Potential benefits of restrictions on the transport of teenage passengers by 16 and 17 year old drivers

Effectiveness of road safety interventions: An evidence and gap map

Background

Road Traffic injuries (RTI) are among the top ten leading causes of death in the world resulting in 1.35 million deaths every year, about 93% of which occur in low- and middle-income countries (LMICs). Despite several global resolutions to reduce traffic injuries, they have continued to grow in many countries. Many high-income countries have successfully reduced RTI by using a public health approach and implementing evidence-based interventions. As many LMICs develop their highway infrastructure, adopting a similar scientific approach towards road safety is crucial. The evidence also needs to be evaluated to assess external validity because measures that have worked in high-income countries may not translate equally well to other contexts. An evidence gap map for RTI is the first step towards understanding what evidence is available, from where, and the key gaps in knowledge.

Objectives

The objective of this evidence gap map (EGM) is to identify existing evidence from all effectiveness studies and systematic reviews related to road safety interventions. In addition, the EGM identifies gaps in evidence where new primary studies and systematic reviews could add value. This will help direct future research and discussions based on systematic evidence towards the approaches and interventions which are most effective in the road safety sector. This could enable the generation of evidence for informing policy at global, regional or national levels.

Search Methods

The EGM includes systematic reviews and impact evaluations assessing the effect of interventions for RTI reported in academic databases, organization websites, and grey literature sources. The studies were searched up to December 2019.

Selection Criteria

The interventions were divided into five broad categories: (a) human factors (e.g., enforcement or road user education), (b) road design, infrastructure and traffic control, (c) legal and institutional framework, (d) post-crash pre-hospital care, and (e) vehicle factors (except car design for occupant protection) and protective devices. Included studies reported two primary outcomes: fatal crashes and non-fatal injury crashes; and four intermediate outcomes: change in use of seat belts, change in use of helmets, change in speed, and change in alcohol/drug use. Studies were excluded if they did not report injury or fatality as one of the outcomes.

Data Collection and Analysis

The EGM is presented in the form of a matrix with two primary dimensions: interventions (rows) and outcomes (columns). Additional dimensions are country income groups, region, quality level for systematic reviews, type of study design used (e.g., case-control), type of road user studied (e.g., pedestrian, cyclists), age groups, and road type. The EGM is available online where the matrix of interventions and outcomes can be filtered by one or more dimensions. The webpage includes a bibliography of the selected studies and titles and abstracts available for preview. Quality appraisal for systematic reviews was conducted using a critical appraisal tool for systematic reviews, AMSTAR 2.

Main Results

The EGM identified 1859 studies of which 322 were systematic reviews, 7 were protocol studies and 1530 were impact evaluations. Some studies included more than one intervention, outcome, study method, or study region. The studies were distributed among intervention categories as: human factors (n = 771), road design, infrastructure and traffic control (n = 661), legal and institutional framework (n = 424), post-crash pre-hospital care (n = 118) and vehicle factors and protective devices (n = 111). Fatal crashes as outcomes were reported in 1414 records and non-fatal injury crashes in 1252 records. Among the four intermediate outcomes, speed was most commonly reported (n = 298) followed by alcohol (n = 206), use of seatbelts (n = 167), and use of helmets (n = 66). Ninety-six percent of the studies were reported from high-income countries (HIC), 4.5% from upper-middle-income countries, and only 1.4% from lower-middle and low-income countries. There were 25 systematic reviews of high quality, 4 of moderate quality, and 293 of low quality.

Authors' Conclusions

The EGM shows that the distribution of available road safety evidence is skewed across the world. A vast majority of the literature is from HICs. In contrast, only a small fraction of the literature reports on the many LMICs that are fast expanding their road infrastructure, experiencing rapid changes in traffic patterns, and witnessing growth in road injuries. This bias in literature explains why many interventions that are of high importance in the context of LMICs remain poorly studied. Besides, many interventions that have been tested only in HICs may not work equally effectively in LMICs. Another important finding was that a large majority of systematic reviews are of low quality. The scarcity of evidence on many important interventions and lack of good quality evidence-synthesis have significant implications for future road safety research and practice in LMICs. The EGM presented here will help identify priority areas for researchers, while directing practitioners and policy makers towards proven interventions.

How many crashes are caused by driver interaction with passengers? A meta-analysis approach

INTRODUCTION

Conversation and other interactions with passengers while driving induce a level of distraction to the person driving.

METHOD

This paper conducts a qualitative literature review on the effect of passenger interaction on road safety and then extends it by using meta-analysis techniques.

RESULTS

The literature review indicates that the distraction due to passengers is a very frequent risk factor, with detrimental effects to various driving behavior and safety measures (e.g., slower reaction times to events, increased severity of injuries in crashes), associated with non-negligible proportions of crashes. Particular issues concern the effect of passenger age (children, teenagers) on which the literature is inconclusive. Existing studies vary considerably in terms of study methods and outcome measures. Nevertheless, a meta-analysis could be carried out regarding the proportion of crashes caused by this distraction factor. The selection of studies for the meta-analysis was based on a rigorous method including specific study selection criteria. The findings of the random-effects meta-analyses that were carried out showed that driver interaction with passengers causes a non-negligible proportion of road crashes, namely 3.55% of crashes regardless of the age of the passengers and 3.85% when child and teen passengers are excluded. Both meta-estimates were statistically significant, revealing the need for further research, especially considering the role of passenger age.

PRACTICAL APPLICATIONS

Stakeholders could make good estimates on future crash numbers and causes and take action in order to counter the effects of passenger interaction.

Brief Report: The Association of Graduated Driver Licensing with Nondriver Transport-related Injuries Among Adolescents

BACKGROUND

As a phased approach to initiating driving, graduated driver licensing restricts driving by young drivers with the aim of reducing crashes. It might increase riding with parents or on buses, which might be safer, or walking or biking, which might be more dangerous. We examined whether it increases nondriver injuries, and whether it reduces total injuries combining drivers and nondrivers.

METHODS

We conducted longitudinal analyses of 1995-2012 traffic injuries from 43 states. Using Poisson mixed regression, we estimated adjusted rate ratios for visible, incapacitating, and fatal injury.

RESULTS

Among 16 year olds, graduated driver licensing was associated with reduced passenger injuries (adjusted rate ratio 0.93, 95% confidence interval: 0.89, 0.97). It was not associated with increased injuries as bus riders, pedestrians, or bicyclists among 16- or 17-year olds. It was associated with a 10% reduction in total injuries among 16-year olds, but not 17-year olds.

CONCLUSION

Graduated driver licensing was associated with reduced passenger injuries and total injuries.

Graduated driver licensing and differential deterrence: The effect of license type on intentions to violate road rules

In keeping with the differential deterrence theory, this article assesses the moderating effect of license type on the relationship between social control and intention to violate road rules. More precisely, the article has two objectives: (1) to assess the effect of license type on intentions to infringe road rules; and (2) to pinpoint mechanisms of social control affecting intentions to violate road rules based on one's type of driver license (a restricted license or a full license). This effect is examined among a sample of 392 young drivers in the province of Quebec, Canada. Drivers taking part in the Graduated Driver Licensing (GDL) program have limited demerit points and there is zero tolerance for drinking-and-driving. Propensity score matching techniques were used to assess the effect of the license type on intentions to violate road rules and on various mechanisms of social control. Regression analyses were then conducted to estimate the moderating effect of license type. Average treatment effects from propensity score matching analyses indicate that respondents with a restricted license have lower levels of intention to infringe road rules. While moral commitment and, to a lesser extent, the perceived risk of arrest are both negatively associated with intentions to violate road rules, the license type moderates the relationship between delinquent peers and intentions to violate road rules. The effect of delinquent peers is reduced among respondents with a restricted driver license. Finally, a diminished capability to resist peer pressure could explain the increased crash risk in months following full licensing.

Racing with friends: Resistance to peer influence, gist and specific risk beliefs

PURPOSE

Studies assessing young drivers' risk appraisals with their driving behavior have shown both positive and inverse associations, possibly due to differences in survey items that cue gist appraisals about risk (i.e., beliefs that are focused on meaning) or specific appraisals (i.e., beliefs that are focused on discrete instances). Prior research has indicated that gist-based reasoning is protective against engaging in risk behavior and that use of gist appraisals increases with development. Additionally, although much of adolescents' risk-taking occurs in groups, almost no research examines how adolescents' resistance to peer influence may relate to their specific and gist beliefs about socially-bound risk behavior, as well as their future engagement in such behavior.

METHODS

One hundred and thirty-two adolescent drivers participated in a prospective self-report study on racing behavior. Surveys measured specific and gist risk appraisals, resistance to peer influence, and racing behavior at two time points three months apart. We hypothesized that stronger specific appraisals would be associated with greater likelihood of racing, and stronger gist appraisals would be protective. Further, we hypothesized that resistance to peer influence would be positively associated with gist appraisals and negatively associated with specific risk appraisals; and would also be inversely associate with racing.

RESULTS

Specific risk appraisals and gist appraisals were predictive of racing behavior as hypothesized. Resistance to peer influence did not predict racing, but was associated with each type of risk appraisal as predicted at Time 1, although the association between specific risk and resistance to peer influence was non-significant at the second time point.

CONCLUSIONS

Gist beliefs and the ability to resist influence from friends might be indicative of an underlying strength of one's own beliefs about the self as a non-risk taking person who stands up for his or her beliefs, which is protective against engaging in risky behavior, such as racing with friends.

The association between graduated driver licensing laws and travel behaviors among adolescents: an analysis of US National Household Travel Surveys

Background

Young novice drivers have crash rates higher than any other age group. To address this problem, graduated driver licensing (GDL) laws have been implemented in the United States to require an extended learner permit phase, and create night time driving or passenger restrictions for adolescent drivers. GDL allows adolescents to gain experience driving under low-risk conditions with the aim of reducing crashes. The restricted driving might increase riding with parents or on buses, which might be safer, or walking or biking, which might be more dangerous. We examined whether GDL increases non-driver travels, and whether it reduces total travels combining drivers and non-drivers.

Methods

We used data from the US National Household Travel Survey for the years 1995–1996, 2001–2002, and 2008–2009 to estimate the adjusted ratio for the number of trips and trip kilometers made by persons exposed to a GDL law, compared with those not exposed.

Results

Adolescents aged 16 years had fewer trips and kilometers as drivers when exposed to a GDL law: ratio 0.84 (95 % confidence interval (CI) 0.71, 1.00) for trips; 0.79 (0.63, 0.98) for kilometers. For adolescents aged 17 years, the trip ratio was 0.94 (0.83, 1.07) and the kilometers ratio 0.80 (0.63, 1.03). There was little association between GDL laws and trips or kilometers traveled by other methods: ratio 1.03 for trips and 1.00 for kilometers for age 16 years, 0.94 for trips and 1.07 for kilometers for age 17.

Conclusions

If these associations are causal, GDL laws reduced driving kilometers by about 20 % for 16 and 17 year olds, and reduced the number of driving trips by 16 % among 16 year olds. GDL laws showed little relationship with trips by other methods.

Association of Graduated Driver Licensing With Driver, Non-Driver, and Total Fatalities Among Adolescents

INTRODUCTION

Graduated driver licensing systems typically require an extended learner permit phase, and create night-time driving or passenger restrictions for adolescent drivers. Restricted driving might increase the use of alternative transportation to replace driving and consequently increase crashes and injuries for passengers, bus riders, pedestrians, and bicyclists. This study examined whether graduated driver licensing increases non-driver fatalities among adolescents, and whether it reduces total traffic fatalities combining drivers and non-drivers.

METHODS

Longitudinal analyses were conducted using data from the 1995-2012 U.S. Fatality Analysis Reporting System. Adjusted rate ratios were estimated for being fatally injured in a crash according to: (1) presence/absence of a graduated driver licensing system; and (2) four levels of graduated driver licensing systems (absent, weak, medium, strong). Analyses were conducted in 2015.

RESULTS

Among adolescents aged 16 years, graduated driver licensing was not associated with increased passenger fatalities (adjusted rate ratio, 0.96; 95% CI=0.90, 1.03) or pedestrian and bicyclist fatalities (adjusted rate ratio, 1.09; 95% CI=0.85, 1.39), but was associated with an 11% reduction in total traffic fatalities. Among those aged 17 years, graduated driver licensing was not associated with increased fatalities as passengers, pedestrians, or bicyclists, and was not associated with reduced total traffic fatalities.

CONCLUSIONS

In general, graduated driver licensing systems were not associated with increased fatalities as passengers, pedestrians, bicyclists, and bus riders. Graduated driver licensing systems were associated with reduced total fatalities of adolescents aged 16 years.

Long-term changes in crash rates after introduction of a Graduated Driver Licensing decal provision

BACKGROUND

New Jersey (NJ) implemented the first Graduated Driver Licensing (GDL) decal provision in the U.S. in May 2010. An initial study reported a 1-year post-decal decrease in the crash rate among NJ intermediate drivers aged <21 years. Longer-term analysis is critical for policymakers in other states considering whether to implement a decal provision.

PURPOSE

To evaluate the longer-term (2-year) effect of NJ's decal provision on overall and age-specific crash rates of young drivers with intermediate licenses.

METHODS

Monthly per-driver police-reported crash rates during January 2006-June 2012 were estimated. Specific crash types included injury, midnight-4:59am, single-vehicle, multiple-vehicle, and peer passenger crashes. Negative binomial modeling compared pre- versus post-decal crash rates, adjusting for age, gender, calendar month, gas price, and 21- to 24-year-old licensed driver crash rates; piecewise negative binomial regression models accounted for pre-decal crash trends among intermediate drivers. Analyses were conducted in 2013.

RESULTS

The adjusted crash rate for intermediate drivers was 9.5% lower in the 2-year post-decal period than the 4-year pre-decal period (95% CI=0.88, 0.93). Crash rates decreased 1.8% per year before the provision and 7.9% per year in the post-decal period (p<0.001 for difference in slopes). For several crash types, effects appeared to be particularly strong for 18- and 19-year-olds. An estimated 3,197 intermediate drivers had crashes prevented.

CONCLUSIONS

NJ's decal provision was associated with a sustained decline in intermediate driver crashes. Future research should aim to better understand the causal mechanism by which NJ's decal provision may have exerted an effect.

Factors associated with adolescents' propensity to drive with multiple passengers and to engage in risky driving behaviors

PURPOSE

Research shows that parenting factors and individual difference variables, such as sensation seeking (SS) and risk perceptions (RPs), are associated with increased motor vehicle crash risk for young drivers. The presence of peer passengers is also known to be associated with increased crash risk. However, as previous studies did not study these factors concurrently, less is known about the factors that are associated with driving with peer passengers and if peer passengers may mediate the effect of parenting and individual difference variables on adolescents' engagement in risky driving behavior.

METHODS

We examined predictors of driving with multiple passengers (DWMPs) and explored it as a potential mediator of pathways from three factors: (1) SS, (2) RPs, and (3) Parental monitoring and rule-setting to risky driving behaviors in a convenience sample of 198 adolescent drivers using a cross-sectional Web-based survey.

RESULTS

Findings indicate that both stronger RPs and perceiving parents as strong monitors and rule setters were associated with less engagement in risky driving, whereas greater SS was associated with more engagement in risky driving; RPs, monitoring, and SS were also significantly associated with DWMPs in these same directions. DWMPs partially mediated the effect of these risk factors on risky driving behavior.

CONCLUSIONS

Results inform theory and policy by examining factors associated with risk taking in the context of adolescent driving. Interventions can be developed to complement graduated driver licensing laws by targeting individual difference variables and decreasing opportunities for peer passenger carriage.

National evaluation of the effect of graduated driver licensing laws on teenager fatality and injury crashes

PROBLEM

Automobile crashes remain a prominent cause of death and injury for teenagers in the United States. While it is generally agreed that graduated drivers licensing (GDL) influences crash rates, it is unclear which components have the strongest effect on any specific types of crashes.

METHOD

We analyze the relative effect of different stages of GDL on teenage fatal and injury crash risk via a negative binomial generalized linear model with random state effects. Overall, nighttime, and crashes with multiple teenage passengers are considered.

RESULTS

The strongest effects are seen by 16-year-olds, for which a strict permit stage is associated with a 58% reduction in fatal crash risk over a lenient permit stage. Similar reductions are seen for injury crashes. The intermediate stage, involving nighttime and passenger restrictions, is associated with a 44% reduction in fatalities but has relatively little effect on injury crashes. The strongest effects are generally seen for passenger crashes, followed by nighttime, and then overall crashes.

IMPACT ON INDUSTRY

This study identifies stronger relationships between GDL and crash risk than has previously been discovered and captures the relative effects of permit and intermediate licensing restrictions, two high-level components of GDL which differ in intent and implementation.

The Influence of Passengers on Older Drivers Involved in Fatal Crashes

The authors examined if the presence of passengers affects the risk of making unsafe actions among older drivers, and determined what specific types of unsafe actions may be affected (positively or adversely) by the presence of passengers. They used 1975 to 1998 data from the U.S. Fatality Analysis Reporting System (FARS); unsafe actions were based on driver-related factors. The authors calculated the odds ratio (OR) of making unsafe driving actions in the presence of passengers compared to situations where drivers were alone. In general, the presence of passengers was beneficial to older drivers (e.g., for drivers aged 65 to 79 with four or more passengers, OR = 0.73 [99% Confidence interval[CI] = 0.61, 0.86. For drivers aged 65 to 79, the presence of passengers was associated with a reduced risk of some unsafe actions (e.g., driving the wrong way, OR = 0.37 [95% CI = 0.30, 0.46]) but a higher risk of other actions (e.g., ignoring signs/warnings/right of way, OR = 1.18 [95% CI = 1.15, 1.22]). These findings are discussed in the context of strategies to maximize safe driving in older adults.

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.

The influence of driver distraction on the severity of injuries sustained by teenage drivers and their passengers

Studies show that teenage drivers are at a higher risk for crashes. Opportunities to engage in technology and non-technology based distractions appear to be a particular concern among this age group. An ordered logit model was developed to predict the likelihood of a severe injury for these drivers and their passenger using a national crash database (the 2003, U.S. DOT-General Estimate System [GES]). As one would expect, speeding substantially increases the likelihood of severe injuries for teenage drivers and their passengers. The results of the analysis also reveal that teenage drivers have an increased likelihood of more severe injuries if distracted by a cell phone or by passengers than if the source of distraction was related to in-vehicle devices or if the driver was inattentive. Additionally, passengers of teenage drivers are more likely to sustain severe injuries when their driver is distracted by devices or passengers than with a non-distracted or inattentive driver. This supports the previous literature on teenage drivers and extends our understanding of injuries for this age group related to distraction-related crashes.

Evaluation of the health effects of the new driving penalty point system in the Lazio Region, Italy, 2001-4

OBJECTIVE

The penalty point system was introduced in Italy in June 2003. The aim of this study was to evaluate the health effects of this legislation in the Lazio region.

METHODS

Poisson models were used to compare emergency department visits, hospitalizations and death between the pre-law and post-law periods (July 2001-June 2003; July 2003-June 2004).

RESULTS

The emergency department visit rate ratio (RR) of the two periods was 0.87 (95% confidence interval (CI) 0.86 to 0.88); the corresponding hospital admission RR was 0.87 (95% CI 0.84 to 0.9). The death RR was 0.93 (95% CI 0.82 to 1.05).

CONCLUSION

After the legislation was introduced, there were fewer visits to the emergency department, hospitalizations and death from road traffic injuries. However, the effect was lower than expected, and it decreased over time.

Passenger effects on teenage driving and opportunities for reducing the risks of such travel

OBJECTIVES

To review the research evidence concerning the effects of passengers on teenage driving and crash involvement, and to explore ways to reduce negative effects.

METHODS

Review of the international literature on these topics.

RESULTS

Passenger presence increases crash risk for teenage drivers, especially when the passengers are other teenagers and especially when they are male. Female passengers do not have the same effects. Teenagers are more susceptible to peer influences than adults. The combination of passenger-induced distraction and driving inexperience can disrupt driving behavior, and there is evidence that teenage driver risk taking increases in vehicles with multiple teenagers. Possible ways to reduce the resulting crash problem include altering the in-vehicle behavior of teenagers or influencing their selection of travel partners. Legal restrictions on passengers with teenage drivers have been found effective in reducing the crash problem. Parental monitoring of teenage driving behavior, and programs aimed at teenagers themselves, could be other options but their efficacy is unproven. It currently is unknown why female passengers have a different effect than males or if that might offer clues about future interventions.

CONCLUSIONS

Despite passenger restrictions in the majority of states, 42% of 16- and 17-year-old drivers in fatal crashes in 2005 were transporting teenagers with no adults in the vehicle; 61% of teenage passenger deaths (1,222 in 2005) occurred in vehicles driven by other teenagers. Wider application of passenger restrictions is indicated.

IMPACT ON INDUSTRY

Ways to make passenger restrictions more effective are needed, and other techniques for reducing this major problem need development and testing.

Contribution of the components of graduated licensing to crash reductions

PROBLEM

It has been established that graduated licensing systems lead to crash reductions among beginning drivers. What is the contribution of the various components of graduated licensing to these reductions, and how can their effectiveness be increased?

METHOD

Literature review and synthesis.

RESULTS

Extended learner periods, nighttime restrictions, and passenger restrictions have contributed to crash reductions. Presently there is insufficient evidence concerning the contribution of seat belt or cell phone provisions, or contingent advancement penalties.

DISCUSSION

There is more to learn about graduated licensing and its component features. However, there are ways to increase the contribution of all the components through stronger laws and greater compliance. With the right kind of community commitment and focus, substantial further reductions in young driver crashes are achievable.

IMPACT ON INDUSTRY

The results can guide states in establishing graduated licensing systems that maximize crash reductions.

"Banned from the streets I have paid to use": an analysis of Australian print media coverage of proposals for passenger and night driving restrictions for young drivers

OBJECTIVE

To catalogue arguments that can be anticipated in public debate when passenger and night driving restrictions are being advocated.

DESIGN AND SETTING

Frame analysis of all relevant coverage of these topics in Australian print media during the three month period between June and September 2004 when intensive debate on the topic occurred.

MAIN OUTCOME MEASURES

Debating frames used in reports and commentary on passenger and night driving restrictions.

RESULTS

There were 52 relevant articles published containing seven distinct frames supporting the restrictions and six opposing them. Overall, more instances of frames supporting the restrictions were published; these mostly focused on the potential for saving lives. Opposition to the restrictions focused largely on their inappropriateness as a road safety measure as well as on the importance of young people's autonomy and freedom.

CONCLUSIONS

Advocates of passenger and night driving restrictions have a number of arguments available to advance their case; however, it is important to anticipate and address possible counter arguments. Future research should address the saliency of different arguments to the public and key decision makers in government.

Fatal crashes involving young unlicensed drivers in the U.S

INTRODUCTION

Young unlicensed drivers' involvement in fatal crashes is a recurrent problem in the United States.

METHODS

This descriptive study extracted cross-sectional data on fatal crashes from the Fatality Analysis Reporting System from 1998 to 2002. Young unlicensed driver fatal crashes are examined by age, gender, and region.

RESULTS

There were 2,452 young unlicensed driver fatal crashes representing 10.8% of all young drivers' fatal crashes. By age, 72.5% are over 15 years, males are involved in 74.5%, and southern and western states have a higher percent of young unlicensed driver fatal crashes.

CONCLUSIONS

Subgroups of young people based on their age, gender, and region are over-represented in fatal crashes as unlicensed drivers. Further studies are needed to investigate the context and factors of young unlicensed drivers, essential to tailor interventions.

IMPACT ON INDUSTRY

Young unlicensed drivers circumvent the established licensing process and pose a serious threat to themselves and other road users.

Teen drivers and the risk of injury to child passengers in motor vehicle crashes

OBJECTIVES

The first aim was to examine the relationship between driver's age (novice teens, older teens, and adults) and child passenger's restraint status, front row seating, and injury risk. The second aim was to explore whether there was an excess injury risk to child passengers in teen crashes compared to those in adult crashes by examining the contributing factors.

METHODS

A cross sectional study involving telephone interviews with insured drivers in a probability sample of 12 163 crashes involving 19 111 children was conducted. Sequential logistic regressions were employed.

RESULTS

Among child passengers aged 4-8, appropriate restraint was <1% for novice teens, 4.5% for older teens, and 23.6% for adults. Front row seating for children <13 years was more common in the novice teen group (26.8%) than in the other two groups. Compared with children riding with adults, those with both teen groups experienced excess injury risk. After adjusting for crash severity, there was a 43% reduction in the odds ratio (OR) for novice teens (OR 1.58, 95% confidence interval (CI) 1.14 to 2.19) and a 24% reduction for older teens (OR 2.15, 95% CI 1.42 to 3.26). After adjusting for vehicle type, child's restraint status and front row seating, there was a further 19% reduction in the OR for novice teens (OR 1.37, 95% CI 1.00 to 1.88) and a further 13% reduction for older teens (OR 1.74, 95% CI 1.14 to 2.66).

CONCLUSION

These findings suggest ways in which graduated driver licensing laws may be further enhanced to better protect child passengers from the excess injury risk associated with teen crashes.

Passenger carriage and car crash injury: a comparison between younger and older drivers

This study was conducted to investigate the effects of passenger carriage, including the number of passengers and the ages of passengers, on the risk of car crash injury. The study utilised data obtained from a case-control study conducted in the Auckland region of New Zealand between 1998 and 1999. Cases were car drivers who involved in crashes in which at least one occupant was hospitalised or killed. Controls were selected from a cluster random sample of car drivers on the roads in the same region. Self-report information on the numbers of passengers carried and their ages at the time of crash or at the time of the roadside survey, as well as potential confounding factors, was obtained from the drivers, or a proxy, using an interviewer-administered questionnaire. A total of 571 cases (93% response rate), including 195 younger drivers (aged <25 years), and 588 controls (79% response rate), including 94 younger drivers participated in the study. After adjusting for other risk factors, the odds of car crash injury among younger drivers was 15.55 times (95% CI 5.76-42.02) for those who carried two or more same age passengers, and 10.19 times (95% CI 2.84-36.65) for those who carried two or more other age passengers, compared with unaccompanied drivers. In comparison, no increase in risk was observed for older drivers who carried two or more passengers regardless of age. The carriage of two or more passengers, irrespective of the ages of passengers, significantly increases the risk of car crash injury among younger drivers. Passenger restriction as part of the graduate licensing system was discussed in the light of these results.

Nighttime driving, passenger transport, and injury crash rates of young drivers

OBJECTIVE

This study examines the association of nighttime driving and the carrying of passengers with the rate of motor vehicle crashes that resulted in severe or fatal injury to young drivers in California before the implementation of a graduated licensing system.

METHOD

Passenger vehicle drivers aged 16 or 17 involved in injury crashes in California from 1 January 1993 to 30 June 1998 were identified through a police crash database. An induced exposure method was used to estimate driving exposure. Odds ratios for driver injury crashes were estimated with logistic regression.

RESULTS

Driving at night, driving without adult supervision, driving with passengers, using alcohol, being 16, and being male were associated with high rates of driver injury crash.

CONCLUSIONS

The injury crash rate for drivers aged 16 or 17 increases during nighttime hours and in the absence of adult supervision, with or without other passengers. Driving between 10 pm and midnight is particularly dangerous for young drivers. Nighttime driving restrictions that begin at 10 pm or earlier and restrictions on carrying passengers at any hour may increase the effectiveness of graduated licensing systems.

Enhancing the effectiveness of graduated driver licensing legislation

PROBLEM

Many states have enacted graduated driver licensing (GDL) systems in an effort to reduce the very high crash rates of young beginning drivers. This article addresses how to achieve the maximum benefit from GDL by ensuring compliance with protective restrictions.

ENHANCING GDL THROUGH SYSTEM STRUCTURE

The major crash reductions due to GDL systems result from the protective restrictions during the initial two levels, which isolate novice drivers from the highest risk driving situations. Accordingly, GDL systems should include protective restrictions that adequately control the greatest dangers facing young drivers: multiple teen passengers and night driving before midnight.

ENCOURAGING COMPLIANCE THROUGH SYSTEM STRUCTURE

Including protective restrictions that are supported by parents and teens will encourage compliance. Furthermore, linking a teen's advancement through GDL to demonstrated responsible driving will likely encourage compliance more than threatening punishment for violations.

ENCOURAGING COMPLIANCE THROUGH ENFORCEMENT

Parents are in a prime position to enforce most GDL restrictions, but there is some evidence they do not enforce those restrictions that they consider too extreme. Little is currently known about the involvement of law enforcement in GDL systems, but there is potential for high visibility law enforcement activities to encourage compliance with restrictions.

IMPACT ON RESEARCH, PRACTICE, AND POLICY

There is a need for better designed GDL systems in many states; more research is needed to examine compliance with restrictions and to evaluate enforcement efforts by parents and law enforcement.