PEDIATRICS Vol. 122 No. 5 November 2008, pp. e994-e1000 (doi:10.1542/peds.2008-1257)
ARTICLE |
Unlicensed Teenaged Drivers: Who Are They, and How Do They Behave When They Are Behind the Wheel?
a Department of Biostatistics, University of Michigan School of Public Health, and Survey Methodology Program, Institute for Social Research, University of Michigan, Ann Arbor, Michigan
b Center for Injury Research and Prevention, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
c Divisions of Adolescent Medicine
d General Pediatrics, Department of Pediatrics, Leonard Davis Institute for Health Economics, and Center for Public Health Initiatives, University of Pennsylvania, Philadelphia, Pennsylvania
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ABSTRACT |
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 TOP ABSTRACT METHODSRESULTSDISCUSSIONCONCLUSIONSREFERENCES |
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OBJECTIVE. The objective of this study was to determine the prevalence and associated risk factors for unlicensed driving among 9th- through 11th-graders.
METHODS. A nationally representative school-based survey of 5665 9th-, 10th-, and 11th-graders ascertained whether students engaged in unlicensed driving and determined associated driving behaviors, risk behaviors, and demographic factors. Unlicensed driving, defined as not having any type of license and "driving on [one's] own" as opposed to learning to drive, or not driving yet was ascertained.
RESULTS. One (4.2%) in 25 US 9th- through 11th-graders reported that they drove at least 1 hour/week without a license. Unlicensed drivers were more likely to identify as being black or Hispanic, to live in rural or central city districts, and to report lower grades in school. No relationship was found between license status and reported crashes; however, unlicensed teenaged drivers were less likely to report seat belt use, more likely to report driving while under the influence of alcohol or drugs, and more likely to report more trips without a purpose. One fourth (28%) of them had taken a driver's education class, and one half (50%) reported parents as most helpful in learning to drive. Two thirds (66%) of the unlicensed drivers reported most often using a vehicle that others usually drive.
CONCLUSIONS. Considering the high burden of teen crashes, it is important to reach and deliver effective anticipatory guidance to unlicensed teenaged drivers who are at high risk for unsafe driving practices. Parents and driver's education instructors have contact with many of these unlicensed drivers. Clinicians, particularly those in rural and central city districts, should discuss unlicensed driving starting before the legal age of driving while screening for other health risk behaviors. Additional research is needed for better understanding of barriers to licensing among the teen population of licensing age.
Key Words: accident prevention • injury prevention • adolescent • unlicensed driving • survey
Abbreviations: GDL—graduated driver licensing • NYDS—National Young Driver Survey • OR—odds ratio • CI—confidence interval
Teen drivers are at high risk for motor vehicle crashes and resulting injuries and mortality.1 One in 5 9th- through 11th-grade drivers reported crash involvement in the previous year,2 and motor vehicle crashes account for >1 in 3 teen deaths in the United States.3 To address this problem, states have adopted graduated driver licensing (GDL) laws, whereby teens gradually receive increased driving privileges after acquiring experience on the road. Between 1995 and 2005, the number of teenaged drivers who died in crashes declined4 as a result of delayed licensure through GDL.1,5–9 It is not known, however, how many teens drive unlicensed and which populations are most at risk for this behavior.
Previous literature linked unlicensed drivers with higher risk for crash, injury, and mortality than licensed drivers. Blows et al10 found that crash injury risk of unlicensed drivers of any age in New Zealand was 11-fold greater than that for licensed drivers. In the United States, substantial numbers of crash fatalities involve unlicensed rural male drivers who are younger than 16.11,12 Children aged 8 to 17 have an adjusted fourfold increased risk for death when driven by someone who is younger than 16, many of whom would be unlicensed, as when driven by someone who is older than 24.13 Of 1839 drivers who were aged 14 to 18 and died in fatal crashes in 2006, 261 (14.1%) were unlicensed and 82 (4.4%) had a suspended, revoked, or expired license.14
More than 20 years ago, before current GDL was in place, Williams et al15 conducted a regional study of unlicensed teen driving. More than one third had driven with parents or other family members, and one fourth of boys and one eighth of girls had driven on their own. The only recent study of unlicensed teen driving12 examined a restrictive sample of 49 fatal crashes with drivers who were younger than 16 and involved in police pursuits between 1999 and 2003.
In 2006, as part of the National Young Driver Survey (NYDS), estimates of teen driving attitudes and behaviors were measured. The survey sample was representative of 9th-, 10th-, and 11th-graders in US public schools. Because it collected information on respondents’ license status, an updated exploration of unlicensed driving among a nationally representative sample of high school students was possible.
We hypothesized that, despite GDL implementation, unlicensed driving continues among teens and that demographic factors would predict who drives unlicensed; therefore, these analyses aim to determine the current prevalence and description of unlicensed driving among US 9th- to 11th-graders. These data can be used to inform public health, enforcement, and education campaigns to reduce illegal driving.
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METHODS |
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TOPABSTRACTMETHODSRESULTSDISCUSSIONCONCLUSIONSREFERENCES |
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Study Population and Data Collection
The NYDS was conducted in Spring 2006 with a nationally representative sample of 5665 9th, 10th-, and 11th-graders who attended 19 873 US public high schools (Fig 1). Although the survey was designed to be completed by students regardless of driving status, a section regarding driver training, behavior, and crash history was completed only by teens who were learning to drive or driving on their own. The survey used an optically scannable answer sheet. The institutional review boards of the Children's Hospital of Philadelphia and the survey contractor, Macro International, Inc (Calverton, MD), approved the survey protocol. Sample design details are available from Ginsburg et al.16
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Variable Definitions
Unlicensed driving was defined as driving "on one's own" as opposed to learning to drive or not driving yet by survey participants who reported not having a license (as opposed to those with learner permits or licenses with or without restrictions). Drivers included respondents who were "learning to drive" or "driving on one's own" at least 1 hour/week and excluded those who responded "I do not drive yet" or "drive <1 hour" weekly. Unlicensed drivers included those who reported driving unlicensed at least 1 hour/week.
Students self-reported their grade level, gender, race/ethnicity, and driver education history; alcohol use in the previous 30 days (0, 1–2, 3–5, 6–9, 10–19, 20–29, and 30 of the last 30 days); grades (mostly A's, B's, C's, D's, or E/F's); and how often (always, sometimes, rarely/never) they drove to relax, have fun, get to school or work, go shopping or do errands, go out with friends, or drive without a place to go. They were also asked who was most helpful in teaching them to drive: driver's education instructor, mother/stepmother, father/stepfather, male friend/boyfriend, female friend/girlfriend, or other family (grandmother/grandfather, brother, sister, or guardian) and whether they were the main driver of the vehicle that they drive most often.
Students reported (always/sometimes/rarely or never) on a variety of driving behaviors: seat belt use, alcohol/drug use when driving, and speeding (driving >10 mph above the limit), as well as number of hours driven per week (0, 1–2, 3–5, 6–10, or 
11), number of crashes in the previous 12 months, and number of lifetime crashes involving injury (2 categorized into a single category).
School location was categorized on the basis of zip code into 4 levels condensed from a 7-level urbanicity measure17: "central city" (large or midsize central city), "suburban" (urban fringe of large or midsized city), "town" (large or small town), and "rural."
Data Analysis
All analyses were conducted by using SAS 9.1 (SAS Institute, Inc, Cary, NC), with appropriate methods to account for the complex sample design.18,19 Logistic regression modeling results are expressed as adjusted odds ratios (ORs) with corresponding 95% confidence intervals (CIs).
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RESULTS |
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TOPABSTRACTMETHODSRESULTSDISCUSSIONCONCLUSIONSREFERENCES |
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Approximately 1 (4.2% [95% CI: 3.0%–5.5%]) in 25 US 9th- to 11th-graders reported at least some unlicensed driving. Of 3705 classified as drivers, 5.9% (95% CI: 4.0%–7.7%) were unlicensed.
Table 1 shows the distributions of demographic measures by unlicensed driving status. The unlicensed were approximately distributed evenly among 9th, 10th-, and 11th-graders (33.6%, 35.6%, and 30.7%, respectively), whereas licensed drivers were less likely to be 9th- than 10th- or 11th-graders (23.3%, 37.4%, and 39.3%, respectively); however, the mean age difference of unlicensed versus licensed was not significant (16.4 vs 16.5 years). Unlicensed drivers were more likely to identify as black or Hispanic (36% and 30% vs 14% and 16%, respectively) and less likely as white (27% vs 64%). Alcohol use was associated with unlicensed driving, with 51% reporting drinking at least once in the previous month, versus approximately one third of licensed drivers. Lower grades were strongly associated with unlicensed drivers, with only 11% A students, versus 34% of licensed and 16% D to F students, versus 4% of licensed. Unlicensed teens were more likely to attend central city (27%) and rural (45%) schools than licensed teens (11% and 40%, respectively). Unlicensed drivers were less likely to have had a driver's education class (28% vs 62%) and less likely to report a driver's education instructor "most helpful" in teaching driving (4% vs 16%). They were less likely to report fathers as helpful in teaching driving (29% vs 38%) and more likely to report "no one" (23% vs 8%) or male friends (8% vs 2%) as helpful. They also were less likely to report being the usual driver of the vehicle that they drove most often (34% vs 46%).
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Table 2 compares the unlicensed and licensed drivers’ reasons for driving. The 3 most common—"go shopping or do errands," "have fun," and "go out with friends"—did not differ significantly between the 2; however, unlicensed drivers were more likely to drive without a specific aim: 28% reported always "driv[ing] without a place to go," and 21% reported always "driv[ing] to relax," versus 14% and 14% of licensed drivers. They also were less likely "always" to drive specifically "to get to school or work" (22% vs 47%).
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Table 3 shows distributions of driving behaviors and crash outcomes by unlicensed driving status. Unlicensed drivers were much less likely to report seat belt use: 56% "always" used them versus 80% of licensed. Unlicensed teens were considerably more likely to use alcohol or drugs while driving: 20% reported "always" or "sometimes" using alcohol or drugs while driving, versus 9% of licensed drivers. The proportion who reported speeding did not differ significantly between the 2 groups; neither did the rate of recent (previous 12 months) crashes or lifetime injury crashes.
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Table 4 shows the results of a logistic regression that was used to predict unlicensed driving status as a function of demographics likely known from administrative data sources (age, grade in school, gender, race/ethnicity, and average grades). Those with lower grades were more likely to be unlicensed (OR for C versus A students: 2.49 [95% CI: 1.31–4.74]; OR for D versus A students: 5.05 [95% CI: 2.04–12.54]; OR for E/F versus A students: 2.76 [95% CI: 0.86–8.80]). Black teens were more likely to report unlicensed driving than white teens (OR versus white teens: 5.13 [95% CI: 2.64–9.96]), as were Hispanic teens (OR: 2.87 [95% CI: 1.53–5.37]) and other race/ethnicities (OR: 2.28 [95% CI: 1.06–4.90]). Similarly, central city teens were more likely to drive unlicensed than suburban and town district teens (OR: 2.45 [95% CI: 1.22–5.00] and 2.59 [95% CI: 1.08–6.21], respectively). Those who drank at least once a month were nearly twice as likely to drive unlicensed (OR: 1.71 [95% CI: 1.04–2.81]).
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We considered whether independent predictors of unlicensed driving might vary by race/ethnicity by fitting models with interaction terms between race, age, gender, grades, drinking behavior, and urbanicity. Two significant interactions were found. First, unlicensed white teens were marginally less likely to be 10th- and 11th-graders than 9th-graders (OR: 0.41 [95% CI: 0.15–1.12] and 0.24 [95% CI: 0.07–0.84], respectively), whereas Black and Hispanic teens were equally likely to be 9th-, 10th-, or 11th-graders (P = .004 for interaction). Second, the relationship between drinking in the previous month and driving is limited to white teens only (OR: 3.48 [95% CI: 1.18–10.24]); no relationship was found between drinking behavior and unlicensed driving risk among black and Hispanic teens (P = .033 for interaction).
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DISCUSSION |
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TOPABSTRACTMETHODSRESULTSDISCUSSIONCONCLUSIONSREFERENCES |
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This article is the first to describe the prevalence of unlicensed driving in a nationally representative sample of teenagers and factors that are associated with this behavior. We estimate that 4.2% of US 9th- to 11th-graders drive unlicensed at least 1 hour/week without adult supervision. This article also describes the unlicensed teenaged driver population: when compared with licensed drivers, they are more likely to identify as black or Hispanic, live in rural or central city districts, and have lower grades than licensed teens. No difference in unlicensed driving was found in age or gender. Those who reported drinking
1 time per month were more likely to drive unlicensed. No relationship was found between license status and ever being in a crash as a driver; however, unlicensed teenaged drivers were more likely to report engaging in risky behaviors20: less seat belt use, more alcohol/drug use and driving, and more trips without a clear aim. No differences were found in hours of driving per week or speeding.
Our study's unlicensed driving prevalence estimates were lower than those reported in a study by Williams et al15 conducted 20 years ago in select US regions. According to that study, in 1985, 27% of unlicensed teens drove "with friends or others not in family," and 14% drove "by themselves." Our lower prevalence may reflect real decreases in unlicensed driving over time or differences as a result of study methods. The sampling frame in the study by Williams et al was not nationally representative (in contrast to the NYDS), and the surveys’ wording was likely not exactly comparable.
Conversely, the amount of teens who self-reported driving on their own is much higher than 20 years ago and does not differentiate according to licensure status. In the study by Williams et al, only 4% of unlicensed and 44% of licensed teens drove >50 miles/week. In our study, nearly two thirds of teenaged drivers, regardless of license status, drove 3 hours/week. Again, these results may reflect increased exposure to driving or differences in method.
Considering driving behaviors among the unlicensed, our results are comparable to the study by Williams et al regarding drinking and driving but differ regarding purposeful driving and speeding. The study by Williams et al reported 21% driving after drinking; our study found 24%. Conversely, today, 41% drive unlicensed to school; only 3% "usually" did 20 years ago. Moreover, half of the teens in our study admitted speeding (driving >10 mph above the limit); in the study by Williams et al, 19% reported driving >70 mph in the previous month.
Previous research10 primarily conducted with adults found that unlicensed drivers have high crash injury risk after accounting for other crash-related risk factors. According to Fatal Accident Reporting System14 2006 data, nearly 20% of drivers who were aged 14 to 18 and died in fatal crashes did not have a valid license. Our study supports and extends these findings by demonstrating a high prevalence of reported unsafe driving behaviors among the unlicensed; in particular, they reported lower seat belt use rates and increasing injury risk or death when a crash occurs.
Our study did not show increased crash risk among unlicensed teens. This may reflect their age, because teens have very high crash risk as a result of inexperience,1 and study design, a cross-sectional survey of these students versus a crash- or fatal crash–involved population. We did not include information on teens who died in crashes. Demographic characteristics of unlicensed drivers may explain the lack of an observable crash risk difference. Central city teens are the most likely to drive unlicensed, particularly those from minority groups. A recent Milwaukee, Wisconsin,21 study found minority central city teens at increased risk for unlicensed driving largely as a result of license suspension policies designed to prevent unsafe driving practices, particularly alcohol-impaired driving.22 That study, as well as a New Jersey study,23 found that many license suspensions, particularly among minorities, were attributable to economic (unpaid fines) and administrative issues unrelated to driving behavior. A California study24 found lack of citizenship or legal residence documentation as a barrier to teenager licensing. As a result, our study may represent a diverse unlicensed teenaged population: high-risk drivers (those traditionally associated with unlicensed driving) and teens who need to drive but are unable to obtain licensure because of socioeconomic issues.
Our data are concerning regarding who teaches unlicensed adolescents to drive. Teachers can either convey safety messages and safe driving skills or model and teach unsafe practices. Fewer than half of unlicensed drivers attended driver's education. Whereas 16% of licensed drivers endorsed driver's education teachers as their most helpful teacher, far fewer unlicensed drivers (4%) valued them most. Of unlicensed drivers, 23% reported that no one was helpful in teaching them to drive, suggesting that they may have been largely self-taught. Unlicensed drivers were 3 times as likely (7.6% vs 2.4%) to report a male friend as most helpful, raising concern around the likelihood of a friend to promote and model safety. Half of unlicensed drivers (compared with 61% of licensed) named a parent as most valued, suggesting that parents serve key roles in addressing driving safety.
Additional research is needed for better understanding of barriers to licensure and for helping teens successfully participate in the licensing process. Although a license itself does not offer enhanced safety, the licensure process may be protective if it facilitates teenagers and families to adhere to GDL laws and follow a systematic learning-to-drive approach, one that develops skilled, safe drivers by preparing adults to teach and model safe behaviors effectively.
This study has several limitations. Its population included only teens who were in school, so results may not generalize to teens who are not in school. Despite including question categories for school-only licenses, driving with adults, and licenses with other restrictions, some respondents who were classified as unlicensed may have learner permits and answered the licensing status question incorrectly. Furthermore, because this survey is self-report, some teenagers may be more likely to admit unlicensed driving. We also cannot estimate the unlicensed drivers’ total driving exposure because no "licensure date" equivalent exists; neither could we explore participants’ socioeconomic status to validate our hypothesis that unpaid fines cause part of unlicensed teen driving. Finally, in this study, we defined an unlicensed driver as one who drives unlicensed at least 1 hour/week. Future studies might better define an hours or miles driven threshold, marking the transition between infrequent "unlicensed driving" to regular "unlicensed driving," in terms of exposure and associated crash risk.
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CONCLUSIONS |
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TOPABSTRACTMETHODSRESULTSDISCUSSIONCONCLUSIONSREFERENCES |
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A minority (6%) of today's teenaged drivers continue to drive unlicensed. On average, they do not seem to have increased crash risk compared with licensed teens. However, they display increased unsafe driving behaviors, particularly lower rates of seat belt use, which puts them at higher risk for injury and death when a crash occurs. Teenagers’ high incidence of crash injury and death suggests that efforts need to be made to reach this high-risk unlicensed driver population: black or Hispanic teens, teens in rural or central city schools, and teens with low grades.
These teens might be reached through parents, many of whom teach them to drive or lend them their vehicles. In parallel, efforts must help parents to teach and model safe behaviors and good driving effectively. Efforts should also be made to increase driver's education accessibility in communities with higher percentages of unlicensed drivers. This education should be developed to convey state-of-the-art, culturally appropriate safety messages.
Clinicians, particularly those in rural and central city districts, could consider including unlicensed driving in their discussions with adolescents about health risk behaviors. This can be accomplished by emphasizing safety as the final "S" in the adolescent psychosocial assessment strengths, school, home, activities, drugs/substance abuse, emotions/depression, sexuality, and safety (SSHADESS), making driving a core element of the safety screen.25 Furthermore, driving safety discussion can be incorporated into standard practice as part of the preparticipation sports physical for 15- to 18-year-old patients. Once they identify teens at risk, clinicians could emphasize the importance of GDL and address unsafe driving behaviors as outlined by the American Academy of Pediatrics26 to families, guiding them to appropriate resources for helping teens become safe, competent drivers.
Although this study has begun to quantify the problem and impact associated with unlicensed teenaged drivers, additional research is needed for better understanding of barriers to licensing and ways to get all teens into the licensing system. In particular, policies that impose fines for infractions should be reassessed. All teens should be able to learn how to become safe drivers regardless of their ability to pay.
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ACKNOWLEDGMENTS |
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This article was written as part of the Young Driver Research Initiative, a collaborative research program between the Center for Injury Research and Prevention at the Children's Hospital of Philadelphia and State Farm Insurance Companies. State Farm provided financial and research support for the conduct of focus groups that informed the survey.
We thank Dr Dennis Durbin, Danielle Erkoboni, Angela Gafen, J. Felipe Garcia-Espana, Jaime Doyle, and other staff at the Center for Injury Research and Prevention for review and suggestions as well as for project support.
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FOOTNOTES |
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Accepted Jul 23, 2008.
Address correspondence to Flaura K. Winston, MD, PhD, Center for Injury Research and Prevention, Children's Hospital of Philadelphia, 3535 Market St, 11th floor, Philadelphia, PA 19104. E-mail: flaura{at}mail.med.upenn.edu
The authors have indicated they have no financial relationships relevant to this article to disclose.
The opinions expressed in this article are not necessarily those of State Farm Insurance Companies.
| What's Known on This Subject Evidence indicates that unlicensed drivers are at higher risk for crash, injury, and mortality than licensed drivers. The only recent study used a restrictive sample (fatal crashes of drivers <16 years of age involved in police pursuits from 1999 to 2003).
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| What This Study Adds This study fills the gap on the prevalence and description of unlicensed driving in 9th- to 11th-graders in the United States. These data can be used to inform public health, enforcement, and education campaigns that aim to reduce illegal driving.
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PEDIATRICS (ISSN 1098-4275). ©2008 by the American Academy of Pediatrics
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