models were developed to predict at-fault collisions of male and female youth in the three years following full licensure from parents' at-fault collisions, speeding offenses, and other moving offenses in the four years prior to children's licensure. One set of models examined the relative risk associated with increasing numbers of maternal and paternal at-fault collisions and offenses. Other models examined the joint versus separate maternal and parental contributions. RESULTS: Controlling for region of residence, both mothers' and fathers' at-fault collisions were associated with an increased risk in both male and female youth at-fault collisions. Mothers' and fathers' speeding offenses were also associated with increased relative risk of at-fault collisions for both sons and daughters, while fathers' other moving offenses increased collision risk for sons but not daughters. DISCUSSION: Further research is required to identify how parental driving risk is transmitted to children. IMPACT ON INDUSTRY: (a) Parents of young children should be informed of their role in influencing their children's future driving risk; (b) The results identify risk factors that could be of interest to licensing authorities and the insurance industry.     

Drinking to cope and self-medication: Characteristics of jobs in relation to workers' drinking behavior

This research extends recent studies of the relationship between characteristics of jobs and patterns of workers' alcohol consumption. Working within a ‘generalization perspective ’whereby job conditions are seen as having important effects on the mental health and behaviors of workers in non-work settings, the current research derives and tests a model of four job-related factors as they influence three aspects of alcohol use; the simple frequency—quantity of drinking, escapist-oriented reasons for drinking, and a combination of heavier drinking with escapist-oriented definitions which is labeled ‘self-medication’. Analyses of data drawn from the 1973 Quality of Employment Survey (QES) indicate that the relationship between jobs and drinking behavior is more complex than previously conceptualized. Specifically, we find evidence that for working men characteristics of jobs affect levels of alcohol consumption and the incidence of self-medicating drinking. These findings support and refine job-based explanations of drinking behavior. The implications of these findings for subsequent research and model-specification are discussed.     

The effect of a campus-community environmental alcohol prevention initiative on student drinking and driving: results from the "a matter of degree" program evaluation

OBJECTIVE: Motor vehicle crashes involving alcohol are a major contributor to morbidity and mortality among college students in the United States. This study evaluates the effect on drinking and driving outcomes of the "A Matter of Degree" program, a campus-community coalition initiative to reduce college binge drinking. METHODS: We used a quasi-experimental longitudinal study design that compared student responses at 10 colleges participating in the program and students attending 32 similar colleges that did not participate in the program. We also divided the program sites into two groups of five according to their level of program implementation and compared each with the non-program colleges. We examined driving after any alcohol consumption and driving after five or more drinks among drinkers who drove one or more times a week per month and riding with a high or drunk driver among all students at these colleges beginning in 1997 through 2001. Outcomes were based on data collected from repeated cross-sectional surveys using the Harvard School of Public Health College Alcohol Study. Analyses were conducted using MLwiN multilevel statistical software. RESULTS: We found significant reductions in driving after drinking, driving after five or more drinks and riding with a high or drunk driver at the program colleges relative to the comparison colleges. Further analyses indicated that these reductions among the AMOD program colleges occurred at the sites with high program implementation relative to comparison sites, while no statistically significant change was noted at the program sites with low implementation. The program effect on the two drinking and driving outcomes appeared to be mediated by frequent binge drinking, while significant decline in the riding with an intoxicated driver outcome was not mediated by the individual's drinking. CONCLUSIONS: Campus-community based environmental alcohol prevention is a promising approach for reducing alcohol-impaired motor vehicle crashes among this population.     

Smoking is a marker of risky behaviors independent of substance abuse in injured drivers

OBJECTIVE: Smoking has been linked to disease and injury. The purpose of this study is to investigate the smoking habits of motor vehicular driver trauma center patients and their association with previous injury history and risky behaviors. METHODS: The studied population included 323 motor vehicular driver injury patients (123 smokers and 200 non-smokers) interviewed as part of a larger study of psychoactive substance use disorders at an adult Level I trauma center. Patients with head injuries, hospital stays of less than two days, and diminished cognition were excluded. Interviews included demographics (age, gender, race, marital status), socioeconomic status (SES; income, education, employment), risky behaviors (seatbelt non-use, drinking and driving, riding with drunk driver, binge drinking), and trauma history information (vehicular, assault, and other injuries). Substance abuse (alcohol and drug dependence) was evaluated in depth using DSM III-R criteria. Smokers and non-smokers were compared in relation to control and dependent variables using student's t test and chi-square (alpha = 0.05). Outcome variables included previous trauma history and risky behaviors. Multiple logistic regression models using step-down selection methods (alpha = 0.05) were constructed with risky behaviors and trauma history as dependent variables including demographics, SES and substance as independent variables. RESULTS: Smokers represented 38 percent of the 323 patients studied. Smokers (n = 123) were younger (34 vs. 43 years), more likely to be male (72 percent vs. 50 percent), not married (72 percent vs. 56 percent), and had higher rates of alcohol (29 percent vs. 9 percent) and drug dependence (14 percent vs. 3 percent) than non-smokers (n = 200). Educational achievement (20 percent vs. 15 percent less than high school) and income level (24 percent vs. 23 percent with less than $15,000 of yearly income) were not different between smokers and non-smokers. Smokers were more likely than non-smokers to have a history of prior vehicular trauma (48 percent vs. 26 percent), assault (25 percent vs. 9 percent), or other injury (50 percent vs 37 percent). The following injury-prone behaviors were also more common among the smokers than non-smokers: seatbelt non-use (49 percent vs. 29 percent), drinking and driving (38 percent vs. 15 percent), riding with drunk driver (38 percent vs. 13 percent), and binge drinking (68 percent vs. 26 percent). In multiple logistic regression models adjusting for demographics, SES, and substance abuse, smoking revealed significantly higher odds ratios (OR) for the following dependent variables: seatbelt non-use (OR = 2.9), riding with drunk driver (OR = 2.2), binge drinking (OR = 2.4), previous vehicular (OR = 2.0), and assault injuries (OR = 2.5). Smoking did not reach significance for drinking and driving and other (non-vehicular and non-assault) injury. CONCLUSION: Smoking is independently associated with risky behaviors and repeated history of vehicular or assault injury within the vehicular trauma population.     

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.     

The impact of changes to the NSW graduated driver licensing system on subsequent crash and offense experience

Introduction: In mid-2007 the State of New South Wales (NSW) in Australia introduced modifications to the existing graduated driver licensing system, lengthening the mandatory number of supervised hours for learner drivers aged under 25 years from 50 to 120 and extending the minimum learner period from 6 to 12 months. Additional driving restrictions were also introduced for young drivers in the two provisional licensed periods, P1, P2. This paper aims to evaluate this change by comparing the crash and offense experiences of young learner drivers before and after it occurred. Method: From driver licensing files supplied by the NSW transport authority two cohorts of persons obtaining their initial learner's permits in the year prior to the changes and in the subsequent year were constructed with demographic data, dates of transition to the driving phases, dates of crashes, and dates and types of traffic offenses. Both cohorts comprised around 100,000 individuals. Crash rates per 100 years of person-time under observation post P1 with their standard errors were calculated. Using a survival-analytic approach the proportion of crashes of all types were graphed in three month periods post P1. Sexes were treated separately as were initial learner ages of 16, 17, 18–21, and 22–24 years. The distribution of traffic offense types during P1 and P2 phases were also compared. With such large numbers formal statistical testing was avoided. Results: No meaningful differences in the crash or offense experiences of the two cohorts in either sex or at any age were observed. Delaying progress to unsupervised driving has road safety benefits. Conclusions: At least in conditions similar to those in NSW, requiring more than 50 h of supervised driving seems to have few road safety benefits. Practical applications: Licensing authorities should be cautious in extending the mandated number of supervised driving hours beyond 50.     

Persistence of Violation and Crash Behavior Over Time

This analysis examines the ability of previous offenses to predict future high-risk offenses, and similarly, the ability of crashes to predict future high-risk crashes, using the complete driver history data (up to 9 years) for a set of young Michigan subjects. As expected, those with previous ticketed offenses or reported crashes are at greater risk for future offenses or crashes; with a previous-year serious offense doubling the odds of serious offenses during the subsequent year, and a previous-year at-fault crash increasing the odds of subsequent-year at-fault crashes by nearly 50%. There is modest evidence that serious offenses and at-fault crashes may better predict subsequent behavior in females and in more experienced drivers. This latter finding is also evidenced by the fact that records of these young drivers are less predictive of subsequent driving history than is true for records of all drivers in general found in other studies. This suggests that, in the early stages of driving, offenses and crashes are, at least in part, attributable to inexperience, and hence, characteristic of all beginning drivers.     

Implicit attitudes towards risky driving behaviors: Evidence of validity for the implicit association test

Introduction: Attitudes toward risky driving behaviors are commonly evaluated through direct self-report measures. Nevertheless, these instruments have limitations, such as socially-desirable responding. This study examines the validity of the Implicit Association Test (IAT) as an indirect measure of attitudes towards risky driving. An IAT with “risky” vs. “safe” driving behaviors categories was evaluated. Method: A sample of 100 participants (ranging from 18 to 70 years of age) completed the IAT and measures of attitudes, driving styles, personality traits, risk-taking (IOWA Gambling Task), and social desirability (Driver Social Desirability Scale). Results: A high level of internal consistency was found for IAT scores. The IAT was correlated with driving styles (risky, dissociative, and careful dimensions), risk-related personality traits (impulsive/sensation seeking and aggression/hostility) and risk-taking measures. IAT scores were also associated with self-reported risky driving behaviors (r = 0.33). As expected, a higher level of negative implicit attitudes was found among young drivers. The driver social desirability scale was correlated with most self-report measures, but not with the IAT. Conclusion: The present study provides reliability and validity evidence for the IAT as an indirect measure of attitudes towards risky driving. The IAT can serve as an important complement to conventional self-report measures of driving attitudes. Practical Applications: Potential use of global measure of implicit attitudes toward risky driving behaviors in the evaluation, education, and training of drivers are discussed.