Characterizing the Learning-to-Drive Period for Teens with Attention Deficits

Abstract

Objective:

Motor vehicle collisions are the leading cause of death among teenagers, accounting for approximately 1 in 3 deaths for this age group. A number of factors increase crash risk for teen drivers, including vulnerability to distraction, poor judgment, propensity to engage in risky driving behaviors and inexperience. These factors may be of particular concern and exacerbated among teens learning to drive with attention deficits. To our knowledge, our study is among the first to systematically investigate the experiences of novice adolescent drivers with attention deficits during the learner period of a Graduated Drivers Licensing program.

Method:

Survey and on-road driving assessment (ODA) data were used to examine parent and teen confidence in the teens’ driving ability, driving practice frequency, diversity of driving practice environments, and driving errors among teens with attention deficits as defined by ADHD diagnosis or parent-reported trouble staying focused.

Results:

When teens’ driving skill was evaluated at the conclusion of the learner period, teens with ADHD exhibited more driving errors than their typically developing counterparts (p=.034). Teens trouble staying focused were more likely to have their ODA terminated (p=.019), marginally lower overall driving scores (p=.098), and exhibited more critical driving errors (p<.01) compared to typically developing teens.

Conclusions:

These findings may have implications on the learning-to-drive period for adolescents with attention deficits. Adjustments may need to be made to the learner period for teens with attention deficits to account for attention impairments and to better instill safe driving behavior.

Motor vehicle collisions (MVCs) are the leading cause of death among teenagers, accounting for approximately 1 in 3 deaths for this age group [1]. A number of factors increase crash risk for teen drivers, including vulnerability to distraction [2, 3], poor judgment, propensity to engage in risky driving behaviors, [4–9] and inexperience [10, 11]. These factors may be of particular concern and exacerbated among teens learning to drive with trouble staying focused, including those teens with Attention-Deficit/Hyperactivity Disorder (ADHD). Although commonly diagnosed in childhood, ADHD symptoms often persist into adolescence – a period when teens are becoming independent and tasks such as driving are critical for successful transition into adulthood [12].

ADHD and Driving

ADHD, a neurodevelopmental disorder characterized by impairments in attention and hyperactive behavior, is one of the most common developmental disabilities in the U.S. affecting 8–10% of the population [13]. Adolescents with ADHD are at increased risk for a MVC than typically developing peers, with recent estimates indicating that adolescents diagnosed with ADHD have a 36% higher risk of MVC [14]. These risks are especially elevated just after licensure. Although the precise mechanisms are not well understood, available research has revealed decrements in overall driving performance (e.g., lane maintenance errors, greater speed fluctuation) [15] and increased engagement in risk-taking behavior (e.g., seat belt nonuse, speeding, distracted driving, alcohol/drug use) among adolescent drivers with ADHD [16].

Previous research has implicated the characteristic deficits in executive function, inattention and hyperactivity seen in ADHD as potential mechanisms behind these risky behaviors and decrements in driving performance. Both self-report and naturalistic study findings suggest that young adult drivers with ADHD have significantly poorer driving outcomes compared to their typically developing counterparts [17–19]. These outcomes include: receiving fines or remedial driving class [17], involvement in MVCs, sudden breaking or acceleration events, illegal vehicle maneuvers, and distracted driving behaviors (i.e., removing hands from the wheel to reach for a moving object in the car) [18]. Specifically, inattentive symptoms may play a significant role in contributing to poorer self-reported driving outcomes [20]. Adolescents with ADHD are more likely to have their license suspended, have higher incidences of traffic and speed violations, have difficulty with lane maintenance [21], and, a higher likelihood of at-fault crashes [22]. Despite these demonstrated driving risks, drivers with ADHD also display a positive illusory bias in regards to their driving abilities [23–25]. This overestimation of ability may put drivers with ADHD at increased risk in driving environments that may introduce additional danger such as driving at night, driving in bad weather, or driving while distracted [23].

Overall, research suggests that drivers with ADHD exhibit significantly poorer driving outcomes, higher MVC risk and increased risky driving behavior compared to typically developing drivers. However, the majority of existing research on drivers with ADHD consists of drivers that are already licensed. Little is known about the experiences of novice adolescent drivers with attention problems, including ADHD, during the learner period of Graduated Drivers Licensing (GDL) while they are still under supervision of a qualified adult.

The Learner Period of GDL

Research suggests that both parental engagement and challenging, diverse practice during the learning to drive period are crucial for developing safe driving behaviors [4, 26–28]. However, for many families practice drives tend to be opportunistic drives of convenience with parents generally focusing on basic vehicle maneuvering, maxims, and rudimentary knowledge, and not on higher-order facets of driving (e.g., hazard anticipation) [29–31]. The emotional climate in the practice vehicle may affect parents’ abilities to supervise as prior research has found that parents in mutually supportive dyads had stronger intentions to be engaged practice supervisors compared to dyads where both members reported receiving low support; interestingly, no benefit was observed for only having one member of the dyad provide support [32].

A lack of an engaged driving practice supervisor may be more prevalent among parents of teens learning to drive with ADHD. A suboptimal relational climate among parents and children with ADHD have been well documented in previous literature and the high-pressure situations that can arise in the learning to driver period may increase the strain on these parent-teen relationships [33]. Parents of adolescents with ADHD report higher levels of stress [34], poorer family function [35] and lower self-efficacy in parenting skill [36]. Further, the aggressive driving behavior and ease of frustration with other drivers previously noted in both adolescent and adult drivers with ADHD [37, 38] may be a barrier to parental driving instruction. Collectively, these factors could negatively affect the quality of pre-license practice driving. To our knowledge, the current study is among the first to systematically investigate the experiences of novice adolescent drivers with attention deficits during the learner period of Graduated Drivers Licensing.

The Current Study

To address these gaps in the literature, we conducted a secondary analysis of existing data from a randomized controlled trial on parental engagement and learning to drive (NCT01498575)[39]. We compared teen drivers whose parents reported they either were diagnosed with ADHD or had trouble staying focused (TSF) and typically developing (TD) teen drivers on their self-reported behaviors and cognitions related to practice driving and their performance on the on-road driving assessment. Teens with TSF were included to capture teens who may have subclinical levels of inattention and hyperactivity or may have clinical levels of inattention and/or hyperactivity without an ADHD diagnosis. As such, this study is among the first to attempt to explore the learning-to-drive period in teen drivers with and without ADHD or TSF. We hypothesized that compared to TD teens, teens with ADHD and teens with TSF would exhibit more driving errors. The literature is mixed with respect to whether or not we should expect teens with ADHD and TSF to practice more or less than TD teens. Therefore, we made no a priori hypothesis about driving practice diversity differences between teens with ADHD, teens with TSF and teens that are TD. However, we expected that parents and teens with ADHD and TSF would find their practice time together as more stressful, which could cause them to practice less often and in less challenging situations than parents of TD teens.

Method

Briefly, parent-teen dyads were randomized 3:2 to a web-based parent Teen Driving Plan (TDP) intervention condition or a usual practice control condition for 24 weeks during the learner’s-permit period. The overall goal of the TDP was to improve the quality and quantity of practice driving using (1) a practice tutorial library consisting of short animated videos on how to practice specific environment-based goals (e.g., lane management on highways) and how to create a positive learning environment; (2) an interactive practice planner that families could use to plan drives ahead of time (e.g., pick a date and time, practice activity); and (3) a logging and rating tool [39]. 512 parent-adolescent dyads participated in the original trial. Parent-adolescent dyads from both the TDP and usual practice conditions were then quasi-randomly assigned to receive the ODA or to a survey-only arm. Parents and teens completed surveys every 6 weeks for 24 weeks and teens assigned to the ODA assessment completed it at 12 and 24 weeks — the late, or 24-week, ODA is used for the current analysis. See published work from the larger clinical trial for more detailed study design [39]. Only participants who completed the 24-week ODA and had complete data for the periodic surveys over the 24 weeks were included in the current analyses.

Enrollment/Baseline Survey.

At enrollment, parents of teens were asked, “Has a health care professional ever diagnosed or treated your teen for Attention Deficit Hyperactivity Disorder (ADHD)?” and “In your opinion, does your teen have trouble staying focused (TSF)?”. Responses to these items were used to classify teens into the ADHD and TSF groups. Categories were mutually exclusive, such that if a teen was categorized as having ADHD and TSF they were categorized into the ADHD group. Teens were also asked to complete four questions assessing sensation seeking from the Brief Sensation Seeking Scale for children (BSSS) to further assess ADHD characteristics [40]: 1) I like to do frightening things; 2) I like to explore strange places; 3) I like new and exciting experiences even if I have to break the rules; 4) I prefer friends who are exciting and unpredictable. Each of these questions was rated on a scale of 1 (Strongly disagree) to 5 (Strongly agree). The responses to these four questions were averaged to calculate an overall sensation seeking score. Demographic characteristics (e.g., age at enrollment, race) were also collected at enrollment.

Periodic Surveys.

At 6-week intervals over the course of the 24-week study, parents and teens completed web surveys electronically to collect information about the frequency of practice drives, where driving practice occurred, and their driving confidence.

Driving Practice Diversity.

Parents and teens reported the types of driving environments they practiced in during the 24 weeks. Driving environments included: an empty parking lot, residential neighborhoods, intermediate (one/two lane) roads, commercial roads (i.e., around shops and businesses), highways, country roads, at night and in bad weather. Driving practice diversity was determined by summing the number of environments the dyad practiced at least 1–2 hours in.

Driving Confidence.

Teens were also asked a question related to how they view themselves as drivers in relation to other teen drivers comparable in driving experience: “Compared to other teens with as much driving experience, I would rate my skills as…” (1 Much below average to 5 Much above average). Parents were also asked this question in regards to their teen’s driving abilities.

On-road Driving Assessment.

An on-road driving assessment (ODA) was administered at 12 and 24-weeks after enrollment by a certified driver rehabilitation specialist (CDRS) to those adolescents assigned to the ODA arm of the original trial [41]. CDRSs were unaware of participants’ ADHD status at the time of assessment, unless the participant or their parent disclosed this information verbally to the CDRS. Several categories of driver performance were measured: terminations, errors, critical errors, and an overall subjective driving score [27]. These attributes were assessed on both the 12-week and 24-week ODAs. The late ODA was used for the current analysis as it is more comprehensive than the 12-week assessment and it is of greater interest to know how teens with ADHD might differ from typically developing teens just prior to licensure. The late route was 30.6 km in length (approximately 19.0 mi) and consisted of driving in a parking lot, residential neighborhood, intermediate roads, a complex commercial district, and rural and highway road segments with speed limits ranging from 40 to 88 km/h (approximately 25 to 55 mph). For more detail on the ODA please see Mirman et al., 2014.

Terminations.

The ODA was terminated (i.e., deemed a “fail”) if: (1) driver action or inaction required the CDRS to intervene to prevent a collision; (2) driver required assistance from the evaluator to complete the task safely; (3) driver violated traffic law; (4) evasive action was required by another driver or pedestrian to avoid a collision; or (5) the evaluator determined that the teen could no longer continue the assessment safely for another reason that was not pre-specified.

Errors.

The ODA was also used to assess errors across 7 categories including: basic control items, cognitive items, low-demand items, high-demand items, left-turn items, right-turn items and straight at intersection items. During the ODA, the CDRS recorded the number of errors the teen made in each of these task categories.

Critical Errors.

Critical Errors (CEs) occurred when the teen did one of the following: strikes object or goes over curb, disobeys traffic signal, performs a dangerous maneuver, speeds, improperly uses auxiliary equipment, lane violation, or disobeys safety personnel/emergency vehicle.

Overall Score.

The CDRS provided an overall driver rating score from 1 (Poor) to 10 (Excellent) at the conclusion of the assessment.

Analysis Plan.

All analyses were conducted using SPSS Statistics version 24 [42]. Distributions, means and standard deviations of all variables were examined. One-way analyses of variances (ANOVAs) were used to compare differences among the groups for all continuous and ordinal variables while Pearson χ²and Fishers exact tests were conducted for categorical variables. P-values less than .05 were considered significant for all analyses. There was no a-priori hypothesis that the TDP would be differentially effective for teens based on ADHD status and the study was not powered to detect for effect modification of TDP by ADHD status; therefore, we did not include TDP assignment status in our analyses of the survey data.

Results

One hundred and thirty-four teenagers completed the late ODA and had complete survey data (134 dyads). Of these 134 adolescents, 113 (84.3%) were typically developing, 12 (9.0%) had ADHD, and 9 (6.7%) had TSF. Participants in the ADHD group were marginally more likely to be male than typically developing participants (p= .072). As ADHD is more common in males than females, it was expected that a higher percentage of the teens in the ADHD group would be male [13]. There were no significant group differences in age or behind-the-wheel driving practice at study enrollment (average behind-the-wheel practice prior to enrollment was 1.84 hours). Teens with ADHD, teens with TSF and TD teens did not significantly differ on any other socio-demographic variables (Table 1).

Table 1.

Sociodemographic Characteristics

	ODA Sample (n= 134)
	TD (n=113)		ADHD (n=12)		TSF (n=9)
Variables	M (SD)	n (%)	M (SD)	n (%)	M (SD)	n (%)
Teen
Age (Years)	16.08 (0.27)	-	16.17 (0.39)	-	16.11 (0.33)	-
Gender (Male)	-	47 (41.6%)	-	9 (75.0%)	-	5 (55.6%)
Ethnicity (Non-Hispanic)	-	109 (96.5)	-	12 (100%)	-	9 (100%)
Sensation Seeking	2.53 (0.75)	-	2.73 (0.58)	-	2.83 (0.80)	-
Pre-Enrollment Driving Practice	1.88 (1.59)	-	1.29 (1.19)	-	2.00 (1.03)	-
Parent
Gender (Male)	-	33 (29.2%)	-	1 (8.3%)	-	2 (22.2%)
Ethnicity (Non-Hispanic)	-	110 (97.3%)	-	12 (100%)	-	9 (100%)
Education
Some college or less	-	25 (22.1%)	-	3 (25.0%)	-	4 (44.4%)
College graduate	-	52 (46.0%)	-	3 (25.0%)	-	2 (22.2%)
Graduate degree	-	35 (31.0 %)	-	6 (50.0%)	-	3 (33.3%)
Parent Marital Status (Married)	-	104 (92.0%)	-	12 (100%)	-	7 (77.8%)

Note: M= Mean, SD= Standard Deviation. Bold= p < .05.

Descriptive statistics for self-report questionnaire data can be found in Table 2. No significant differences emerged between the groups for parent or teen ratings of confidence in driving, number of driving environments practiced in, or the number of hours practiced in each environment.

Table 2.

Differences in Supervised Practice, Parent-Adolescent Relationship, and Perceptions of Confidence by group

	Total	TD	ADHD	TSF	p
Variables	M (SD)	M (SD)	M (SD)	M (SD)
	n=98	n=82	n=9	n=7
Hours of driving practice (Average)	10.99 (5.58)	10.94 (5.52)	12.59 (6.81)	9.57 (4.89)	.551
	n=133	n= 113	n= 11	n= 9
Practice diversity (# of environments)	6.74 (1.40)	6.73 (1.46)	7.27 (0.65)	6.33 (1.27)	.310
	n=125	n= 107	n= 10	n= 8
Practice by Environment
Parking lot	3.28 (1.08)	3.29 (1.12)	3.40 (0.84)	3.00 (0.93)	.720
Neighborhood	4.26 (1.27)	4.23 (1.26)	4.50 (1.34)	4.38 (1.30)	.793
Intermediate roads	5.15 (1.03)	5.10 (1.06)	5.70 (0.68)	5.13 (0.99)	.217
Commercial zones	4.39 (1.30)	4.40 (1.30)	4.90 (1.10)	3.63 (1.30)	.115
Highway	4.10 (1.52)	4.11 (1.50)	4.40 (1.51)	3.50 (1.77)	.441
Rural roads	3.48 (1.68)	3.47 (1.66)	4.20 (1.69)	2.75 (1.91	.189
At night	4.04 (1.33)	3.96 (1.29)	4.90 (1.19)	4.00 (1.69	.102
In bad weather	3.43 (1.24)	3.45 (1.22)	3.30 (1.16)	3.38 (1.69)	.929
	n= 125	n= 107	n= 10	n= 8
Teen driving confidence	3.58 (0.73)	3.55 (0.72)	4.00 (0.82)	3.50 (0.76)	.484
	n= 131	n= 111	n= 11	n= 9
Parent driving confidence (n=131)	3.56 (0.73)	3.56 (0.70)	3.73 (1.01)	3.33 (0.71)	.170

Note: M= Mean, SD= Standard Deviation. Bold= p < .05; Study variables were not normally distributed, however Mann-Whitney, non-parametric analyses revealed no differences in significance findings.

Descriptive statistics and p-values for all late ODA assessment variables can be found in Table 3. Teens with TSF were more likely to have their ODA terminated compared to teens with ADHD or TD teens (p= .019, Fisher’s exact test); 3 out of 9 (33%) of teens with TSF had their drives terminated compared to 9 of 104 (8%) TD teens and 0 of 12 (0%) teens with ADHD. Further, teens with TSF received marginally lower overall driving scores (M= 3.78, SD= 2.58) compared to TD teens (M= 5.39, SD= 2.06; p= .09). Teens with ADHD however, made significantly more total errors (M= 18.83, SD= 6.37) than TD teens (M= 14.49, SD= 6.07; p= .03). When specific task categories were examined, teens with ADHD made significantly more errors during high-demand tasks (F(2,132)= 3.41, p= .04), and right turn tasks (F(2,132)= 4.21, p= .03) compared to TD teens. Also compared with TD teens, teens with TSF exhibited significantly more errors during straight at intersection tasks (F(2,132)= 3.09, p= .049).

Table 3.

Differences in driver performance by ADHD and TSF status

	Late ODA
	TD (n=113)	ADHD (n=21)	TSF (n=9)
Variables	M (SD)	M (SD)	M (SD)	p
Overall driver rating	5.39 (2.06)*	5.25 (2.45)	3.78 (2.59)*	.098*
Total errors	14.49 (6.07)	18.83 (6.37)	17.89 (9.35)	.034
Error Categories
Basic control	4.90 (1.97)	5.50 (1.09)	6.11 (1.76)	.130
Cognitive	1.02 (0.91)	1.08 (0.90)	1.44 (1.01)	.401
Low-demand	2.60 (2.10)	3.58 (2.02)	3.11 (4.59)	.335
High-demand	1.88 (1.63)	3.08 (1.98)	2.67 (2.12)	.036
Center turn	2.40 (1.91)	2.75 (2.22)	3.11 (2.57)	.518
Right turn	1.58 (1.31)	2.58 (1.51)	1.00 (1.32)	.017
Straight at intersection	0.12 (0.34)	0.25 (0.62)	.44 (0.73)	.049
Critical Errors
Overall CE	1.09 (1.49)	1.75 (2.09)	2.78 (2.77)	.009
Auxiliary use	0.01 (0.09)	0.08 (0.29)	0	.122
Dangerous maneuver	0.49 (0.85)	0.67 (1.23)	0.78 (0.83)	.536
Lane violation	0.04 (0.21)	0.25 (0.45)	0.67 (1.11)	< .001
Disobeys safety vehicles	0	0	0	-
Disobeys traffic signals	0.21 (0.47)	0.33 (0.49)	0.78 (1.09)	.010
Speeding	0.24 (0.57)	0.33 (0.88)	0.22 (0.44)	.867
Strikes object/curb	0.11 (0.31)	0.08 (0.29)	0.33 (0.71)	.158

Note: M= Mean, SD= Standard Deviation, Bold= p < .05

^*= p < .10.

Study variables were not normally distributed, however Mann-Whitney, non-parametric analyses revealed no differences in significance findings.

Teens with TSF also committed more CEs overall (M= 2.78, SD= 2.77) compared to TD teens (M= 1.09, SD= 1.49; F(2,132)= 4.84, p= .009). Of the CEs committed by teens with ADHD: 38% were dangerous maneuvers, 19% were for disobeying traffic signs, 14% were lane violations, 19% were for speeding, 5% were for striking an object or curb and 5% were auxiliary use errors. For teens with TSF: 28% of CEs were dangerous maneuvers, 28% of CEs were for disobeying traffic signs, 24% of CEs were lane violations, 8% of CEs were for speeding and 12% of CEs were for striking an object or curb. Of the CEs noted in the TD teens: 45% were dangerous maneuvers, 22% were for speeding, 19% were for disobeying traffic signs, 10% were for striking and object or curb, 3% were lane violations, and 1% were auxiliary use errors. None of the teens committed any CEs for disobeying safety vehicles. Critical error sub-type analyses indicate teens with TSF made significantly more lane violations (M= 0.67, SD= 1.11) than both TD teens (M= 0.04, SD= 0.21; p < .001) and teens with ADHD (M= 0.25, SD= 0.45; p= .026), and were more likely to make errors disobeying traffic signals (M= 0.78, SD= 1.09) than TD teens (M= 0.21, SD= 0.47; p = .007) (Table 3).

Discussion

The overall goal of this study was to characterize the learning to drive process among teens with ADHD and teens with TSF compared to typically developing teens. Previous research has focused mainly on adolescents and adults with ADHD who are already licensed to drive independently and rarely include teens who have trouble staying focused. This study addresses a gap in the literature by examining driving practice frequency, diversity of driving practice environments and driving errors among teens with ADHD and TSF who are still learning to drive using questionnaires and on-road assessment data. When teens’ driving skill was evaluated by a CDRS at the conclusion of the learner period, teens with TSF were rated as poorer drivers and were more likely to have their drive terminated and teens with ADHD exhibited more driving errors than their typically developing counterparts, a finding consistent with previous work on adolescents and adults with ADHD who have already obtained a driver’s license. This increase in errors and poor overall driving rating are interesting in light of the similarity in practice amount, driving practice diversity and driving confidence ratings of teens with ADHD, teens with TSF and typically developing teens. These findings may have implications on the learning-to-drive period for adolescents with ADHD and teens with TSF.

Learning to Drive Experience

Based on findings of survey response questions assessing parent and teen confidence in the teens’ driving ability, driving practice diversity, and the variety of practice environments, teens with ADHD, TSF and TD teens were largely similar in their learning to drive experiences. Both groups reported high levels of driving practice diversity and good variety in the time they were spending in various driving environments. Contrary to previous literature and previous findings of parents and teens with other developmental disabilities such as autism [43] there were no notable differences in driving confidence for teens with ADHD or TSF compared to TD teens. In combination with the findings of the ODA demonstrating significant differences in the driving performance of teens with ADHD, teens with TSF and typically developing teens, the lack of difference in driving confidence suggests the possibility of positive illusory bias commonly seen in ADHD populations in relation to driving performance [23, 24].

On-road Driving Assessment

Teens with ADHD and teens with TSF committed more overall errors, errors in high-demand tasks, going straight through intersections, and disobeying traffic signals than TD teens. Teens with TSF were also given significantly poorer overall driving ratings compared to typically developing teens. These findings indicate that targeted practice and training during the learning to drive period may be needed for teens and adolescents with ADHD and other attention impairments. Previous driving simulator research has implicated inattention as a source of safety risk in this population [19], so training dedicated to ameliorating these weaknesses may prove beneficial toward improving driving performance and reducing errors. Research in the area of attention and driving is increasing due to the rise in rates of distracted driving among the general population over the last decade [44]. Little research however has focused on the benefits of general attention training to driving performance in teens with attention impairments. General attention training tasks have shown some initial promise in transferring to real-world tasks, such as driving. In older populations of drivers, simple computer-based, attention training programs have yielded significant improvements in simulated driving performance [45]. More specifically, improvements were seen in participants’ lane position errors, an area highlighted by the current study as a significant source of errors among teens with ADHD and teens with TSF. However, computerized interventions to improve aspects of executive function such as working memory and impulse control in individuals with attention impairments are few and have yielded inconsistent results as to the effectiveness and transfer of these training programs [46]. The significance of research on effective interventions is highlighted by the current study’s findings that despite the similarities in the learning to drive process, teens with attention impairments displayed more errors and poorer overall driving performance compared to their typically developing counterparts. More research is needed to identify feasible, effective interventions to improve attention and further, driving risk in teens with ADHD and attention impairments.

Limitations

The main limitation to this study is the possibility of sample selection bias. Parents who chose to participate in the study may be more engaged or concerned about their adolescents’ driving safety than parents who chose not to participate in the study. It should also be noted that due to the nature of the disorder, teens in the ADHD group tended to be male [13]. This disproportionate percentage of males in this group may have contributed the differences in driving errors [47]. Future studies should target females with ADHD still learning to drive to identify the unique contributions of gender and group status to the learning to drive period. In addition, the original purpose of the trial was not to compare teens with ADHD or trouble staying focused to typically developing teens. Given this, ADHD diagnosis was not confirmed by physicians or assessed using gold-standard, diagnostic measures. Teens whose parents reported that their teen had trouble staying focused were also included in the study as a separate group. Although it is possible that the teens whose parents reported that they had trouble staying focused were exhibiting subclinical levels of ADHD, it is also possible that these teens were exhibiting attention deficits related to some other condition or diagnosis such as depression, anxiety, or some other condition [48, 49]. Nevertheless, these teens did exhibit elevations in driving errors and had poorer overall driving ratings compared to typically developing teens. This may suggest that attention deficits in general—and not those that meet the clinical definition of ADHD—may affect driving performance. Future studies should aim to recruit a larger sample of teen drivers with a confirmed diagnosis of ADHD, information about the medications that these teens are taking, and obtain more extensive and detailed medical histories for teens who experience trouble staying focused. Further, various ADHD subtypes (e.g., predominately inattentive, predominately hyperactive and combined type) and teens with common comorbidities (e.g. anxiety, depression, oppositional defiant disorder) should be included to examine the differences within the ADHD group in the learning to drive process. Because the original trial was not designed to examine the impact of ADHD and attention deficits on the learning-to-drive process, the sample sizes of the ADHD and TSF groups were small. The current study’s findings highlight the need for larger, more in-depth investigation into the learning-to-drive process of these vulnerable road users. Nevertheless, this is currently the largest systematic on-road study of learner teens with ADHD and teens who might have symptoms related to trouble staying focused.

Future Research

Future research should further investigate the impact of structured driver training programs on families of teens with attention deficits. These driving training plans should be tailored to meet the needs of this specific population of teen drivers and may benefit from extending the learning to drive period typically prescribed to typically developing teens. Future studies should also recruit a larger and more diverse group of teens with attention deficits to examine a broader range of teens with ADHD including teens with various ADHD subtypes as well as teens with elevated but subclinical levels of inattention and hyperactivity. ADHD is largely heterogeneous in nature so recruiting a larger sample of individuals with ADHD will allow researchers to capture the variability in ADHD presentation. Although it was not collected in the current study, parental ADHD diagnosis/symptomology may also provide a more complete picture of the complex parent-teen relational component of the learning to drive period of teens with attention deficits.

Figure 1.

Enrollment diagram for the original trial.