Strategies to Improve Reporting of Impaired and Distracted Driving in Motor Vehicle Crashes (2026)
Chapter: Front Matter
GOVERNORS HIGHWAY SAFETY ASSOCIATION RESEARCH COMMITTEE*
CO-CHAIRS
Karson James
Wyoming Department of Transportation
Tim Kerns
Maryland Motor Vehicle Administration
MEMBERS
Amy Boggs
West Virginia Governorʼs Highway Safety Program
Joel Brisson
Tennessee Highway Safety Office
Mark Ezzell
North Carolina Governorʼs Highway Safety Program
Brian Harmon
Minnesota Department of Public Safety
Lissette Morgan
Arizona Governorʼs Office of Highway Safety
Flavia Pereira
Connecticut Department of Transportation
Max Tyler Roberts
Washington Traffic Safety Commission
Emily Thomas
South Carolina Office of Highway Safety and Justice Programs
__________________________
* Membership as of February 2026.
TRANSPORTATION RESEARCH BOARD 2026 EXECUTIVE COMMITTEE*
OFFICERS
Chair: Joel M. Jundt, Secretary of Transportation, South Dakota Department of Transportation, Pierre
Vice Chair: Randell Iwasaki, President and CEO, Iwasaki Consulting Services, Walnut Creek, CA
Executive Director: Victoria Sheehan, Transportation Research Board, Washington, DC
MEMBERS
James F. Albaugh, President and CEO, The Boeing Company (retired), Scottsdale, AZ
Marsha Anderson Bomar, Strategic Transportation Advisor, GHD, Duluth, GA
Douglas C. Ceva, Vice President, Customer Lead Solutions, Prologis, Inc., Jupiter, FL
Nancy Daubenberger, Commissioner of Transportation, Minnesota Department of Transportation, St. Paul
Garrett Eucalitto, Commissioner, Connecticut Department of Transportation, Newington
Andrew Fremier, Executive Director, Metropolitan Transportation Commission, San Francisco, CA
Martha Grabowski, Professor Emerita, Information Systems, Le Moyne College, Madden College of Business and Economics, Cazenovia, NY
Edward Hassinger, Director, Missouri Department of Transportation, Jefferson City
Shante Hastings, Cabinet Secretary, Delaware Department of Transportation, Dover
Carol A. Lewis, Professor, Transportation Studies, Texas Southern University, Houston
Ricardo Martinez, Adjunct Professor of Emergency Medicine, Emory University School of Medicine, Decatur, GA
Russell McMurry, Commissioner, Georgia Department of Transportation, Atlanta
Craig E. Philip, Research Professor and Director, VECTOR, Department of Civil and Environmental Engineering, Vanderbilt University, Nashville, TN
Steward T.A. Pickett, Distinguished Senior Scientist, Cary Institute of Ecosystem Studies, Millbrook, NY
Leslie S. Richards, Professor of Practice, University of Pennsylvania, Philadelphia
Tracy Larkin Thomason, Director, Nevada Department of Transportation, Carson City
Marc Williams, Executive Director, Texas Department of Transportation, Austin
EX OFFICIO MEMBERS
Derek Barrs, Administrator, Federal Motor Carrier Safety Administration, Washington, DC
Steven G. Bradbury, Deputy Secretary, U.S. Department of Transportation, Washington, DC
Stephen Carmel, Administrator, U.S. Maritime Administration, Washington, DC
Tara Cavalline, Professor, University of North Carolina, Charlotte, and Chair, TRB Technical Activities Council
David Fink, Administrator, Federal Railroad Administration, Washington, DC
Firas Ibrahim, Director, Office of Research, Development, and Technology, Office of the Assistant Secretary for Research and Technology, Washington, DC
Jason Kelly, Deputy Commanding General for Civil Works and Emergency Operations, U.S. Army Corps of Engineers, Washington, DC
Sandra Knight, President, WaterWonks, LLC, Washington, DC, and Chair, TRB Marine Board
Sean McMaster, Administrator, Federal Highway Administration, Washington, DC
Marcus J. Molinaro, Administrator, Federal Transit Administration, Washington, DC
Jonathan Morrison, Administrator, National Highway Traffic Safety Administration, Washington, DC
Seval Oz, Senior Advisor, Office of the Assistant Secretary for Research and Technology, Washington, DC
Niloo Parvinashtiani, Engineer, Mobility Consultant Solutions, Iteris Inc., Fairfax, VA, and Chair, TRB Young Participants Council
Paul Roberti, Administrator, Pipeline and Hazardous Materials Safety Administration, Washington, DC
Paul P. Skoutelas, President and CEO, American Public Transportation Association, Washington, DC
Jim Tymon, Executive Director, American Association of State Highway and Transportation Officials, Washington, DC
__________________________
* Membership as of February 2026.
BEHAVIORAL TRAFFIC SAFETY COOPERATIVE RESEARCH PROGRAM
BTSCRP RESEARCH REPORT 19
Strategies to Improve Reporting of Impaired and Distracted Driving in Motor Vehicle Crashes
Adam Francour
Andrea Bill
David A. Noyce
University of Wisconsin–Madison
Madison, WI
Bob Scopatz
Kathleen Haney
Vanasse Hangen Brustlin (VHB)
Raleigh, NC
Xiao Qin
Yang Li
University of Wisconsin–Milwaukee
Milwaukee, WI
Subscriber Categories
Highways • Safety and Human Factors
Research sponsored by the Governors Highway Safety Association and National Highway Traffic Safety Administration
2026
BEHAVIORAL TRAFFIC SAFETY COOPERATIVE RESEARCH PROGRAM
Since the widespread introduction of motor vehicles more than a century ago, crashes involving their operation remain a significant public health concern. While there have been enormous improvements in highway design and construction, as well as motor vehicle safety, which have been instrumental in lowering the rate of crashes per million miles in the United States, more than 35,000 people die every year in motor vehicle crashes. In far too many cases, the root causes of the crashes are the unsafe behaviors of motor vehicle operators, cyclists, and pedestrians. Understanding human behaviors and developing effective countermeasures to unsafe ones is difficult and remains a major weakness in our traffic safety efforts.
The Behavioral Traffic Safety Cooperative Research Program (BTSCRP) develops practical solutions to save lives, prevent injuries, and reduce costs of road traffic crashes associated with unsafe behaviors. BTSCRP is a forum for coordinated and collaborative research efforts. It is managed by the Transportation Research Board (TRB) under the direction and oversight of the Governors Highway Safety Association (GHSA) with funding provided by the National Highway Traffic Safety Administration (NHTSA). Funding for the program was originally established in Moving Ahead for Progress in the 21st Century (MAP-21), Subsection 402(c), which created the National Cooperative Research and Evaluation Program (NCREP). Fixing Americaʼs Surface Transportation (FAST) Act continued the program. In 2017, GHSA entered into an agreement with TRB to manage the research activities, with the program name changed to Behavioral Traffic Safety Cooperative Research Program. The GHSA Executive Board serves as the governing board for the BTSCRP. The Board consists of officers, representatives of the 10 NHTSA regions, and committee and task force chairs. The Research Committee Chair appoints committee members who recommend projects for funding and provide oversight for the activities of BTSCRP. Its ultimate goal is to oversee a quality research program that is committed to addressing research issues facing State Highway Safety Offices. The Executive Board meets annually to approve research projects. Each selected project is assigned to a panel, appointed by TRB, which provides technical guidance and counsel throughout the life of the project. The majority of panel members represent the intended users of the research projects and have an important role in helping to implement the results. BTSCRP produces a series of research reports and other products such as guidebooks for practitioners. Primary emphasis is placed on disseminating BTSCRP results to the intended users of the research: State Highway Safety Offices and their constituents.
BTSCRP RESEARCH REPORT 19
Project BTS-20
ISSN 2766-5976 (Print)
ISSN 2766-5984 (Online)
ISBN 978-0-309-60317-1
Library of Congress Control Number 2026934524
© 2026 by the National Academy of Sciences. National Academies of Sciences, Engineering, and Medicine and the graphical logo are trademarks of the National Academy of Sciences. All rights reserved.
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NOTICE
The research report was reviewed by the technical panel and accepted for publication according to procedures established and overseen by the Transportation Research Board and approved by the National Academies of Sciences, Engineering, and Medicine.
This material is based upon work sponsored by the Governors Highway Safety Association in cooperation with the National Highway Traffic Safety Administration under Agreement No. DTNH2216H00018 or 693JJ92250010. Any opinions, findings, and conclusions or recommendations expressed or implied in this document are those of the researchers who performed the research and are not necessarily those of the Transportation Research Board; the National Academies of Sciences, Engineering, and Medicine; or the program sponsors.
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BEHAVIORAL TRAFFIC SAFETY COOPERATIVE RESEARCH PROGRAM
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COOPERATIVE RESEARCH PROGRAMS
CRP STAFF FOR BTSCRP RESEARCH REPORT 19
Monique R. Evans, Director, Cooperative Research Programs
Waseem Dekelbab, Deputy Director, Cooperative Research Programs
Richard A. Retting, Acting Manager, Behavioral Traffic Safety Cooperative Research Program
Tijhuana Stapleton, Senior Program Assistant
Natalie Barnes, Director of Publications
Brian Haefs, Associate Director of Publications
BTSCRP PROJECT BTS-20 PANEL
James Carlton Fell, James C Fell Consulting LLC, Annandale, VA (Chair)
Patrick A. Byrne, Ontario Ministry of Transportation, Toronto, ON
Rob Duckworth, R.I.S.C., LLC, Greensburg, IN
Eric Glick, Carson City, NV
Michael J. Hanson, Minnesota Department of Public Safety, St. Paul, MN
Chanyoung Lee, USF Center for Urban Transportation Research, Tampa, FL
Maria Rella Riccardi, University of Naples Federico II, Naples, Italy
Christopher J. Turner, Kansas Third District Judicial Court, Topeka, KS
Stacy Jeleniewski, NHTSA Liaison
Bernardo B. Kleiner, TRB Liaison
FOREWORD
By Richard A. Retting
Staff Officer
Transportation Research Board
BTSCRP Research Report 19: Strategies to Improve Reporting of Impaired and Distracted Driving in Motor Vehicle Crashes provides procedures for determining the extent of misreporting impaired and distracted driving crashes, as well as methods to improve the reporting of impaired and distracted driving in motor vehicle crashes. Misreporting comprises a variety of issues, including underreporting, overreporting, errors in crash data recording, and misclassification. Guidance and methodologies developed as part of this research will help states and local jurisdictions identify the misreporting of impaired and distracted driving and improve crash data collection and analysis. This report will be of interest to state highway safety offices and other stakeholders concerned with improving the reporting of impaired and distracted driving in motor vehicle crashes.
Statistical and analytical models have been widely used to predict the counts and probabilities of crashes at roadway locations with historical crash data. Estimating unbiased models is critical in accurately predicting the counts and probabilities of crashes and allocating funds for traffic safety improvement. However, underreporting or overreporting certain behaviors in crash data, specifically alcohol and/or drug-impaired driving and distracted driving, may result in problematic model estimation results. Underreporting and overreporting impaired and distracted driving can also affect other areas that rely on reported crash data, such as drug recognition expert training, high-visibility enforcement, where to employ saturation patrols, existing laws on cell phone use, and marijuana legislation. Although previous studies have been developed to investigate the effects of misreporting crash data on crash prediction models, most existing studies rely on simulated data, which can be difficult to validate in real-world situations.
Under BTSCRP Project BTS-20, “Strategies to Address Misreporting of Impaired and Distracted Driving in Motor Vehicle Crashes,” the University of Wisconsin–Madison was asked to (1) develop procedures to assess the existence and extent of underreporting and overreporting impaired and distracted driving in crash data and (2) propose a methodology to improve the reporting of impaired and distracted driving in motor vehicle crashes.
In addition to BTSCRP Research Report 19, Appendix D is available on the National Academies Press website (nationalacademies.org/publications) by searching for BTSCRP Research Report 19: Strategies to Improve Reporting of Impaired and Distracted Driving in Motor Vehicle Crashes.
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CONTENTS
Chapter 1 Background and Objective
2.1 Misreporting Motor Vehicle Crashes
2.2 Methods to Address Misreporting
Chapter 3 Examination and Documentation of Statewide and Jurisdictional Efforts
Chapter 4 Supplemental Data Sources and Linkages
4.1 Linked Hospital and Crash Data
5.4 Text-Mining Model Training
5.5 Model Testing and Result Analysis
5.6 Exploratory Analysis of Misreported Crashes
5.7 Choice Models to Identify Factors for Misreporting
5.8 Text Classification Method Used in Case Studies
6.1 Text Classification Method for Impaired Driving
6.2 Text Classification Method for Distracted Driving
6.3 Linked Hospital Data Method for Alcohol-Impaired Driving
