Transportation Research Part F 14 (2011) 447–455

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Transportation Research Part F

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Minimising risks and distractions for young drivers and theirpassengers: An evaluation of a novel driver–passenger training program

Michael G. Lenné a,⇑, Charles C. Liu a, Paul M. Salmon a, Marnie Holden b, Simon Moss b

a Accident Research Centre, Monash University, Australiab School of Psychology & Psychiatry, Monash University, Australia

a r t i c l e i n f o

Article history:Received 30 October 2010Received in revised form 16 July 2011Accepted 1 August 2011

Keywords:Young driversPassengersCommunication

1369-8478/$ - see front matter � 2011 Elsevier Ltddoi:10.1016/j.trf.2011.08.001

⇑ Corresponding author. Address: Accident Researfax: +61 3 9905 4363.

E-mail address: Michael.Lenne@monash.edu (M.

a b s t r a c t

The purpose of the present study was to evaluate a pilot program designed to teach com-munication skills to young drivers and passengers. Sixty-two young males recruited as 31pairs of friends, all aged between 18 and 21 years and holding a probationary driverslicence, were randomly assigned to a training or no-training condition. A training programwas developed based upon elements of existing team training programs. Driver and pas-senger pairs operated a driving simulator through scenarios designed to measure aspectsof safe driving behaviour and hazard response. Communications between driver and pas-senger were also measured. All participants were administered the Driver Behaviour Ques-tionnaire before and approximately 2 months after simulator testing. Compared to theuntrained group the trained participants exhibited a larger following distance, reducedspeed significantly when faced with an unexpected hazard on the road, and exhibited moresafe communications. Although current passenger restrictions are warranted, the presentresults reveal an alternative view of adolescent passengers: rather than being a negativeinfluence on drivers, adolescent passengers can potentially be trained to become a positiveinfluence.

� 2011 Elsevier Ltd. All rights reserved.

1. Introduction

Young drivers are over-represented in road crash statistics, and road crashes are the major cause of death for peopleaged 15–24 in OECD countries (Organisation for Economic Co-operation and Development, 2006). One important risk fac-tor for young drivers is the presence of passengers, although evidence indicates that the presence of certain types of pas-sengers, in particular, older passengers and female passengers, enhances driving behaviour (Engstrom, Gregersen,Granstrom, & Nyberg, 2008; Geyer & Ragland, 2005; Rice, Peek-Asa, & Kraus, 2003; Vollrath, Meilinger, & Kruger,2002). There is considerable evidence however that young drivers are more likely to crash when passengers are present(e.g., Chen, Baker, Braver, & Li, 2000; Doherty, Andrey, & MacGregor, 1998; Geyer & Ragland, 2005; Preusser, Ferguson, &Williams, 1998). For drivers under 25 years in Australia, carrying two or more peer age passengers is associated with anincreased risk of crash, whereas no such association is observed for drivers who were 25 years and older (Lam, Norton,Woodward, Connor, & Ameratunga, 2003).

. All rights reserved.

ch Centre, Monash University, Clayton campus, Building 70, VIC 3800, Australia. Tel.: +61 3 9905 4669;

G. Lenné).

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1.1. Passenger influences on young drivers

In the literature noted above the influence of young passengers in distracting young drivers is often acknowledged. Po-tential distractions may be visual (when drivers shift their eyes from the road to passengers), auditory (when passengersadjust the radio), or cognitive (when drivers and passengers converse). Compounding this vulnerability to distractions arethe findings that, compared to experienced drivers, young drivers utilise less efficient hazard detection strategies and pro-cessing abilities, exhibit an impaired capacity to attend to passengers and other distractions, as well as demonstrated limitedawareness of when to moderate passenger interaction in line with the demands and context of the driving situation(Crundall, Bains, Chapman, & Underwood, 2005; Deery, 1999; Underwood, 2007).

Another major factor contributing to the negative effect of passenger carriage on young drivers is risk taking behaviour(Williams, Ferguson, & McCartt, 2007). Young drivers, particularly male drivers, have been observed to take greater drivingrisks, such as speeding and close following, when accompanied by young male passengers; in contrast, the presence of fe-male and adult passengers has been observed to curb the risky behaviour of young drivers (McKenna, Waylen, & Burkes,1998; Simons-Morton, Lerner, & Singer, 2005). Risk taking behaviour has also been linked to higher offence and accidentrates in young male drivers compared to their female counterparts (Laapotti, Keskinen, Hatakka, & Katila, 2001). Young maledrivers report engaging in riskier behaviour when driving with young male passengers compared to females or adults (Regan& Mitsopoulos, 2001; Ulleberg, 2004; Williams et al., 2007), and young male passengers report that they may explicitlyencourage risk taking in their male friends (Regan & Mitsopoulos, 2001).

1.2. Managing the risks associated with passengers

Several approaches to the management of these passenger risks are discussed in the literature (see Williams et al. (2007)for a review). Many countries, including the US, New Zealand, and Australia, have introduced legal restrictions on the num-ber and age of passengers that a young driver is allowed to carry. In the state of Victoria in Australia, for example, driverswho are within 1 year of having obtained their probationary licence will be permitted to carry, at most, one passenger aged16–21 years (Arrive Alive Action Plan, 2008).

Such restrictions can be complemented with education and training programs. For example, passenger and peer influ-ences were targeted in a traffic safety campaign in Norway, intended to generate positive traffic safety attitudes and aware-ness of risky driving practices. The campaign included a specific strategy termed ‘Speak Out!’ designed to empower youngpassengers to declare unsafe driving and to refuse lifts with unsafe drivers. This educational component of the campaignwas accompanied by an increase in police enforcement, which targeted speeding and drunk driving in young drivers. Elvik(2000) found evidence of a reduction in passenger injuries; however, because the campaign consisted of both education andpolice enforcement, the resulting improvements in safety cannot be attributed to education alone.

More recently in the US, a 10-week training program, involving interactive lessons, small-group discussions, and roleplays, entitled ‘You Hold the Keys’, was implemented among teens in high school to increase safe driver and passengerbehaviours (King, Vidourek, Love, Wegley, & Alles-White, 2008). One of the unique features of the program was the studentexposure to the experiences of crash victims who had been victimised by unsafe drivers. In the immediate follow-up, stu-dents reported being more likely to engage in safe behaviours, such as wearing seatbelts, and were more likely to avoid drinkdriving and travelling with another drunk driver. Many of the reported improvements were maintained even 6 months afterthe first evaluation (King et al., 2008).

This study extends existing research by providing a training program to promote safe behaviours between driver–passengerpairs, thereby providing a means to support moderation of behaviour, and by assessing the impact of this initiative throughboth self-reported behaviours and behavioural observation in a driving simulator. The content of the program encompassedelements of previous programs that encouraged teenage passengers to voice their disagreements with drivers when they weredriving dangerously (Elvik, 2000; King et al., 2008). Young male drivers and passengers were chosen given that previous re-search confirms the negative influence of young male passengers on young drivers, the reluctance of young males to informthe driver when they feel unsafe (Ulleberg, 2004), and higher crash risk. It was hypothesised that the training program, deliv-ered to young male pairs, would improve driver–passenger communications, reduce risky driving (car following and speed),and would enhance hazard detection and response.

2. Method

2.1. Participants

Participants were 62 young males, recruited as 31 pairs of friends, aged between 18 and 21 years and holding a proba-tionary drivers licence. Participant pairs were randomly assigned to one of two conditions: a training condition or controlgroup. Sample demographics are presented in Table 1, with the two groups differing on the time reported driving per week(p < 0.05). The study was approved by the Monash University Human Ethics Committee.

Table 1Sample demographics (Means with SDs in parentheses).

Variable Experimental condition

Training Control

Age (years) 19.69 (1.02) 19.49 (0.86)Time holding probationary licence (months) 14.44 (10.56) 13.05 (9.63)Time driving per week (h) 12.11 (11.52) 6.40 (4.12)% of time driving while a friend is a passenger 40.84 (29.38) 43.99 (28.73)Time as passenger per week (h) 3.22 (6.31) 1.74 (2.02)

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2.2. Materials and equipment

2.2.1. Driver Behaviour QuestionnaireSelf-report of real-world driving behaviour was assessed using a modified version of the Driver Behaviour Questionnaire

(DBQ; Aberg & Rimmo, 1998). The questionnaire comprised 24 items: eight relating to violations (e.g., ‘‘Deliberately exceedspeed limit on main roads during low traffic’’), eight relating to mistakes (e.g., ‘‘Underestimate the speed of an oncomingvehicle when overtaking’’) and eight relating to lapses (e.g., ‘‘Fail to notice when a traffic-signal turns green’’). Participantswere asked to reveal how often they experienced the described situation by responding on a 6-point scale. Each participantcompleted the DBQ on two occasions: pre-treatment before the simulator test session and again approximately 5–6 weekslater.

2.2.2. Driving simulatorDriving behaviour was measured in a driving simulator. The simulator consisted of a Holden sedan with normal interior

features. A curved projection screen located in front of the vehicle provided a field of view subtending angles of approxi-mately 180� horizontally and 40� vertically from the driver’s viewpoint. The rear screen provided a field of view subtendingangles of approximately 60� horizontally and 40� vertically. A quadraphonic sound system provided realistic traffic sounds.The system simulated Doppler shift and atmospheric damping effects. Simulations were designed and run using a SiliconGraphics Indy (primarily for developing, running, and replaying simulation scenarios); a Silicon Graphics Onyx (primarilyfor graphics generation, handling vehicle data inputs and outputs, controlling the audio system and vehicle dynamics,and road database development); and a personal computer (for generating sounds). The car was mounted on a motion plat-form, which produced realistic road feel and vehicle dynamics and had three actuators: The front two actuators were placedunder the front axle, and the rear actuator was placed in the centre of the rear axle, to generate up and down movements andpitch and roll rotations. The experimenter controlled driving simulations from a control room located next to the simulationroom. The control room contained a device that allowed two-way communication between the experimenter and the par-ticipants as well as a video monitor for visual monitoring of the participant.

2.3. Procedure

Participant pairs were randomly allocated to a training (n = 32) or no training (control) condition (n = 30). Participantpairs in both conditions completed a short driving task at the MUARC simulation facility. Participants in the trained groupcompleted a facilitated training session 1–2 weeks prior to the undertaking this driving task (detailed in the following sec-tion). Participants in both conditions completed the DBQ twice. The pre-testing DBQ was administered prior to the trainingsession for the trained group, and prior to the driving simulator task for the control group. For both groups the post-testingDBQ was issued 5–6 weeks after the simulator drive.

Upon arrival for the driving task one of the participants was randomly chosen (by a coin toss) to be the ‘‘driver’’ and theother as the ‘‘passenger’’. Before entering the simulator, all participants completed a demographics questionnaire. Driverscompleted a practice scenario to familiarise themselves with the vehicle control dynamics which included practice at main-taining the speed limit, braking, and turning.

The experimental drive occurred over a 6.6 km length of mainly straight arterial road with two or three lanes of traffic ineach direction, intersections every 300–600 m and houses and factories on both sides of the road. Participants were in-structed to drive in accordance with the posted speed limit (70 km/h) except when performing the headway maintenancetask (described below). Based on previous research investigating the potential use of team training programs for young driv-ers (Regan, Salmon, Mitsopoulous, Anderson, & Edquist, 2005), the following positive roles of the passenger were empha-sised: ensuring the driver drives safely (e.g., not speeding, adopting safe following distance); and ensuring hazards aredetected and appropriate action is taken. The experimental drive was divided into two stages to assess these.

The first stage of the drive involved car following, following a lead vehicle at a fixed safe distance, while the speed of thecar in front varied from 60 to 80 km/h at an acceleration rate of 0.3 m/s2. The participant was required to perform two tasks:to maintain a safe gap between the simulator vehicle and the red sedan in front, and to position the simulator vehicle at alltimes in the same lane as the sedan. The second stage of the drive examined response to a potential hazard. The participants’vehicle approached the target intersection with a green traffic signal while an emergency vehicle was heading toward the

Table 2Key learning outcomes and underpinning knowledge, skills and attitudes.

Key learning outcomes � An ability to detect threats to driving safety internal and external to own vehicle� An ability to clearly communicate safety-related information as a passenger participant in an informaldriving team� An ability to positively influence the safe driving behaviour of others

Underpinning knowledge, skills andattitudes

� The concept of teamwork and its benefits to safe driving� The positive role that can be played by passengers� Indicators of unsafe driving behaviour by self� Indicators of unsafe driving behaviour by others� Indicators of passenger behaviour that could threaten safe driving� Performance of a driver support process that can be employed by passengers� Use of strategies to resolve personal disputes in relation to immediate safe driving behaviour� A willingness to be assertive in relation to safe driving� A willingness to constructively contribute to driving safety as a passenger participant in an informaldriving team

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participants’ vehicle from the opposite direction and was programmed to turn across its path. The emergency vehicle wasvisible from about 110 m, with no other traffic to obscure it, and its siren was audible from 150 m. This scenario was adaptedfrom a previous study (Lenné, Triggs, Mulvihill, Regan, & Corben, 2008), which tested participants’ abilities to detect an unex-pected potential hazard and to respond safely. The primary measure of interest was the driver’s speed upon approach to anintersection that involved the rapid emergence of an emergency vehicle. The conversations between driver and passenger inthe simulator were recorded using a digital recorder.

2.4. Training program development and delivery

A training system design consultant was engaged to develop a concept of training for this project. The scope of this train-ing concept included strategies for the effective use of learning methods and media to achieve team training-related learningoutcomes. The learning applicable to this concept included preparatory activities, small group activities and facilitated smallgroup discussion. Following a review of the team training literature (e.g., Salas & Cannon-Bowers, 2000; Salas & Priest, 2004),identification of common elements of team training programs, and its potential relevance to young driver training, the fol-lowing key learning outcomes and underpinning knowledge, skills and attitudes were devised (see Table 2).

On the basis of the learning outcomes and instructional method suggested, it was decided that the team training in thisproject would be delivered in an interactive facilitated group format. The learning outcomes were then used to underpin thedraft facilitator’s training guide. A facilitator’s guide was then developed by a training provider to provide a structured out-line for a 2-h facilitated training session. The primary goal of the training workshop was to teach teamwork and communi-cation skills to young drivers. The workshop began with a discussion about the risk factors of road accidents, including risksthat relate to the effects of carrying passengers. This introduction was followed by group discussions about the importantresponsibilities of both the driver and of the passenger. Participants were presented with possible obstacles to safe out-comes, and they suggested solutions to increase safety. Participants were also introduced to the concept of a team, suchas shared goals, and how this concept could be applied to the driver–passenger relationship. Finally, participants wereencouraged to discuss ways that passengers and drivers could positively influence each other and communicate effectively.As was proposed by Salas and Priest (2004), participants were encouraged to practise their communication skills via roleplays and simulations. During these role plays, participants implemented various strategies for dealing with difficult driversor passengers, such as being assertive rather than threatening.

2.5. Data analysis

For the driving task car following event (stage 1) measures of driving performance (headway, speed, and lateral place-ment) were analysed using t-tests to test for differences across condition (training, control). The measure of hazard response(stage 2) was speed on approach to the target intersection. A two-way ANOVA was conducted with condition (training, con-trol) as a between-groups variable, and distance to intersection as a within-groups variable.

To assess communications the recordings were transcribed verbatim and timings were noted indicating gaps of longerthan 3 s between verbalisations to reflect periods of ‘not talking’. The transcribed conversations were then examined, basedon whether the passenger had promoted either safe driving behaviours, by discouraging the driver’s violation or distractionbehaviour, or unsafe driving behaviour, by encouraging this behaviour. Coding was completed independently by tworesearchers who were blind to the training condition of the pairs, and there was little disagreement on the allocation ofcodes. Any discrepancies were eventually resolved by mutual discussion.

DBQ data were analysed using a 4-way ANOVA with two between-subject factors, Condition (training, control), and Par-ticipant role (driver, passenger), and two within-subject factors, DBQ Item type (violation, lapse, mistake) and Testing time

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(pre or post simulator testing). The specific interactions within the model that were of interest were: Condition by Testingtime; Condition by Participant role by testing time; and Condition by DBQ Item type by Testing time.

3. Results

Post-treatment questionnaires were returned by 23 of the trained participants and 22 of the untrained participants. Therewere no significant differences in the pre-treatment DBQ scores for those participants who returned post-treatment ques-tionnaires and those who did not. All data presented are for the complete dataset.

3.1. Driver Behaviour Questionnaire (DBQ)

The specific interactions of interest within the 4-way ANOVA were not significant. Whether participants received trainingdid not influence the DBQ scores pre and post simulator testing (F(1, 41) = 1.04, p > 0.05), and DBQ scores were not influ-enced by the participants’ role as a driver or passenger (F(1, 41) < 1). As illustrated in Table 3, the mean scores were higheracross the board for the trained participants, confirmed by a main effect of Condition (F(1, 41) = 13.86, p < 0.01).

There was some improvement in self-reported behaviour for the trained participants. For violations, a higher proportionof the trained participants (n = 13) showed improvements, compared to the untrained participants (n = 22; v2(1) = 4.04,p < 0.05). A similar result was found for mistakes: a higher proportion of the trained participants (n = 11) showed improve-ments, compared to the untrained participants (n = 4; v2(1) = 4.64, p < 0.05). For lapses, however, there were no significantdifferences in the proportion of trained (n = 8) and untrained (n = 7) participants who showed improvements. Acknowledg-ing that the scores were higher for the trained group, these data are presented to highlight that some benefit post-trainingbehaviour was observed for the trained participants.

3.2. Driving performance

Mean driving performance measures for the car following task are presented in Table 4. The mean safe headway adoptedby drivers in the trained group was significantly larger than for the control group. Measures of mean and maximum speedwere virtually identical for both trained and untrained groups. Measures of vehicle control (SD Speed, SD Headway, SD Lat-eral Placement) did not differ between groups as expected.

In stage 2 of the drive the participants’ response to the presence of an on-call emergency vehicle was assessed. As illus-trated in Fig. 1, participant pairs who had received the training reduced speed more rapidly upon detection of the oncomingemergency vehicle. This was confirmed by analysis with training condition as the between-groups variable, and distance tointersection as a within-groups variable. Speed was analysed across 10-m distance profiles from 170 m prior to the point atwhich the emergency vehicle crossed the path of own cab (resulting in 18 profile segments). There was a significant Condi-tion by Distance interaction (F(17, 476) = 3.01, p < 0.001), and post hoc t-tests confirmed that speed in the trained group wassignificant lower than for the controls immediately prior to the emergency vehicle turning across (at distance 20 m,t(28) = 2.16, p < 0.05).

Table 3Mean scores on the DBQ by item type (SD in parentheses).

Item type Pre-test DBQ Post-test DBQ

Training Control Training Control

Lapses 1.56 (0.41) 1.08 (0.38) 1.55 (0.24) 1.32 (0.44)Mistakes 1.46 (0.35) 0.81 (0.15) 1.40 (0.24) 1.07 (0.35)Violations 2.35 (0.91) 1.45 (0.76) 2.12 (0.64) 1.66 (0.52)

Table 4Measures of driving performance and statistical tests for the car following task (SD in parentheses).

Performance measure Condition Statistic

Training Control

Mean speed (km/h) 56.1 (5.67) 57.4 (5.72) t(29) = �0.66SD speed (km/h) 24.0 (5.50) 23.8 (3.52) t(29) = 0.13Maximum speed (km/h) 81.1 (4.56) 81.2 (4.42) t(29) = �0.10Mean headway (m) 112.9 (36.83) 87.3 (23.25) t(29) = 2.29*

SD headway (m) 17.7 (8.93) 13.3 (5.56) t(29) = 1.62SD lateral placement (m) 0.361 (0.104) 0.345 (0.091) t(29) = 0.46

* p < 0.05.

Fig. 1. Mean speed (±SD) approaching the intersection for the hazard detection event.

452 M.G. Lenné et al. / Transportation Research Part F 14 (2011) 447–455

3.3. Communication

The communications from seven pairs of passengers were not available for analysis due to technical malfunction. Validdata were derived from 12 trained pairs and 12 untrained pairs. First, the audio transcripts were coded in terms of the per-centage of time that pairs spent conversing in the vehicle, for both scenarios. On average, the trained group (M = 49%) spentless time conversing than did the untrained group (M = 69%, t(25) = 2.22, p < 0.05). The violations that were either encour-aged or discouraged included speeding, running red light, and deliberate braking. The distractions that were commented onincluded actual and potential hazards, such as pedestrians and other road users.

Given two scenarios (car following and emergency vehicle) and two potential behaviours (violation and distraction),there were up to four opportunities to code a passenger as articulating safe comments. Each passenger received a score be-tween zero and four for their safe comments; for example, they scored a full four points only if they discouraged both vio-lation and distraction behaviour in both of the scenarios. Similarly, there were up to four opportunities to code a passenger asexpressing unsafe comments; thus, each passenger received a score between zero and four for their unsafe comments. Eachgroup comprised 12 passengers and thus could achieve in total, up to a score of 48 for safe comments and 48 for unsafe com-ments. The trained passengers scored 33 for safe comments and 12 for unsafe comments, whereas the untrained passengersscored 24 safe comments and 30 for unsafe comments. The differences between the two groups for both safe and unsafecomments were compared by two-sample proportion tests (v2). Compared to the untrained passengers, the trained passen-gers emitted significantly fewer unsafe comments (v2(1) = 14.09, p < 0.01), however, there was no significant difference forsafe comments (v2(1) = 3.52, p > 0.05).

4. Discussion

Team training has been found to be an effective tool for enhancing the performance and processes of teams in a range ofdomains. Well designed team training programs in other safety critical domains have been shown to improve the quality ofteam performance and team processes, such as communication (Salas, Cooke, & Rosen, 2008). Because passengers have pre-viously been found to positively and negatively influence young driver behaviour and safety, forms of team training, highlysuccessful in other safety critical domains, could potentially enhance the positive influences of passengers on young drivers.

In this article we have described an evaluation of a novel training program designed to develop communication and team-work skills in young drivers. To evaluate the effectiveness of the training program in changing behaviour, the trained groupwas compared to an untrained group, with measures of self report real world driving behaviour, simulated driving behav-iour, and driver–passenger communication. It was hypothesised that the trained group would demonstrate safer drivingbehaviour through lower maximum speed and greater mean headway distance, as well as greater hazard detection througha lower approaching mean speed to an emerging hazard, than the untrained group. Finally, it was hypothesised that passen-gers in the trained condition would articulate more safety-related statements and fewer statements encouraging risky driv-ing behaviour.

There was some evidence for positive effects of the training on measures of driving safety. As expected, in the car follow-ing task the driver–passenger pairs in the training group adopted a larger headway when following a lead vehicle. There washowever no effect of training on the maximum speed. The maximum speed adopted in both groups was around 81 km/h

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while the maximum speed of the leading vehicle was 80 km/h. It would appear therefore that both groups displayed appro-priate speed management given that the task involved maintaining a fixed safe distance behind a lead vehicle that had var-iable speed from 60 to 80 km/h. The team training was not expected to influence measures of vehicle control, indicatedthrough variability in speed, lateral placement, and headway. This was confirmed by the analysis. For the hazard detectionevent the participants in the training group also were also quicker to respond to the on-call emergency vehicle cutting acrosstheir path and had a lower mean speed leading up to this point. Together these results provide some evidence for safer andmore cautious driving behaviour in the trained group.

Completion of the pilot training program was not associated with any changes to self-report driving behaviour as mea-sured by the DBQ. While the DBQ scores were consistently higher in the training group, a greater proportion of participantsin the trained group did have improvements in reported mistakes and violations in the post-test assessment compared tocontrols. As attitudes and norms have previously been linked to violation behaviour (Laapotti et al., 2001; Lawton, Parker,Stradling, & Manstead, 1997; Ozkan & Lajunen, 2005), and violations to accident involvement (Ulleberg & Rundmo, 2003;Verschuur & Hurts, 2008), these results provide further support for the need to consider the development of safer attitudesand norms in young driver training programs.

Positive effects of the pilot training program were also noted through differences in driver and passenger communication.The trained driver and passenger pairs spent significantly less time conversing than the untrained group. Further, whenexamining the content of driver and passenger conversations, the trained passengers articulated significantly fewer unsafecomments than the untrained passengers. Given that training of communication skills can improve team processes and per-formance in other domains such as aviation (Kanki & Smith, 2001), this positive finding should be explored further.

Focussing safety interventions on the driver–passenger cohort opens up other key areas of further research. Popular teamconcepts such as shared cognition (Salas & Fiore, 2004), distributed situation awareness (Salmon, Stanton, Walker, & Jenkins,2009) and shared mental models (Fox, Code, & Langfield-Smith, 2000) are key concepts that offer opportunity to enhanceperformance during collaborative endeavour; however, because of the traditional driver centric focus of research in this area,such concepts have been neglected to date, despite their relevance to enhancing performance and safety. Distributed situ-ation awareness theory, for example, would argue that drivers and passengers have very different situation awareness dur-ing driving and therefore that the compatibility between the two individuals is particularly important. Supporting theappropriate and timely exchange of awareness between passengers and drivers is therefore critical. Further research istherefore required, first, too understand these concepts in a driver–passenger team context and, second, to use these con-cepts to derive further driver passenger program training needs. Finally, as well as communications, additional measuresof team process and performance are urged in a driving context. In addition to measures of driver passenger situation aware-ness, important elements known to underpin collaborative performance should also be considered, including leadership,coordination, mutual performance monitoring, back up behaviour, adaptability, shared mental models, and mutual trust(Salas, Sims & Burke, 2005).

There is a growing body of research from across the safety critical domains that suggest team training is effective forincreasing the quality of team processes and overall team performance (Salas et al., 2008). The present study shows the po-tential positive effects on safety and performance when young driver–passenger cohorts are considered collectively as adriving ‘team’, and are given training on the some of the skills required for efficient teamwork. The training program testedshares some similarities with components of Crew Resource Management (CRM) training, a popular form of team trainingused in other areas to train key teamwork competencies such as assertiveness, shared situation awareness and communica-tions (Salas et al., 2008). Originally used in aviation, this form of training has since been applied in a plethora of safety criticaldomains, ranging from offshore oil production (O’Connor & Flin, 2003) and healthcare (Howard, Gaba, Fish, Yang, & Sarn-quist, 1992) to air traffic control (Schmeiser, Bömmel, & Bühren, 2000) and rail. Although difficult to assess, the evidencegenerally suggests that CRM is effective (Salas et al., 2008). The findings from this study suggest CRM style training, focussedon key driver–passenger team competencies, could potentially play a key role in enhancing young driver–passenger teamsafety and performance. Various studies have demonstrated that traditional driver education programs have had little effecton young driver safety (e.g., Ker et al., 2005); new, evidence-based approaches are required. Given its success in other do-mains, appropriately tailored CRM training programs might represent the paradigm shift needed in driver training. Thedevelopment and evaluation of a full driving CRM training program, focussing on the range of driver–passenger team skillsrequired for safe driving, is a logical future line of inquiry to arise from this study.

As a proof of concept study the research reported in this article does have limitations and there are clear avenues for fur-ther research. A follow-up driving test, around the time the second DBQ was administered, would potentially have providedsupport for the maintenance of the training benefit over a longer time period. In addition to being more robust, additionalfollow up testing, perhaps in combination with an alternative to the training session for the control participants, would lar-gely eliminate any potential differential Hawthorne effect across the training and control groups. Regarding self-reportedbehaviours, the DBQ is a well-accepted research tool but, not surprisingly, is not designed to capture all of the relevant mis-takes and violations that might arise from driver–passenger interactions. This mismatch, along with the significantly greaterweekly driving reported by the trained participants, may explain the lack of any training effect on these measures. The devel-opment of a validated self-report tool is an important requirement for future work in this area.

Further, the design was deliberately limited in its scope. For example, the recruitment of participants was restricted to aspecific demographic: male, university students, who were probationary drivers. The restriction to male drivers wasmotivated by the crash data and findings that female passengers are more likely than males to tell the driver when they felt

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unsafe in the car (Ulleberg, 2004). Further, the study measured behaviour using a limited range of behavioural and self-re-port measures in a laboratory environment that cannot replicate the social pressures present when driving at night withpeer-age passengers.

In conclusion, although the workshop in this study was tested on a relatively small sample size, measurable improve-ments in the behaviours of young drivers were found. The results open the possibility to an alternative view of young pas-sengers, indicating that young passengers may also act as a positive influence and as a useful resource for the driver. Thepresence of positive, helpful passengers would be particularly important for novice drivers in the first few months of driving,where an additional resource could be most beneficial. An important next step is to establish the program effects over a lar-ger range of measures known to be important for young drivers. Such a program might also be enhanced by the provision offeedback to drivers (Hutton, Sibley, Harper, & Hunt, 2002) or the use of commentary training (Crundall, Andrews, van Loon, &Chapman, 2010). Whether the training described here would have similar effects in the long-term, in other populations (e.g.,female drivers, learner drivers, and high school students), and in the real world, are issues that deserve further investigation.It appears however there is potential for such training to complement the continued supervision of young drivers by expe-rienced and responsible mentors such as their parents.

Acknowledgements

The present study was supported by a Grant from the NRMA-ACT Road Safety Trust. We are grateful to Tony and TerryNorquay, from Norquay Training & Development, who developed the facilitator’s guide and ran the workshops. We would alsolike to thank Gayle Di Pietro, Phil Wallace, Eve Mitsopoulos, Amy Williamson and Nebojsa Tomasevic for their contributionsto the project. Paul Salmon’s involvement was supported by a National Health and Medical Research Council Public Healthpost doctoral training fellowship.

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