The 40-Teen Naturalistic Teenage Driving Study (NTDS)
The purpose of NTDS was to examine the driving performance of novice teenage drivers. Researchers recruited 40 novice teen drivers at the time of licensure and equipped the teens' vehicles with cameras, gravitational force (g-force) meters, Global Positioning Systems (GPS), and other equipment to provide detailed information about driving performance during the first 18 months of driving experience. During the first 18 months of driving, we examined rates of elevated g-force events, crashes and near crashes, and other driving performance measures and contributing factors, such as speed and secondary task engagement. Because many study participants shared a vehicle with a parent, we compared rates of novice teenagers with their parents.
Supervised Practice Driving Study
This study examined parent-supervised practice driving and the extent to which the amount of practice was associated with driving performance after licensure. A sample of 92 teens and at least 1 parent was recruited and observed during the supervised practice driving period and 12 months after licensure. Driving was assessed using GPS, multiple cameras, and accelerometers. Audio transcripts of parent-teen interactions were examined to determine how parents taught their teenage children to drive.
Experimental Research on the Influence of Peer Passengers on Simulated Risky Driving Among Teenage Males
The objective of these studies was to understand the effects and mechanisms of the influence of peer passengers on male teen drivers, specifically the effects of peer personality stereotypes on the risk-taking behavior of male teenage drivers. Experimental studies were conducted in a driving simulator with various manipulations of passenger type and presence. Driving simulator and eye- tracking data were collected to analyze driving behavior, risk taking behavior, and attention/distraction related variables.
The Uniform Naturalistic Driving Study (UNDS)
One of the limitations of naturalistic research to date has been small sample size. Larger samples are needed for analyses of risk by driving conditions and among subgroups. Toward this end, the UNDS obtained data from the Strategic Highway Research Program 2 (SHRP2) Naturalistic Driving Study, which used the same instrumentation as the NTDS and Supervised Practice Driving Study. SHRP2 obtained driving data from more than 200 novices and another 600 adult drivers, which we combined with the data from the NICHD NTDS (n=42) and Supervised Practice Driving Study (n=90). The large combined data set allowed subgroup analyses and allowed us to answer key questions, such as:
- What are individual level predictors of risky driving?
- Does crash risk and risky driving vary according to driving conditions?
- What is the effect on driving outcomes of the type of passengers and driving context?
- What is the relationship between risky driving behavior and crash risk?
- To what extent does a small proportion of high-risk drivers account for the overall high crash risk of young drivers?
The Effect of Teenage Passengers on Teenage Simulated Driving Performance (Teen Passenger Study)
The presence of teenage passengers has been shown to increase crash risk. Notably, Ouimet et al. (2010) reported that male teenage passengers increased fatal crash risk not only among teenage but also among young adult drivers, particularly male drivers. In previous research, we observed vehicles exiting high school parking lots and found that teenage drivers with male teenage passengers drove faster and closer to the lead vehicle than other drivers (Simons-Morton, Lerner, & Singer, 2005). However, in the NTDS, we found that teen passengers (including males and females) provided a slightly protective effect on crash/near crash and risky driving compared to the no passenger condition.
The Teen Passenger Study 1 (TPS1), completed in the spring of 2012, was designed to ascertain the effect of a risk-accepting or risk-averse teenage passenger on teenage risky driving. We recruited 66 newly licensed male teenage drivers and randomized them to risk-accepting or risk-averse passenger conditions. The passenger was a trained, male confederate. We were interested in the effect of social norms on driving behavior, so we employed a pre-drive priming task in which the participant and confederate passenger watched a video of risky driving and the confederate passenger verbalized that he would or would not, depending on the role he was playing, ever ride with that driver. We used a randomized block design with two conditions (passenger: risk-accepting vs. risk-averse) X two drive orders (driving alone first vs. driving with the passenger first). T-test comparisons of difference scores (passenger minus alone) were in the expected direction favoring greater driving risk in the risk-accepting passenger group. We concluded that teenage drivers exposed to a risk-accepting teenage passenger were less likely to stop at red lights (p=0.04) while driving in a simulator and this risky behavior was greater in the presence of a risk-accepting than a risk-averse peer passenger (Simons-Morton et al., Health Psychology, 2014).
In other analyses of TPS1 neuroimaging data, we found participants who were sensitive to social exclusion, measured by a task in which confederate peers played a computer cyber “catch” game, Cyberball, with the participant while he was imaged. Gradually, the confederates excluded the participant and the imaging indicated painful exclusion. We found that participants who were sensitive to social exclusion according to neuro-imaging data were also sensitive to passenger presence when driving the simulator a week later (Falk et al., The Journal of Adolescent Health, 2014).
The TPS2 tested the effect of teenage peer pressure on teenage risky driving performance. The study design was similar to TPS1, except we put the drivers under pressure by instructing them to reach a particular destination within a limited time without error. The confederate passenger served as the navigator and at key points in the drive, verbally encouraged the driver to hurry (in the role of a risk-accepting teen) or make no errors (in the role of a risk-averse teen). Assessment of fMRI and psychosocial tasks was also conducted. Preliminary analyses indicated that the study participant drove in a riskier manner in the presence of a peer exerting mild pressure to engage in risk, compared with in the presence of a confederate passenger who exerted mild pressure not to take risk ( Bingham et al., Transportation Research, Part F: Traffic Psychology and Behaviour, 2016).
TPS3 found that pre-drive mood was associated with risky simulated driving in the presence of a peer passenger. Participants were randomized to play a mood- enhancing guitar game with the confederate passenger prior to driving in the simulator, or to sit with a confederate peer listening to quiet music (Simons-Morton et al., Proceedings of the 8th International Driving Symposium on Human Factors in Driver Assessment, Training, and Vehicle Design, 2015).
TPS4 tested how teenage passengers might influence risky driving, particularly in certain mental states. In this study, we randomized teenage drivers to be socially excluded or included when playing Cyberball. Two studies examined simulated intersection management among young drivers after they were socially excluded during Cyberball. In Study 1, risky driving was significantly greater among excluded males driving with a risk-accepting vs. passive passenger; no effect of social exclusion. In Study 2, risky driving was significantly greater among excluded females driving with a risk-accepting vs. a passive passenger, and greater among those included vs. excluded when driving with a risk-accepting passenger. Risky driving behavior among male and female teenagers may be influenced uniquely by passenger norms and social inclusion.
Division Collaborators
- Denise Haynie, Ph.D., M.P.H.
- Bruce Simons-Morton, Ed.D., M.P.H. (Scientist Emeritus)
Extramural Collaborators
- Johnathon Ehsani, Ph.D., Johns Hopkins Bloomberg School of Public Health
- Kaigang Li, Ph.D., Colorado State University
Selected Publications
- Gershon, P., Ehsani, J. P., Klauer, S., Zhu, C., Dingus, T., & Simons-Morton, B. G. (2018). Crash risk and risky driving behavior among adolescents during learner and independent driving periods. Journal of Adolescent Health, 63(5), 568-574. PMID: 30006026
- Li, Q., Guo, F., Kim, I., Klauer, S. G., & Simons-Morton, B. G. (2018). A Bayesian finite mixture change-point model for assessing the risk of novice teenage drivers. Journal of Applied Statistics, 45(4), 604-625. PMID: 29375174
- Li, Q., Guo, F., Klauer, S. G., & Simons-Morton, B. G. (2017). Evaluation of risk change-point for novice teenage drivers. Accident Analysis & Prevention, 108, 139-146. PMID: 28881279
- Gershon, P., Zhu, C., Klauer, S. G., Dingus, T., & Simons-Morton, B. (2017). Teens’ distracted driving behavior: Prevalence and predictors. Journal of Safety Research, 63, 157-161. PMID: 29203014
- Ehsani, J. P., Li, K., Grant, B. J. B., Gershon, P., Klauer, S. G., Dingus, T. A., & Simons-Morton, B. (2017). Factors influencing learner permit duration. Safety, 3(1), pii-2. PMID: 29057255
- Ehsani, J. P., Haynie, D., Ouimet, M. C., Zhu, C., Guillaume, C., Klauer, S. G., Dingus, T., & Simons-Morton, B. G. (2017). Teen drivers’ awareness of vehicle instrumentation in naturalistic research. Journal of Safety Research, 63, 127-134. PMID: 29203010
- Ehsani, J. P., Klauer, S. G., Zhu, C., Gershon, P., Dingus, T. A., & Simons-Morton, B. G. (2017). Naturalistic assessment of the learner license period. Accident Analysis & Prevention 106, 275-284. PMID: 28654843
- Simons-Morton, B. (2017). Driving in search of analyses. Statistics in Medicine, 36(24), 3763-3771. PMID: 28699210
- Cascio, C. N., O'Donnell, M. B., Simons-Morton, B. G., Bingham, C. R., & Falk, E. B. (2017). Cultural context moderates neural pathways to social influence. Culture and Brain, 5(1), 50-70. DOI: 10.1007/s40167-016-0046-3
- O'Brien, F., Bible, J., Liu, D., & Simons-Morton, B. G. (2017). Do young drivers become safer after being involved in a collision? Psychological Science, 28(4), 407-413. PMID: 28406372
- Klauer, S. G., Ehsani, J., & Simons-Morton, B. (2017). Using naturalistic driving methods to study novice drivers. In D. L. Fisher, J. K. Caird, W. J. Horrey, L. M. Trick (Eds), Handbook of teen and novice drivers: Research, practice, policy, and directions. (pp. 239-256). Boca Raton, FL: CRC Press.
- Simons-Morton, B., & Ouimet, M. C. (2017). Teen driving risk in the presence of passengers. In D. L. Fisher, J. K. Caird, W. J. Horrey, L. M. Trick (Eds), Handbook of teen and novice drivers: Research, practice, policy, and directions. (pp 409-420). Boca Raton, FL: CRC Press.
- Simons-Morton, B., Li, K., Ehsani, J., & Vaca F. E. (2016). Co-variability in three dimensions of teenage driving risky behavior: Impaired driving, risky and unsafe driving behavior, and secondary task engagement. Traffic Injury Prevention, 17(5), 441-446. PMID: 26514232
- O'Brien, F., Klauer, S. G., Ehsani, J., & Simons-Morton, B. G. (2016). Changes over 12 months in eye glances during secondary task engagement among novice drivers. Accident Analysis & Prevention, 93, 48-54. PMID: 27177392
- Simons-Morton, B., & Ehsani, J. P. (2016). Learning to drive safely: Reasonable expectations and future directions for the learner period. Safety,2(4), pii -20. PMID: 29057254
- Bingham, C. R., Simons-Morton, B. G., Pradhan, A. K., Li, K., Almani, F., Falk, E. B., Shope, J. T., Buckley, L., Ouimet, M. C., & Albert, P. S. (2016). Peer passenger norms and pressure: Experimental effects on simulated driving among teenage males. Transportation Research, Part F: Traffic Psychology and Behaviour, 41(A), 124-137. PMID: 27818610
- Tran, V., Liu, D., Pradhan, A. K., Li, K., Bingham, C. R., Simons-Morton, B. G., & Albert, P. S. (2015). Assessing risk-taking in a driving simulator study: Modeling longitudinal semi-continuous driving data using a two-part regression model with correlated random effects. Analytic Methods in Accident Research, 5-6,17-27. PMID: 26894036
- Ehsani, J. P., Li, K., Simons-Morton, B. G., Fox Tree-McGrath, C., Perlus, J. G., O'Brien, F., & Klauer, S. G. (2015). Conscientious personality and young drivers’ crash risk. Journal of Safety Research, 54, 83-87. PMID: 26403906
- Simons-Morton, B. G., Klauer, S. G., Ouimet, M. C., Guo, F., Albert, P. S., Lee, S. E., Ehsani, J. P., Pradhan, A. K., & Dingus, T. A. (2015). Naturalistic Teenage Driving Study: Findings and lessons learned. Journal of Safety Research, 54, 41-44. PMID: 26403899
- Ouimet, M. C., Pradhan, A. K., Brooks-Russell, A., Ehsani, J. P., Berbiche, D., & Simons-Morton, B. G. (2015). Young drivers and their passengers: A systematic review of epidemiological studies on crash risk. The Journal of Adolescent Health, 57(1 Suppl), S24-S35.e6. PMID: 26112735
- Simons-Morton, B. G., Bingham, C. R., Shope, J. E. F., Ouimet, M. C., Pradhan, A. K., & Li, K. (2015). The effect of emotion on teenage passenger effects on teenage simulated driving risk. In Proceedings of the 8th International Driving Symposium on Human Factors in Driver Assessment, Training and Vehicle Design. Iowa City, Iowa: University of Iowa.
- Cascio, C. N., Carp, J., O'Donnell, M. B., Tinney Jr., F. J., Bingham, C. R., Shope, J. T., Ouimet, M. C., Pradhan, A. K., Simons-Morton, B. G., & Falk, E. B. (2015). Buffering social influence: Neural correlates of response inhibition predict driving safety in the presence of a peer. Journal of Cognitive Neuroscience, 27(1), 83-95. PMID: 25100217
- Ehsani, J. P., Simons-Morton, B., Xie, Y., Klauer, S. G., & Albert, P. S. (2014). The association between kinematic risky driving among parents and their teenage children: Moderation by shared personality characteristics. Accident Analysis & Prevention, 69, 56-61. PMID 24745931
- Lambert, A. E., Simons-Morton, B. G., Cain, S. A., Weisz, S., & Cox, D. J. (2014). Considerations of a dual-systems model of cognitive development and risky driving. Journal of Research on Adolescence, 24(3), 541-550. PMID: 25983529
- Ouimet, M. C., Brown, T. G., Guo, F., Klauer, S. G., Simons-Morton, B. G., Fang, Y., Lee, S. E., Gianoulakis, C., & Dingus, T. A. (2014). Higher crash and near-crash rates in teenaged drivers with lower cortisol reactivity: An 18-month longitudinal, naturalistic study. Journal of the American Medical Association Pediatrics, 168(6), 517-522. PMID: 24710522
- Falk, E. B., Cascio, C. N., O'Donnell, M. B., Carp, J., Tinney Jr., F. J., Bingham, C. R., Shope, J. T., Ouimet, M. C., Pradhan, A. K., & Simons-Morton, B. G. (2014). Neural responses to exclusion predict susceptibility to social influence. The Journal of Adolescent Health, 54(5 Suppl), S22-S31. PMID: 24759437
- Simons-Morton, B. G., Bingham, C. R., Falk, E. B., Li, K., Pradhan, A., Ouimet, M. C., Almani, F., & Shope, J. (2014). Experimental effects of injunctive norms on simulated risky driving among teenage males. Health Psychology, 33(7), 616-627. PMID: 24467258
- Pradhan, A. K., Li, K., Bingham, C. R., Simons-Morton, B. G., Ouimet, M. C., & Shope, J. T. (2014). Peer passenger influences on male adolescent drivers’ visual scanning behavior during simulated driving. The Journal of Adolescent Health, 54(5 Suppl), S42-S49. PMID: 24759440
- Simons-Morton, B. G., Guo, F., Klauer, S. G., Ehsani, J. P., & Pradhan, A. K. (2014). Keep your eyes on the road: Young driver crash risk increases according to duration of distraction. The Journal of Adolescent Health, 54(5 Suppl), S61-S67. PMID: 24759443
- Klauer, S. G., Guo, F., Simons-Morton, B. G., Ouimet, M. C., Lee, S. E., & Dingus, T. A. (2014). Distracted driving and risk of road crashes among novice and experienced drivers. The New England Journal of Medicine, 370(1), 54-59. PMID: 24382065
- Kim, S., Chen, Z., Zhang, Z., Simons-Morton, B. G., & Albert, P. S. (2013). Bayesian hierarchical poisson regression models: An application to a driving study with kinematic events. Journal of the American Statistical Association, 108(502), 494-503. PMID: 24076760
- Ouimet, M. C., Pradhan, A. K., Simons-Morton, B. G., Divekar, G., Mehranian, H., & Fisher, D. L. (2013). The effect of male teenage passengers on male teenage drivers: Findings from a driving simulator study. Accident Analysis & Prevention, 58, 132-139. PMID: 23727554
- Guo, F., Simons-Morton, B. G., Klauer, S. E., Ouimet, M. C., Dingus, T. A., & Lee, S. E. (2013). Variability in crash and near-crash risk among novice teenage drivers: A naturalistic study. The Journal of Pediatrics, 163(6), 1670-1676. PMID: 23992677
- Simons-Morton, B. G., Bingham, C. R., Ouimet, M. C., Pradhan, A. K., Chen, R., Barretto, A., & Shope, J. (2013). The effect on teenage risky driving of feedback from a safety monitoring system: A randomized controlled trial. The Journal of Adolescent Health, 53(1), 21-26. PMID: 23375825
- Zakrajsek, J. S., Shope, J. T., Greenspan, A. I., Wang, J., Bingham, C. R., & Simons-Morton, B. G. (2013). Effectiveness of a brief parent-directed teen driver safety intervention (Checkpoints) delivered by driver education instructors. The Journal of Adolescent Health, 53(1), 27-33. PMID: 23481298
- Simons-Morton, B. G., Cheon, K., Guo, F., & Albert, P. (2013). Trajectories of kinematic risky driving among novice teenagers. Accident Analysis & Prevention, 51, 27-32. PMID: 23182780
- Jackson, J. C., Albert, P. S., Zhang, Z., & Simons-Morton, B. (2013). Ordinal latent variable models and their application in the study of newly licensed teenage drivers. Journal of the Royal Statistical Society, Series C: Applied Statistics, 62(3), 435-450. PMID: 25284899
- Simons-Morton, B. G., Ouimet, M. C., Chen, R., Klauer, S. G., Lee, S. E., Wang, J., & Dingus, T. A. (2012). Peer influence predicts speeding prevalence among teenage drivers. Journal of Safety Research, 43(5-6):397-403. PMID: 23206513
- Zhang, Z., Albert, P. S., & Simons-Morton, B. G. (2012). Marginal analysis of longitudinal count data in long sequences: Methods and application to a driving study. The Annals of Applied Statistics, 6(1):27-54. PMID: 27087885
- Simons-Morton, B. G., Zhang, Z., Jackson, J. C., & Albert, P. S. (2012). Do elevated gravitational-force events while driving predict crashes and near crashes? American Journal of Epidemiology, 175(10):1075-1079. PMID: 22271924