Maturation of Driving Skill from Teen to Young Adult to Experienced Adult using SHRP2 Naturalistic Data

Principal Investigator: Thomas Seacrist, MBE, Children’s Hospital of Philadelphia

Below is an executive summary of this project. Please note that this summary describes results and interpretation that may not be final. Final interpretation of results will be in the peer-reviewed literature.

 Comparison of the miles driven, crashes, and crash rates among novice teens, young adults, and experienced adults.


Motor vehicle crashes are the leading cause of death for young adult drivers 20-24 years old.  Limited research has been conducted on the transition from novice to experienced driving.  It is important to understand how driving skill improves with age and experience to help identify which errors persist into early adulthood. 


To expand upon previously collected SHRP2 data on novice teen (16-19 yrs) and experienced adult (35-54 yrs) drivers by quantifying factors contributing to crashes and near crashes among young drivers (20-24 yrs) using naturalistic driving data and comparing these factors across age. 


Crash and near crash data for young adult drivers were be collected from the SHRP2 database.  Crashes and near crashes were classified via scene video review.  Crash and near crash rates will be calculated per miles driven.  Rear-end crash and near crash vehicle dynamics including crash severity, impact velocity, and near crash severity, were computed.  These findings were be compared to previously collected CChIPS data from teen (16-19 yrs) and adult (35-50 yrs) drivers. 


Young adults exhibited some improvement in overall crash rates compared to novice teens, but their crash rate was more similar to novice teens than experienced adults.  Unlike novice teens and experienced adults who were involved in rear-end crashes most often, the most common crash mode for young adults was road departures.  Young adult crash severity and impact velocity fell in between that of novice teens and experienced adults, suggesting that young adults are involved in less severe crashes, but still of greater severity than experienced drivers.


These data provide crash rates measured in a naturalistic driving setting that is inclusive of all crashes, not just fatal and police-reported crashes, as well as a reliable method for capturing driving exposure.  This study will advance the safety of young adult drivers by providing data that can be used by vehicle manufacturers to optimize active safety systems for age-specific driving skill deficits, thus decreasing overall crash risk among young drivers. 

Project Team Member

Helen Loeb, PhD, Children's Hospital of Philadelphia


Ethan Douglas, The University of Pennsylvania; Ayya Elzarka, The University of Pennsylvania; Charles Gottlieb, Jack M. Barrack Hebrew Academy; Leora Haber, Princeton University; Abe Kashem, The University of Pennsylvania; Taryn McKinney, University of Pennsylvania; James Megariotis, Drexel University; Danielle Mendoza, Widener University; Danielle Mendoza, Widener University; Adin Solomon, Jack M. Barrack Hebrew Academy;

IAB Mentors

Douglas Longhitano, American Honda Motor Co., Inc.; Zine Ben Aou, FCA US LLC; Melissa Miles, State Farm Mutual Automobile Insurance Company; Schuyler St. Lawrence, Toyota USA; Uwe Meissner, Technical Advisor