Parental influence on adolescent compliance with graduated driver licensing conditions and crashes as a restricted licensed driver: New Zealand Drivers Study

Aim

To examine the influence of parental knowledge of, and support for graduated driver licensing (GDL) conditions, parental management of adolescent driving and parental driving behaviour on adolescent compliance with GDL conditions and crashes as a restricted licence driver.

Method

This research was part of the New Zealand Drivers Study (NZDS), a prospective cohort study of 3992 newly licensed car drivers. NZDS participants were recruited at the learner licence stage, with follow-up aligned with the GDL stages. At the restricted licence stage 1200 parents of NZDS adolescents, aged 15–17 years at learner licensure, were recruited and completed interviews. 895 of these adolescents progressed to their full licence and completed the full licence interview. These 895 parent–adolescent pairs were the study population in this research. Topics examined included parental knowledge of, and support for GDL conditions, management of adolescent driving (driving rules, adolescent vehicle ownership, delaying licensure), and their own driving behaviours. Outcomes examined were adolescent compliance with GDL restricted licence conditions (night-time and passenger), and crashes as a driver during the restricted licence stage.

Results

After controlling for other variables, factors independently associated with adolescent low compliance with GDL conditions were: low parental knowledge of conditions, parents’ implementing few driving rules, adolescent vehicle ownership, and parent crash involvement. Factors independently associated with adolescents being a crash involved driver were: parents’ actively delaying licensure, adolescent vehicle ownership, and parent crash involvement.

Conclusion

There is increasing recognition of the importance of parental involvement in adolescent driving. The results show that parents are influential in determining adolescent compliance with GDL and risk of crash. Parents can have considerable positive influence on their adolescent's driving through ensuring compliance with the components of GDL, limiting vehicle ownership and by modelling safe driving behaviours.     

The effect of the learner license Graduated Driver Licensing components on teen drivers’ crashes

Background

Most studies evaluating the effectiveness of Graduated Driver Licensing (GDL) have focused on the overall system. Studies examining individual components have rarely accounted for the confounding of multiple, simultaneously implemented components. The purpose of this paper is to quantify the effects of a required learner license duration and required hours of supervised driving on teen driver fatal crashes.

Methods

States that introduced a single GDL component independent of any other during the period 1990–2009 were identified. Monthly and quarterly fatal crash rates per 100,000 population of 16- and 17-year-old drivers were analyzed using single-state time series analysis, adjusting for adult crash rates and gasoline prices. Using the parameter estimates from each state's time series model, the pooled effect of each GDL component on 16- and 17-year-old drivers’ fatal crashes was estimated using a random effects meta-analytic model to combine findings across states.

Results

In three states, a six-month minimum learner license duration was associated with a significant decline in combined 16- and 17-year-old drivers’ fatal crash rates. The pooled effect of the minimum learner license duration across all states in the sample was associated with a significant change in combined 16- and 17-year-old driver fatal crash rates of −.07 (95% Confidence Interval [CI] −.11, −.03). Following the introduction of 30 h of required supervised driving in one state, novice drivers’ fatal crash rates increased 35%. The pooled effect across all states in the study sample of having a supervised driving hour requirement was not significantly different from zero (.04, 95% CI −.15, .22).

Conclusion

These findings suggest that a learner license duration of at least six-months may be necessary to achieve a significant decline in teen drivers’ fatal crash rates. Evidence of the effect of required hours of supervised driving on teen drivers’ fatal crash rates was mixed.     

Trajectories of kinematic risky driving among novice teenagers

Objectives

Elevated gravitational force event rates are associated with the likelihood of a crash or near crash and provide an objective measure of risky driving. The purpose of this research is to examine the patterns over time of kinematic measures of risky driving among novice teenage drivers.

Methods

Driving data were collected from 42 newly licensed teenage drivers during the first 18 months of licensure. Data recording systems installed in participants’ vehicles provided information on driving performance and driver characteristics. Latent class and logistic regression models were used to analyze trajectories of elevated gravitational-force (g-force) event rates, called kinematic risky driving, with respect to risk groups and associated factors.

Results

Kinematic risky driving over the 18-month study period was best characterized as two classes, a higher-risk and a lower-risk class. The rate of kinematic risky driving during the first 6 months generally maintained over 18 months. Indeed, of those classified by latent class analysis as higher risk, 88.9%, 94.4% and 94.4% had average event rates above the median in the 1st, 2nd, and 3rd 6-month periods, respectively, indicating substantial tracking over time. Friends’ risky driving, friends’ risky behavior, self-reported risky driving, and perceptions about risky driving and driving privileges were associated with trip-level rates of kinematic risky driving. However, none of these factors was associated with trip-level rates after stratifying by overall risk in a latent class model, although friend's risky driving was marginally significant.

Conclusion

Kinematic risky driving tended to track over time within the lower and higher risky driving groups. Self-reported risky driving and having risky friends were predictors of kinematic risky driving rates, but these variables did not explain the heterogeneity within higher and lower classes of risky drivers.     

Pre-licensed driving experience and car crash involvement during the learner and restricted,licence stages of graduated driver licensing: Findings from the New Zealand Drivers Study

Objective

The aim of this study was to determine whether pre-licence driving experiences, that is driving before beginning the licensing process, increased or decreased crash risk as a car driver, during the learner or the restricted licence stages of the graduated driver licensing system (GDLS).

Method

Study participants were 15–24 year old members of the New Zealand Drivers Study (NZDS) – a prospective cohort study of newly licensed car drivers. The interview stages of the NZDS are linked to, the three licensing stages of the GDLS: learner, restricted and full. Baseline demographic (age, ethnicity, residential location, deprivation), personality (impulsivity, sensation seeking, aggression) and, behavioural data, (including pre-licensed driving behaviour), were obtained at the learner licence interview. Data on distance driven and crashes that occurred at the learner licence and restricted licence stages, were reported at the restricted and full licence interviews, respectively. Crash data were also obtained from police traffic crash report files and this was combined with the self-reported crash data. The analysis of the learner licence stage crashes, when only supervised driving is allowed, was based on the participants who had passed the restricted licence test and undertaken the NZDS, restricted licence interview (n = 2358). The analysis of the restricted licence stage crashes, when unsupervised driving is first allowed, was based on those who had passed the full licence test and completed the full licence interview (n = 1428).

Results

After controlling for a range of demographic, personality, behavioural variables and distance driven, Poisson regression showed that the only pre-licence driving behaviour that showed a consistent relationship with subsequent crashes was on-road car driving which was associated with an increased risk of being the driver in a car crash during the learner licence period.

Conclusion

This research showed that pre-licensed driving did not reduce crash risk among learner or restricted licensed drivers, and in some cases (such as on-road car driving) may have increased risk. Young people should be discouraged from the illegal behaviour of driving a car on-road before licensing.     

The characteristics of young pre-licensed drivers: Evidence from the New Zealand Drivers Study

Aim

The aim of this study was to identify demographic and behavioural factors associated with pre-licensed driving.

Method

A cohort comprising 3526 newly licensed drivers aged 15–24 years old from throughout New Zealand completed a questionnaire which sought information on pre-licensed driving behaviour and factors thought to be related to this.

Results

Almost half of the participants had driven on-road prior to passing their learner license theory test; 14% had driven more than 20 times; and 7.5% had driven more than 200 km. Multivariate logistic regression showed the results differed depending on the outcome examined. In general pre-licensed driving was significantly higher among males, among Māori, those living in a rural area, and those living in an area of high deprivation. Furthermore, those who drove pre-licensed were more likely to engage in other risky behaviours such as hazardous drinking and cannabis use, and have medium to high scores for sensation seeking and aggression/hostility.

Conclusion

The young people who were pre-licensed drivers displayed a range of demographic and behavioural characteristics that indicate they may be at higher crash risk than their peers who did not drive before licensing. Identifying those who drive before licensing and targeting road safety interventions towards this group may help reduce the high crash risk among novice drivers.     

Unlicensed driving and other related health risk behaviors: A study of Montana high school students

Purpose

Health risk behaviors tend to cluster in young people, not least among young drivers. Less is known about the health risk profile of young unlicensed drivers. This study investigates health risk behaviors among young unlicensed drivers compared to both their licensed and driving peers, and their non-driving peers.

Methods

High school students participating in the Youth Risk Behavior Surveillance System in Montana (US) and age-eligible to have a driver's license were studied (n = 5985), categorized according to their self-reported car driving and license practice (licensed driving, unlicensed driving, and non-driving). Ten health risk behaviors, of which four were related to car riding/driving, were considered. Multinomial logistic regression was used to compile sex-specific odds ratios (with 95% confidence intervals) of adopting those behaviors using licensed drivers as a reference and adjusting for age and race/ethnicity.

Results

Health risk behaviors tended to be more common among unlicensed drivers than other groups, although some behaviors were prevalent in all groups (i.e., alcohol use and lack of seat belt use). As a consequence, for both male and female students, there was a significant association between unlicensed driving and most health risk behaviors, except for being involved in a physical fight and riding with a drinking driver among female students.

Conclusions

Young unlicensed drivers are more likely than licensed drivers to adopt several health risk behaviors both in car driving/riding or otherwise, in particular alcohol use and cigarette smoking. This challenges any simplistic approach as unlicensed driving in youth is not an isolated act suggesting public health and traffic safety initiatives.     

Trends in older driver crash involvement rates and survivability in the United States: An update

Objective

Previous research has shown that fatal crash involvement rates per licensed driver aged 70 and older declined significantly more per year in the United States than rates for middle-aged drivers aged 35–54 during 1997–2008, and per vehicle mile traveled from 1995–1996 to 2001–2002. Analyses of police-reported crash data during 1997–2005 indicated that the greater declines for older drivers were due to decreases in crash involvement and in the risk of dying in the crashes that occurred. The current study examined if trends in crash rates, crash involvements, and survivability persisted into more recent years.

Methods

Trends for drivers 70 and older were compared with trends for drivers aged 35–54 for U.S. national fatal passenger vehicle crash involvements per 100,000 licensed drivers during 1997–2012 and for U.S. national fatal passenger vehicle crash involvements per vehicle miles traveled in 1995–1996, 2001–2002, and 2008. Using police-reported crash data during 1997–2008 from 20 U.S. states, trends in involvement rates in non-fatal crashes of various severities per 100,000 licensed drivers and changes in the odds of death and the odds of death or serious injury in a crash were compared between older and middle-aged drivers.

Results

During 2007–2012, declines in national fatal crash involvement rates per licensed driver were similar for drivers 70 and older and middle-aged drivers (18 percent each). However, when considering the entire study period, fatal crash involvement rates continued to reflect a substantially larger decline for drivers 70 and older than for middle-aged drivers (42 vs. 30 percent per licensed driver during 1997–2012, 39 vs. 26 percent per vehicle mile traveled from 1995–2006 to 2008). When analyses of police-reported crash data were extended through 2008, non-fatal injury crash involvement rates per licensed driver declined more for older than for middle-aged drivers (39 vs. 30 percent), and unlike in prior research, average annual declines were significantly larger for drivers 80 and older. Property damage-only crash involvement rates similarly declined significantly more for older than for middle-aged drivers (15 vs. 3 percent). Drivers 70 and older in 1997 were 3.5 times more likely than middle-aged drivers to die in a crash, and this ratio declined to 3.2 by 2008.

Conclusions

Although declines in fatal crash involvement rates in recent years have not differed between older and middle-aged drivers, this did not undo earlier gains for older drivers. The recent slowing in the relative magnitude of the decline for older drivers may be related to the differential effect of the U.S. recession on fatal crash involvements of drivers in these age groups. The decreased likelihood of being involved in a crash of any severity and increased survivability when a crash occurred held when examining data through 2008, and for drivers 80 and older, significant declines in crash involvement relative to middle-aged drivers extended to non-fatal injury crashes.     

Non-compliance with graduated driver licensing (GDL) requirements: Changes in GDL-related conviction rates over time among 16–17-year-old California drivers

Introduction

Self-reports by novice teen drivers in California and elsewhere suggest that many violate graduated driver licensing (GDL) nighttime and passenger restrictions, and to a lesser extent, drive on learner permits without being supervised. Is this corroborated by their traffic conviction records?

Method

We examined historical aggregated conviction rates for GDL-related violations before and after GDL, and Poisson regressions of conviction rates over time among 16–17-year-old California novices.

Results

During the year before they received their provisional licenses, <1% of 16-year-old novices and <2% of 17-year-old novices were convicted of driving unlicensed or unsupervised on their learner permits. Statewide historical conviction rates for these offenses were not higher after GDL was implemented, despite the longer holding period. Convictions for violating GDL nighttime or passenger restrictions were highest almost immediately after provisional licensure, though only about 3% of 16-year-old novices and 2% of 17-year-old novices were ever convicted of violating either restriction.

Discussion

California 16–17-year-old novice drivers were very rarely convicted of GDL-related violations. The contradictive, large differences between the current findings and self-report surveys are likely due in part to the fact that most self-reports assessed only whether teens had ever violated a GDL-related requirement, which exaggerates prevalence. Our conviction findings are more similar to estimates of non-compliance with GDL-related requirements from naturalistic driving studies that monitor actual driving behavior and take exposure into account, but are lower likely due to issues related to detection, enforcement, and adjudication of violations, as well as limitations of existing naturalistic studies.     

Graduated driver licensing program component calibrations and their association with fatal crash involvement

Graduated driver licensing (GDL) programs are specialized licensing systems for beginner drivers adopted in all U.S. states, Australia, Canada, and New Zealand. GDL programs reduce novice drivers’ exposure to high-risk driving situations while they gain driving experience. Several studies document the success of GDL programs overall in reducing young teen crash rates. However, little is known about which specific components of these programs (e.g., nighttime driving restrictions) and which calibrations of these components (e.g., 10 PM, 11 PM, 12 AM, or 1 AM), are associated with the largest crash reductions. The goal of this study was to identify the GDL component calibrations associated with the largest reductions in fatal crash involvements for 16–17-year-olds. Driver fatal crash involvements for all U.S. states from 1986 to 2007 were analyzed using Poisson regression models to estimate the association of various GDL component calibrations with 16- and 17-year-old driver fatal crash incidence, after adjusting for potential confounders. We found clear evidence that (a) a minimum learner permit holding period of 9–12 months and (b) a passenger restriction allowing only one teen passenger for 6 months or longer are the calibrations for the learner permit holding period and passenger restriction components associated with the largest reductions in 16–17-year-old driver fatal crash involvements. Additionally, the data suggest that (a) disallowing learner driving until age 16, (b) disallowing intermediate licensure until age 16½ to 17, and (c) a nighttime driving restriction starting at 10 PM or earlier are the calibrations for these components associated with the largest reductions in 16-year-old driver fatal crashes. There was no clear evidence to support particular calibrations for supervised driving hours or unrestricted license ages.     

Naturalistic assessment of novice teenage crash experience

Background

Crash risk is highest during the first months after licensure. Current knowledge about teenagers’ driving exposure and the factors increasing their crash risk is based on self-reported data and crash database analyses. While these research tools are useful, new developments in naturalistic technologies have allowed researchers to examine newly-licensed teenagers’ exposure and crash risk factors in greater detail. The Naturalistic Teenage Driving Study (NTDS) described in this paper is the first study to follow a group of newly-licensed teenagers continuously for 18 months after licensure. The goals of this paper are to compare the crash and near-crash experience of drivers in the NTDS to national trends, to describe the methods and lessons learned in the NTDS, and to provide initial data on driving exposure for these drivers.

Methods

A data acquisition system was installed in the vehicles of 42 newly-licensed teenage drivers 16 years of age during their first 18 months of independent driving. It consisted of cameras, sensors (accelerometers, GPS, yaw, front radar, lane position, and various sensors obtained via the vehicle network), and a computer with removable hard drive. Data on the driving of participating parents was also collected when they drove the instrumented vehicle.

Findings

The primary findings after 18 months included the following: (1) crash and near-crash rates among teenage participants were significantly higher during the first six months of the study than the final 12 months, mirroring the national trends; (2) crash and near-crash rates were significantly higher for teenage than adult (parent) participants, also reflecting national trends; (3) teenaged driving exposure averaged between 507 and 710 km (315–441 miles) per month over the study period, but varied substantially between participants with standard errors representing 8–14 percent of the mean; and (4) crash and near-crash types were very similar for male and female teenage drivers.

Discussion

The findings are the first comparing crash and near-crash rates among novice teenage drivers with those of adults using the same vehicle over the same period of time. The finding of highly elevated crash rates of novice teenagers during the first six months of licensure are consistent with and confirm the archival crash data showing high crash risk for novice teenagers. The NTDS convenience sample of teenage drivers was similar to the US teenage driver population in terms of exposure and crash experience. The dataset is expected be a valuable resource for future in-depth analyses of crash risk, exposure to risky driving conditions, and comparisons of teenage and adult driving performance in various driving situations.     

Unsupervised driving by learner licence holders: Associated characteristics and crash risk

Aims

To determine: (a) the association between socio-demographic, and behavioural factors and compliance with supervised driving condition as a learner licensed driver, (b) whether unsupervised driving as a learner licence holder was associated with elevated crash risk while holding a learner licence.

Study design

The study population was the New Zealand Drivers Study (NZDS) cohort, a prospective cohort study designed to explore the relationship between a comprehensive range of driving and traffic safety related factors and subsequent traffic crashes and convictions among newly licensed drivers.

Results

Thirty-one percent of the study sample was non-compliant at least once with the supervised driving condition. Many socio-demographic and behavioural risk factors were independently associated with unsupervised driving. The strength of the associations was greatest for those with relatively high levels of unsupervised driving (13+ trips). High distance driven showed the strongest relationship: RR 8.91 (95% CI 5.27–15.07). Unsupervised driving was associated with increased risk of crash: 1–12 trips: RR 1.84 (1.29–2.61), and 13+ trips: RR 2.71 (1.94–3.80).Given that a significant portion of learner licence holders report driving unsupervised and those that violate this condition the most are more likely to crash, evaluation of strategies designed at improving compliance with learner licence supervised driving condition should be a research priority.     

Young driver licensing: Examination of population-level rates using New Jersey’s state licensing database

Recent surveys have provided insight on the primary reasons why US teens delay licensure but are limited in their ability to estimate licensing rates and trends. State administrative licensing data are the ideal source to provide this information but have not yet been analyzed for this purpose. Our objective was to analyze New Jersey’s (NJ) licensing database to: (1) describe population-based rates of licensure among 17- to 20-year-olds, overall and by gender and zip code level indicators of household income, population density, and race/ethnicity; and (2) examine recent trends in licensure. We obtained records on all licensed NJ drivers through June 2012 from the NJ Motor Vehicle Commission’s licensing database and determined each young driver’s age at the time of intermediate and full licensure. Data from the US Census and American Community Survey were used to estimate a fixed cohort of NJ residents who turned 17 years old in 2006–2007 (n = 255,833). Licensing data were used to estimate the number of these drivers who obtained an intermediate license by each month of age (numerators) and, among those who obtained an intermediate license, time to graduation to full licensure. Overall, 40% of NJ residents—and half of those who ultimately obtained a license by age 21—were licensed within a month of NJ’s minimum licensing age of 17, 64% by their 18th birthday, and 81% by their 21st birthday. Starkly different patterns of licensure were observed by socioeconomic indicators; for example, 65% of 17-year-olds residing in the highest-income zip codes were licensed in the first month of eligibility compared with 13% of residents living in the lowest-income zip codes. The younger an individual obtained their intermediate license, the earlier they graduated to a full license. Finally, the rate and timing of licensure in NJ has been relatively stable from 2006 to 2012, with at most a 1–3% point decline in rates. These findings support the growing body of literature suggesting that teens delay licensure primarily for economic reasons and that a substantial proportion of potentially high-risk teens may be obtaining licenses outside the auspices of a graduated driver licensing system. Finally, our finding of a relatively stable trend in licensure in recent years is in contrast to national-level reports of a substantial decline in licensure rates.     

Effects of graduated driver licensing on licensure and traffic injury rates in Upstate New York

Objective

In 2003, New York State implemented an enhanced graduated driving licensing (GDL) program that requires extended supervised driving and a passenger restriction. This study examines its safety benefit in 55 Upstate New York counties.

Methods

We analyzed fatal/incapacitating traffic injury data among 16-, 17- and 21-24-year olds for the years 2001 and 2005 using the negative binomial model. To adjust for trends in the traffic injury rate, the relative rate ratio (rRR) of 16- and 17-year olds relative to 21-24-year olds was estimated.

Results

GDL implementation was associated with a 31% reduction in the driver injury rate (rRR 0.69, 95% confidence interval (CI) 0.49-0.96), but not with any statistically significant change in the passenger injury rate (rRR 1.19, 95% CI 0.77-1.84), or pedestrian and bicyclist injury rate (rRR 1.53, 95% CI 0.89-2.62) among 16-year olds. Sixteen-year olds experienced a 21% decline in licensure rates between 2001 and 2005. GDL implementation had no appreciable impact on driver injury and licensure rates for 17- and 21-24-year olds.

Conclusions

GDL implementation is associated with a significant reduction in licensure and driver injury rate among 16-year olds. GDL implementation does not have a statistically significant impact on passenger, pedestrian, and bicyclist injury rates for 16-year olds.     

Long-term effect of the North Carolina graduated driver licensing system on licensed driver crash incidence: A 5-year survival analysis

Several studies document the success of graduated driver licensing (GDL) systems in reducing young teen crash rates, but it is not yet clear whether any portion of the crash reduction is achieved by producing more capable drivers. The purpose of this study was to determine whether young teen drivers licensed under the North Carolina GDL system remain crash-free longer than those licensed prior to GDL, independent of the crude reductions in exposure (i.e., decreasing and delaying licensure) that may be responsible for most documented effects of GDL. Survival analysis was used to compare retrospective cohorts of 16–17 year olds before (n = 105,569) and after (n = 327,054) the North Carolina GDL system was implemented. The crash incidence of GDL-licensed 16–17 year olds (combined) was 10% lower than that for pre-GDL teens for at least 5 years after being licensed to drive independently (hazard ratio [HR] = 0.90; 95% confidence interval [CI] = 0.89, 0.91). However, more refined analysis revealed the reductions to only be among females (7%; HR = 0.93; CI = 0.91, 0.94) and males (15%; HR = 0.85, CI = 0.84, 0.87) licensed at age 16 and not among females (0%; HR = 1.00; CI = 0.95, 1.06) and males (0%; HR = 1.00; CI = 0.92, 1.09) licensed at age 17. Sixteen-year-old drivers licensed under the North Carolina GDL system experienced lower first-crash incidence during the first 5 years of unsupervised driving than did those licensed under the previous system. The benefits are greater for males, who tend to have higher crash rates. The findings contradict conventional wisdom that the entire benefit of GDL results merely from decreasing or delaying licensure among young drivers.     

Young novice drivers and the risky behaviours of parents and friends during the Provisional (intermediate) licence phase: A brief report

Purpose

While there is research indicating that many factors influence the young novice driver's increased risk of road crash injury during the earliest stages of their independent driving, there is a need to further understand the relationship between the perceived risky driving behaviour of parents and friends and the risky behaviour of drivers with a Provisional (intermediate) licence.

Method

As part of a larger research project, 378 drivers aged 17–25 years (M = 18.22, SD = 1.59, 113 males) with a Provisional licence completed an online survey exploring the perceived riskiness of their parents’ and friends’ driving, and the extent to which they pattern (i.e. base) their driving behaviour on the driving of their parents and friends.

Results

Young drivers who reported patterning their driving on their friends, and who reported they perceived their friends to be risky drivers, reported more risky driving. The risky driving behaviour of young male drivers was associated with the perceived riskiness of their fathers’ driving, whilst for female drivers the perceived riskiness of their mothers’ driving approached significance.

Conclusions

The development and application of countermeasures targeting the risky behaviour of same-sex parents appears warranted by the robust research findings. In addition, countermeasures need to encourage young people in general to be non-risky drivers; targeting the negative influence of risky peer groups specifically. Social norms interventions may minimise the influence of potentially-overestimated riskiness.     

Graduated driver license nighttime compliance in U.S. teen drivers involved in fatal motor vehicle crashes

Background

Examination of teen driver compliance with graduated driver licensing (GDL) laws could be instrumental in identifying factors associated with persistently high motor vehicle mortality rates.

Methods

Fatality analysis reporting system (FARS) data from the years 2006 to 2009 were used in this nation-wide cross-sectional study of drivers covered by a state nighttime GDL law (n = 3492). A new definition of weekend, based on the school night in relation to the teenage social landscape, redefined Friday night as a weekend night and Sunday night as a weekday/school night and compared it to previous weekend definitions. Multiple logistic regression was used to examine independent effects of demographic, behavioral, environmental, contextual, and other factors on compliance with nighttime GDL laws. All analyses were performed in Stata version 11.

Results

Given coverage under nighttime GDL laws, drivers aged 15–17 years were non-compliant in 14.9% of the fatal MVCs in which they were involved, and nearly one-fifth (18.8%) of all fatalities aged 15–17 years were associated with non-compliance. Mortality risk was 10% higher using a revised social (school night) versus traditional (Sat–Sun) weekend definitions. In multivariable analysis, drivers non-compliant with nighttime GDL laws were more likely to be drinking (OR = 4.97, 3.85–6.40), unbelted (OR = 1.58, 1.25–1.99), driving on the weekend (OR = 1.82, 1.47–2.24), and killed (OR = 1.31, 1.04–1.65).

Conclusion

GDL non-compliance contributes to teen motor vehicle mortality. Legislative and enforcement efforts targeting non-school night driving, seatbelt nonuse and alcohol have potential to further reduce teen driving mortality.     

Older drivers’ crashes in Queensland,Australia

Background

The growing proportion of older adults in Australia is predicted to comprise 23% of the population by 2030. Accordingly, an increasing number of older drivers and fatal crashes of these drivers could also be expected. While the cognitive and physiological limitations of ageing and their road safety implications have been widely documented, research has generally considered older drivers as a homogeneous group. Knowledge of age-related crash trends within the older driver group itself is currently limited.

Objective

The aim of this research was to identify age-related differences in serious road crashes of older drivers. This was achieved by comparing crash characteristics between older and younger drivers and between sub-groups of older drivers. Particular attention was paid to serious crashes (crashes resulting in hospitalisation and fatalities) as they place the greatest burden on the Australian health system.

Method

Using Queensland Crash data, a total of 191,709 crashes of all-aged drivers (17–80+) over a 9-year period were analysed. Crash patterns of drivers’ aged 17–24, 25–39, 40–49, 50–59, 60–69, 70–79 and 80+ were compared in terms of crash severity (e.g., fatal), at fault levels, traffic control measures (e.g., stop signs) and road features (e.g., intersections). Crashes of older driver sub-groups (60–69, 70–79, 80+) were also compared to those of middle-aged drivers (40–49 and 50–59 combined, who were identified as the safest driving cohort) with respect to crash-related traffic control features and other factors (e.g., speed). Confounding factors including speed and crash nature (e.g., sideswipe) were controlled for.

Results and discussion

Results indicated that patterns of serious crashes, as a function of crash severity, at-fault levels, road conditions and traffic control measures, differed significantly between age groups. As a group, older drivers (60+) represented the greatest proportion of crashes resulting in fatalities and hospitalisation, as well as those involving uncontrolled intersections and failure to give way. The opposite was found for middle-aged drivers, although they had the highest proportion of alcohol and speed-related crashes when compared to older drivers. Among all older drivers, those aged 60–69 were least likely to be involved in or the cause of crashes, but most likely to crash at interchanges and as a result of driving while fatigued or after consuming alcohol. Drivers aged 70–79 represented a mid-range level of crash involvement and culpability, and were most likely to crash at stop and give way signs. Drivers aged 80 years and beyond were most likely to be seriously injured or killed in, and at-fault for, crashes, and had the greatest number of crashes at both conventional and circular intersections. Overall, our findings highlight the heterogeneity of older drivers’ crash patterns and suggest that age-related differences must be considered in measures designed to improve older driver safety.     

Declines in fatal crashes of older drivers: changes in crash risk and survivability

Objectives

Previous research has found that older driver fatal crash involvement rates per licensed driver declined substantially in the United States during 1997–2006 and declined much faster than the rate for middle-age drivers. The current study examined whether the larger-than-expected decline for older drivers extended to nonfatal crashes and whether the decline in fatal crash risk reflects lower likelihood of crashing or an improvement in survivability of the crashes that occur.

Methods

Trends in the rates of passenger vehicle crash involvements per 100,000 licensed drivers for drivers 70 and older (older drivers) were compared with trends for drivers ages 35–54 (middle-age drivers). Fatal crash information was obtained from the Fatality Analysis Reporting System for years 1997–2008, and nonfatal crash information was obtained from 13 states with good reporting information for years 1997–2005. Analysis of covariance models compared trends in annual crash rates for older drivers relative to rates for middle-age drivers. Differences in crash survivability were measured in terms of the odds of fatality given a crash each year, and the historical trends for older versus middle-age drivers were compared.

Results

Fatal crash involvement rates declined for older and middle-age drivers during 1997–2008 (1997–2005 for the 13 state subsample), but the decline for drivers 70 and older far exceeded the decline for drivers ages 35–54 (37 versus 23 percent, nationally; 22 versus 1 percent, 13 states). Nonfatal injury crash involvement rates showed similarly larger-than-expected declines for older drivers in the 13 state subsample, but the differences were smaller and not statistically significant (27 percent reduction for older drivers versus 16 percent for middle-age drivers). Property-damage-only crash involvement rates declined for older drivers (10 percent) but increased for middle-age drivers (1 percent). In 1997, older drivers were 3.5 times more likely than middle-age drivers to die in police-reported crashes (6.2 versus 1.8 deaths per 1000 crashes), but this difference was reduced during the 9-year study period to 2.9 times, as the rate of older drivers dying in a crash declined (5.5 deaths per 1000 crashes in 2005) and the death risk remained relatively stable for middle-age drivers.

Conclusions

Contrary to expectations based on increased licensure and travel by older drivers, their fatal crash risk has declined during the past decade and has declined at a faster rate than for middle-age drivers. The decreased risk for older drivers appears to extend not only to nonfatal injury crashes but also to property-damage-only crashes, at least as reported to police in the 13 states included in the nonfatal injury analysis. Although insurance collision data suggest that overall crash risk of older drivers may not be changing relative to middle-age drivers, the current analysis indicates that the reduced fatality risk of older drivers reflects both less likelihood of being involved in a police-reported crash and greater likelihood that they will survive when they do crash.     

The impact of changes to the graduated driver licensing program in Queensland, Australia on the experiences of Learner drivers

Purpose

Graduated driver licensing (GDL) has been introduced in numerous jurisdictions in Australia and internationally in an attempt to ameliorate the significantly greater risk of death and injury for young novice drivers arising from road crashes. The GDL program in Queensland, Australia, was extensively modified in July 2007. This paper reports the driving and licensing experiences of Learner drivers progressing through the current-GDL program, and compares them to the experiences of Learners who progressed through the former-GDL program.

Method

Young drivers (n = 1032, 609 females, 423 males) aged 17–19 years (M = 17.43, SD = 0.67) were recruited as they progressed from a Learner to a Provisional driver's licence. They completed a survey exploring their sociodemographic characteristics, driving and licensing experiences as a Learner. Key measures for a subsample (n = 183) of the current-GDL drivers were compared with the former-GDL drivers (n = 149) via t-tests and chi-square analyses.

Results

As expected, Learner drivers progressing through the current-GDL program gained significantly more driving practice than those in the former program, which was more likely to be provided by mothers than in the past. Female Learners in the current-GDL program reported less difficulty obtaining supervision than those in the former program. The number of attempts needed to pass the practical driving assessment did not change, nor did the amount of professional supervision. The current-GDL Learners held their licence for a significantly longer duration than those in the former program, with the majority reporting that their Logbook entries were accurate on the whole. Compared to those in the former program, a significantly smaller proportion of male current-GDL Learners reported being detected for a driving offence whilst the females reported significantly lower crash involvement. Most current-GDL drivers reported undertaking their supervised practice at the end of the Learner period.

Conclusions

The enhancements to the GDL program in Queensland appear to have achieved many of their intended results. The current-GDL Learners participating in the study reported obtaining a significantly greater amount of supervised driving experience compared to former-GDL Learners. Encouragingly, the current-GDL Learners did not report any greater difficulty in obtaining supervised driving practice, and there was a decline in the proportion of current-GDL Learners engaging in unsupervised driving. In addition, the majority of Learners do not appear to be attempting to subvert logbook recording requirements, as evidenced by high rates of self-reported logbook accuracy. The results have implications for the development and the evaluation of GDL programs in Australia and around the world.