DOT HS 811 597 March 2012

Pedal Application Errors
DISCLAIMER

This publication is distributed by the U.S. Department of Transportation, National Highway 

Traffic Safety Administration, in the interest of information exchange. The opinions, findings, and 

conclusions expressed in this publication are those of the authors and not necessarily those of the 

Department of Transportation or the National Highway Traffic Safety Administration. The United 

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Suggested APA Format Reference

Lococo, K. H., Staplin, L., Martell, C. A., & Sifrit, K. J. (March 2012). Pedal Application 

Errors. (Report No. DOT HS 811 597). Washington, DC: National Highway 

Traffic Safety Administration.
i

Technical Report Documentation Page

Form DOT F 1700.7 (8-72) Reproduction of completed page authorized

1. Report No.

DOT HS 811 597

2. Government Accession No. 3. Recipient's Catalog No.

1. Title and Subtitle

Pedal Application Errors

5. Report Date 

March 2012

6.Performing Organization Code

7. Author(s)

Kathy H. Lococo,* Loren Staplin,* Carol A. Martell,

† and Kathy J. 

Sifrit‡

8. Performing Organization Report No.

9. Performing Organization Name and Address

 *TransAnalytics, LLC

 336 West Broad Street 

 Quakertown, PA 18951 

 †Highway Safety Research Center, University of North Carolina

 730 Martin Luther King, Jr. Blvd. 

 Chapel Hill, NC 27599-3430 

10. Work Unit No. (TRAIS)

11. Contract or Grant No.

DTNH22-07-D-00049, 

Task Order No. 06 

12. Sponsoring Agency Name and Address

‡

Office of Behavioral Safety Research

National Highway Traffic Safety Administration

U.S. Department of Transportation 

1200 New Jersey Avenue SE. 

Washington, DC 20590

13. Type of Report and Period Covered

Final Report

14. Sponsoring Agency Code

15. Supplementary Notes

Dr. Kathy Sifrit was the NHTSA Task Order Manager on this project.

16. Abstract

This project examined the prevalence of pedal application errors and the driver, vehicle, roadway and/or 

environmental characteristics associated with pedal misapplication crashes based on a literature review, 

analysis of news media reports, a panel of driver rehabilitation specialists, analysis of multiple crash 

databases, and case studies. An analysis of crashes attributed to pedal-related vehicle equipment 

malfunction, rather than to a driver error, was also carried out based on a media scan. 

Available sources provide an estimate of 15 pedal misapplication crashes per month in the United States, 

but there are limits to the reporting and archiving of these events that could result in underestimation. 

Analyses of media reports and a State crash database indicated that the drivers in almost two-thirds of such 

crashes were females. When crash involvement is plotted against driver age a U-shaped function shows 

significant over-involvement by the youngest (age 16 to 20) and oldest (76 and older) drivers. Driver 

inattention and distraction were common contributing factors across age groups. 

Analysis of news reports examined which vehicle types, makes, and models most often experienced stuck 

accelerators and other equipment malfunctions in crashes between 2000 and 2010. Passenger cars were by 

far the most prevalent, and the makes that were most strongly over-represented in relation to their 

proportion of the U.S. fleet were all domestic.

Besides identifying future research needs, recommendations were to educate physicians about medical 

conditions associated with pedal misapplications; refer drivers with lower limb sensory loss to driver 

rehabilitation specialists for evaluation for hand controls; inform the public about how to counteract an 

unintended acceleration; and provide law enforcement with a practical means of recording information 

about drivers in pedal misapplication crashes. 

17. Key Words

Pedal application errors, pedal misapplication, unintended 

acceleration, crash analysis, safety, older drivers, novice 

drivers, driver performance, functional abilities, human 

factors, medical conditions, driver rehabilitation

18. Distribution Statement

This document is available to the public from

the National Technical Information Service 

www.ntis.gov 

19. Security Classif. (of this report)

 Unclassified

20. Security Classif. (of this page)

 Unclassified

21. No. of Pages

132

22. Price
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TABLE OF CONTENTS

EXECUTIVE SUMMARY .............................................................................................................1

INTRODUCTION AND BACKGROUND ....................................................................................4

BACKGROUND AND UNDERSTANDING OF THE PROBLEM..................................4

PROJECT OBJECTIVE ......................................................................................................5

PROJECT SCOPE...............................................................................................................5

METHODS ......................................................................................................................................6

LITERATURE REVIEW ....................................................................................................6

Technical Literature .................................................................................................6

News Media Reports................................................................................................7

DATA MINING...................................................................................................................8

National Motor Vehicle Crash Causation Survey (NMVCCS)...............................8

North Carolina State Crash Database ......................................................................9

DRIVER REHABILITATION SPECIALIST PANEL.....................................................11

CASE STUDIES................................................................................................................13

Case Study Investigation of Drivers Required to Undergo 

Reexamination Following Pedal Misapplication Crashes (Iowa)..........................13

One-on-One Unstructured Conversations With Drivers Involved in Recent 

Pedal Misapplication Crashes (North Carolina) ....................................................13

RESULTS ......................................................................................................................................15

LITERATURE REVIEW ..................................................................................................15

NTSB Investigations..............................................................................................15

Prevalence ..............................................................................................................16

Characteristics of Pedal Misapplication Crashes...................................................16

Rationale for a Human Factors Cause for Unintended Acceleration Events.........17

Driver Age and Sex................................................................................................20

Cognitive Deficits..................................................................................................21

Age Differences in Foot Movement ......................................................................22

Driver Unfamiliarity With the Vehicle ..................................................................22

Pedal Configuration and Vehicle Geometry..........................................................23

Driver Workload ....................................................................................................28

NEWS MEDIA AND DATA MINING ............................................................................29

Data Limitations.....................................................................................................29

Prevalence of Pedal Misapplication Crashes.........................................................30

Driver Age .............................................................................................................32

Driver Sex ..............................................................................................................35

Driver Height .........................................................................................................36
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TABLE OF CONTENTS (Cont’d)

NEWS MEDIA AND DATA MINING (Cont’d)

Driver License Status and Experience at Time of Crash .......................................38

Crash Location.......................................................................................................40

Environmental and Roadway Conditions..............................................................41

Pre-Crash Maneuver ..............................................................................................41

Startle or Panic Responses.....................................................................................43

Driver Inattention and Distraction .........................................................................45

Driver Out of Position............................................................................................47

Driver Unfamiliarity With the Vehicle ..................................................................48

Driver Medical Conditions or Functional Impairments.........................................48

Vehicle Make and Year .........................................................................................52

Injuries and Fatalities.............................................................................................54

Property Damage ...................................................................................................56

DRIVER REHABILITATION SPECIALIST PANEL.....................................................56

Pedal Application Error Definition........................................................................56

Prevalence of Pedal Misapplications.....................................................................57

Characteristics of Drivers Who Make Pedal Application Errors...........................58

Situational Factors That May Contribute to Pedal Misapplications......................62

Pedal Misapplication Location ..............................................................................64

Possible Explanations for Why a Driver Doesn’t Correct a Pedal 

Misapplication........................................................................................................65

Countermeasures....................................................................................................66

CASE STUDIES................................................................................................................69

Case Study Investigation of Drivers Required to Undergo 

Reexamination Following a Pedal Misapplication Crash (Iowa) ..........................69

One-on-One Unstructured Conversations With Drivers Involved in Pedal 

Misapplication Crashes (North Carolina)..............................................................72

MEDIA ANALYSIS OF PEDAL-RELATED VEHICLE EQUIPMENT 

MALFUNCTIONS ............................................................................................................74

Driver Age .............................................................................................................75

Driver Sex ..............................................................................................................77

Vehicle Type..........................................................................................................79

Vehicle Make, Model, and Year............................................................................80

Time of Day ...........................................................................................................84

Crash Location.......................................................................................................84

DISCUSSION AND CONCLUSIONS .........................................................................................86

REFERENCES ..............................................................................................................................93
iii

TABLE OF CONTENTS (Cont’d)

APPENDICES

APPENDIX A: Meeting Agenda and Moderator’s Guide for Driver Rehabilitation 

Specialist Panel ..................................................................................... A-1

APPENDIX B: Body of Letter Sent by North Carolina Governor’s Highway Safety

 Program to Selected Drivers Who Had Pedal Misapplication Crashes 

 in 2008. ...................................................................................................B-1

APPENDIX C: Discussion Guide for One-On-One Unstructured Conversations in 

Case Studies About Pedal Application Errors........................................C-1

APPENDIX D: Supplemental Data from the North Carolina Crash Analysis, Media

Analysis, and NMVCCS Analysis ........................................................ D-1

APPENDIX E: Medical Conditions or Symptoms Listed by the DRSs That Can Cause 

or Describe Proprioception or Sensory Deficits in the Legs..................E-1

APPENDIX F: Cognitive Impairments That May Explain Why Drivers Do Not 

Correct Pedal Application Errors, Once They Are Made. .....................F-1

APPENDIX G: Supporting Tables for Media Analysis of Equipment Malfunction 

Crashes .................................................................................................. G-1
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LIST OF TABLES

Table 1. Age and Sex Associated With Audi 5000 Unintended Accelerations Compared 

to Age and Sex in All Crashes Nationally (from Walter et al., 1988)...................21

Table 2. Comparison of Crash Types for Pedal Misapplication Crashes Versus All Other 

Crashes. (NC State Crash Database, 2004-2008) .................................................31

Table 3. Prevalence of Pedal Misapplication Crashes in the NMVCCS Sample 

2005-2007 (Weighted)...........................................................................................32

Table 4. Proportion of Males to Females by Age Group, for Drivers in Pedal

Misapplication Crashes.(NC State Crash Database, 2004-2008, n=2,393)...........36

Table 5. Driver Height by Sex for Drivers in Pedal Misapplication Crashes Compared 

With NHANES Anthropometric Data Describing Height by Sex of the U.S. 

Population. .............................................................................................................36

Table 6. License Status of Drivers in Pedal Misapplication Crashes (NC Crash 

Database Sample)...................................................................................................39

Table 7. Number and Percentage of Pedal Misapplication Crashes by Location and Driver 

Age Group (Media Analysis, n=656).....................................................................41

Table 8. Pre-Crash Maneuver (NC Crash Database Sample). .............................................42

Table 9. Pre-Crash Maneuver (News Media Sample). ........................................................43

Table 10. Drivers in Startle-Related Pedal Misapplication Crashes, by Startle Type

(NC Crash Database Sample). ...............................................................................44

Table 11. Pedal Misapplication Crashes Associated with Startle, 

By Age Group (NC Crash Database Sample)........................................................44

Table 12. Drivers in Distraction-Related Pedal Misapplication Crashes, by Age Group

(NC Crash Database Sample). ...............................................................................46

Table 13. Make of Vehicles Involved in Pedal Misapplication Crashes in the 

North Carolina Crash Analysis, Media Analysis, and NMVCCS, 

Compared to Vehicle Makes in Operation in the U.S. Fleet. ................................53

Table 14. Injury Status of Vehicle Occupants and Pedestrians in Crashes Involving Pedal 

Misapplications, by Vehicle (NC Crash Database Sample) ..................................55

Table 15. Pedal Misapplication Crashes, by Maximum Known Police Reported Injury for 

Each Crash. (Unweighted and Weighted NMVCCS Data). ..................................56

Table 16. Pedal Misapplication Crashes by Property Damage Estimates (NC Crash 

Database Sample)...................................................................................................57
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LIST OF TABLES (Cont’d)

Table 17. Summary Statistics Describing Driver Age by Reexamination Requirement, 

for Iowa Drivers in Pedal Misapplication Crashes. ...............................................69

Table 18. Reported Condition of Iowa Drivers Involved in Pedal Misapplication Crashes, 

by Reexamination Requirement (Iowa Sample, n=349)........................................70

Table 19. Restriction Type by Reexamination Requirement for Iowa Drivers in Pedal

Misapplication Crashes..........................................................................................71

Table 20. Number and Percentage of Media-Reported Equipment Malfunction Crashes 

by Malfunction Type and Analysis Group.............................................................75

Table 21. Driver Age by Analysis Group. .............................................................................75

Table 22. Driver Sex by Analysis Group, for All Media-Reported Equipment Malfunction 

Crashes...................................................................................................................77

Table 23. Driver Sex by Analysis Group, for Media-Reported Stuck Accelerator 

Malfunctions Only .................................................................................................77

Table 24. Media-Reported Equipment Malfunction Crashes, by Vehicle Type and

Analysis Group. .....................................................................................................79

Table 25. Media-Reported Equipment Malfunction Crashes by Vehicle Make and 

Analysis Group Versus Percentage of Vehicle Makes in Fleet. ............................81

Table 26. Media-Reported Equipment Malfunction Crashes for Stuck Accelerator 

Crashes Only, by Vehicle Make and Analysis Group Versus Percentage of 

Vehicle Makes in Fleet. .........................................................................................82

Table 27. Media-Reported Equipment Malfunction Crashes by Malfunction Type,

Vehicle Type, and Analysis Group........................................................................83

Table 28. Media-Reported Equipment Malfunction Crashes, by Time of Day and 

Analysis Group. .....................................................................................................84

Table 29. Media-Reported Equipment Malfunction Crashes by Location and Analysis 

Group, All Malfunction Types...............................................................................85

Table 30. Media-Reported Equipment Malfunction Crashes by Location and Analysis 

Group, Stuck Accelerator Malfunctions Only. ......................................................85
vi

LIST OF FIGURES

Figure 1. Percentage of Drivers in Pedal Misapplication Crashes Reported by the Media 

(n=683) in 2000-2010 Versus Percentage of Licensed Drivers in the United States

by 5-Year Age Groupings (n=198,741,423). ........................................................33

Figure 2. Percentage of Drivers in Pedal Misapplication Crashes in 2004-2008 Versus

Percentage of Licensed Drivers in North Carolina, by 5-Year Age Groupings 

(n= 6,301,233)........................................................................................................34

Figure 3. Percentage of Crash-Involved Drivers by 5-Year Age Groupings, for Drivers who 

Made Pedal Application Errors (n=2,399) Versus All Drivers in Other Crashes 

(n=2,228,056). (North Carolina State Crash Database, 2004-2008)......................35

Figure 4. Distribution of Drivers in Pedal Misapplication Crashes by Height, Across Sex 

(N=2,141).(North Carolina State Crash Database, 2004-2008).............................37

Figure 5. Distribution of Drivers in Pedal Misapplication Crashes by Height and Sex 

(N=2,141). (North Carolina State Crash Database, 2004-2008)............................37

Figure 6. Age Distribution of Drivers with Reexamination Requirement Versus No

Reexamination Requirement..................................................................................69

Figure 7. Frequency Distribution by Driver Age and Analysis Group. ................................76

Figure 8. Percentage of Drivers in Equipment-Related Crashes Reported by the

Media (n=452) in 2000-2010, by 5-Year Age Groupings and Analysis Group. ...76

Figure 9. Percentage of Drivers in Equipment-Related Crashes Reported by the 

Media (n=207) in 2000-2010, by 5-Year Age Groupings and Analysis Group, 

for Stuck Accelerator Crashes Only. .....................................................................78

Figure 10. Comparison of Media-Reported Equipment Malfunction Crashes (207 Stuck 

Accelerator Malfunctions Only) and Media-Reported Pedal Misapplication 

Crashes (n=683), by Driver Age Group.................................................................78

Figure 11. Comparison of Findings for Age, by Data Set.......................................................89

Figure 12. Comparison of North Carolina Crash Database and Media Analysis Findings

for Prevalence of Pedal Misapplication Crash Involvement by 5-Year Age 

Groupings...............................................................................................................90
vii

LIST OF ACRONYMS AND ABBREVIATIONS

AMA ................................................................................................American Medical Association

BTSI............................................................................................. brake transmission shift interlock

BTW....................................................................................................................... behind the wheel

CDRS...............................................................................Certified Driver Rehabilitation Specialist

DMV ................................................................................................ Department of Motor Vehicles

DOT ...................................................................................................Department of Transportation

DRS.................................................................................................Driver Rehabilitation Specialist

EDR.....................................................................................................................event data recorder

GHSP .....................................................................................Governor’s Highway Safety Program

NHTSA ................................................................National Highway Traffic Safety Administration

NMVCCS.............................................................National Motor Vehicle Crash Causation Survey 

NTSB .................................................................................... National Transportation Safety Board

OT ................................................................................................................Occupational Therapist

PDI........................................................................................................ potentially driver impairing

PVA..................................................................................................................public vehicular area
1

EXECUTIVE SUMMARY

This project examined the prevalence of pedal application errors—specifically, the driver 

error of mistaking the accelerator pedal for the brake pedal—and the driver, vehicle, roadway,

and/or environmental characteristics that are associated with pedal misapplication crashes. 

Researchers first reviewed the technical literature published between 1980 and 2009, then analyzed

news reports about 899 of these crashes in the United States over the past 10 years. The research 

team conducted two crash analyses, one based on 31 crashes in the National Motor Vehicle Crash 

Causation Survey (NMVCCS) between 2005 and 2007, plus 2,411 pedal misapplication crashes 

between 2004 and 2008 contained in the North Carolina State crash database.

A panel of Driver Rehabilitation Specialists (DRSs) provided another perspective. Panelists

drew on their clinical experience to discuss the medical conditions and functional deficits, the 

maneuvers, the locations, and the driving task demands associated with pedal application errors.

Researchers conducted case studies of drivers in pedal misapplication crashes, using data mined 

from the Iowa reexamination database and from one-on-one, unstructured telephone discussions 

with drivers in North Carolina, to seek additional insights about this phenomenon. 

Finally, in a complementary task researchers completed a media scan for crashes attributed 

to pedal-related vehicle equipment malfunction, rather than to driver error (pedal 

misapplication).Analyses of these reports described the types of vehicles and specific equipment 

problems most often implicated in such crashes, and compared the driver age and sex distributions, 

crash locations, and a range of vehicle characteristics with those describing crashes due to pedal 

application errors.

The literature review identified sparse evidence of the prevalence of pedal application errors.

The studies included were all conducted with driving simulators, so may not reflect real-world

driving behavior. Two predictors for pedal error events were identified, however: increasing driver 

age and impairments in drivers’ “executive function.”1 These studies also demonstrated that pedal 

misapplications could be triggered by sudden changes in the environment that startle drivers.

Analyses based primarily on the results of the media scan and North Carolina crash database 

analysis provided information about the prevalence of pedal misapplication crashes. The former 

source yielded reports of 7 to 15 crashes per month, somewhere in the United States The latter 

source also provided an estimate of less than 1% of all crashes. But media archiving practices 

dictate that researchers will have access to a diminishing sample (i.e., only the most “newsworthy” 

stories) the older the source of the data; and, State database analyses are limited by the absence of 

any codes on police crash reports to indicate that a crash resulted from a pedal misapplication. Thus, 

there is strong reason to believe that each of these sources produced a significant underestimation of 

how often drivers mistake the accelerator for the brake, and a crash ensues. 

The most consistent finding across data sources was the striking overrepresentation of 

females in pedal misapplication crashes, relative to their involvement in all types of crashes.

 1 Executive function describes a variety of loosely related higher-order cognitive processes like initiation, planning, 

hypothesis generation, cognitive flexibility, decision making, regulation, judgment, feedback utilization, and selfperception that are necessary for effective and contextually appropriate behavior (Daigneault, Joly, & Frigon, 2002).
2

Females were the drivers in nearly two-thirds of the pedal misapplication crashes identified in both 

crash databases and in the media scan. Possible explanations might include greater exposure by 

women where these crashes occur most often (parking lots); a poorer “fit” in their cars due to 

shorter stature, which may increase the likelihood of a pedal application error; or a 

disproportionately high rate of one or more functional deficits that contribute to pedal errors, such 

as neuropathy. Explaining this anomaly may be important as a starting point in designing crash 

countermeasures. 

The pedal application error analysis results for driver age were compelling. When the 

percentage of crash-involved drivers was plotted against 5-year cohorts from 16-to-20 age group to 

the 76+ group, both the North Carolina database and the news media reports demonstrated a marked 

U-shaped relationship. Over-involvement in pedal misapplication crashes was especially 

pronounced among drivers 76 and older in the media. This may reflect the sensational nature of 

such events that increases the chances that the media will report them, often in multiple outlets. The 

NMVCCS analysis results did not mirror this pattern, instead showing relatively even levels of 

crash involvement for young, middle-aged, and older drivers; but this should be interpreted with 

caution as this database excludes crashes in parking lots. 

The single factor that may explain over involvement in pedal misapplication crashes at both 

ends of the driver age distribution is poor executive function. The relevant areas of the brain do not 

fully develop until young adulthood, and have been shown to decline with advanced age. The 

participating Driver Rehabilitation Specialists supported this premise, having observed pedal 

application errors among their clients who perform poorly in clinical tests of executive function.

This was not limited to older drivers—panelists reported that young patients with diagnoses of 

autism and attention-deficit disorder are more prone to these errors, too. 

Across age, the most common contributing factor in pedal misapplication crashes was driver 

inattention, cited in 44% of the North Carolina crashes. Distracted drivers may be more likely to be 

startled by an unexpected event or traffic situation, and in their panic to stop or slow the vehicle,

may press the wrong pedal.

Turning to the news reports of pedal-related vehicle malfunction crashes that were screened 

to exclude behavioral causes, three findings were most pronounced. First, the striking 

overrepresentation of female drivers disappeared in such crashes. Next, for a subset of events of 

particular interest – stuck accelerator crashes – both the youngest and oldest driver age groups again 

appeared to be at greatest risk. Alternately, both of these groups again may be the most newsworthy 

for the reporting of such crashes by the popular media. Third, a detailed analysis of vehicle types, 

makes, and models most often in media reports of equipment malfunction crashes from 2000 to 

2010, showed that passenger cars were by far the most prevalent, and the makes that were most 

strongly over-represented in relation to their proportion of the U.S. fleet were domestic. 

Most of the conclusions to be drawn from this project are tentative, pointing to the need for 

additional research to better understand the reasons for this driver behavior. At the same time, safety 

benefits may confidently be predicted from educating physicians about the conditions that are 

associated with pedal misapplications; physicians referring drivers with sensory loss to driver 

rehabilitation specialists who can evaluate their ability to use hand controls; informing the public 

about shifting into neutral if a vehicle accelerates unexpectedly; and providing law enforcement 
3

with a practical means of recording information about drivers in pedal misapplication crashes, to 

improve the quality of traffic records for future data analyses. 
4

INTRODUCTION AND BACKGROUND

This section describes the rationale behind the project, highlights the objectives, and 

provides the reader with a brief overview of the technical approach. 

BACKGROUND AND UNDERSTANDING OF THE PROBLEM

The driver performance deficits termed “pedal application errors” gained a degree of 

notoriety in the 2003 crash in Santa Monica, California, when an older passenger car driver pressed 

the accelerator instead of the brake, surged into a crowd of shoppers at an outdoor market, and 

killed 10 pedestrians and injured 63 others. A National Transportation Safety Board (NTSB)

investigation of the Santa Monica crash confirmed that the cause of the crash was the driver’s 

inadvertent acceleration when he intended to brake, and his continuing acceleration through the 

market due to his faulty belief that his foot was on the brake as he pumped the accelerator. NTSB 

subsequently performed in-depth investigations of 5 crashes that occurred between 2005 and 2008 

involving heavy vehicles in which 2 people were killed and 71 injured, and concluded that pedal 

misapplication was a factor in all 5 crashes. As indicated by the NTSB (2009), “pedal 

misapplication can occur in heavy vehicles as well as light vehicles; any vehicle operated by a 

driver is susceptible to the loss of control caused by human error.”

The media reports newsworthy incidents across the United States on nearly a daily basis, 

including fatal and injurious crashes; and there is anecdotal evidence that such driver errors 

resulting in property damage may be relatively commonplace. However, caution must be used in 

interpreting media data extracted over a certain time period to explain the prevalence of pedal 

misapplication crashes and the characteristics of the drivers involved, because of competing and 

complementary issues biasing reporting of pedal misapplication crashes.

One difficulty in precisely documenting the frequency of crashes involving pedal 

misapplications is that when these events occur on private property or in a parking lot, they may not 

be reported to the police or be registered as entries in any crash database. In order to identify events 

captured in police narratives in a crash database, analysts must distinguish narratives that include 

“pedal” as an element from other crash types with “pedal” as a root term (e.g., pedalcyclist), filter 

for terms such as “mistake” or “slip,” and then critically review the crash narrative to confirm an 

event of interest. At this time, no State uses a code to identify crashes associated with pedal 

application errors.

Ambiguity in the data describing such events also results from a marked inconsistency in the 

use of the expression “pedal errors.” This expression covers a wide range of behaviors, some related 

to mechanical issues and others to driver behaviors. Within the latter category, physical as well as 

cognitive impairments could lead to an unintended acceleration, as could inattention and distraction.

Events related to a “set-shift” (i.e., the driver believes he/she is pressing the brake, and when the 

vehicle accelerates instead of slowing, presses harder) must be distinguished from errors committed 

when multitasking (an information processing limitation). Similarly, “pedal confusion” may refer to 

a state of either generalized or episodic confusion. The former would apply to a person who has 

difficulty using the key or operating the vehicle controls; while the latter might apply to someone 

who is only temporarily confused, e.g., by a distracting noise or thought. Throughout this report, the 
5

terms “pedal application errors,” “pedal misapplications,” and “pedal misapplication crashes” will 

be used to identify the driver behavior of mistaking the accelerator for the brake pedal.

PROJECT OBJECTIVE

The overall objective of this project was to determine the magnitude of the problem of 

crashes associated with pedal misapplications. Specific goals included learning how frequently 

crashes occur as the result of pedal misapplication; whether particular driver groups such as novices 

or older drivers are overrepresented in such crashes; if certain conditions place drivers at higher risk 

of pedal misapplication; and the extent of property damage, injuries, and fatalities caused by these 

errors. 

PROJECT SCOPE

Major tasks in this project included: 

• A literature review, encompassing searches in the technical peer-reviewed literature as well 

as in the news media over the past 10-year period. An additional news media search focused 

on the characteristics of crashes involving brake or accelerator pedal malfunction, for 

comparison with crashes resulting from pedal misapplication. 

• An expert panel meeting with 15 Driver Rehabilitation Specialists (DRSs), to gather 

information regarding their experience with their clients’ pedal application errors.

Specifically, panelists provided descriptions of incidents of clients’ pedal misapplications; 

driving tasks during which these errors seem most likely to occur; characteristics of drivers 

most likely to make such errors; and any additional insights regarding pedal application 

errors.

• Data mining using the National Motor Vehicle Crash Causation Survey (NMVCCS) 

database and North Carolina’s State crash database.

• Case studies of drivers involved in pedal misapplication crashes in Iowa and North Carolina. 

Data mining in the Iowa driver reexamination database provided information about the 

fitness to drive of those involved in such crashes, through their performance on the DMV 

reexamination tests and resulting license actions. Telephone discussions with crash-involved 

North Carolina drivers provided information about the driver, vehicle, and situational factors 

underlying pedal application errors, beyond what might be recorded on crash report forms.
6

METHODS

LITERATURE REVIEW

This literature review encompassed searches in two domains to determine the magnitude of 

crashes associated with pedal misapplications, and the driver characteristics and environmental 

circumstances surrounding these crashes. The peer-reviewed literature included studies describing 

the frequency, severity, and conditions associated with pedal application errors. Because NHTSA 

anticipated that little research had been done in this area, the literature review was extended to 

include reviews of news media reports of crashes related to pedal application errors that have 

occurred within the United States between January 1, 2000, and February 16, 2010. A second media 

search examined driver and vehicle characteristics in crashes involving malfunctions of the braking 

and acceleration systems, for comparison with crashes involving pedal misapplication (driver error).

The search methods used to identify peer-reviewed literature and news media reports are described 

below. 

Technical Literature

Researchers performed searches in the ScienceDirect, TRIS, PsycInfo and Dissertation 

Abstracts databases for literature published between 1980 and 2009, . Since the focus of this project 

was behavioral errors that lead to these crashes—the driver mistakenly pressing the accelerator, 

believing it is the brake pedal—literature relating to equipment failure was methodically excluded 

from the review.

Researchers identified and acquired one report in the ScienceDirect database related 

specifically to pedal misapplication, using the following keywords: braking; rear-end crash; stop/go 

decision; brake response time; brake-perception reaction time; pedal confusion; emergency braking; 

collision warning; time to collision; time to contact; active accelerator pedal; brake reaction time; 

car following; braking time; reaction time; event uncertainty; and driver reaction times.

The TRIS database provided six relevant reports under the following keywords: driver 

errors; pedal errors; automotive foot pedals; pedal configuration; brake pedal; unintended 

acceleration; sudden acceleration incidents; and pedal misapplication.

In the PsycInfo and Dissertation Abstracts databases, researchers identified and acquired 

four reports using the following keywords: pedal errors; braking task; braking response; pedal 

hitting errors; pedal actuation errors; design of pedal & floor & seating geometries in automobiles; 

frequency of accelerator & brake pedal actuation errors during simulated driving; unintended 

acceleration; and foot placement in driving simulator.

A series of structured Internet searches using keywords along with the names of authors of 

key reports identified from the three databases identified four relevant reports not identified in the 

previous searches; these were retrieved for review.

The Internet searches revealed the National Transportation Safety Board (NTSB) as a major 

source of investigative research on this subject. As reflected in past, recent, and ongoing 
7

investigations of pedal application error incidents, especially those involving heavy vehicles and 

commercial vehicles, the NTSB appears to be the most comprehensive United States-based source 

of research on crashes in which drivers applied the gas pedal, thinking they were applying the brake 

pedal. Pedal misapplication is the current NTSB terminology for this type of incident.

News Media Reports

The literature review encompassed reviews of news media reports of crashes related to pedal 

application errors that occurred within the United States between January 2000 and February 2010.

Researchers tracked and archived media coverage using primarily the following Web-based 

tracking databases and tools:

• Google News: Google News is a computer-generated news site that aggregates headlines 

from news sources worldwide. Specifically, media coverage was tracked using the general 

search for more recent articles and the news archive search, which provides an easy way to 

search and explore historical archives.

• LexisNexis News: LexisNexis focuses on the needs of professionals. The University of 

North Carolina at Chapel Hill provided access to archived articles using the News segment 

of LexisNexis. This database provides full-text access to general, regional, and international 

news. 

• America’s Newspapers: The University of North Carolina at Chapel Hill provided access to 

America's Newspapers, a comprehensive U.S. newspaper resource that is updated daily. It 

includes electronic editions of 827 newspapers—with 75% of these sources not available in 

any other library database.

The project team searched and compiled media “hits” between January 2000 and February 

2010 using these databases and the following key phrases.

(Crash OR accident) AND - -

- - Pressed the accelerator instead of the brake

- - Pressed the gas pedal instead of the brake

- - Stepped on the accelerator instead of the brake

- - Stepped on the gas pedal instead of the brake

- - Confused the accelerator for the brake

- - Confused the gas pedal for the brake

- - Confused gas and brake pedal

- - Hit the accelerator by accident (OR mistake)

- - Hit the gas pedal by accident (OR mistake)

- - Mistook the accelerator for the brake

- - Mistook the gas pedal for the brake 

- - Hit the wrong pedal

A second search for reports of crashes involving equipment malfunction (brake or 

accelerator) during the same period used the following terms.

(Crash OR accident) AND - -
8

- - Stuck accelerator (OR gas pedal OR throttle)

- - Jammed accelerator (OR gas pedal OR throttle)

- - Brakes failed (OR failure)

- - Could not stop car (OR vehicle)

- - Sudden acceleration

- - Unwanted acceleration

- - Runaway car (OR vehicle)

- - Floor mat stuck

Any hits that indicated the crash might have resulted from a pedal misapplication were excluded 

from this analysis.

DATA MINING

A national crash database (NMVCCS) and a State crash database (North Carolina) provided

detailed information about crashes involving pedal misapplications, as well as insight into the 

frequency, characteristics, and consequences of these driver errors.

National Motor Vehicle Crash Causation Survey (NMVCCS)

NHTSA’s National Motor Vehicle Crash Causation Survey is a nationally representative 

sample of 5,470 crashes that occurred between January 1, 2005, and December 31, 2007 (NHTSA, 

2008, July). This sample is limited because of NHTSA’s strict guidelines for a crash to qualify for 

an on-scene investigation and inclusion into the database. Specifically,

• The crash must have occurred between 6 a.m. and midnight.

• The crash must have resulted in a harmful event associated with a vehicle in transport on a 

trafficway.

2

• EMS must have been dispatched to the crash scene. 

• At least one of the first three crash-involved vehicles must be present at the crash scene 

when the NMVCCS researcher arrives. 

• The police must be present at the scene of the crash when the NMVCCS researcher arrives. 

• At least one of the first three vehicles involved in the crash must be a light passenger vehicle 

that was towed or will be towed due to damage. 

• A completed police crash report for this crash must be available.

For qualifying crashes, NMVCCS researchers obtained information from all possible 

sources: the crash scene, police, drivers, passengers, witnesses, and vehicles. NMVCCS data

contains information collected on-scene about the events and associated driver, roadway, 

environment, and vehicle factors leading up to crashes involving light vehicles. The survey provides 

in-depth information about the causal chain of a crash: movement prior to the critical crash 

envelope, the critical pre-crash event, and the critical reason for the critical pre-crash event. The 

 2 This criterion results in the exclusion of pedal misapplication crashes occurring in parking lots. 
9

critical reason can be attributed to the driver (distraction, drowsiness, driving too fast, panic), the 

vehicle (tire/wheels, brakes), roadway, or atmospheric conditions (rain, snow, glare).

NMVCCS used a multistage probability sample design to generate a nationally 

representative sample of crashes. Each of the 5,470 crashes has been assigned a weight based on the 

probability of selecting the crash for analysis. The NMVCCS data set contains information about 

1,479 additional crashes that are not weighted because they were investigated during the phase-in 

period (first 6 months of data collection). The data for the 5,470 crashes may be used to determine 

national estimates, but the NMVCCS manual (Bellis & Page, 2008) states that the 1,479 crashes 

assigned zero weights should only be used for clinical study and not for determining national 

estimates.

There is no “pedal application error” field in the NMVCCS data that can be directly queried 

to provide information on crashes that resulted from pedal misapplications. However, one of the 

fields contains a narrative description of the crash. Researchers queried this field to identify crashes 

that may have been caused by the driver pressing the wrong pedal. The query identified crashes 

with narratives containing the words “instead” OR “mistak” OR “inadver,” as well as any of the 

following words: “pedal” OR “peddle” OR “brak” OR “gas” OR “accel.” The query identified 110 

potentially relevant crash narratives.

The research team reviewed each crash narrative to determine whether the crash actually 

resulted from a pedal application error. Of the 110 crashes, 31 were caused by the driver applying 

the wrong pedal (pedal misapplication) and 2 were the result of the driver’s foot slipping from the 

brake and pressing the accelerator (“slips”). The remaining 77 crashes contained the words 

“instead,” “mistake,” or “inadvertent,” but they did not relate to a pedal application error, and were 

therefore excluded from the analysis. For the 31 pedal misapplication crashes, researchers identified 

the vehicle number associated with the driver who committed each pedal application error. The 

NMVCCS case number and vehicle number allowed researchers to extract data about the crash for 

analysis.

North Carolina State Crash Database

North Carolina’s crash database was selected because the crash narrative is included as a 

field in the crash relational database. The field can be searched using inclusive and exclusive terms 

to identify crashes resulting from pedal application errors, making it possible to easily extract all the 

attributes for the selected crashes. In addition, this State database contains crashes that occur in 

parking lots as well as those that occur on-road.

Law enforcement officers use the Crash Report Form DMV-349 to report motor

vehicle crashes in North Carolina. A reportable motor vehicle traffic crash must meet at least one of 

the following criteria (NCDOT, 2006):

• The crash resulted in a fatality, or

• The crash resulted in a non-fatal personal injury, or

• The crash resulted in total property damage amounting to $1,000 or more, or

• The crash resulted in property damage of any amount to a vehicle seized.
10

In addition, a reportable motor vehicle traffic crash must occur on a trafficway (any land 

open to the public as a matter of right or custom for moving persons or property from one place to 

another) or occur after the motor vehicle runs off the roadway but before events are stabilized.

Crashes in parking lots are reportable, if they meet the criteria, and are included in the set of crash 

locations defined as public vehicular areas (PVA). A PVA includes any area that is generally open 

to and used by the public for vehicular traffic, including by way of illustration and not limitation 

any drive, driveway, road, roadway, street, alley, or parking lot upon the grounds and premises of:

a. Any public or private hospital, college, university, school, orphanage, church, 

or any of the institutions, parks or other facilities maintained and supported 

by the state of North Carolina or any of its subdivisions;

b. Any service station, drive-in theater, supermarket, store, restaurant, or office 

building, or any other business, residential, or municipal establishment 

providing parking space for customers, patrons, or the public;

GLOSSARY

c. Any property owned by the United States and subject to the jurisdiction of 

the State of North Carolina. 

Beach areas used by the public for vehicular traffic as well as any roads opened to 

vehicular traffic within or leading to a subdivision for use by subdivision residents, their 

guests, and members of the public, whether or not the subdivision roads have been offered 

for dedication to the public, are also considered as PVAs. The term “public vehicular area” 

excludes any private property not generally open to and used by the public. A PVA crash 

report should contain the same information as if the crash occurred on a roadway.

Some law enforcement officers choose to report crashes that do not meet the State’s 

criteria for a reportable crash. When this occurs, they check the “non-reportable” block on 

the crash report form. 

As with the NMVCCS data recording forms, the North Carolina DMV-349 does not contain 

a code box or data element field to indicate when a crash occurred because a driver made a pedal 

application error. Consequently, there is no “pedal misapplication” field in the North Carolina crash 

data that can be readily queried to provide information on crashes that resulted from a driver 

mistakenly pressing the accelerator, thinking that it is the brake. However, one of the fields contains 

a narrative description of the crash, which we queried to identify crashes that may have been caused 

by the driver pressing the wrong pedal. The query identified crashes with narratives containing the 

text strings “instead” OR “mistak” OR “inadver,” in combination with any one of the following text 

strings: “pedal” OR “peddle” OR “brak” OR “gas” OR “accel.” The query identified 2,930 crashes

for the 5-year period 2004-2008.

Researchers reviewed each crash narrative to determine whether the crash actually resulted 

from a pedal application error. Of the 2,930 crashes, 2,411 were caused by a driver applying the 

accelerator when he or she intended to apply the brake. Fifty-eight were the result of the driver’s 

foot slipping from the brake and pressing the accelerator, 47 were the result of the driver pressing 

the wrong pedal in a vehicle with manual transmission (either clutch or accelerator rather than the 

brake, or the brake rather than the clutch). Reviewers determined the remaining 414 crashes not to 
11

be the result of a pedal misapplication; these 519 incidents were therefore excluded from the present

analyses. 

For the 2,411 crashes resulting from pedal application errors, researchers used the crash case 

number and vehicle number to extract data about the driver and the crash for analysis. No crash had 

more than one driver who made a pedal application error; there was a one-to-one correspondence 

between drivers and crashes.

DRIVER REHABILITATION SPECIALIST PANEL

The DRS panel supplemented information from the news media accounts and police reports.

Panelists provided first-hand accounts of their clients’ pedal application errors, including:

• Descriptions of incidents where clients pressed the gas instead of the brake;

• Driving tasks during which these errors seemed most likely to occur;

• Characteristics of drivers most likely to make such errors;

• Strategies to prevent or reduce pedal misapplication errors;

• Further study methods to learn more about pedal misapplications; and

• Additional insights regarding pedal application errors.

The research team selected the panelists through consultation with the NHTSA TOM, and 

two individuals nationally recognized in this field: Elin Schold-Davis (OTR/L, CDRS) and Susan 

Pierce (OTR/L, CDRS, SCDM). Fifteen of the 16 panelists were DRSs, while 1 panelist was a 

human factors researcher with expertise in sudden acceleration issues who has published several 

papers on the topic. Of the 15 DRSs, 14 were “on-road veterans” with decades of experience sitting 

in the front seat evaluating a broad range of drivers. The clients included those learning to use left 

foot accelerators and hand controls, those with early-stage dementia, those recovering from 

traumatic brain injury and stroke, younger drivers with attention deficit disorder, and medically 

impaired drivers referred by their State DMV for an evaluation of fitness to drive. The 15th DRS 

panelist was a neuropsychologist who performs clinical evaluations and training on a simulator, but 

does not evaluate or train clients on-road (behind the wheel). The panelists are listed below in 

alphabetical order.

• Leah Belle, CDRS, Driver Rehabilitation Coordinator, Roger C. Peace Rehabilitation 

Hospital, OT Dept., Greenville, SC.

• Carol Blackburn, OTR/L, CDRS, Adaptive Mobility Services, Inc., Orlando, FL.

• Cyndee Crompton, MS, ORT/L, SCDCM, CDRS, Driver Rehabilitation Services, 

McLeansville, NC.

• Glenn Digman, OTR/L, CDRS, Coordinator, Driver Training Program, National Rehab 

Hospital, Washington, DC.

• Rosamond Gianutsos, Ph.D., CDRS, FAAO, Cognitive and Driver Rehab Services, 

Sunnyside, NY.
12

• Anne Hegberg, MS, OTR/L, CDRS, Driver Rehab Program, Marianjoy Rehabilitation 

Hospital, Wheaton, IL.

• Tom Kalina, MS, OTR, CDRS, Bryn Mawr Rehab Hospital, Malvern, PA.

• John (Jerry) Kenny, OTR, CDRS, Health South Rehab Center of Toms River, NJ.

• Desiree Lanford, MOT, OTR/L, CDRS, University of Florida Public Health and Health 

Professions, Department of Occupational Therapy, Institute for Mobility, Activity, and 

Participation (I-MAP).

• Miriam Monahan, MS, OTR, Driver Rehabilitation Program, Fletcher Allen Health Care, 

Colchester, VT.

• Susan Pierce, OTR/L, CDRS, SCDM, Adaptive Mobility Services, Inc., Orlando, FL.

• Richard Schmidt, Ph.D., Human Performance Research, Marina del Rey, CA.

• Elin Schold-Davis, OTR/L, CDRS, AOTA Older Driver Initiative, Sister Kenny 

Rehabilitation Institute, Minneapolis, MN.

• Michael Shipp, M.Ed., CDRS, Louisiana Tech University, Ruston, LA.

• Donna Stressel, OTR/L, CDI, CDRS, Sunnyview Rehab Hospital, Schenectady, NY.

• Carol Wheatley, OTR/L, CDRS, Good Samaritan Hospital, Baltimore, MD.

The research team provided the panelists with the Literature Review presenting the state of 

the knowledge on this topic four weeks in advance, and asked that they become familiar with its 

contents by the meeting date. The 1.5-day meeting was conducted on August 19 and 20, 2010, at a 

hotel/conference facility in Washington, DC. The meeting agenda and Moderator’s Guide are

presented in Appendix A. The meeting was (audio) recorded and transcribed by a professional 

transcription service.
13

CASE STUDIES

The purpose of the case studies was to gather detailed information from and about drivers 

involved in pedal misapplication crashes to fill in the gaps left by the data mining activities and 

DRS panel meeting conducted in earlier tasks. Researchers sought information about medical 

conditions and medications; functional ability; use of cruise control prior to the crash; whether 

drivers use both feet to control the pedals; driver height; use of adaptive equipment; driver 

positioning in the driver’s seat; and any driver distractions at the time of the crash. Researchers

collected two types of case study data: detailed data mining in a State license reexamination 

database, and unstructured one-on-one telephone discussions with drivers involved in recent pedal 

misapplication crashes.

Case Study Investigation of Drivers Required to Undergo Reexamination Following a Pedal 

Misapplication Crash (Iowa)

TraCS (traffic and criminal software) data provided by the Iowa DMV to UNC/HSRC for 

the time period 4/15/2007 to 10/4/2010 identified 414 drivers with pedal misapplication crashes.

These data were obtained through a privacy act agreement executed between Iowa DOT and 

UNC/HSRC. Licensing data were available for 349 of these drivers; the remaining 65 were either 

unlicensed, or were out-of-State drivers. Research and Driver Safety Analysis staff in the Iowa 

DOT Office of Driver Services input the license numbers of the 349 drivers into the Iowa Driver 

Re-examination Database, and identified 95 drivers who had undergone reexamination. The 

reexamination path was not the same for all drivers under review. Some drivers were required to 

have an examination by their physician and submit an acceptable medical report in addition to 

passing the DMV tests (road, written, and, vision) while others were required only to pass the DMV 

tests. While the team had planned to obtain data describing medical conditions, medications, and 

adaptive equipment that may have been used by the crash-involved drivers who underwent 

reexamination, privacy and confidentiality issues precluded the DMV’s ability to provide such 

information, even though the data were de-identified. The DMV was able to provide us with the 

following data: driver age and sex; reexamination requirements (medical report, vision test, written 

test, and road test); whether drivers were suspended because they had unacceptable medical reports 

or failed any of the DMV tests; driver condition (as coded by law enforcement on the crash report); 

and the license restrictions that were in force at the time of the crash and following the 

reexamination. The reexamination data were provided to UNC/HSRC, who de-identified the data, 

and provided a file to the TransAnalytics Project PI for analysis.

One-on-One Unstructured Conversations with Drivers Involved in Recent Pedal 

Misapplication Crashes (North Carolina)

Data mining in the North Carolina State crash database identified 508 drivers who had a 

pedal misapplication crash in 2008 (the most recent year for which crash data were available for this 

study). For this set of 508 drivers, the data previously extracted by UNC/HSRC for analysis 

included crash database case numbers and driver age, but no other personally identifying 

information (i.e., no driver license numbers, names, or addresses). North Carolina Department of 

Transportation statute prohibits sharing of personally identifying data to entities outside of the 

DOT. However, the North Carolina Governor’s Highway Safety Program (GHSP) and the North 

Carolina Department of Motor Vehicles (DMV) are both part of the North Carolina DOT, and the
14

DOT statute allows for this information to be shared between the DMV and the GHSP. The GHSP 

agreed to mail letters to drivers asking the recipients to call the TransAnalytics PI on a toll-free 

number to participate in an anonymous phone conversation. UNC/HSRC extracted the names and 

addresses of a subset of the drivers involved in pedal misapplication crashes from the North 

Carolina State database, and provided this information to the GHSP.

The target sample size for the Case Study was 100 drivers. The research team selected a

subset of 226 drivers for the GHSP solicitation to participate in the telephone conversations by 

eliminating drivers who were unlicensed or had out-of-state licenses, sorting the remaining drivers 

by age, and choosing every other driver. Appendix B contains the solicitations letter which states 

that (1) participation is voluntary—drivers’ license status would not be affected whether they 

participate or not—and (2) TransAnalytics would not ask drivers for their names or license 

numbers, so their responses would remain anonymous. Since the participants remained anonymous, 

it was not possible to link their responses to their crash data extracted during the earlier data mining 

task in this project.

When the drivers called TransAnalytics’ toll-free number, they were asked to describe as 

much as they could remember about the crash, and to self-report medical conditions and 

medications, describe how they use their pedals, and the kind of shoes they were wearing when they 

crashed. The guide for the unstructured discussions is presented in Appendix C.
15

RESULTS

LITERATURE REVIEW

The findings from the technical, peer-reviewed literature are summarized in this section. The 

findings from the media review of pedal misapplication crashes are integrated with the findings 

from the data mining tasks to facilitate comparisons of specific characteristics across data sources.

NTSB Investigations

The NTSB investigated seven crashes involving both light and heavy vehicles to identify 

patterns and driver causes of crashes involving pedal misapplications (NTSB, 1998; 2004; 2009).

NTSB crash investigations provide detailed information about drivers’ medical factors, driving 

experience, vehicle factors, and environmental factors. These data, obtained through interviews with 

the drivers and witnesses, medical reports, toxicology tests, and mechanical inspections of the 

crash-involved vehicles, can provide rich information about the causes of crashes. The 

investigations involved a transit bus driver (Normandy, Missouri, 1997); a passenger vehicle driver

(Santa Monica, California, 2003); a fire truck driver (Asbury Park, New Jersey, 2006) and four

school bus drivers (Liberty, Missouri, 2005; Falls Township, Pennsylvania, 2007; Newtown, 

Pennsylvania, 2008; and Nanuet, New York, 2007).

In all seven crashes, the drivers either reported a loss of braking or were observed by vehicle 

occupants or witnesses to be unsuccessfully attempting to stop the vehicles; however, investigators 

found no evidence of braking system failure. The NTSB determined that pedal misapplication was a 

factor in all seven crashes.

As a result of their investigation of the Falls Township, Newtown, and Asbury Park crashes, 

all of which began from a parked position, the NTSB recommended that NHTSA require the 

installation of brake transmission shift interlock (BTSI) systems or equivalent technology in newly 

manufactured heavy vehicles with automatic transmissions and other transmissions susceptible to 

unintended acceleration associated with pedal misapplication when starting from a parked position 

(NTSB, 2009). A BTSI is a technology that forces drivers to have their foot on the brake when 

shifting out of park, in any key position. A BTSI would not have prevented the Liberty, Nanuet, and 

Santa Monica crashes, because the vehicles were in motion when the pedal misapplications 

occurred. Congress required all light vehicles to be equipped with BTSI by September 1, 2010

(Section 2(d) of Public Law 110-189; see FMVSS 114, Final Rule, March 2010); however, there is 

no requirement for heavy vehicles.

The NTSB used driver and witness statements to determine that the Santa Monica crash was 

caused by unintended acceleration, initiated by pedal misapplication. The board concluded that the 

presence of an event data recorder (EDR) in the vehicle would have provided data needed to assess

and understand the driver’s acceleration, steering, and braking behavior, and its contribution to the 

crash. As a result of their investigation, the NTSB recommended to NHTSA that once standards for 

EDRs are developed, their installation should be required in all newly manufactured light-duty 

vehicles (NTSB, 2004). In August 2006, NHTSA published a final rule (71 FR 51043) that 

standardized the information EDRs collect and addressed the survivability requirements for EDRs 

(United States Code of Federal Regulations, Title 49, Part 563). However, this rule does not require 
16

vehicles to be equipped with EDRs. The rule only establishes standards for EDRs that 

manufacturers choose to install. The standards apply to vehicles manufactured on or after 

September 1, 2010 including passenger cars, multipurpose passenger vehicles, trucks, or buses with 

a GVWR of 8,500 pounds or less. In the proposed rule, NHTSA predicted that 65% to 90% of new 

vehicles would be equipped with EDRs.

As a result of the NTSB investigations of pedal misapplication in heavy vehicles, the Board 

reiterated and reclassified a 1999 recommendation to NHTSA to require that all school buses and 

motorcoaches manufactured after January 1, 2003, be equipped with on-board recording systems 

that record multiple vehicle parameters, among which are braking input (NTSB, 2009). The Board 

stated that if these vehicles had been equipped with EDR, the question of the drivers’ actions during 

specific events could be documented, and investigators would have a physical record of specific 

actions and control inputs.

Prevalence

Using a driving simulator, Rogers and Weirwille (1988) found that serious pedal errors 

(defined in their study as pressing the wrong pedal or both pedals simultaneously) occurred at a rate 

of 1 per 4.8 hours of data collection, or 1 per 468 foot movements. They observed a total of 7,008 

foot movements resulting in 297 errors during the 72 hours in which data were collected. Of the 

297 errors, 15 were serious (i.e., the subject mistook the accelerator for brake, the brake for the 

accelerator, or pressed both pedals). There were only two incidents where the subject pressed the 

accelerator instead of the brake. In both cases, the subject recognized and corrected the error 

immediately (i.e., there were no instances in which the subject persisted in mistaking the accelerator 

for the brake). The other errors occurred when the driver’s foot caught or scuffed a pedal during 

foot movement. The authors concluded that serious pedal errors occur rarely.

Characteristics of Pedal Misapplication Crashes

Schmidt, Young, Ayres, and Wong (1997) used keywords to search police narratives 

contained in the North Carolina crash database for pedal error crashes that occurred from 1979 to

1980. They identified 219 crashes for analysis, including pedal application errors and foot slips, 

where the drivers stated that their foot contacted the accelerator rather than the brake. All these 

crashes occurred after the driving cycle had begun rather than at the beginning of a driving cycle 

when a driver shifted from “Park” to “Reverse” or “Drive.” The authors indicate this may be the 

result of brake transmission shift interlocks installed on vehicles to prevent this type of pedal 

misapplication.

The study classified crashes as occurring either during parking or driving on the road. Of the 

219 crashes, only 23 (10.5%) occurred during a parking maneuver. Of these, 14 (61%) occurred 

while the driver was moving forward, and 9 (39%) when the driver was moving in reverse. Of these 

23 parking lot pedal misapplication crashes, 8 occurred because the driver’s foot slipped from the 

brake to the accelerator (none because the foot was slippery or wet) and 15 occurred because the 

driver hit the wrong pedal. Parking lot crashes were further classified according to whether the 

scenario was hurried or unhurried based on temporal urgency, as stated in the crash narratives. Of 

the 19 crashes that could be classified based on the information in the police report, 18 (95%) were 

unhurried – the driver was not responding to an urgent event.
17

The majority of the pedal error crashes occurred during driving (196 of 219, or 89%). Of 

these, 111 (57%) were caused by a foot slip, and 85 (43%) because the driver pressed the wrong 

pedal. Of the 171 crashes where the scenario could be classified, 117 were unhurried (68%) 

compared to 54 hurried (32%). The driving circumstances surrounding the pedal error crashes could 

be classified in 154 of the crashes that occurred during driving (includes slips and wrong pedal 

instances) as follows: slowing normally (36%); turning (22%); the vehicle was stopped (18%); the 

driver was distracted (10%); the vehicle was hit by another object (8%); the driver was avoiding an 

obstacle (6%). In nearly all the crashes that occurred because a driver was avoiding another object 

or the vehicle was stopped, the cause of the pedal error was a foot slip. In crashes that occurred 

when the driver was slowing, 76% occurred because of a foot slip and 24% occurred because the 

driver hit the wrong pedal. All the crashes that occurred when a driver was hit by another object 

occurred because the driver hit the wrong pedal. In the crashes that occurred during a turning 

maneuver, the majority (82%) occurred because the driver hit the wrong pedal and 18% were 

caused by a foot slip. 

These findings highlight the fact that pedal application errors may occur more often during 

the driving cycle than at initial start up, as earlier believed, and may commonly occur under 

unhurried conditions. Although brake-shift interlocks appear to have been successful in preventing 

pedal misapplication crashes at the beginning of a driving cycle, they cannot prevent a pedal 

misapplication crash when the error occurs during the driving cycle. Schmidt et al. (1997) found 

that pedal errors involving a driver hitting the wrong pedal most often occurred during turning 

maneuvers and when a driver was presumably startled after hitting (or being hit by) another object.

Rationale for a Human Factors Cause for Unintended Acceleration Events

Schmidt (1989) reviewed the research on movement control from a human factors 

perspective to examine the relationship between foot placement errors and unintended acceleration, 

with a specific focus on the following questions: 

(1) What is the source of foot placement errors, especially for experienced drivers?

(2) Why would a driver not perceive this error immediately?

(3) Why would the driver persist in pressing the wrong pedal for a sufficient time that a crash 

could occur, in some cases, for as long as 12 seconds?

Driver Errors in Foot Placement. As noted by Brackett, Pezoldt, Sherrod, and Roush (1989), 

movement of the foot from one pedal to another is a “blind positioning movement.” Drivers 

perform this movement without looking at their feet. When controls are not visible to operators, 

they must rely on proprioception and the kinesthetic senses3 that provide the ability to discriminate 

foot position— and the direction, amplitude, and speed of movement — as well as the pressure 

exerted.

A driver may choose a correct response (e.g., decide to step on the brake) but fail to execute 

the response effectively (e.g., step on the accelerator by mistake) for a number of reasons. These 

 3 Proprioception: sense of position of the limbs and trunk (knowing where your body is in space). Kinesthesis: sense of 

movement in the limbs and trunk (the experience of movement in your body through space). (Hermans, 2002). 
18

include variation in the force and timing of muscle movements; head and body position; and 

negative transfer from other vehicles, as described below (Schmidt, 1989).

Variability in producing a foot movement—both the trajectory and endpoint—could result in 

an error in foot placement. Schmidt (1989) states that almost every braking movement results in the 

foot contacting the brake pedal, but there is substantial variation in actual placement, because the 

brake pedal and foot are large and overlap considerably. Variation in movement may be so large that 

the driver misses the brake pedal completely. If the deviation is to the right, then the driver will 

strike the accelerator pedal instead of the brake, fully believing that he/she pressed the brake because 

this was the expectation. The force and timing of muscle movements will affect the variability in 

foot placement. Foot placement errors mainly originate in the driver’s motor system (at functionally 

low levels of the central nervous system) because of force and time variability in the spinal cord 

which causes muscles to contract and produce the actions. The more force used, the greater the 

variability in foot placement, and the faster the movement, the greater the force needed.

With regard to unintended acceleration, the farther the foot is from the intended pedal when 

the driver initiates a movement toward it, the larger the variable errors will be in hitting the pedal 

(due to the greater force). When the driver’s foot is on the accelerator, the movement distance to the 

brake is small, and variable errors should be smaller. But when a driver is initiating a driving cycle, 

the right foot may be in a variety of places prior to shifting from park, all further from the brake than 

if the foot were on the accelerator as in the driving cycle. Therefore, variable errors in aiming should 

be larger at the beginning of a driving cycle than after it has begun. Faster movements to contact the 

brake pedal, are likely to result in increased variation in the movement (due to greater forces). This 

is particularly relevant when the driver makes a hurried braking response.

Another factor that can affect foot aiming accuracy is head and body position. The driver 

may shift position and temporarily bias the direction of foot aim rightward when starting the driving 

cycle (Schmidt, 1989). The result could be a foot movement shifted to the right, enough so that he 

or she strikes the accelerator instead of the brake, leading to unintended acceleration.

Head position can influence a driver’s perception of the spatial position of the (unseen) 

brake pedal. Moving the head or the eyes can cause large systematic biases in the direction of the 

aim of the foot. Movements in head position activate proprioceptive receptors in the neck which 

may in turn, alter the perceived spatial position of the brake pedal with respect to the body, 

influencing limb placement. In studies cited by Schmidt, errors ranged from 5.7 degrees to the left 

when the head was rotated to the right, to 4.6 degrees to the right when the head was moved to the 

left. A driver turning to the left while looking in the left side mirror, or reaching for the seat belt 

when initiating the driving sequence may bias the perceived position of the brake pedal to the right.

This bias could be sufficiently large that the driver could miss the brake and strike the accelerator.
19

Another source of bias toward the right could be introduced by a change in seating position, 

disrupting the driver’s postural set or orientation to the vehicle when driving is resumed. Although 

the disruption is temporary, it can be substantial for a few seconds, producing a large bias in aiming.

Aiming the postural set to the right, could lead to the driver pressing the accelerator rather than the 

brake.

Schmidt and Young (1997) note that drivers using cruise control can shift position. When an 

out-of-position driver tries to slow the vehicle by tapping on the brake to disengage the cruise 

control, the foot may hit the accelerator by mistake. Also, performance decrements may result when 

a driver is monitoring rather than controlling a vehicle (as when using cruise control). This has been 

shown by aircraft pilots who are in a relaxed state using auto-flight controls and then produce 

excessive control inputs with the wrong foot (e.g., full left rudder instead of right rudder) when 

startled by turbulence.

Negative transfer from other vehicles can also contribute to bias errors in foot placement.

Negative transfer is a decrement in the performance of one task as a result of practice or experience 

in another task. For example, if a person drives the same car all the time and then drives a different 

make of vehicle in which the brake pedal is placed relatively more leftward, negative transfer from 

the customary to the new vehicle could reduce the accuracy of pedal movements. Brackett et al. 

(1989) report that the body of research on blind positioning movements (or kinesthetic memory) 

suggests that a person who tries to reproduce learned movement using only kinesthetic memory 

tends to overshoot short distances and undershoot greater distances. Also, accuracy is diminished if 

other movements are made with the same limb prior to reproducing the desired movements.

Error Detection. Schmidt (1989) describes a theory of movement perception called 

“efference copy,” that explains why a driver may not detect that he or she has hit the accelerator, 

rather than the brake as intended. According to this theory, when the central nervous system sends a 

motor signal (to the right leg/foot) to make a movement, a copy of the motor (efferent) command is 

sent to another location in the brain that is primarily sensory in nature. The purpose of the efferent 

copy may be to tell the brain’s sensory system what the brain’s motor system ordered, to prepare it 

for actual feedback from the leg/foot. The efference copy is a reference of correctness against which 

the future movement signals will be compared. To relate this theory to unintended acceleration, 

because the highest central nervous system levels have correctly ordered a movement toward the 

brake pedal, under certain circumstances the efference copy may substitute for actual feedback from 

the leg/foot; this indicates a correct movement (toward the brake pedal) even though the actual 

movement deviates and contacts the accelerator. This would be consistent with a driver “knowing” 

his or her foot was on the brake, when it actually pressed the accelerator.

Selective attention may also come into play to explain why a driver does not detect an error 

in foot placement. Little attention is given to the execution of a foot movement, especially if it is 

fast, predictable, and well practiced. Once a driver has made a foot movement, selective attention 

directs attention to other information sources that are more relevant, such as the traffic scene ahead, 

to plan and make steering movements. When attention is directed to the traffic scene, it is unlikely 

that the driver will attend to feedback from the foot that it is on the wrong pedal. At the same time, 

the driver may have a subjective experience (from efference copy) that the foot is on the brake 

pedal. Depending on the intensity of other stimuli that are holding a driver’s attention at the time of 
20

a pedal application error and the associated depth of processing, a driver may not notice a difference 

in how it feels to depress the accelerator compared to how a brake pedal depression feels.

Correcting Errors. Citing Angel and Higgens (1969) and Schmidt and Gordon (1977), 

Schmidt (1989) states that under laboratory conditions and some practical conditions, people detect 

errors in limb aiming quickly; depending on situational factors, this can be as fast as 120 ms for a 

kinesthetic stimulus or 200 ms for a visual or auditory stimulus. Reaction times to initiate a foot 

movement are approximately 500 ms, plus another 200 ms for the movement of the foot from the 

accelerator to the brake (Schmidt, 1988). However, numerous cases of unintended acceleration have 

lasted as long as 12 seconds. Schmidt (1989) points to three conditions that could extend error 

correction times: hypervigilant reactions (panic), perceptual narrowing, and habitual responses 

under stress. 

Under extreme stress, a panic reaction may occur where a person attends indiscriminately to 

minor and major threats, frantically searching for a way to escape a perceived hazard. This can 

temporarily impair cognitive functioning, resulting in impulsive and often poor and dangerous 

choices. People may freeze, appearing to take no action at all, when they are actually attending to 

multiple cues in rapid succession without being able to make an effective response. This is a 

“hypervigilant” state, characterized by three causes: a strong startling stimulus, perception of the 

stimulus as life threatening, and the sense that a solution must be found immediately. In unintended 

acceleration events, the strong stimulus is the unexpected, violent acceleration, often accompanied 

by loud sounds. The driver may perceive this as life threatening, evoking fear for self, passengers, 

and other drivers and pedestrians. The sense of imminent danger makes it important to find a 

solution fast. Information processing is impaired as the driver is distracted by what is happening in 

the environment; he or she does not identify the solution, i.e., to move the foot to the brake, because 

the driver “knows” the foot is on the brake, so assumes the brakes have failed.

Another effect of stress is perceptual narrowing, or shrinking of the attentional field. The

driver focuses on central events and misses peripheral cues (visually and perceptually), as well as 

potentially effective solutions.

Finally, stress increases the likelihood that a driver, placed under high demand for an 

effective response, will produce a habitual, well-practiced behavior. When a driver who panics with 

his/her foot on the accelerator (believing it to be on the brake), responds with hard “braking” or 

pumping the “brakes,” the result is more acceleration, which generates more stress, and more hard 

“braking.” 

Driver Age and Sex

Walter, Carr, Weinstock, Sussman, and Pollard (1988) found that middle-aged and older 

drivers (and particularly female drivers) involved in Audi 5000 sudden acceleration incidents were 

over-represented compared to drivers in all crashes Nationwide (see Table 1). However, such 

individuals were also overrepresented as owners and drivers of Audi 5000s. Male and female 

drivers over age 50 (defined as older drivers by Walter et al.) accounted for 20.8% (males) and 

24.3% (females) of the sudden acceleration (SA) incidents reported to NHTSA. By comparison

Nationally, older males were involved in 12.2% of all crashes and older females 6.3% (NASS 

database).
21

Nationally, males of all ages accounted for 61% of the crashes and females 33% (where sex 

was reported). In the Audi sudden acceleration crashes, the pattern was reversed, with males 

accounting for 40% and females 57%. Citing data from the Nationwide Personal Transportation 

Study (NPTS), Walter et al. note that female drivers took more trips that required frequent starts and 

stops, which are conditions that increase the opportunity for sudden acceleration incidents, 

specifically, pedal misapplications following an engine surge (unexpected increase in engine power)

associated with the Audi 5000 in the years 1984 to 1986.

Table 1. Age and Sex Associated With Audi 5000 Unintended Accelerations Compared to Age 

and Sex in All Crashes Nationally. (From Walter et al., 1988)

Age Group

Audi 5000 Unintended 

Accelerations

1984-1986

NASS Database 

(All Crashes Nationally)

1984

Male Female Male Female

<30 3.5% 5.3% 30.4% 15.6%

30-49 15.5% 27.8% 18.5% 11.4%

50+ 20.8% 24.3% 12.2% 6.3%

Total 39.9% 57.4% 61.1% 33.4%

Cognitive Deficits

Citing evidence (Pollard and Sussman, 1989) that unintended acceleration crashes are more 

likely to involve older drivers and may result from cognitive deficits, Freund, Colgrove, Petrakos, 

and McLeod (2008) conducted a driving simulator study to determine the extent to which cognitive 

functions contribute to pedal application errors among older drivers. Freund et al. (2008) liberally 

defined unintended acceleration events in their study as an inappropriate acceleration or a failure to 

decelerate, when deceleration or a transition from accelerating to braking was required by a demand 

in the driving situation (e.g., stop sign, vehicular intrusion, pedestrian intrusion). They found that 

drivers with impairments in executive functioning, as measured using the Clock Drawing Test, were 

10 times more likely to experience unintended acceleration events than drivers with normal 

executive functioning. One-third of the drivers experienced unintended acceleration events, 70% of 

whom verbalized their inability to slow or stop the vehicle.

4 The number of unintended acceleration 

events per driver ranged from 1 to 11, and occurred most often in response to a sudden change in 

environment such as changing traffic lights and intrusions into the driving environment. Drivers 84 

or older were 6 times more likely to experience unintended acceleration events.

Freund et al. (2008) conclude that deficits in executive functioning may be an important 

contributor to pedal application errors and unsafe driving, and recommend that practitioners 

consider measures of executive function when evaluating patients for their ability to drive safely.

Executive function is involved in planning and decision-making, error correction and trouble 

shooting; drivers rely on this ability in situations requiring novel responses and sequences of 

 4 The study authors note that the verbalization of an inability to slow or stop the vehicle suggests that the drivers 

recognized that deceleration was required but failed to recognize they made an error in pedal choice. These can be 

interpreted as pedal misapplication unintended acceleration events.
22

actions, situations that are hazardous or technically challenging, and situations necessitating the 

resistance to temptation or requiring a course of action that goes against strong habitual response 

(Norman & Shallice, 1980, cited by Freund et al., 2008). With executive dysfunction, Freund et al. 

(2008) note that the automatized and procedural skills learned over decades of daily driving are 

applied in an inflexible manner and thus do not protect the older driver from making errors.

In their simulator study using interactive computer-video scenarios as measures for 

screening functional aspects of driving performance, Schiff and Oldak (1993) describe a 

“completely unexpected” observation of unintended acceleration by 2 of the 109 study participants 

over age 55. The unintended acceleration events occurred in similar driving situations as those 

reported by Freund et al. (2008) in response to a sudden change in the environment, such as an 

intrusion by another road user. 

Age Differences in Foot Movement

Cantin, Blouin, Simoneau, and Teasdale (2004) showed increased movement variability in 

the right foot behavior of older versus younger subjects. In a driving simulator study conducted by 

these researchers, older drivers’ right foot movement amplitudes were significantly greater than 

those of younger drivers (11.55 versus 10.10 cm, respectively), when moving their right foot from 

the accelerator to the brake to stop at a stop sign or red light. Older drivers also showed significantly 

greater within-subject variability in foot-movement amplitude (1.37 cm for older drivers versus 0.95 

cm for younger drivers). In addition, older drivers made several submovements of the right foot 

following initial release of the accelerator pedal; younger drivers rarely made such submovements.

Submovements were defined as movements greater than 10 cm/s, to differentiate them from small 

wobbling movements. The average number of submovements made by older subjects was 1.94 

compared to 0.44 for younger subjects.

No pedal application errors were observed in the Canton et al. study. While the authors 

observed that older drivers’ right foot movements are more variable that that of younger drivers, 

they noted that more research is needed to determine if there is a direct relationship between 

variability in lower limb movement and pedal misapplications. Canton et al. (2004) noted two 

limitations in their study: the simulated drive required no left turns (due to software limitations), 

and drivers were not distracted by external events or secondary tasks such as talking to passengers.

More complex driving situations, coupled with variable foot movements, may increase the 

likelihood of pedal application errors.

Driver Unfamiliarity with the Vehicle

Researchers have found that drivers in unfamiliar vehicles (e.g., leased vehicles) have a 

higher risk of crashes and near-crashes, and make more evasive maneuvers than when they are 

driving their own vehicles (Lee, Dingus, Klauer, Neale, & Sudweeks, 2005).

5 In this 4-week study 

using the same driver as his/her own control, the higher risk in a leased vehicle persisted into the 

fourth and final week of the study, even when exposure differences were taken into account. 

 5 Pedal application errors were not a focus of this study, and no mention was made of pedal misapplication as a cause of 

the evasive maneuvers. 
23

In related work, Pollard and Sussman (1989) reviewed the NHTSA complaint data for 

vehicles with high reported sudden acceleration incident rates, and found that complaints about 

unwanted engine power fell substantially with increases in vehicle mileage. They attributed this 

drop to a decrease in the likelihood of pedal misapplications as drivers became more familiar with 

their vehicles.

Walter, Carr, Weinstock, Sussman, and Pollard (1988) conducted a study to determine the 

possible contributions of the vehicle and the driver to the high rate of sudden acceleration incident 

complaints for the Audi 5000. Between 1978 and 1986, drivers attributed 556 crashes per 100,000 

Audi vehicles sold in the United States to unintended acceleration. By comparison, the highest rate 

for other vehicles was 28 per 100,000 vehicles. Walter et al. compared the Audi 5000’s interior 

seating and pedal arrangements to hundreds of other vehicle models in the U.S. fleet for critical 

driver-related dimensions. They found significant differences for 20 dimensions, including seat 

height; knee angle; lateral steering wheel position; knee clearance; brake pedal force, size, height, 

and travel; and accelerator pedal size and height. Next, Walter et al. (1988) looked at driver 

experience for the drivers filing a complaint of sudden unintended acceleration for the Audi 5000.

They found that 44% of the drivers had less than 6 months’ experience with the vehicle, and 

according to Audi interviews of drivers involved in sudden acceleration incidents, the majority did 

not own the vehicle or did not drive it regularly. As a means of comparison, an analysis of 

NHTSA’s National Automotive Sampling System (NASS) database indicated that 34% of all 

drivers involved in crashes nationwide had less than 6 months of experience in the vehicle involved.

Walter et al. (1988) concluded that once an unintended acceleration had begun,

6 pedal 

misapplication resulting from panic, confusion, or unfamiliarity with the Audi 5000 contributed to 

the severity of the incident.

Pedal Configuration and Vehicle Geometry

As noted by Pollard and Sussman (1989), a driver must be able to distinguish the brake from 

the accelerator without looking at the pedals. Drivers use sensory cues, which are different for each 

pedal, to make this distinction. The most significant cues are pedal position (a spatial code) and feel 

(amount of force to depress the pedal). The direction and curvature of the motion required to 

operate a pedal are also part of the feel. Drivers may use other spatial reference points such as the 

transmission hump in distinguishing the pedals. Depending on the type of shoes the driver is 

wearing, less useful cues include pedal size, shape, angle, surface texture, and contour. Researchers 

have carried out a number of studies over the past two decades to determine whether the design of 

the brake-accelerator cluster is associated with crashes involving unintended acceleration or pedal 

misapplication.

In a sample of 10 make/model/year vehicles7 with high report rates to NHTSA of sudden 

acceleration, Pollard and Sussman (1989) found the following characteristics that could increase the 

probability of a pedal misapplication: (1) relatively close lateral spacing between brake and 

accelerator; (2) relatively smaller vertical spacing between brake and accelerator, increasing the 

probability of pressing both pedals simultaneously; (3) relatively long brake-pedal travel resulting 

 6 In the Audi 5000, these were due to a failure in the idle-stabilizer system, producing an initial acceleration of 0.3g). 7 Audi 5000 (1983 and 1985), Buick LeSabre (1985), Cadillac Coupe de Ville (1985), Chevrolet Camaro (1984), 

Chrysler New Yorker (1984), Mercedes 300E (1986), Mercury Grand Marquis (1984), Nissan 300ZX (1985), and 

Toyota Cressida (1984).
24

in a “soft feel,” which makes both pedals feel the same, reducing the chances that an error will be 

recognized, and permits engine torque to exceed brake torque when both pedals are pressed 

simultaneously; and (4) a relatively powerful engine, making it more likely a crash will occur 

before a driver has time to make a correction. 

These researchers measured the pedal separation and force deflection in 17 vehicles, some 

that had high “reported sudden acceleration incidents” (RSAI); those with low RSAI rates were 

used as a comparison group. All of the tested vehicles with high RSAI rates moved when the drivers 

applied light to moderate levels of force (less than 50 pounds) with the right foot to both pedals 

simultaneously, by tilting the foot slightly to the right. Under these conditions, the driver reported 

that the sensation was similar to stepping on the brake pedal alone, and that the force to stop the 

vehicle was substantially greater than required for normal stopping. In a wide-open-throttle 

situation, substantial pedal force (at least 175 pounds) was required to achieve maximum 

deceleration for some vehicles tested. Pollard and Sussman cite evidence that 50% of all women 

and a smaller proportion of weaker men cannot provide brake pedal force of more than 175 pounds 

for a period of 1 to 5 seconds. Most of the reported sudden unintended acceleration incidents 

Pollard and Sussman reviewed included driver statements concerning the lack of braking 

effectiveness. The reports frequently indicated that the drivers felt certain they did not press the 

wrong pedal.

In comparison, test drives in the vehicles with low RSAI rates had pedal arrangements that 

made it relatively difficult to exert any substantial force on the accelerator while simultaneously 

pressing the brake with the same foot.

Some vehicles had pedal characteristics that were conducive to pedal misapplications, but 

had low RSAI rates. Pollard and Sussman noted that these vehicles may have other characteristics 

that reduce the consequences of a pedal misapplication. For example, the Honda Civic has low 

engine power and a low noise level.

Walter et al. (1988) found that the Audi accelerator pedal was significantly higher than the 

accelerator pedal in other vehicles (139.0 mm for the Audi in 1983 and 110.0 mm for the Audi in 

1986 versus an average of 71.0 mm for all domestic vehicles). Audi’s brake height, however, was 

similar to other models (168.0 mm in 1983 and 152.0 mm in 1986 versus an average of 147.3 for all 

domestic vehicles).

Although Pollard and Sussman (1989) made recommendations to increase the lateral 

separation of pedals and to raise the brake pedal with respect to the accelerator, they note that these 

changes would not completely eliminate sudden acceleration incidents, as the majority of 

automobiles in use at the time the report was prepared had pedal configurations consistent with their 

recommendations. Also, the test-drive experience indicated that it was not only the static positions 

of the pedals, but also how they moved with respect to each other and how much engine torque and 

brake torque were generated at various displacements that could influence the probability of a pedal 

misapplication.

For the purposes of their study, sudden acceleration was defined as an unintended, 

unexpected, high-power acceleration from a stationary position or a very low initial speed, 

accompanied by an apparent loss of braking; typically when shifting from “Park” to “Drive” or 
25

“Reverse.” Their recommendation to install automatic brake-shift-interlocks to prevent unintended 

acceleration had already been adopted or considered by a number of manufacturers8

.

Pollard and Sussman (1989) concluded that human factors play a large role in sudden 

acceleration problems and that pedal misapplications are the most probable explanation for the 

majority of such incidents when there is no evidence of throttle sticking or cruise control 

malfunction—the only two vehicle component failure modes that could result in the wide-openthrottle condition that is characteristic of a sudden acceleration incident report. Their conclusion 

followed from their study of the fuel systems, braking systems, and driving controls of the 10 

vehicle makes/models/years with high RSAI rates as well as measurements of vehicle behavior 

under simulated fault conditions (on road with the vehicles and bench tests of components).

Although they identified certain malfunctions that could cause the throttle to open or stick, these 

would be readily detectable in a post incident investigation. Cruise control systems are the only 

vehicle component suspected of initiating a wide-open-throttle condition without the driver pressing 

the accelerator. Also, for “recent” factory-installed cruise controls (as of the 1989 report) digital 

circuitry was the norm, so that two or more component failures would have been required to cause 

an unintended throttle opening. The only other potential cause of the wide-open-throttle condition 

was the misapplication of a driver’s foot. Other malfunctions were found that could cause modest 

increases in engine power (up to 0.3g), and may be difficult to detect in a post-incident 

investigation. The researchers stated that the engine power increases (engine surges) were not large 

enough to cause a sudden acceleration incident, but might startle the driver into a pedal 

misapplication. 

In other studies, no relationship was found between pedal design and unintended 

acceleration (UA) or pedal misapplication events. In a simulator study using 114 subjects ages 14 to 

81, Bracket, Pezoldt, Sherrod, and Roush (1989) found no significant differences in either foot 

movement time (from accelerator to brake) or pedal application errors (including wrong pedal, both 

pedals, contacting the pedal with less than half of the foot, and hesitation in foot movements) for 

three lateral pedal separation configurations. The three configurations included the recommended 

configuration (3 inches of separation) plus two configurations bracketing the recommended 

configuration (2 inches and 5.75 inches). Most of the performance errors were observed when foot 

movements were made from the floor to the pedals, rather than from one pedal to another. High 

pedal error rates (1 in every 10 foot movements) were found for all three pedal configurations, but 

this may have been experimentally induced by restricting the pedals from view, allowing no 

practice trials, starting a large proportion of trials from the vehicle floor rather than from pedal to 

pedal, and constraining response time. 

In the Rogers and Weirwille (1988) study described earlier, the simulator was configured to 

test the prevalence of pedal application errors as a function of pedal, floor, and seating configuration 

in four actual automobiles. The four different pedal configurations corresponded to (1) a sport sedan 

with the brake pedal somewhat above the accelerator; (2) a late-model sport sedan with a floorhinged accelerator; (3) a full-sized sedan with a wide brake pedal well above a center-hinged 

accelerator; and (4) a vehicle similar to the sport sedan, but with the brake pedal lowered somewhat 

so that the vertical separation between the accelerator and brake was smaller. The authors provide 

 8 Automatic brake-shift-interlock is now a requirement as part of Federal Motor Vehicle Safety Standard No. 114, 

effective April 29, 2010.
26

the specific pedal horizontal separation distance, vertical separation distance, pedal height, and 

brake pedal width for each configuration in their report. Of particular importance to this literature

review is that there were no significant differences between configurations in the incidence of 

serious pedal application errors observed in the study. The study authors noted that serious errors 

were very rare, occurring only 15 times throughout the entire experiment. This represents an 

average rate of occurrence of one serious error per 4.8 hours of data collection or one serious error 

per 468 foot movements. The authors cautioned that the failure to find significant differences in the 

occurrence of serious errors among the four configurations may have been the result of sparse data, 

or a real finding, and noted that it was unlikely that the issue could be resolved using simulation 

methods. 

Trachtman, Schmidt, and Young (2005) identified crashes involving pedal application errors 

or unintended acceleration (UA) through evaluations of over 4 million crash narratives between 

1979 and 1998 in the North Carolina crash database. For UA events, the driver believes that his/her 

foot was on the brake, denies it was on the accelerator, and believes the vehicle malfunctioned in 

some way. This happens after startup and shift from park to a drive gear. For pedal error (PE) 

crashes, the driver is aware of the error and reports it to the police officer. These crashes occur at 

startup as well as during turning and braking. A narrative search using 19 keywords resulted in 

236,231 crash narratives. Each crash report provided the year, make, and model of the involved 

vehicle. For each crash vehicle make/model/year, either another vehicle of the same 

make/model/year or a “corporate twin” (a vehicle identical in every respect as the crash vehicle 

type, except for trim and emblems) was located for measurement. Then, peer vehicles were 

identified that were not involved in UA or pedal error crashes in the North Carolina database. These 

peer vehicles were matched with the “corporate twins” on criteria including wheelbase, weight, age, 

classification, and driver age, but different manufacturer. Various measures were taken to allow a 

direct comparison of pedal configurations for a group of crash-involved vehicles and a matching 

group of their uninvolved peers. The sample included 20 UA-involved and 18 pedal-error-involved 

vehicles, each of which was matched with an uninvolved peer vehicle. Three pedal measurements 

were made for each vehicle: (1) the separation between the right edge of the brake pedal and the 

steering wheel centerline, with a positive value being to the right of the steering wheel centerline; 

(2) the separation of the right edge of the brake pedal and the left edge of the accelerator (the 

“gap”); and (3) the vertical separation between the two pedals measured along a line perpendicular 

to the brake pedal surface at rest.

Brake to centerline measurements in this study ranged from -0.12 to 6.27 inches. Across 

incident type, involved vehicles and peer vehicles had nearly identical brake to steering wheel 

centerline measures (mean 2.55 in versus 2.65 in). This difference was not significant, nor was the 

interaction between incident type (UA or PE) and vehicle type (involved versus peer). These 

findings indicate that location of the brake pedal laterally from the steering wheel centerline was not 

factor in either UA or PE incidents. The crash involved vehicles had slightly smaller horizontal 

pedal separation than the peer vehicles (mean 2.44 versus 2.72 in), but this difference was not 

significant, nor were any differences between the subgroups. This suggests that horizontal 

separation is not a factor in either PE or UA incidents. Finally, the involved vehicles had slightly 

larger vertical separation than the peer vehicles (mean 2.62 versus 2.33 in), but this differences 

failed to reach significance, as did differences between UA and PE vehicles and their peers. Thus, 

there is no evidence that the vertical separation between the brake pedal and the accelerator pedal 

was a factor in either UA or PE incidents.
27

The authors concluded that there is no evidence that vehicles with leftward-biased pedal 

clusters, or those with a small gap are prone to either UA or PE crashes. Instead, response errors 

resulting in variability in movement control are likely responsible for pedal misapplications.9

Vernoy and Tomerlin (1989) conducted a study to test the hypothesis that misperception of a 

vehicle’s centerline is related to pedal misapplication. Hypothetically, if a driver misperceives the 

centerline of the vehicle to be to the right of actual center, then during an emergency the driver may 

place his/her foot to the right of the intended position. Because the accelerator is placed to the right 

of the brake, drivers may press the accelerator, thinking they are pressing on the brake.

The study compared driver perception of centerline in eight vehicle models. Subjects first 

completed three trials to identify the centerline of the vehicle by choosing one of 48 LEDs that were 

projected on a wall approximately 23 feet in front of the subject. Next, they responded to slides 

projected on the wall instructing them to step on the brake, step on the accelerator, move the shift 

lever, signal left, or signal right. There were five practice slides, followed by nine slides in each of 

the two vehicles being compared. Between slide presentations, subjects were instructed to rest their 

feet flat on the floor. On one slide that presented a stop sign, the experimenter shouted into an 

intercom “Stop! Hit the brakes!” to simulate a panic stop. Subjects’ foot positions on the brake were 

recorded for each panic stop, and pedal errors were coded as one of two types: (1) foot placement 

between the pedals or on both pedals; or (2) foot placement on the accelerator. At the end of the 

session, subjects placed a dot on the dashboard to indicate the center of the vehicle, before exiting 

the vehicle.

Vernoy and Tomerlin (1989) found that the perceived center of each of the eight vehicles as 

measured by the outside LEDS was to the right of actual center. The deviation from actual center 

ranged from 7 to 20 in, and was significantly greater than 0 for all eight vehicles. Similarly, the 

perceived center of the automobile as measured by inside placement of the adhesive dot showed 

average deviations to the right of center for each of the eight vehicles, ranging from 0.80 to 2.47 in.

The right deviation from center was significantly greater than zero for each of the eight vehicles.

Subjects made 26 pedal application errors during the 258 panic stop trials, including 14 where 

subjects hit the accelerator instead of the brake. There was no significant difference in pedal error

rate across the eight vehicles. To test the hypothesis that pedal error was related to the misperceived 

center of the vehicle, analysts computed correlations between weighted pedal error and both outside 

and inside center measurements. None of the correlations was significant, indicating no relationship 

between the misperceived center of the vehicle and pedal application error. In their discussion, the 

authors noted that real-world error rates were likely lower than observed in the experiment, because 

they designed the experimental situation to elicit errors through placement of the feet on the floor 

between foot movements. Most drivers in actual driving situations would place the foot above the 

brake or accelerator, rather than on the floor. The authors noted that drivers who have a habit of 

placing their feet flat on the floor between movements, such as in parking and starting situations, 

and when using cruise control, may be more likely to make these types of errors than drivers who 

 9 Potential confounds in the study methodology included: (a) the twin vehicles selected for measurement were not 

always the same make, model, and year as the crash vehicles; and (b) although the peer vehicles had not been involved 

in pedal error crashes in North Carolina, they may have been involved in such crashes elsewhere. Therefore, the 

conclusions regarding pedal geometry of case (“twins”) versus comparison (“peer”) vehicles should be viewed with 

some caution.
28

keep their feet close to the brake or accelerator. This experiment did not test whether misperception 

of the centerline in a moving vehicle would affect pedal misapplication rate.

The findings of this study are interesting in light of the NTSB’s discussions regarding a 

possible reason for the Santa Monica driver’s inadvertent activation of the accelerator (NTSB, 

2004). The NTSB report indicated that the driver may have been out of his usual driving position 

when the crash occurred. This is because moments before the crash, he had parked his car and slid 

across the vehicle to the passenger side to deposit a letter through the passenger window of his 

vehicle into a curbside mailbox. Citing Schmidt (1989), the NTSB stated that an error in response 

execution could result from a driver’s head or body being out of position, such that a normal, 

habitual movement results in an error (in foot placement). Given the widespread misperception of 

the vehicle centerline (i.e., to the right of the vehicle) noted by Vernoy and Tomerlin, if the Santa 

Monica driver, upon his return to the driver seat, was positioned farther to the right of center in his 

vehicle than normal, he may have misestimated the foot movement necessary to hit the brake. 

Driver Workload

Tomerlin and Vernoy (1990) reported on a field study that followed the static tests described 

by Vernoy and Tomerlin (1989). In this study, 169 subjects were assigned to one of the eight 

vehicles used in the static tests; subjects who participated in the static tests were assigned to a 

different vehicle for the field tests. Subjects drove through a short serpentine course, and were 

directed to one of four areas marked for reversing maneuvers. A researcher sitting in the passenger 

seat instructed the subject to place the gear lever into Park, shift to Reverse, and back through a 

parallel line of rubber cones. After the subject shifted into reverse, the researcher opened the 

accelerator to full throttle using a hand lever, and made observations about the subject’s use of the 

brake pedal and ability to stop the vehicle. One subject hit the accelerator instead of the brake, and 

continued pressing the accelerator until the car ran off the back of the course and was stopped by 

the researcher using an ignition kill switch. Four other subjects made partial errors but corrected 

their mistake. Three of these subjects pressed on both pedals momentarily, and one subject 

accelerated briefly before applying the brake.

In another study using 130 subjects driving in 3 different passenger cars under 3 different 

driving situations, Tomerlin (1998) found that experimenter activation of maximum idle speed 

resulted in confusion by 2 subjects during a reverse-driving test: they applied the accelerator when 

they meant to brake. Tomerlin and Vernoy (1990) concluded that pedal misapplications can be 

induced, as shown in the laboratory and field studies, and can be a problem for all automatic 

transmission cars and all categories of drivers.

Pollard and Sussman (1989) noted that driver workload may influence the likelihood of a 

pedal misapplication, since unexpected movements of the vehicle may briefly overload and startle 

the driver, resulting in a control error. The human startle reflex, as initiated by the actions of the 

vehicle, is controlled by non-cognitive areas of the central nervous system, and may take 

precedence over conscious efforts to control the vehicle. When a driver is forced to respond more 

quickly than usual to a stimulus, the likelihood of an error increases. If the idle speed abruptly and 

unexpectedly jumps, causing even a brief or slight acceleration, a driver who must respond instantly 

is more likely to partially or entirely miss the brake than a driver making a planned action. Pollard 

and Sussman (1998) referenced the work of Tomerlin and Vernoy (1990) as evidence that startling a 
29

driver (through a surprise acceleration) may result in that driver pressing the accelerator when he or 

she intended to press the brake. 

Schmidt and Young (1997) also provided evidence that startle or surprise stimuli produce 

errors. When these experimenters unexpectedly tapped the arms of subjects who were performing a 

two-choice reaction time task (or introduced a “click” via headphones), subjects’ reaction time was 

quicker, but their response movements were in the wrong direction (Gielen, Schmidt, and van den 

Heuvel, 1983). Citing Proctor and van Zandt (1994), Schmidt and Young label this phenomenon a 

speed-accuracy trade off; and when a startling event requires an immediate response, more errors 

occur in two-choice situations. In addition, startling stimuli (such as loud sounds or bright visual 

signals) have been associated with more forceful movements, relative to less startling events 

(Angel, 1973; Ulrich and Mattes, 1996). 

NEWS MEDIA AND DATA MINING

Data Limitations

News Media Data. Several issues plague the use of news media reports to determine the 

incidence of pedal misapplication crashes over time and to describe the characteristics of drivers 

who make such errors. These include archiving issues, trends in the media, and missing data. With 

regard to archiving issues, particularly with Google News, the number of archived media hits of any 

type decreases as the search goes back in time. Newspapers often do not have the capacity on their 

Web servers to house multiple years of archived stories, so they “weed them out.” Other news 

databases, such as LexisNexis and NewsBank, continually add new sources over time. For these 

reasons, a search spanning 10 years will produce more “hits” in the most recent years than in prior 

years. 

A related issue is that not all newspapers archive their stories on the Internet. For example, 

Google News is limited to publications that archive their news stories on the Internet Other news 

sources may archive their media on their Web sites, but do not make their archive available to 

media databases. Publications that operate subscription-based Web sites, such as the Wall Street 

Journal, often do not provide free full-text versions to Google News users. Similar to the issue with 

Google, publications may choose not to provide their full-text articles to LexisNexis and America’s 

Newspapers. For example, America’s Newspapers includes the following National newspapers in 

their resource: Atlanta Journal-Constitution, Boston Globe, Chicago Sun-Times, Chicago Tribune, 

Denver Post, Houston Chronicle, Richmond Times-Dispatch, San Francisco Chronicle, St. Louis 

Post-Dispatch, Washington Post and Washington Times. While this is an impressive list, it does not 

include every major U.S. National newspaper. 

Another factor is competing and/or complementary issues in the media. For example, a high 

profile crash, such as the “Farmer's Market” crash in California, can raise the visibility of this issue 

tremendously, leading media across the country to pick up this story and similar stories in their own 

markets. On the other hand, when there are large competing issues in the media—for example a 

presidential election—then media outlets might skip “pedal error” stories completely. There may 

also be a bias in reporting only the most “news worthy” incidents: a pedal misapplication crash

involving a middle-aged driver with minor property damage and no injuries will likely not make the 
30

news, where crashes involving fatalities, serious injuries, or heavy property damage—especially if 

teenage or older drivers are involved—probably will.

The final issue surrounding the use of news media in describing pedal misapplication 

crashes is the amount of missing data. News reports of vehicle crashes vary in the amount of detail 

provided. Some reports consist of only a few sentences while others describe the crash 

circumstances in great detail. As a result, the database created using information provided in the 

news reports was missing a great deal of data characterizing the drivers, their vehicles, the crash 

locations, the pre-crash maneuvers, and other crash specifics. 

Crash Data. Both of the crash databases used in this project (NMVCCS and the North 

Carolina State crash database) were limited by the lack of a field to identify pedal misapplication 

crashes. Such crashes could be identified only if: (1) the driver admitted making the error; (2) the 

reporting officer described the driver’s pedal misapplication in the crash narrative field of the crash 

report form; and (3) our search strategy contained all the phrases (and spellings) that officers may 

have used to describe the pedal misapplication. There is a strong possibility that a subset of pedal 

misapplication crashes was not identified, and was included in “all other crash” set; for this reason, 

our analysis may understimate the prevalence of pedal misapplication crashes.

A further limitation of the NMVCCS data is that it does not include crashes occurring in 

parking lots. Aside from these missing incidents, and the associated information lost to this analysis, 

a bias in the ages of the drivers included in the sample drivers who made pedal application errors 

may be introduced by this limitation. This could happen if drivers in a certain age cohort (e.g., older 

drivers) are more likely to experience pedal misapplication crashes while performing parking 

maneuvers than on-road maneuvers. The NMVCCS data also is restricted to crashes involving at 

least one passenger vehicle needing to be towed from the crash scene, so could be expected to 

represent a more serious subset of crashes.

An additional limitation of the North Carolina crash database in determining the prevalence 

of pedal misapplication crashes is the property damage threshold of $1,000. Pedal misapplication

crashes that resulted in property damage below $1,000 are not included in the crash database unless 

they also resulted in a fatality or an injury. Also, crashes that occurred on private property do not 

meet the State’s criteria for a reportable crash; however, some local law enforcement agencies 

choose to report some crashes on private property. Therefore the private property crashes that are 

included in the database are an underrepresentation of their actual prevalence.

With these caveats in mind, the following sections describe the prevalence of pedal 

misapplication crashes and the driver, roadway, and vehicle characteristics associated with these 

events. 

Prevalence of Pedal Misapplication Crashes

The findings from analyses of both the NMVCCS and the North Carolina State Crash 

Database indicate that pedal misapplication crashes account for less than 1% of all crashes. As 

noted earlier, however, the absence of any codes on police crash reports to indicate that a crash 

resulted from a pedal misapplication is likely to have caused the prevalence of these incidents to be 

underestimated. Even if such codes were present, it is unclear whether law enforcement officers, 

who rely on self-reports of behavior, could accurately and reliably apply them.
31

The media analysis identified 178 pedal misapplication crashes in 2009. Based on a total of 

5,505,000 police-reported crashes in the United States in 2009 (NHTSA, 2010), this represents less 

than 1% of all crashes (.003%). This, too, is likely to be an underestimation, based on archival 

issues; competing stories; availability of free, full-text articles in news databases; and a bias in 

reporting of newsworthy-only events.

Table 2 presents the number of pedal misapplication crashes versus all other crashes in 

North Carolina, by crash type, for the years 2004-2008. Statewide, there were 1,398,034 crashes.

Pedal misapplication crashes accounted for 2,411 events, or less than 1% of all crashes (0.2%). This 

proportion is identical to that uncovered in the weighted analysis of NMVCCS crashes 2005-2007, 

shown in Table 3, which used the same method of pedal application error identification but is based 

on a sample of more serious crashes occurring on roadways only.

Table 2. Comparison of Crash Types for Pedal Misapplication Crashes Versus

All Other Crashes. 

(North Carolina State Crash Database, 2004-2008)

Crash Type Pedal Misapplication Crashes All Other Crashes

Number Percent Number Percent

Missing 2 0.08 377 0.03

On-road - property damage only 653 27.08 718,891 51.51

On-road - fatal 1 0.04 7,114 0.51

On-road - non-fatal injury 395 16.38 384,962 27.58

non-reportable 87 3.61 133,383 9.56

private property 81 3.36 9,278 0.66

PVA* - property damage 980 40.65 125,489 8.99

PVA - non-fatal injury 212 8.79 15,980 1.15

PVA - fatal 0 0 149 0.01

Total 2,411 100 1,395,623 100

*Public Vehicular Area, generally parking lots.

North Carolina data (Table 2) show pedal misapplication crashes resulted in slightly lower 

proportions of non-fatal injuries compared to all other crashes (25.2% versus 28.7%), collapsing 

across location (PVA and on-road). Pedal misapplication crashes resulted in slightly larger 

proportions of property-damage-only crashes, compared to all other crashes (67.7% versus 60.5%).

There was 1 fatality resulting from a pedal misapplication crash (.04%), but the all other crash set 

resulted in 7,263 fatalities (0.5% of the crashes). 

Interestingly, nearly half (49.4%) of the pedal misapplication crashes occurred in parking 

lots or other PVAs, compared to only 10.1% of all other crashes, which may account for the nearabsence of fatal crashes among pedal misapplication crashes, compared to all other crashes.

However, pedal misapplication crashes in parking lots resulted in a larger percentage of non-fatal 

injuries than all other crashes in parking lots (8.79% versus 1.15%). The majority of the non-pedal 

misapplication crashes occurred on-road (79.6%), compared to only 43.5% of the pedal 

misapplication crashes. Pedal misapplication crashes occurring on-road resulted in a smaller 
32

percentage of non-fatal injuries than all other crashes (16.38% versus 27.58%). However, these 

percentages are affected by the different distributions of on-road crashes. The percentage of on-road 

pedal misapplication crashes that result in injury or death (37.8%) is about the same as the 

percentage of all other on-road crashes that result in injury or death (35.3%). In contrast, pedal 

misapplication crashes occurring in parking lots and PVAs are more likely than all other crashes to 

result in injury or death (17.8% versus 11.4%), in part due to pedestrian involvement.

Table 3. Prevalence of Pedal Misapplication Crashes in the NMVCCS Sample 2005-2007 

(Weighted).

Data Collection Year

Number and Percentage of Crashes by Type:

Total

Pedal Misapplication Crashes All Other Crashes

2005 865

(0.2%)

399,118

(99.8%) 399,983

2006 1,973

(0.2%)

851,478

(99.8%) 853,451

2007 2,090

(0.2%)

930,662

(99.8%) 932,752

Total 4,928

(0.2%)

2,181,258

(99.8%) 2,186,186

Driver Age

Driver age was available for only 683 of the 899 pedal misapplication crashes identified in 

the news media and 2,399 of the 2,411 crashes identified in the North Carolina State crash database.

Figures D-1 and D-2 in Appendix D present frequency distributions of pedal misapplication crashes

by driver age for these two data sources. Due to the small number of crashes identified in the 

NMVCCS database, NMVCCS findings by age are not included in this discussion. Although the 

media analysis and the North Carolina crash analysis both show higher crash involvement at both 

ends of the age distribution, the media analysis showed smaller proportions of younger drivers and 

larger proportions of older drivers than the North Carolina crash analysis.

Figure 1 shows the Percentage of pedal misapplication crashes involving drivers by 5-year 

age groupings from the news media analysis (red bars), contrasted against the percentage of

licensed drivers in the U.S. population for each age group (green bars).10 Figure 2 shows the

percentage of pedal misapplication crashes involving drivers by 5-year age groupings from the 

North Carolina crash analysis (red bars), contrasted against the percentage of licensed drivers in 

North Carolina by age group (green bars).

11 The ratio of the two percentages is presented above 

each set of bars, providing an indication of the degree to which each age group is represented in 

 10 Statistics describing the population of licensed drivers in the United States by age were obtained from Table DL-22 

Highway Statistics (FHWA), averaged across the years 2000 to 2008 (data for the years 2009 and 2010 were not 

available on FHWA’s Web site as of the time this report was prepared). 11 Averaged across the years 2004-2008 from Table DL-22 Highway Statistics (FHWA).
33

pedal misapplication crashes versus their representation in the driving population. Ratios greater 

than one indicate that the group is overrepresented and less than one indicates underrepresentation.

The media analysis (see Figure 1) showed that drivers younger than 20 were overrepresented 

in pedal misapplication crashes by a factor of 2.38 times their representation in the driving 

population. Drivers 20 to 64 were underrepresented in pedal misapplication crashes, compared to 

their proportions in the driving population. Those 65 to 69 were slightly overrepresented, while 

those age 70 to 74 were represented in crashes involving pedal misapplications at nearly twice their 

proportion in the driving population (1.90). The risk increased more sharply as age increased, 

beginning at age 75.For drivers ages 85 and older the relative risk climbed to 12.6.Thus, while pedal 

misapplication crashes were prevalent among both younger and older drivers, older driver 

involvement increased sharply in relation to their proportion among the population of licensed 

drivers. 

Figure 1. Percentage of Drivers in Pedal Misapplication Crashes Reported by the Media 

(n=683) in 2000-2010 Versus Percentage of Licensed Drivers in the United States by 5-

Year Age Groupings (n= 198,741,423) 

0%

2%

4%

6%

8%

10%

12%

14%

16%

18%

<20 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85+

Age Group

Percent

Percent of Pedal-Misapplication-Crash-Involved Drivers

Percent of US Licensed Drivers

2.38

0.62 0.38 0.30 0.22 0.34 0.30 0.38

0.69

0.85 1.24

1.90

3.51

7.24

12.56
34

The North Carolina crash analysis (see Figure 2) showed that on a per-age-group basis, the

percentage of pedal misapplication crashes among the oldest drivers did not approach the level 

observed in the young novice driver group; however, the overinvolvement rate of drivers 85 was

nearly equal to that of drivers less than 20 (4.96 and 5.09, respectively). Older driver involvement in 

pedal misapplication crashes was elevated beginning at 70, in comparison to their proportion in the 

population of licensed drivers. While the pattern of involvement by 5-year age groups in both 

analyses followed the same inverted U-shape, the proportion of drivers 75+ identified from the 

North Carolina crash data was half that identified in the media analysis. The differences in the 

findings regarding age may be explained by a bias in crash event reporting in the media reflecting 

what is considered newsworthy. This bias should not exist in police-reported crash data, due to the 

criteria for reporting crashes.

In one of the most striking results of this analysis, Figure 3 shows percentage of drivers in 

pedal misapplication crashes by 5-year age groupings, contrasted against the proportion of drivers 

in all crashes in North Carolina during the same time period.12 This figure shows the highest 

percentage of crashes involving pedal application errors in the 16-20 driver age group and the group 

76 and older, accounting for 16.7% and 17.5% of the pedal misapplication crashes, respectively.

Looking at all crashes (blue bars), the percentage of crash-involved drivers decreased with 

increasing driver age. Comparisons of driver age in pedal misapplication crashes versus all crashes 

shows higher pedal misapplication crash involvement for the following age groups: younger than 

 12 The number of drivers who were in crashes s statewide is larger than the number of crashes statewide, because 

crashes often involve multiple vehicles/drivers. These data are for all drivers, regardless of fault. 

Figure 2. Percentage of Drivers in Pedal Misapplication Crashes (n=2,399) in 2004-2008 

Versus Percentage of Licensed Drivers in North Carolina, by 5-Year Age Groupings (n= 

6,301,233) 

0%

2%

4%

6%

8%

10%

12%

14%

16%

18%

20%

<20 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85+

Age Group

Percent

Percent of Pedal-Misapplication-Crash-Involved Drivers

Percent of NC Licensed Drivers

5.09

1.06 0.83 0.67 0.51 0.53 0.49 0.51 0.56 0.62 0.98 1.81 2.17 4.01 4.96
35

1613, 16-20, 66-70, 71-75, and 76+. The largest dispairty was for drivers 76 and older. Although 

they had the smallest representation in all crashes (3%), most likely due at least in part to reduced 

driving exposure, they rival the young-novice drivers in terms of their representation in pedal 

misapplication crashes (17%).

Driver Sex

Driver sex was not reported in the North Carolina data for 11 of the 2,411 drivers who made 

pedal application errors. For the remaining 2,400 crashes, males accounted for 37% and females 

63%. Table 4 shows that within each of five broad age groups, larger proportions of females than 

males were involved in pedal misapplication crashes. Statewide crash data for all crashes by driver 

sex for the years 2004 – 2008 show that males accounted for 56% of crashes and females 44%.

Thus, female drivers appear to be overrepresented in crashes involving pedal application errors, 

compared to their representation in all crashes.

The findings describing driver sex in pedal misapplication crashes in the NMVCCS analysis 

(males 35%, females 65%) and the media analysis (males 36%, females 64%) both corroborate the 

proportions found in the North Carolina data. This is the most consistent finding across the different 

analyses conducted in this study.

 13 In North Carolina, the minimum age for obtaining a learner’s permit is 15.

Figure 3. Percentage of Crash-Involved Drivers by 5-Year Age Groupings, for Drivers 

Who Made Pedal Application Errors (n=2,399) Versus All Drivers in Other Crashes 

(n=2,228,056)

 

0%

2%

4%

6%

8%

10%

12%

14%

16%

18%

20%

<16 16-20 21-25 26-30 31-35 36-40 41-45 46-50 51-55 56-60 61-65 66-70 71-75 76+

Driver Age Group

Percent of Drivers

Pedal-Misapplication-Crash-Involved Drivers

All Crash-Involved Drivers

6.81

0.62

1.12

0.73

0.60 0.55 0.57

0.64

0.66

0.82

1.04

2.10

3.38

6.42
36

Table 4. Proportion of Males to Females by Age Group, for Drivers in Pedal 

Misapplication Crashes.

(North Carolina State Crash Database, 2004-2008, n=2,393)

Driver Age Group Driver Sex

Male Female

<21 39% 61%

21-35 41% 59%

36-55 32% 68%

56-75 35% 65%

76+ 37% 63%

Driver Height

Data describing driver sex in pedal misapplication crashes may be confounded by driver 

height, as females are generally shorter than males. Certified Driver Rehabilitation Specialists 

(CDRSs) who participated in the panel meeting in this project stated that because women are 

smaller than men, their “carfit” in the driver’s seat is often worse. Accordingly, we conducted 

analyses of the heights of drivers involved in pedal misapplication crashes using data extracted from 

the North Carolina license database. Driver height was available for 772 males and 1,369 females.

Figure 4 shows a reasonably normal distribution of driver heights for the total sample of 2,141 

drivers in pedal misapplication crashes (collapsing across sex), while Figure 5 segments this 

distribution according to driver sex. 

Descriptive statistics describing driver height by sex as well as across the sample are shown 

in Table 5.This table includes a summary of anthropometric data collected in the United States on 

7,943 males and 9,067 females ages 20 and older (National Health and Nutrition Survey 

[NHANES] data for the years 1988-1994).The data in this table indicate that the average height of 

the males and females in the sample of drivers who were involved in pedal misapplication crashes is 

representative of the average height of males and females in the U.S. population.

Table 5. Driver Height by Sex for Drivers in Pedal Misapplication Crashes Compared With 

NHANES Anthropometric Data Describing Height by Sex of the U.S. Population.

Statistic

NC Drivers in Pedal Misapplication 

Crashes 2004 – 2008

NHANES 1988 – 1994 

Drivers Age 20+

Total Males Females Male Female

Number of Subjects 2,141 772 1,369 7,943 9,067

Height Range (in) 50-80 60-80 50-75

Mean Height (in) 66.24 69.7 64.27 69.1 63.7

Standard Deviation Height (in) 3.89 3.25 2.62

Median (50th Percentile) Height (in) 66 70 64 69.1 63.7

75th Percentile Height (in) 69 72 66 71.0 65.5

The average height—also the median height—of the sample was 66 inches (5 ft and 6 

inches). For the crash-involved sample of drivers, 81% of the females were 66 inches or less 

compared to 16% of the males. The 75th percentile height of a driver involved in a pedal 

misapplication crash was 69 inches (5 ft and 9 inches); 98% of the females were 69 inches or less, 
37

0

25

50

75

100

125

150

175

200

225

250

50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80

Driver Height (Inches)

Number Pedal-Error-Crash-Involved Drivers

Male

Female

Figure 5. Distribution of Drivers in Pedal Misapplication Crashes by Height and Sex 

(N=2,141)

(North Carolina State Crash Database, 2004-2008)

Figure 4. Distribution of Drivers in Pedal Misapplication Crashes by Height, Across Sex 

(N=2,141)

(North Carolina State Crash Database, 2004-2008)

0

50

100

150

200

250

300

50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80

Driver Height (Inches)

Number of Pedal-Error-Crash-Involved 

Drivers (collapsed across sex)
38

compared to 44% of the males. NHANES data indicate that 75% of the female population is 65.5 

inches or shorter, while only 10% of the male population is 65.5 inches or shorter.

Thus, short drivers were overrepresented in this sample of drivers involved in pedal 

misapplication crashes. At the same time, females comprised almost two-thirds (64%) of this 

sample, suggesting that height (a proxy for driver fit in the vehicle) may be a factor in pedal 

misapplication crashes involving more females than males. One caution is that height in the driver 

license file is self-reported, and represents standing height. There are no lower limb driver 

anthropometric data in the license file that describe “fit” of pedal misapplication crash-involved 

drivers in their vehicles.

Driver height was not reported in any of the news media reports, and it was available only 

for 23 of the 31 pedal misapplication crashes identified in NMVCCS.

Driver License Status and Experience at Time of Crash

Table 6 presents the license status for the drivers identified from the North Carolina State 

crash database, and a descriptive summary of the ages of the drivers with each license type. The 

date of first licensure was extracted from the license database, and this was used to determine the 

number of days from first licensure to the pedal misapplication crash. These data were available 

only for North Carolina drivers with full licenses, permits, graduated driver licenses, and those 

whose licenses had expired. 

For this analysis, experienced drivers were defined as those with four or more years of 

driving experience. Inexperienced drivers included those with less than four years of driving 

experience, unlicensed drivers (including those with ID cards only) and ineligible drivers. Using 

these criteria, there were 1,428 experienced drivers involved in pedal misapplication crashes (63%) 

and 835 inexperienced drivers involved in pedal misapplication crashes (37%)14. The mean age of 

the experienced drivers was 57.8 years (s.d. = 21.5) and the mean age of the inexperienced drivers 

was 27.2 years (s.d.=14.1). Males and females were roughly equally represented among the 

experienced and inexperienced groups (with 39% of the males and 35% of the females classified as 

inexperienced).

The majority of drivers involved in pedal misapplication crashes were fully licensed in the 

State of North Carolina (69%). Of these drivers, 83% were experienced and 17% were 

inexperienced. 

 14 Driver experience could not be assessed for 146 drivers with out-of-State licenses (146 drivers) and was missing for 2 

drivers with full licenses.
39

Beginning drivers—those 18 and older with permits to drive in North Carolina, and those 15 

to 18 holding a North Carolina graduated driver license (GDL) at any level—accounted for nearly 

12% of the drivers who committed pedal application errors.

15 Of these drivers, 6% were 

experienced and 94% were inexperienced. The 278 beginning drivers ranged in age from 15 to 67 

(mean = 21.8, s.d. = 10.1). 

Those without licenses (including those holding only an ID card) accounted for another 12% 

of the crashes resulting from pedal application errors. All were considered inexperienced.

The 27 drivers who allowed their licenses to expire accounted for slightly over 1% of the 

population of drivers who crashed as a result of a pedal application error. Of these drivers, 22 were 

experienced (81%) and 5 were inexperienced (19%).

Table 6. License Status of Drivers in Pedal Misapplication Crashes

(North Carolina Crash Database Sample)

Type of License at Crash Number of 

Drivers

Percent

of 

Sample

Age Range Mean 

Age

Standard 

Deviation Age

Full 1,675 69.47% 18 - 95 54.0 22.6

Out-of-State License 146 6.06% 14 - 97 43.8 22.1

Level 3 Graduated Driver License 34 1.41% 16 - 19 17.4 1.0

Level 2 Graduated Driver License 76 3.15% 16 - 17 16.3 0.5

Level 1 Graduated Driver License 66 2.74% 15 - 28 16.0 1.7

Permit 102 4.23% 18 - 67 31.0 11.8

Expired 27 1.16% 18 - 87 45.7 24.6

ID Card 105 4.36% 13 - 86 30.2 13.7

Unlicensed 179 7.38% 8 - 64 24.2 11.1

Ineligible 1 0.04% 23

Total 2,411 100.00%

In the NMVCCS dataset, inexperienced drivers accounted for 6 of the 31 pedal 

misapplication crashes (19%). Five of the drivers were driving on license permits, and one driver 

was unlicensed. The ages of the drivers with permits were: 16 (2 drivers), 17, 35, and 41. The 

unlicensed driver was a female age 55.

 15 GDL Level 1 licenses are limited learner permits for drivers at least 15 but less than 18. However, the license data 

showed one Level 1 driver was 28. This person most likely had a permit, instead of a GDL 1 license. The remaining 

Level 1 GDL drivers were 15 to 17. To obtain a Level 1 permit, a driver must complete an approved driver education 

course and pass the written, signs, and vision tests. GDL Level 2 licenses are limited learner permits for drivers at least 

16 but less than 18. To obtain a Level 2 permit, a driver must hold a Level 1 permit for at least 12 months and have no 

convictions for moving violations or seat belt infractions for the preceding 6 months.

GDL Level 3 licenses are full provisional licenses for drivers 18 or older, who have held a Level 2 limited learner 

permit for at least 6 months and have no convictions for moving violations or seat belt infractions for the preceding 6 

months.
40

Crash Location

The North Carolina crash analysis findings indicated that 57% of the pedal misapplication 

crashes were in parking lots or driveways, 42% on roadways, and the remaining 1% at unidentified 

locations. In the media analysis, 77% of the pedal misapplication crashes were associated with 

parking lots and driveways, compared to 23% occurring on-road. In both analyses, older drivers 

were more likely to have been performing a parking maneuver prior to making the pedal application 

error than other drivers. Although both datasets identified parking lots as the most prevalent crash 

locations for pedal misapplication crashes, the North Carolina crash analysis, through its inclusion 

of larger percentages of middle-aged drivers, found a higher proportion of crashes occurring onroad compared to the media analysis (nearly double). Again, this may reflect underreporting of 

crashes involving younger and middle-aged drivers, and overreporting of older driver crashes by the 

media.

NMVCCS researchers only investigated crashes that occurred on trafficways; therefore, no 

crashes occurring in parking lots are included in the entire NMVCCS dataset. The majority of the 

pedal misapplication crashes in the NMVCCS dataset occurred at non-intersection locations (60%).

Intersections were associated with 11% of the crashes, intersection-related locations with 26% of 

the crashes, and entrance/exit ramps with 3% of the crashes.

Like the NMVCCS findings, the North Carolina State Crash database analyses showed that 

intersections were the site of 11% of the pedal misapplication crashes identified (6% at four-way 

intersections and 5% at T-intersections). Intersection-related and exit-ramp locations each 

accounted for 1% of the crashes in the North Carolina analysis. The majority of crashes that

occurred on-road (i.e., not in parking lots) occurred on two-way, undivided roadways (70%). A 

crosstabulation of number of crashes by number of lanes and roadway configuration for the North 

Carolina data indicated that the largest proportion of pedal misapplication crashes that occurred onroad were on two-lane roadways with two-way, undivided traffic (35%). The authorized speed 

limit was not coded for 556 crashes, many of which may have been parking lots. Forty-eight percent 

of the pedal misapplication crashes identified in the North Carolina crash database were on 

roadways with speed limits of 25 mph or slower, 33% on roadways with speed limits between 31 

and 40 mph, 13% on roadways with posted speeds of 41 to 45 mph, and 6% on roadways with 

speed limits above 45 mph.

In the media analysis, 7% of the crashes occurred at intersections, 16% occurred on-road at 

non-intersection locations, and 77% occurred in locations where parking maneuvers are prevalent 

(64% in commercial parking lots, 5% in residential parking lots, 7% in driveways, and 1% in 

parking garages). Table 7 presents crash location by driver age group for 656 news reports where 

both location and driver age were cited. Although commercial parking lots were the most frequent 

location for crashes resulting from pedal misapplication for every age group, drivers in the two 

oldest age categories (56 to 75 and 76 and older) had 20 to 25% more crashes in commercial 

parking lots than drivers 55 and younger, who experienced approximately 50% of their pedal 

misapplication crashes in these locations. On-road crashes were most prevalent in the 21-to-35 age 

group (29%) and least prevalent in the 76+ age group (10%). The highest prevalence of intersection 

crashes occurred in the 36-to-55 age group (13%). 
41

Table 7. Number and Percentage* of Pedal Misapplication Crashes by Location and 

Driver Age Group (Media Analysis, n=656).

Crash Location

Age Group

N 20 or 

younger

21-35 36-55 56-75 76+

Commercial Parking Lot 416 44

(50%)

33

(47%)

37

(47%)

116

(69%)

186

(74%)

Residential Parking Lot 35 7

(8%)

9

(13%)

4

(5%)

8

(5%)

7

(3%)

Driveway 49 9

(10%)

5

(7%)

7

(9%)

8

(5%)

20

(8%)

On-Road (not intersection) 107 18

(20%)

20

(29%)

19

(24%)

24

(14%)

26

(10%)

Intersection 45 10

(11%)

3

(4%)

10

(13%)

10

(6%)

12

(5%)

Parking Garage 4 0

--

0

--

1

(1%)

1

(1%)

2

(1%)

Total 656 88 70 78 167 253

* Percentages of drivers in each age category (column percents)

Environmental and Roadway Conditions

In North Carolina, the majority of the pedal misapplication crashes (69%) occurred during 

the daytime (9 a.m. to 6 p.m.), in clear conditions (78%, with an additional 17% under cloudy 

conditions), and on dry roads (89%). In 77% of the crashes, the roadway was straight and level. In 

99% of the crashes, the roadway condition was not considered by the reporting law enforcement 

officer to be a contributing crash factor. In the news media analysis 77% of the crashes occurred 

between 9 a.m. and 6 p.m.. In the NMVCCS analysis of pedal misapplication crashes, 56% of the 

crashes occurred between 9 a.m. and 6 p.m. (and an additional 24% occurred between 6 and 9 p.m.), 

71% during daylight, 83% on dry roads, and 66% on straight and level roadways. Thus, roadway 

and environmental conditions do not appear to be important contributing factors in pedal 

misapplication crashes.

Table D-1 in Appendix D presents the percentage of crashes by time of day and data source. 

The differences in proportions of crashes by time of day between the NMVCCS data set and the 

other two sources may be related to the smaller percentage of older drivers in the NMVCCS dataset 

(due to the exclusion of parking lot crashes).

Pre-Crash Maneuver

In the North Carolina crash analysis, pedal misapplication crashes were as equally as likely 

to occur while drivers were traveling straight ahead (39%) as when they were performing a parking 

maneuver, including backing (39%). Eleven percent occurred during turning maneuvers, and 5% 

while slowing or stopping. Older drivers (76 and older) were more likely to be performing parking 

maneuvers than any other maneuver, and more frequently than all other driver age groups, who 

were more likely to be going straight prior to their pedal misapplications. Drivers younger than 21 

were turning in 15% of their pedal misapplication crashes; this is nearly twice the proportion of 

drivers 36 and older. Drivers 21 to 35 were turning in 13% of their crashes. Table 8 presents the 
42

overall distribution of pre-crash vehicle maneuvers, while Table D-2 in Appendix D breaks these 

data down by driver age group.

Table 8. Pre-Crash Maneuver (North Carolina Crash Database Sample)

Pre-Crash Maneuver Number Percent

Going straight ahead 929 39%

Parking 600 25%

Backing (takes priority over other maneuvers) 254 11%

Making right turn 119 5%

Slowing or stopping 116 5%

Making left turn 113 5%

Leaving parked position 75 3%

Starting in roadway (mostly from driveways, public or private) 49 2%

Stopped in travel lane (driver still in vehicle) 27 1%

Parked out of travel lanes 19 1%

Avoiding object in road 15 1%

Making u turn 15 1%

Changing lanes or merging 12 0%

Passing 3 0%

Parked in travel lanes 3 0%

Other 59 2%

Total 2,408 100%

In the news media analysis, parking maneuvers accounted for the largest proportion of the 

crashes (61%). Other pre-crash maneuvers reported in the news media were turning (9%), going 

straight (3%), slowing in lane (7%), and startle braking during an avoidance maneuver (20%). Table 

9 presents the pre-crash maneuvers identified in the news media crash sample, for the 661 crashes 

where this information was included in the news report, and Table D-3 in Appendix D presents 

maneuver frequency by driver age group.

Entering a parking space was associated with the highest percentage of crashes reported by 

the media, nearly 50%, for all age groups, except for drivers 36 to 55, who experienced only 31% of 

their crashes while performing this maneuver. For these middle-age drivers, pedal misapplication 

crashes were most often associated with startle braking following an initial collision or loss of 

control of their vehicles. Referring back to Table 7, drivers 36 to 55 had the highest percentage of 

crashes at intersections, compared to other age groups; these are locations where the potential for 

collisions and the corresponding need for avoidance maneuvers is highest.

Drivers 76 and older had the highest percentage of crashes of all age groups while leaving a 

parking space (see Table D-3). These older drivers, along with their younger counterparts 56 to 75, 

also experienced a higher percentage of crashes while turning, than drivers 55 and younger. 

The NMVCCS data showed a different pattern of maneuvers due to the exclusion of parking 

lot crashes: 55% while going straight, 5% while slowing in a traffic lane, 5% while turning, 11% 

while negotiating curves, and 7% while changing lanes.
43

Table 9. Pre-Crash Maneuver (News Media Sample)

Pre-Crash Maneuver/Behavior Number (Percent) of Crashes

Entering parking space 321 (49%)

Leaving parking space 77 (12%)

Turning 58 (9%)

Startle braking following initial collision 51 (8%)

Startle braking following loss of control of vehicle 45 (7%)

Panic stop to avoid collision 27 (4%)

Slowing/stopping for vehicles 24 (4%)

Slowing/stopping for traffic control device 12 (2%)

Slowing/stopping for pedestrians 9 (1%)

Driving in lane 23 (3%)

Parked/still in gear 9 (1%)

Changing lanes 3 (<1%)

Stopped 2 (<1%)

Total 661

Startle or Panic Responses

We read each crash narrative and news article and coded situations where startle or panic 

was stated or inferred, based on what we learned in earlier project tasks about the contribution of a 

startling stimulus to a pedal misapplication. The decision to code startle or panic reactions followed 

from Schmidt’s (1989) discussion in the literature review of “hypervigilant reactions or panic to a 

strong, startling stimulus which seems to be present in unintended acceleration.” Other researchers 

have noted this phenomenon (Freund et al., 2008, Schiff & Oldak, 1993; Schmidt et al., 1997).

The frequency of startle reactions in the analysis sets may be underrepresented due to the 

lack of detail in many of the crash narratives. The situations we coded in the North Carolina crash 

database sample included:

• Startle following an initial collision (e.g., the driver reacts to a crash by hitting the wrong

pedal).

• Startle following loss of control of the vehicle (e.g., the driver panics when the vehicle skids 

or drifts out of the lane, and during the recovery the driver hits the gas instead of the brake).

• Panic stop to avoid a collision (e.g., an animal, vehicle, or pedestrian is in the driver’s 

immediate path, and the driver tries to slam on the brakes to avoid a collision).

• Startle following a driver’s foot slipping from the brake to the accelerator (e.g., the driver 

panics after the foot slips off the brake, and while trying to re-contact the brake, hits the 

accelerator).

Table 10 presents the number of drivers researchers inferred were startled prior to making 

their pedal application error, by startle type. Other startling situations in this table were: passengers 

yelling at the driver to stop; behavior of other drivers or pedestrians in the area; panic after the 

vehicle moved in the wrong direction (driver selected the wrong gear); other drivers blowing their 

horns; ambulance siren; cell phone ringing; lit cigarette landing between a driver and her seat back;

driving on suddenly uneven terrain; a traffic signal suddenly turning red, and the driver panicking to 

stop in time; and panic following an initial pedal misapplication, followed by continued pressing on 

the accelerator. 
44

Table 10. Drivers in Startle-Related Pedal Misapplication Crashes, by Startle Type

(NC Crash Database Sample)

Startle Type Number of 

Drivers

Percent of All Pedal 

Misapplication Crashes 

(n=2,411)

Panic stop to avoid a collision 171 7%

Startle following loss of control of the vehicle 135 6%

Startle following an initial collision 94 4%

Other startling situations 46 2%

Startle following a driver’s foot slipping from the brake to the 

accelerator 16 <1%

Total 462 19%

In 19% of the North Carolina pedal misapplication crashes, drivers were described as 

startled or panicked. According to Schmidt (1989), when drivers are startled or they panic, they 

perceive the sudden stimulus as being life threatening, requiring an immediate solution. The 

response is often an attempt to slam on the brake. The faster a foot movement is made and the 

greater force used in making the movement, the less accurate the targeting, which can lead to a 

pedal misapplication.

Analysis of startle responses shows that as driver age increased, the number of crashes 

associated with startle or panic responses decreased. Table 11 contrasts the percentage of crashes 

associated with startle for each age group with the percentage of that driver age group in the sample.

Table 11 reveals that the youngest drivers were overrepresented in startle-related crashes in 

comparison to their proportion in the sample, while the oldest drivers were underrepresented in 

startle-related pedal misapplication crashes.

In the media analysis, 20% of the drivers were described as startled or panicked, while 58% 

of the NMVCCS pedal misapplication crashes were associated with a startle or panic response, 

based on our review of the crash narratives.

Table 11. Pedal Misapplication Crashes Associated with Startle, By Age Group (North 

Carolina Crash Database Sample)

Driver Age Group Number (and Percentage) of Crashes 

Associated With Startle*

Number (and Percentage) of Drivers 

in Sample

<21 143 (31%) 473 (20%)

21-35 117 (25%) 545 (23%)

36-55 93 (20%) 477 (20%)

56-75 61 (13%) 485 (20%)

76+ 45 (10%) 419 (17%)

All 459 2,399

* Driver age was missing in 3 of the startle-related crashes.
45

Driver Inattention and Distraction

Officers use up to three fields on the North Carolina crash report to code actions of the 

driver that may have contributed to the crash. They coded driver contributing circumstances for 

2,330 of the 2,411 crashes. Table D-4 in Appendix D presents the frequency that each driver action 

was coded as either a first, second, or third contributing factor, and the percentage of crashes in 

which each driver contributing circumstance was a factor.

The most frequent driver contributing factor in the North Carolina crash analysis sample was 

inattention, recorded in 44% of the pedal misapplication crashes in which a driver contributing 

factor was coded. Driver inattention was relatively equally prevalent as a contributing factor within 

each of the five broad age groupings: under 21 (43%), 21 to 35 (44%), 36 to 55 (46%), 56 to 75 

(42%), and 76 and older (44%). 

Driver distraction was coded by the reporting officers as a first, second, or third contributing 

factor in 4% of the crashes (see Table D-4). Together, inattention and distraction were coded as 

contributing factors in nearly half of the crashes resulting from pedal misapplications (48%). As a 

supplemental analysis, we read each crash narrative to determine the kinds of distraction that may 

have contributed to the pedal misapplication. We identified descriptions of distraction in 166 of the 

2,411 pedal misapplication crashes (7%). These are summarized below by type.

• Looking away (42)

• Reaching for an object (30)

• Passengers (19: generally children, but others included passengers arguing or yelling at the 

driver)

• Cell phone (13: 2 were dialing, 1 was texting, 8 were talking, 2 were distracted by the phone 

ringing)

• Adjusting radio or CD player (7)

• Other road user (7)

• Dog in vehicle, in lap or near feet (6)

• Interacting with a curbside device such as entering code into entrance gate (5)

• Insect in vehicle (4)

• Thoughts – preoccupied or upset (4)

• Object in car fell (3)

• Driver dropped object (3)

• Adjusting mirror (2)

• Equipment malfunction (2)

• Eating (1)

• Other (10: e.g., reading map, ambulance siren, something in eye, missed a turn, sneezed)

• Narrative stated driver was distracted, but did not specify the distracter (8)

Table 12 compares the percentage of crashes associated with distraction by age group with 

the percentage of the age group in the sample. It shows that drivers in the two older age groups (56 

to 75 and 76 and older) were underrepresented in distraction-related crashes, and drivers in the two 

youngest age groups (<21 and21 to 35) were overrepresented in distraction-related crashes, based 

on their representation in the sample. 
46

Table 12. Drivers in Distraction*-Related Pedal Misapplication Crashes, by Age Group

(North Carolina Crash Database Sample)

Driver Age Group Number (and Percentage) of Crashes Associated 

With Distraction

Number (and Percentage) of Drivers 

in Sample

<21 46 (28%) 473 (20%)

21-35 53 (32%) 545 (23%)

36-55 39 (23%) 477 (20%)

56-75 21 (13%) 485 (20%)

76+ 7 (4%) 419 (17%)

All 166 2399

* determined through a review of the crash narratives

Driver distraction was reported in 39% of the NMVCCS pedal misapplication crashes. As a 

point of comparison, inattention and distraction factored in 18% of the crashes in the entire 

NMVCCS sample (all crashes, representing 843,804 crashes nationwide between 2005 and 2007)

(NHTSA, 2008, December). Thus, based on the findings from the NMVCCS analyses of pedal 

misapplication crashes, inattention and distraction factored more prominently in pedal 

misapplication crashes than in all crashes.

Driver distraction was present in 12% of the news media articles that mentioned a driver 

contributing factor. This may be an underrepresentation, because the news reports varied greatly in 

the level of detail provided. Drivers 20 and younger, 36 to 55, and 56 to 75 were overrepresented in 

distraction-related pedal misapplication crashes. Drivers 76 and older were less likely than the other 

age groups to be reported distracted, and were under-represented in distraction-related pedal 

misapplication crashes. Drivers 21 to 35 were only slightly more likely to have distraction cited, 

compared to their representation in all pedal misapplication crashes.

Eight of the news media crash reports indicated that drivers were reaching for something.

This included dropped cigarettes and cell phones, something in the back seat, and a tissue. In six 

crashes, the drivers were talking on cell phones. In six others, drivers were looking away from the 

road; this included looking at the sides of the road for a parking space, looking at a man in a 

wheelchair, looking at a spot where the road curves, looking at cars parked along the roadside, 

reading a sign on a storefront, and simply looking down for a second. In three crashes, drivers were 

distracted by a conversation with their passengers, one of whom was in the back seat; the driver 

turned to look at her. Two articles simply stated that the driver was distracted. One driver was 

distracted by a contact lens popping out, which caused her to look away from the road for a second, 

after which her passenger screamed, causing her to slam on the “brakes” (actually the accelerator), 

jump a curb, and drive down a steep bank into a ditch. Other distractions cited in the news reports 

included: a dog jumping into the driver’s lap, driver sneezing, driver untangling a cord to a 

microphone, adjusting the radio, holding food and beverage in hand while exiting a drive through, 

and wandering thoughts.
47

Driver Out of Position

The research team coded drivers who crash narratives reported were reaching for something 

in the vehicle, looking left or right, or who had exited their vehicle and re-entered it quickly when it 

started to roll, or whose seating position was described as unusual, as “out-of-position drivers.”

Drivers described as looking left or right were included, based on a human factors theory that head 

and eye movements can affect the accuracy of foot-aiming movements (Schmidt, 1989). The out-ofposition factor overlaps with driver distraction, because drivers looking away from the roadway and 

reaching for objects are not exclusively directing their attention to the driving task.

Seventy-three of the 2,411 drivers in the North Carolina Crash database sample were coded 

as out of position (3%). This may be an underestimation, as the team only coded this factor if the 

reporting officers included a description in the crash narrative. A summary of the driver behaviors 

that resulted in improper positioning in the driver’s seat included:

• Reaching across the vehicle, or into the back seat, or down into the floorboard area for 

something the driver dropped (29 drivers);

• Re-entering the vehicle to stop it from rolling, after parking but inadvertently leaving it in 

gear (21 drivers);

• Looking left or right (10 drivers);

• Looking left and reaching (5 drivers);

• Driving with the driver’s side door open and the left foot out of the door, while moving a 

vehicle slowly in a parking lot or driveway (3 drivers);

• Driving from the passenger seat or center console area (2 drivers);

• Moving from the passenger seat to the driver’s seat with the vehicle still in gear (1 driver);

• Starting the vehicle from a seating position straddling the center console, not realizing the 

vehicle was in gear (1 driver); and

• Seat positioned too far back for driver to accurately control the pedals (1 driver).

Ten percent of the pedal application error crash narratives in the NMVCCS analysis 

described drivers as “out of position,” and 7% of the news media reports (where a driver factor was 

described) included drivers out of position. The media analysis included 12 pedal misapplication 

crashes associated with drivers looking or reaching to the sides or rear of the vehicle, 5 with drivers 

re-entering the vehicle to hit the brake when it began rolling after being parked (but not in Park 

gear), and 2 with drivers or passengers moving from one seat to another; the driver hit the wrong 

pedal to stop the vehicle when it began rolling. Drivers 36 to 55 had the largest overrepresentation 

with this factor, although those 20 and younger and 21 to 35 were somewhat overrepresented 

compared to their proportion in all pedal misapplication crashes. Drivers in the two oldest age 

groups were underrepresented on this factor.
48

Driver Unfamiliarity with the Vehicle

The literature review revealed that drivers unfamiliar with the vehicle were overrepresented 

in unintended acceleration crashes. This applies to new owners as well as occasional users (e.g., 

parking lot attendants, rental car patrons). After reading each crash narrative and news article, the 

research team coded instances where the driver was described as driving an unfamiliar vehicle.

In the news media analysis, 14 of the 266 pedal misapplication crashes that included a driver 

factor as a contributing cause, cited drivers in unfamiliar vehicles (5%). Reports cited age in 10 of 

these 14 crashes. Drivers 21 to 35 and 36 to 55 appeared to be overrepresented in pedal 

misapplication crashes in reports that cited this driver factor, compared to their representation in all 

pedal misapplication crashes, while drivers 76 and older were underrepresented. Two drivers

reported to be unfamiliar with the vehicle were driving rental vehicles (SUVs). Two other drivers 

were operating newly purchased vehicles, and two were test driving a vehicle for sale. Two crashes 

occurred when car dealership employees were moving display or newly purchased vehicles in the 

car dealership lots. One crash occurred at a car wash, when an employee was moving a customer’s 

vehicle. Two drivers new to bus companies (one with 3 weeks experience as a commercial bus 

driver) were involved in pedal misapplication crashes. One of these crashes involved distraction 

when the driver tried to untangle a microphone cord while driving. Two drivers in vehicles with 

adaptive equipment were involved in pedal misapplication crashes. One driver was not handicapped 

and was unfamiliar with the vehicle’s hand controls. The other driver (age 84) was described as 

unfamiliar with the vehicle’s foot controls for the disabled. 

The research team uncovered 25 crash records in the North Carolina crash analysis (1%)

describing the driver as unfamiliar with the vehicle. Ten involved drivers in cars that belonged to 

friends or relatives; five were driving rental vehicles (1 was a U-Haul truck, which likely had a 

different pedal and seating configuration than a standard passenger vehicle); two were not 

accustomed to driving vehicles with automatic transmissions; two were car-wash attendants; two 

indicated they were “not accustomed” to the vehicle and one stated that he/she was “not accustomed 

to the gas and brake pedals in the vehicle.” One driver had just purchased the vehicle that week.

One driver was parking a vehicle equipped with “handicapped braking equipment” which was 

unfamiliar to the driver. One driver stated that she was test driving a vehicle that had a gas pedal as 

big as the brake pedal, so she thought she was hitting the brake when she hit the gas.

There were no pedal misapplication crashes attributed to driver unfamiliarity with the 

vehicle in the NMVCCS analysis.

Driver Medical Conditions or Functional Impairments

The North Carolina crash reports contain a field for coding the physical condition of the 

driver at the time of the crash. The selections provided on the form are very general, as shown in 

Table D-5 in Appendix D. Inspection of Table D-5 indicates that the large majority of drivers (93% 

across all age groups) were “apparently normal.” Slightly higher percentages of drivers in the 

younger age groups were “apparently normal” drivers (96%) compared to drivers in the oldest age 

group (90%).
49

Many of the police narratives contained more detailed information about the drivers than 

could be coded on the police crash report form. In addition, there appeared to be inaccuracies in the 

coding of driver physical condition, leading to underrepresentation of medical conditions. For 

example, of the 2,235 drivers coded as “apparently normal,” review of the crash narratives indicated 

the presence of medical conditions for 37 drivers, including the following conditions: partial 

paralysis, casts or splints on the right foot, blacked out, cognitive disorders, multiple sclerosis, 

medical problems with knees, pain in the right leg, and use of a handicapped parking space

(suggesting the presence of a medical or functional condition). Of the 43 drivers coded as 

“unknown,” 5 were described in the narratives as having the following conditions: seizures, back 

pain/spasms, dizzy/blacked out, cast on foot, and using a handicapped parking space.

The following medical conditions (or situations suggesting the presence of medical 

conditions) were uncovered for 77 drivers, following a review of the 2,411 crash narratives in the 

North Carolina crash analysis.

Handicapped 

• 23 drivers: Parked in a “handicapped” parking space (suggesting the driver has a medical 

condition that warranted parking in such a place). One driver was specifically described as 

“handicapped.”

Lower Limb Impairments (Loss of Strength, Sensation, Range of Motion)

• 11 drivers: Wearing a cast on the right foot or leg (note: 2 of these drivers were described as 

driving with the left foot)

• 3 drivers: Brace or splint on foot or leg (note: the driver with a splint on the right knee was 

described as braking with the left foot)

• 1 driver: recent right leg amputation; wearing prosthesis

• 1 driver: Driving a handicapped-equipped van with a hand brake

• 2 drivers: Prior stroke(s) which resulted in little feeling in the right leg

• 1 driver: Couldn’t feel his foot, as it had fallen asleep.

• 1 driver: Right side of body went numb

• 4 drivers: Difficulty (or unable to) move feet and legs

• 3 drivers: Recent surgery, resulting in diminished foot strength and loss of feeling in legs 

(note: 1 of these drivers was described as using the left foot to operate the pedals)

• 2 drivers: Multiple sclerosis

• 2 drivers: Medical problem with knees

• 2 drivers: Right leg pain and discomfort (1 described as using left foot for braking)

• 1 driver: Hurt right foot, so was driving with left foot

• 1 driver: Back pain and spasms

Black Out, Loss of Consciousness, Hypoglycemic Reaction

• 4 drivers: Blacked out (1 may have fallen asleep)

• 1 driver: Seizures

• 1 driver: Blood sugar dropped
50

Cognitive Impairments

• 3 drivers: Cognitive decline or minor mental condition (1 described as confused and not fit 

to drive; 1 asked for a “pan of bread to blow my nose”)

• 2 drivers: Medications /drugs (Prescription narcotics, marijuana)

Other Conditions

• 3 drivers: Sneezed

• 1 driver: Coughing uncontrollably

• 1 driver: Stomach cramps

• 1 driver: Contractions

• 1 driver: Feeling ill and trying to pull over to park

• 1 driver: Unspecified

Combining the two data sources (driver physical condition codes and crash narrative 

review), at least 163 of the 2,411 drivers with pedal misapplication crashes (6.7% of the sample) 

had some type of physical or mental impairment, or other medical condition. Also as indicated in 

Table D-5, 13 drivers were tired; and 25 were impaired by alcohol, drugs, or medications. 

In the news media analysis, 75 of the 266 pedal misapplication crashes with descriptions of 

driver contributing factors included descriptions of medical conditions or medications (28%). News 

reports of drivers parking in handicapped spaces (associated with 26 crashes) or driving vehicles 

with handicapped plates (associated with 4 crashes) were coded as having this factor.

There were no drivers 20 or younger who were cited in the news reports as having medical 

conditions or using medication. Drivers 21 to 35 and 36 to 55 were also underrepresented with this 

factor, compared to their representation in all pedal misapplication crashes.Not surprisingly drivers 

76 and older contributed to the majority of crashes with this driver factor (58%), and were 

overrepresented in comparison to their proportion in all pedal misapplication crashes.Drivers 56 to 

75 were slightly overrepresented as having this factor.

In addition to “handicapped” as described above, specific medical conditions and 

medications reported in the set of news media crashes were as follows.

• Leg, foot, and hip problems (12 drivers): includes 2 drivers with leg cramps; a driver with 

cast on the right foot, another with a broken right foot, and one with an injured right foot; a 

driver with a “neuropathy-related condition” and another with a “condition that causes the 

feet to go numb;” a driver with a flexible cast on 1 leg; a driver who used a cane and could 

not lift the right foot when walking; a driver who used orthopedic shoes; a driver with a 

medical condition that required hand-operated brakes and accelerator; and a driver with a 

hip problem. 

• Black-out (3 drivers)

• Seizure (2 drivers)

• Diabetes (4 drivers)
51

• Arthritic (2 drivers)

• Heart condition (11 drivers): included a driver who possibly had a heart attack just prior to 

the crash, 2 drivers with high blood pressure, 1 who had a triple bypass recently, one who 

had a heart valve installed in recent years, and 1 with heart palpitations after the crash

• Dialysis patients (2 drivers)

• Drivers undergoing chemotherapy treatment (1 driver with breast cancer)

• Early Alzheimer’s disease (1 driver)

• Chronic back problem (1 driver who wore support while driving)

• Spinal injury (1 driver)

• Abdominal pain (1 driver)

• Dizzy/faint (1 driver)

• Medical emergency (2 drivers, including one who was “in a trance”)

• Disorientation (2 drivers)

• Used oxygen tank (1 driver)

• Medications (7 drivers): included two drivers on medication for high blood pressure; 1 

driver taking a painkiller, a tranquilizer, and an antidepressant (Zoloft); a driver taking 

medication for high cholesterol (Lipitor) and quinine sulfate; 1 driver treated with 

chemotherapy; 1 driver taking medication for a heart condition (unspecified); and 1 driver 

using marijuana

In the NMVCCS analysis of pedal misapplication crashes, 29% of the narratives included 

descriptions of medical conditions and 48% described medications, the majority of which were 

potentially driver impairing. The NMVCCS researchers coded 7 of the 31 drivers (22.5%) as having 

a physical factor that may have been relevant to the driver’s pre-crash driving behavior. As a point 

of comparison, in the entire NMVCCS sample (all crashes), representing 2,045,577 crashes where 

driver condition was coded, only 2.4% identified drivers with physical impairments. The medical 

conditions in the sample of pedal misapplication crash-involved drivers included: previous back 

injury, high blood pressure (2 drivers), depression (3 drivers), diabetes, poor eyesight, poor 

circulation in feet, recent heart surgery, allergies, and lack of alertness. A total of 33 medications 

had been taken by the 15 drivers who had used medication in the 24-hour period prior to their pedal 

misapplication crash. The number of medications taken per driver ranged from 1 to 7. Eight drivers 

were taking a single medication, 3 were taking 2 medications, 2 were taking 4 medications, and 2 

were taking 7 medications. The medications comprised the following pharmacologic classes: 

anticoagulants, hypoglycemics, antihypertensives, antidepressants/antianxiety, narcotic analgesics, 

non-steroidal anti-inflammatory drugs, antipsychotics, anticonvulsants, asthma medications, 

sedating antihistamines, non-sedating antihistamines, analgesics, proton pump inhibitors, birth 

control medications, and electrolytes.

Driver fatigue factored in less than 1% of the North Carolina pedal misapplication crashes, 

10% of the NMVCCS crashes, and 2% of the news media reported crashes. Alcohol was suspected 

in less than 1% of the North Carolina pedal misapplication crashes, 3% of the NMVCCS pedal 

misapplication crashes, and 8% of the news media reports of pedal misapplication crashes.
52

Vehicle Make and Year

In North Carolina, officers document the vehicle manufacturer (e.g., Chrysler, Ford, etc.) 

and model year on the crash report form, but they do not record vehicle model. Vehicle make was 

missing in 17 cases. Table 13 shows the make listed for the remaining 2,397 cases by number and 

percentage of cases. Pedal misapplication crashes occurred across 43 vehicle makes, most 

frequently in Fords (16%), Chevrolets (12%), Toyotas (11%), and Hondas (9%). Data describing 

the composition of the fleet of registered vehicles in North Carolina were not available; however, 

Table 13 includes data describing the fleet of vehicles in operation in the United States as of April 

1, 2010 provided by The Polk Company. Vehicle makes associated with large percentages of pedal 

misapplication crashes were also largely represented in the U.S. vehicle fleet. In other words, the 

prevalence of these vehicles in pedal misapplication crashes appears to directly reflect their 

exposure in the vehicle fleet. 

Table 13 also presents the proportion of vehicle makes involved in the media-reported pedal 

misapplication crashes, in those instances where vehicle make was cited, and the vehicle makes 

involved in the NMVCCS sample of pedal misapplication crashes. Interestingly, the NMVCCS 

distribution varied from the overall fleet distribution more than the media distribution, with higher 

than expected proportions of Hondas, Mitsubishis, and Buicks, and a lower proportion of Fords. At 

least some of the discrepancy might reflect the vehicle preferences of a generally younger sample of 

drivers.

Vehicle year was not coded in 22 of the 2,411 pedal misapplication crashes in the North 

Carolina crash analysis sample. Table D-6 in Appendix D presents the number and percentage of

vehicles involved in pedal misapplication crashes by vehicle year, for the remaining 2,389 crashes 

that occurred between 2004 and 2008. Vehicles produced over 5 decades, from the 1960’s to the 

2000’s, were represented in pedal misapplication crashes occurring between 2004 and 2008.

Each model year from 1966 to 1988 was associated with 1% or less of pedal misapplication 

crashes; and the most recent years (2008, 2009) as well. From the late 1980s involvement rates 

climbed gradually to a peak of 8% for the 2003 model year, then declined. Again, these findings are 

most easily understood in terms of exposure. Like vehicle model, the prevalence of vehicle year in 

the fleet of vehicles registered in North Carolina was not pursued.
53

Table 13. Make of Vehicles Involved in Pedal Misapplication Crashes in the North Carolina

Crash Analysis, Media Analysis, and NMVCCS, Compared to Vehicle Makes in Operation in 

the U.S. Fleet 

Vehicle Make

Number of Pedal Error Crashes Percent of Sample

Percent of 

Vehicle Fleet* NC 

Crash 

Database

Media NMVCCS 

(Weighted)

NC Crash 

Database Media NMVCCS (Weighted)

Acura 28 5 0 1.17% 1.02% 0.00% 1.04%

Audi 3 0 0 0.13% 0.00% 0.00% 0.44%

BMW 27 3 0 1.13% 0.61% 0.00% 1.37%

Buick 96 29 532 4.02% 5.89% 10.80% 2.72%

Cadillac 48 16 0 2.01% 3.25% 0.00% 1.51%

Chevrolet 290 51 634 12.14% 10.37% 12.87% 15.40%

Chrysler 52 11 440 2.18% 2.24% 8.93% 2.53%

Daewoo 1 1 0 0.04% 0.20% 0.00% 0.05%

Dodge 124 25 0 5.19% 5.08% 0.00% 6.60%

Eagle 3 0 0 0.13% 0.00% 0.00% 0.07%

Ford 384 69 379 16.07% 14.02% 7.69% 16.64%

GMC 36 8 0 1.51% 1.63% 0.00% 2.95%

Honda 220 45 1392 9.21% 9.15% 28.25% 7.15%

Hyundai 20 7 0 0.84% 1.42% 0.00% 1.71%

Infiniti 12 1 0 0.50% 0.20% 0.00% 0.57%

Isuzu 14 4 0 0.59% 0.81% 0.00% 0.32%

Jaguar 4 2 0 0.17% 0.41% 0.00% 0.22%

Jeep 59 15 0 2.47% 3.05% 0.00% 2.67%

Kia 27 3 0 1.13% 0.61% 0.00% 1.03%

Land Rover 6 1 0 0.25% 0.20% 0.00% 0.17%

Lexus 29 7 338 1.21% 1.42% 6.86% 1.36%

Lincoln 33 19 130 1.38% 3.86% 2.64% 1.09%

Maserati 0 1 0 0.00% 0.20% 0.00% 0.01%

Mazda 51 8 0 2.13% 1.63% 0.00% 1.71%

Mercedes 24 13 0 1.00% 2.64% 0.00% 1.36%

Mercury 97 20 0 4.06% 4.07% 0.00% 1.89%

Mini 1 0 0 0.04% 0.00% 0.00% 0.13%

Mitsubishi 45 5 412 1.88% 1.02% 8.36% 1.08%

Nissan/Datsun 145 21 0 6.07% 4.27% 0.00% 4.74%

Oldsmobile 39 15 311 1.63% 3.05% 6.31% 1.55%

Plymouth 23 1 0 0.96% 0.20% 0.00% 0.66%

Pontiac 65 6 0 2.72% 1.22% 0.00% 3.06%

Saturn 19 6 0 0.80% 1.22% 0.00% 1.38%

Subaru 26 12 0 1.09% 2.44% 0.00% 1.13%

Suzuki 16 2 0 0.67% 0.41% 0.00% 0.33%

Toyota 274 52 360 11.47% 10.57% 7.31% 10.41%

Volkswagen 19 5 0 0.80% 1.02% 0.00% 1.52%

Volvo 29 3 0 1.21% 0.61% 0.00% 0.81%

Total 2389 492 4928 100.00% 100.00% 100.00% 99.38%

*Data from The Polk Company: 233,871,380 vehicles in operation as of April 1, 2010
54

Injuries and Fatalities

Crash reporting law enforcement officers in North Carolina use the following definitions to 

categorize injury severity.

• Killed – Deaths, which occur within 12 months after the crash

• Disabling injury (Type A) - Injury obviously serious enough to prevent the person

injured from performing normal activities for at least one day beyond the day of

the collision. Examples include massive loss of blood, broken bone, and unconsciousness of 

more than momentary duration.

• Evident injury (Type B) - Obvious injury, other than killed or disabling, which is

evident at the scene. Bruises, swelling, limping, soreness, are examples. Class B

injury would not necessarily prevent the person from carrying on normal activities.

• Possible injury (Type C) - No visible injury, but person complains of pain, or has

been momentarily unconscious

• No injury

• Unknown

The 2,411 pedal misapplication crashes in the North Carolina crash analysis set involved a 

total of 5,623 road users. This included the 2,411 drivers who made the pedal application errors and 

the 892 passengers they were transporting, as well as 2,271 occupants of the other vehicles involved 

in these pedal misapplication crashes, and 49 pedestrians. Injury status was missing for 841 “other

road users” (including 3 pedestrians) and 46 “pedal-application-error-vehicle” occupants. Table 14

presents the injury status for the 4,736 road users involved in these crashes, by road user type (pedal 

misapplication vehicle occupant, other vehicle occupant, pedestrian), where the injury status was 

known. 

The majority of road users involved in North Carolina pedal misapplication crashes (82%,

across all road user types) sustained no injuries. Next in prevalence were road users with possible 

injuries (14%) and evident injuries (4%). Ten road users sustained disabling injuries (less than 1% 

of the sample), and 1 road user was fatally injured (also less than 1% of the sample). Of importance 

to this discussion, only 7% of pedestrians involved in pedal misapplication crashes were not injured.

Although none of the pedestrians was killed, 7% received disabling injuries, 46% evident injuries, 

and 41% possible injuries.

Table D-7 in Appendix D presents the number and percentage of drivers who were killed or 

injured (and their injury status), for the 2,367 crashes in the North Carolina analysis where driver 

age and injury status were known. This table does not include injury data for other occupants in the 

vehicle, or in other vehicles involved in the crashes. As shown in Table D-7, the majority of the 

pedal misapplication crashes (85%) resulted in no injury to the driver. The highest percentage of 

crashes in which there was no driver injury occurred for drivers younger than 21 (87%) and drivers 

21 to 35 (88%). As driver age increased, more drivers sustained injuries. There was 1 fatality; this 

occurred for an 82-year-old driver who died 3 weeks post-crash. In North Carolina, if a death occurs 

within 12 months of a crash, it is deemed a fatal injury crash.
55

Table 14. Injury Status of Vehicle Occupants and Pedestrians in Crashes Involving Pedal 

Misapplications, by Vehicle (North Carolina Crash Database Sample)

Injury Status

Road User Type

Pedal All

Misapplication 

Vehicle Other Vehicles Pedestrians

N % N % N % N %

Fatal injury (K) 1 0.03% 0 0.00% 0 0.00% 1 0.02%

Disabling injury (A) 5 0.15% 2 0.14% 3 6.52% 10 0.21%

Evident injury (B) 132 4.05% 33 2.30% 21 45.65% 186 3.93%

Possible injury (C) 347 10.65% 302 21.07% 19 41.30% 668 14.10%

No injury (O) 2,772 85.11% 1,096 76.48% 3 6.52% 3,871 81.74%

Total 3,257 100.00% 1433 100.00% 46 100.00% 4736 100.00%

The number of fatalities was missing from 10 news reports of media-reported pedal 

misapplication crashes. It may be inferred that for these 10, there were no fatalities, based on 

“newsworthiness” of deaths in crashes. Adding those 10 crashes to the 781 crashes reported to have 

no fatalities, pedal misapplication crashes resulted in no fatalities in 791 of 899 cases (88%). The 

remaining 108 pedal misapplication crashes resulted in 140 fatalities. These numbers include all 

people killed as a result of the crashes. In 94 crashes, one person was killed. In 10 crashes, two 

people were killed. One crash resulted in the death of three people, another in the death of four 

people, another in the death of nine people, and one crash reported in the media resulted in the death 

of 10 people. 

The number of injuries was not mentioned in 78 of the news reports. Researchers removed

these 78 crashes from the injury analyses, rather than assume they involved no injuries. Of the 

remaining 821 crashes, 387 (47%) involved no injuries, while 434 (53%) involved injuries. The 

total number of injuries reported in the articles describing these 434 crashes was 1,093. In the 

majority of injury crashes (53%), one person was injured. In 19% of the crashes with injuries, two 

people were injured. In 11%, three people were injured. In the remaining 17% of the injury crashes, 

anywhere from four to 23 people were injured. One crash resulted in 60 people being injured. 

NMVCCS codes the “Maximum Known Police Reported Injury in Crash,” which includes 

injuries in all vehicles involved in a crash. None of the pedal misapplication crashes recorded in 

NMVCCS resulted in a fatality. Four crashes (13%) resulted in incapacitating injury,

16 5 crashes 

(16%) resulted in non-incapacitating injuries, 11 crashes (36%) resulted in possible injury, and 9 

crashes (29%) resulted in no injuries. Injury severity was missing for 2 of the 31 crashes. Table 15

presents the unweighted and weighted frequencies and percentages of crashes by maximum known 

police reported injury. 

 16 Any injury, other than a fatal injury, which prevents the injured person from walking, driving or normally continuing 

the activities he was capable of performing before the injury occurred is labeled “incapacitating.”
56

Table 15. Pedal Misapplication Crashes, by Maximum Known Police Reported Injury for 

Each Crash (Unweighted and Weighted NMVCCS Data)

Highest Injury Severity in Crash

Unweighted Weighted

Frequency Percent Frequency Percent

O – No injury 9 29 1,535 31.1

C – Possible injury 11 35.5 1,711 34.7

B – Non-incapacitating injury 5 16.1 996 20.2

A – Incapacitating injury 4 12.9 519 10.5

Unknown if injured 1 3.2 167 3.4

No police accident report obtained 1 3.2 ---- -----

Total 31 100 4,928 100

Property Damage

To indicate property damage, reporting officers in North Carolina enter property (other than 

motor vehicles and their loads) that was damaged, identify the owner, and enter an estimate of the 

dollar damage. Damage to signs, buildings, mailboxes, fences, etc., are included in the estimate.

A summary of the officer-estimated damages for 2,396 crashes is presented in Table 16.

Property damage estimates ranged from $25 to $204,000, averaging $7,547. Sixty percent of the 

crashes resulted in additional damages of $5,000 or less; 23% resulted in damages between $5,001 

and $10,000; and 17% over $10,000. To reiterate, these estimates were provided by law 

enforcement officers, not insurance adjustors.

DRIVER REHABILITATION SPECIALIST PANEL

Driver rehabilitation specialists (DRS) are specially trained professionals who evaluate their 

clients’ ability to operate a vehicle safely by conducting on-road tests in vehicles equipped with a 

dual braking system. The DRS rides as a passenger in the test vehicle, and may apply the passengerside brake and take control of the steering, if necessary to prevent a collision or other unsafe 

maneuver made by their clients.

Pedal Application Error Definition

Early in the discussion, panelists agreed that a pedal misapplication need not result in a fullthrottle or high-power acceleration (as in the definition of sudden unintended acceleration applied in 

the 1980’s), in order for it to be considered a pedal misapplication. The pedal application errors 

observed by the DRSs occurred at low as well as at high speeds, and none of the DRSs allowed the 

error to continue to full throttle, if a driver failed to correct a pedal misapplication. To frame this

discussion, DRSs defined a pedal application error as unintentionally pressing the gas pedal instead 

of the brake pedal, at any speed, with or without subsequent correction by the driver. 

As revealed in the panel discussion, DRSs have observed the following pedal misapplication 

behaviors: (1) drivers with a wandering foot (termed submovements in the literature) moving 
57

between the gas and the brake pedal because they are not sure which pedal to press or where their 

foot is; (2) the driver who makes a pedal application error but corrects it; and (3) the person who 

makes a pedal application error and can’t recover from it (either at low speed or high speed). They 

emphasized that pedal misapplications occur along a spectrum, with all levels potentially 

devastating (whether low-speed or high-speed). The spectrum includes low-speed corrected errors, 

low-speed sustained errors, high-speed corrected errors, and high-speed sustained errors. Sustained 

full-throttle acceleration ending in a crash is the most extreme outcome.

Table 16. Pedal Misapplication Crashes by Property Damage Estimates (North 

Carolina Crash Database Sample)

Additional Property Damage Number Percent

Less than $500 37 2%

$500 to $1,000 122 5%

$1,001 to $2,000 411 17%

$2,001 to $3,000 389 16%

$3,001 to $4,000 252 11%

$4,001 to $5,000 211 9%

$5,001 to $6,000 180 8%

$6,001 to $7,000 137 6%

$7,001 to $8,000 99 4%

$8,001 to $9,000 66 3%

$9,001 to $10,000 59 2%

$10,001 to $15,000 186 8%

$15,001 to $20,000 65 3%

$20,001 to $25,000 72 3%

$25,001 to $30,000 22 1%

$30,001 to $35,000 22 1%

$35,001 to $40,000 7 0%

$40,001 to $45,000 21 1%

$45,001 to $50,000 1 0%

$50,001 to $60,000 12 1%

$60,001 to $70,000 8 0%

$70,001 to $80,000 5 0%

$80,001 to $100,000 2 0%

$100,001 to $150,000 8 0%

Greater than $150,000 2 0%

Total 2,396 100%

Prevalence of Pedal Misapplications

The DRSs stated they do not see many pedal application errors occurring on-road, which is 

likely the result of pre-screening clients in the clinic. DRSs generally reported not allowing clients 

with sensory problems in their feet to proceed to on-road evaluations; instead, CDRSs evaluated 

these drivers for their ability to use hand controls. In fact, if a client fails any critical part of the 

clinical physical or cognitive assessment, the DRSs may not take them on the road.
58

The 14 participating DRSs who perform on-road evaluations estimated that, collectively, 

they have seen a total of 380 pedal application errors committed by their clients on the road in the 

247 aggregate years of practice represented by this group. This is an average of 1.5 pedal 

misapplications observed per year, per DRS. Estimates ranged from 5 on-road pedal application 

errors observed by a DRS with 14 years of experience to 75 on-road pedal application errors

observed by a DRS with 20 years of experience. None of the observed pedal misapplications 

resulted in a crash. The DRSs indicated that the majority of the pedal application errors are 

corrected by their clients, but there have been instances when the DRSs have intervened, using the 

instructor brake.

Estimates of pedal misapplications in client population were higher if they include pedal 

application errors observed in the clinic on the brake reaction-time tester. DRS estimates of 

observed pedal application errors in the clinic ranged from 11 to 20 per year, per DRS. 

The DRSs cautioned that the population of drivers they observe on-road is atypical of the 

general population, because the clinical pre-screening assessments rule out on-road evaluations for 

drivers with sensory problems in their feet and those with cognitive impairments more severe than 

those diagnosed as “mild.” The incidence of sensory and cognitive impairment is likely to be higher 

among the general population, which includes those who have impairments that haven’t been 

diagnosed, and/or haven’t been evaluated for their ability to drive safely.

Characteristics of Drivers Who Make Pedal Application Errors

Driver Experience

The DRSs reported observing both novice and experienced drivers making pedal application 

errors. DRSs commented there are potentially different causes of pedal misapplications for younger 

(new) versus experienced (older) drivers.

Panelists cautioned that the inexperienced driver group includes new drivers as well as 

drivers who haven’t driven much in the past. Older does not always connote experienced. For 

example, a number of older women are not experienced drivers. Some have had very little 

experience because their husbands were the primary drivers; many have only resumed driving 

following the death of their husbands. 

Drivers With Sensory Impairments (Lower Limb)

There was consensus among the DRSs that peripheral neuropathy is of great concern as a 

potential cause of pedal application errors. DRSs indicated that over the past 10 years, larger 

percentages of their referred drivers have reported having trouble feeling their pedals. This includes 

people with knee and hip replacements, chemotherapy, multiple sclerosis, and conditions resulting 

in foot drop,

17 to name just a few. A panelist referenced an article by a psychiatrist in the practice of 

pain management and to the Neuropathy Association’s Web site (Donovan, 2012). These resources 

explain that 8 to 9% of Medicare recipients carry neuropathy as either a primary or secondary 

diagnosis—about 20 million people—yet neuropathy is one of the least recognized epidemics in the 

 17 Foot drop describes the inability to raise the front part of the foot due to weakness or paralysis of the muscles that lift 

the foot. It is a symptom of an underlying problem and is either temporary or permanent, depending on the cause. 

National Institute of Neurological Disorders and Stroke: http://www.ninds.nih.gov/disorders/foot_drop/foot_drop.htm
59

United States. The panelists agreed that many of their clients are unaware that they have a loss of 

sensation in their feet.

Many medical conditions can cause peripheral neuropathy, and physicians and occupational 

therapists (OTs) may not test for sensation in the feet of their patients. The DRSs compiled a list of 

conditions that can cause proprioceptive/sensory deficits that could contribute to a pedal 

misapplication (see Appendix E). They noted that chemotherapy exacerbates neuropathy.

Members of the panel said that physicians need to be educated about medical conditions that 

can cause peripheral neuropathy, they need to test their patients for it, and they need to be prepared

to discuss the implications of this condition for driving. Panelists recommended that physicians

refer their patients with loss of sensation in their feet to driver rehabilitation specialists who can 

evaluate them to see if they are candidates for driving with hand controls.

One DRS commented that the Santa Monica driver had spinal stenosis, which can cause 

peripheral neuropathy; but there was no mention in the NTSB report of whether he had problems 

feeling his feet. The DRS referenced an article by a physician, Dr. William. B. Donovan, who 

specializes in pain management, and who, himself, is a neuropathy patient (Donovan, 2008). After 

reading the story of the Santa Monica crash, Dr. Donovan wrote:

“I contacted several police officers who were familiar with similar cases. They were 

aware that such older drivers ‘confused’ the brake with the accelerator. What was 

surprising was that they all attributed the problem to cognitive, rather than sensory, 

confusion. When questioned further, they believed it would be unlikely for a police 

officer to be aware of the existence of peripheral neuropathy. Typically, police 

officers would pass off the case as being due to senility, pull the driver’s license, and 

submit it to the state licensing agency for re-evaluation.”

“I contacted the official responsible for reviewing all the traffic injury reports filed in 

one of the larger States for almost 30 years. Having suffered from diabetic 

neuropathy himself, he was familiar with impairment due to peripheral neuropathy. 

In reviewing tens of thousands of cases, he could recall not one report mentioning 

this possible cause.”

Drivers With Cognitive Impairments

Pedal application errors have been observed by DRSs among their client population that 

performed poorly in clinical tests with “executive function” tasks (e.g., clock drawing, Trail Making 

Test). The DRSs were familiar with the concept of sub-movements described in the literature 

review. Many indicated that they had observed such foot “wandering” in their cognitively impaired 

older clients.

In addition to sub-movements, one DRS noticed older clients pumping the gas and brake 

pedals more than their younger clients did. Another DRS pointed out that we really don’t know if 

sub-movements are a negative thing; a study (Cantin et al., 2004) indicated that older drivers made 

more sub-movements than younger drivers, but no pedal misapplications occurred in that study.

However, the literature on target acquisition tasks found more errors in the older subject groups, 

who also showed longer movement times and more sub-movements. A DRS indicated that it might
60

not be negative to have sub-movements. Another indicated the need to understand the contribution of 

foot wandering/sub-movements to pedal misapplication, to determine what predicts errors and what is 

normal. 

Panelists reported that another cognitively impaired group that makes pedal misapplications 

is young drivers with autism spectrum disorders (ASD), including Asperger’s syndrome and highfunctioning teens with autism, attention-deficit disorder (ADD), and attention deficit hyperactivity 

disorder (ADHD). Several DRSs indicated that there are many such drivers coming of driving age 

who need to be taught differently and require more practice than is available in traditional driver 

education or parent-taught driving. This group (ADD, ADHD and ASD) may slip through the DMV 

screening cracks because their disabilities are not always visible. Distraction could cause pedal 

misapplications in the group of young drivers with ADD and ADHD. Adolescents with autism are 

motorically challenged, so could be at increased risk of pedal application errors. Those with nonverbal learning disabilities might also be more likely to confuse the gas and brake, according to the 

DRSs. 

A DRS working in Washington, DC, said that driver license examiners in DC, Maryland, 

and Virginia do not allow clients to drive with both feet; nor do they allow anyone to drive with foot 

pedals who uses a lower extremity prosthesis, an ankle-foot orthosis (AFO), or has any sensory loss 

in their legs (proprioception or fine touch). Consequently, the population he assesses on the road 

exhibits very few pedal misapplications. Due to the DMV regulations, clients with the specified 

lower leg conditions either agree to learn to drive with hand controls or they give up their privilege

to drive. Anyone who is evaluated at this facility and diagnosed with a cognitive limitation (brain 

injury, Alzheimer’s, multiple sclerosis, stroke) must return for a second on-road assessment and 

perform well two times in a row, before being cleared to drive. The pedal application errors this 

DRS has observed were made by drivers learning how to use adaptive equipment, and novice 

drivers with cerebral palsy.

Drivers Using Adaptive Equipment

Several DRSs reported having observed pedal misapplications among their clients while 

they were learning to use adaptive equipment. One DRS who conducts training with a left-foot 

accelerator and hand controls reported that drivers have been convinced they are on the brake when

they are flooring the accelerator; while she had her foot on the instructor’s brake telling the driver to 

let off the gas the driver would still be flooring the accelerator. In her practice, this typically occurs 

with the more borderline cognitively impaired clients being trained to use adaptive equipment. 

One DRS commented that she does not think that people who are properly assessed, 

properly trained, and have adaptive equipment properly installed are any more likely to have pedal 

misapplication crashes than the general public. DRSs agreed that their clients must show mastery in 

using the adaptive equipment before they are released to drive independently.

Female Drivers/Drivers of Short Stature

The DRSs commented that women are smaller and their “fit” in the driver’s seat is often 

poor. Many sit with their hips stretched forward, which can cause leg cramps as well as temporary 

loss of sensation in their foot and leg. Their vehicles (as opposed to a medical condition) are

causing a problem: they are not positioned properly in their seats, and if their legs are cramping or 
61

falling asleep, they probably cannot feel the pedals. The panelists who conduct CarFit evaluations18

said many women do not fit well in vehicles with large seat pans, and older women often do not

know how to use the features in their cars (power seat adjustments) to make the fit better. The

DRSs have observed women at these events sitting too far away from the steering wheel, sitting too 

low, reaching for controls, and stretching with their toes.

Short females with small feet need to pick their foot up to move it from the gas to the brake, 

whereas taller people (or those with bigger feet) can rock their foot (pivot) between the gas and the 

brake, which provides more control, according to a DRS panelist. Picking up the foot to move it 

from pedal to pedal also causes more variability in movement than pivoting the foot.

Drivers Who Use Both Feet

DRSs commented that clients who began driving with both feet late in their driving careers 

have been more likely to make pedal application errors; both-footed driving does not seem to be a 

problem for those who have driven with both feet all their lives. The DRSs said that clients who 

start this practice late in life end up pressing both pedals at the same time. Their feet get tired 

because keeping the foot from pressing the gas pedal requires dorsiflexion. Their feet end up putting 

more pressure on the gas pedal than they realize, and if their hearing is impaired, they may not hear 

the engine revving. If they wait at a traffic light with one foot on the brake and the other on the gas

(heavy, because their foot is tired), when the light turns green, they take their foot off the brake and 

they unintentionally accelerate and hit the car in front of them.

DRSs indicate this behavior is prevalent in parking lots, particularly among older drivers 

who are more cognitively impaired. DRSs notice an evolution from one- to two-footed driving

among this population. Drivers start with their left foot on the brake; they shift the car into reverse, 

and then they put their right foot back on the accelerator and do two-footed driving while backing. 

They also do it when entering the parking spot, and when starting from a stopped position in the 

parking lot.

 

18 CarFit is an educational program created by the American Society on Aging and developed in collaboration with 

AAA (American Automobile Association), AARP, and the American Occupational Therapy Association designed 

to help older drivers find out how well they currently fit their personal vehicle. The program reviews 12 key areas, 

such as knowing how to properly adjust one's mirrors to minimize blind spots; good foot positioning on the gas and 

brake pedals to avoid leg fatigue and slowed reaction times; and learning the dangers of sitting closer than 10 

inches to the steering wheel/airbag.
62

Summary of Driver Characteristics

The DRSs indicated three general populations of drivers who make pedal application errors: 

(1) those with sensory defects in their feet; (2) those with cognitive limitations; and (3) those with 

no specific medical conditions or functional impairments, but who are influenced by situational 

factors that overwhelm everything else (inexperience; misfit in the vehicle; new vehicle;

distraction).

Situational Factors That May Contribute to Pedal Misapplications

Driving a New or Different Vehicle

The DRS panelists, particularly those who conduct CarFit evaluations, indicated that when 

drivers purchase new vehicles there typically is only a superficial orientation to the car by 

salespeople. There are features in new cars that operate differently from older cars, or were not even 

present in their older vehicles. For example, many drivers of small stature do not realize they have 

power seats in their new vehicles that can move forward and move higher.

People often do not understand how certain features in their cars work. Automation to 

increase fuel efficiency may make the car act strangely. It may not accelerate as expected going 

uphill with the air conditioner on, or the engine may rev for no apparent reason, and people think 

something is wrong with the car. Car dealers do not explain to customers that the car will normally

rev in some situations, and at other times may not speed up immediately when the accelerator is 

pressed, because the computer program that controls the vehicle enhances fuel efficiency and prevents 

over-torquing the engine. It confuses drivers when the car does not respond as they expect, and this 

could contribute to a pedal application error. 

Drivers in unfamiliar vehicles may be more likely to make a pedal application error. One 

DRS evaluated and trained a driver in a sedan, where the driver’s legs were positioned out in front 

of him, and then took him on-road in a van, where he had to pick up his foot to brake, instead of 

pivoting, because the leg positioning was different. The combination of a different seating posture

and leg position resulted in a pedal misapplication (pressing the gas pedal on an approach to a stop 

sign) requiring DRS intervention. The DRS indicated that it was all she could do to keep the car 

from running into a house and concluded that you cannot always make a valid judgment of 

someone’s capabilities in one type of vehicle based on their performance in another type.

Other DRSs noted that the pedal application errors that NTSB investigated involved school 

bus drivers who have a lot of experience as drivers, but (1) the pedal configurations in buses are 

different than they are in cars, and (2) some of the drivers had recently switched buses. So, even 

between similar vehicles, the pedal configuration could differ.

Drivers who do not adjust the seats, mirrors, etc., to suit them when they drive vehicles 

shared with other drivers also may be more at risk of making a pedal misapplication. The DRSs 

stated that this might be a cohort effect: older women may be more reluctant than younger women 

to change their husband’s settings.
63

Driver Seating Position

The panelists stated that large seat pans do not work well for smaller drivers. Small-statured 

drivers sit with their hips stretched forward and may need to stretch with their toes to reach the 

pedals. This causes leg cramps and may cause their feet to fall asleep. It is stressful for people when 

they cannot position themselves comfortably in their vehicle. Some women, especially, sit too far 

away from the steering wheel, sit too low, and need to reach (with their arms and their legs) for 

everything. Many do not know how to adjust their side mirrors and have no idea that they have a power 

seat that adjusts seating position in multiple ways.

Cars with bench seats allow people to be “out of position” with respect to foot placement. 

People who do not wear seat belts may also sit out of position. Some people sit off- center because 

their seatbelt catches them; they shift it to keep it off their neck, which may move them out of position.

Using cruise control can also cause someone to be “out of position.” A DRS explained that 

the normal foot positioning on the highway without using cruise control is on the gas, so that’s the 

point of reference when it is time to move your foot to brake. In cruise control mode, a driver’s foot 

could be anywhere, so is out of position. The DRSs reported that older people or drivers with 

multiple sclerosis who have difficulty moving between the gas and brake pedal use cruise control 

like a hand control to drive in city environments.

Drivers who know they are out of position are also at risk. One DRS gave this example: If you 

are an older driver and your daughter, who really does not want you to drive much anyway, is sitting 

beside you, you feel nervous and stressed that she is watching everything you are doing. You do not

want to acknowledge your need to reposition; you just want to be natural and get in and drive.

The problem of person-vehicle fit addresses the onset of a pedal application error. Not 

realizing that you are out of position and thinking your foot is on the brake when it is on the gas 

explains not correcting the behavior. DRSs pointed to the NTSB’s findings that the Santa Monica 

Farmer’s Market driver was likely out of position in the driver’s seat after sliding across the seat to 

deposit a letter in a mailbox on the curb, prior to the pedal misapplication crash sequence. 

Distracted Drivers and Unexpected Events

Distractions inside or outside of the vehicle can contribute to pedal application errors. A 

DRS gave the example of an older woman who performed very well over the entire hour of her first 

lesson with adaptive equipment (left foot gas pedal), until she pulled into the rehab center parking 

lot, and saw her grandchildren jumping up and down and being excited about “grandma driving.”

When she was told to brake, she mistakenly accelerated. 

Something unexpected happening in the driving environment can trigger a pedal application 

error. An event may be unexpected because a driver is distracted, perhaps by engaging in some kind 

of non-driving activity. Then the traffic light changes, or a car pulls out of a driveway, or another 

aspect of the traffic situation surprises them, and the result is a pedal misapplication.
64

Pedal Misapplication Location

Parking Lots

DRSs training clients to use adaptive equipment provided additional insight about the 

location of pedal misapplications, as evidenced by the following comment:

“Any of us who’ve trained people on adaptive equipment know that before I let 

somebody go with a left-foot accelerator or hand controls, I am spending so much 

time in parking lots, because if there’s going to be an error between gas and brake 

with any of that adaptive equipment, it’s going to happen in a parking lot. That’s 

where the majority of my time is spent at the end of my training with adaptive 

equipment. I’ve got to see 20 good parks and back-ups in different congested 

parking lots, going in and out before I’m ever going to let that person go. That’s 

where it’s going to happen; it’s going to happen right there in a parking lot.”

Similarly, several DRSs said that their final on-road test to ensure that the driver is safe, is the local 

discount store parking lot, because everyone’s lot is “equally crazy” and if a driver is going to 

exhibit a problem that has not shown up in the lower-level, open-road portion of a test, the parking 

lot is where it is going to occur.

Twelve of the 14 DRSs who conduct on-road assessments with clients indicated that the 

majority of the pedal application errors they observed occurred in parking lots. The drivers being 

evaluated became nervous or anxious when they got close to other cars and there was little room to 

maneuver. Many foot movements are required in parking lots. Tasks (planning processes and foot 

movements) are compressed, so the demand for divided attention skills is increased. People need to 

look over their shoulders more frequently in parking lots and that puts them “out of position” which 

can lead to pedal application errors.

In reference to the media analysis and crash database report, the DRSs mentioned that pedal 

misapplication crashes may be more frequent in parking lots because there is less room to 

recover/correct a pedal application error, given the proximity of cars and other objects. The DRSs 

hypothesized that many more pedal misapplications may occur on-road than showed up in the 

media analysis, because drivers corrected, so they did not result in a crash. There is room for 

correction on-road that is not available in parking lots. In summary, panelists identified three 

reasons pedal misapplications occur more often in parking lots than on-the road: (1) parking 

requires multiple pedal movements; (2) parking lots pose greater divided attention requirements; 

and (3) in the event of a pedal application error, there is less room for recovery.

Finally, several DRSs commented that parking lots are where drivers move from one- to 

two-footed driving, sometimes without realizing it. They press both pedals, and when they shift out 

of park and into drive or reverse and then take their foot off the brake, the car can accelerate like a 

sling shot. Panelists noted that this may happen when the driver is stopped in a parking lot, or when 

entering or leaving parking spots, with drivers using both feet. Panelists reported observing this in 

the older driver population, particularly among those with cognitive impairment.
65

On-Road

Only 2 of the 14 DRSs who conduct on-road assessments and training indicated that most of 

the pedal misapplications they had observed were on-road (as opposed to in parking lots). Examples 

were: during a right turn after stopping at a stop sign; in stop-and-go traffic; on the highway; and in 

cognitively taxing situations that require good divided attention skills. These included neighborhood 

streets with people and cars on the roadsides, and on a 40-mph roadway where the driver had to

respond quickly to traffic signal changes. Other on-road situations where pedal application errors 

occurred included complicated maneuvers that require the driver to change directions, such as 3-

point turns.

One of these DRSs may have a more fit clientele than the others (i.e., more typical of the 

general population); included among her clients were research participants who were not medical 

referrals for driving evaluations. This DRS indicated that 75% of the pedal application errors she 

had observed occurred on-road (and not in parking lots). The other DRS indicated that on-road

pedal application errors were most likely to occur when her clients were startled.

During the Final 30 Seconds of a Trip

Panelists noted that pedal application errors were more likely to occur during the final 30 

seconds of a driving evaluation. Either something distracted clients at the end of their drives, or they 

were relieved that the evaluation was over and did not feel the need to concentrate.

When asked whether this might be a consequence of fatigue, the DRSs said, no, it was more 

of a “let down” response; drivers just did not concentrate as hard at the end because the evaluation 

was “over.” Another DRS said she has observed 10 to 15% of her clients run the stop sign at the end 

of their evaluation. These clients performed well on the whole evaluation, until they got to the end.

It is the same phenomenon as when pedal application errors occur in the driveway and the garage, 

where drivers hit their houses. They “relax” from the driving task when they reach home, or at the 

end of their trip, and that is when a pedal misapplication occurs.

Possible Explanations for Why a Driver Doesn’t Correct a Pedal Misapplication

Cognitive Impairments

As one DRS said, “Regardless of what triggers the behavior, if the driver cannot correct the 

pedal application error there’s a cognitive reason.” Appendix F contains a list of cognitive 

impairments generated by the DRSs that may keep people from correcting a pedal misapplication, 

once one is made. Several are described in detail below.

A DRS stated that borderline cognitively impaired people may be startled when the car does 

not move as they think it should, then instead of making an appropriate correction to take their foot 

off the accelerator and apply the brake, they floor the accelerator. 

Anxiety decreases driving performance. One DRS described a driver with mild dementia 

who did fine the entire drive until she forgot the third destination she had planned at the start of the 

trip. She panicked when she did not know where she was, and made many critical driving errors.

Panic is an internal distraction. Another DRS indicated that seniors with dementia find it very 
66

stressful to recall a destination and remember how to get to it. This could easily contribute to pedal 

application errors.

One DRS described a pedal misapplication made by a client who did not perform well on 

the Trails B test in the clinic (indicating cognitive impairment). This driver was exiting a highway 

on a ramp with a red traffic light and three cars stopped ahead of him at the light. He began 

accelerating, and the DRS told him to slow down. He appeared not to hear her, and continued 

accelerating, appearing confused. He knew he was doing something wrong, but he could not fix it, 

and became anxious. His anxiety produced more confusion, and continued acceleration. The DRS 

finally put the car in neutral and took control. 

Situationally Induced Cognitive Overload

Set shift impairment—i.e., inability to take the foot off the gas and put it on the brake, 

because the driver believes it already is on the brake, so pushes harder on the gas—could be 

considered a transient “cognitive impairment” in the normal (not cognitively impaired) population.

In a state of panic, a driver may not be able to recognize and fix a problem. Situationally induced 

overload results in temporary impairment; it is not chronic cognitive impairment.

Countermeasures

Panelists offered a variety of countermeasures, but noted that they should be matched to the 

population committing the error: drivers with sensory loss; drivers with cognitive impairments; and 

drivers without medical conditions who make pedal application errors as a result of situational 

factors. Some of the countermeasures are obvious, such as for the 8-year-olds who the media 

analysis identified: do not let children drive. Drivers who have sensory loss in their lower limbs 

should acquire and learn to use hand controls. For drivers who are cognitively intact, panelists 

recommended education about how to shift to neutral to stop an unintended acceleration event.

Other countermeasures are less obvious, like educational campaigns directed to physicians 

and law enforcement officers to increase awareness about medical conditions that can cause 

neuropathy, and about referring these drivers to driver rehabilitation specialists and the medical 

review units of the DMV so they can be evaluated for hand controls. Similarly, educational 

campaigns could raise public awareness of the risks of driving with medical and functional 

impairments. Countermeasures suggested by the panelists are described in detail below.

Educational Campaigns

Teach the Driving Public to Use Neutral. In a panic situation, some drivers freeze and resort 

to what they know (i.e., pumping or sustained activation of the pedal that they believe is the brake, 

but is actually the gas). Panelists stated that drivers need to overlearn solutions that they can 

implement if their car goes out of control. Specifically, drivers need to know that “neutral is their 

friend.” DRSs said that this should be obvious, but is not taught or practiced in driver education, 

and it is not in the parent/tutor guides and may not be in driver manuals. One DRS noted that 

shifting to neutral was not taught in any of five graduate-level courses she took in traffic safety, as 

part of the requirement for being a driving school instructor; she learned it in a CDRS preparation 

course. 
67

A concise message that pairs this solution to an unintended acceleration event could be 

made into a public service announcement (PSA) that is presented on radio and TV to affect the most 

people. People may think they will harm the transmission if they shift into neutral at full speed, but 

it will not. This solution will work for unintended acceleration caused by vehicle malfunctions or by 

pedal application errors, in situations where there is time to shift the vehicle into neutral before it 

hits something.

Not all panelists were convinced that drivers could disengage enough to shift to neutral in a 

panic situation. Many older adults experience diminished frontal lobe functioning, and the frontal 

lobe is not fully developed in younger drivers. Others were more hopeful that an educational 

campaign could result in an overlearned response. DRSs indicated that people who overlearn 

emergency responses are better able to react correctly in a panic situation. Front-seat passengers 

could shift the car into neutral for the driver, if the driver freezes. This underscores the importance 

of this training for everyone, including parents supervising or teaching teens how to drive.

Teach Physicians About the Risks of Peripheral Neuropathy for Driving, How to Test for It, 

and How to Refer Patients to Driver Rehabilitation Specialists. Physicians need to be aware of the 

potential effects of peripheral neuropathy on driving safety. Topics that should be included in the 

educational campaign include medical conditions that can cause peripheral neuropathy, how to test 

for loss of sensation, and alternatives to foot controls for people with neuropathy. Physicians need 

to know that they can refer drivers to driver rehabilitation specialists who can evaluate clients for 

hand controls as remediation. Many doctors think this referral role places them in the position of 

police officers, and they do not want to be responsible for taking a patient’s license away. Doctors 

need to understand that their referral to the DRS may help their patient receive additional medical 

services so they can function better.

A few DRSs noted that this type of information is already covered in the AMA’s

Physician’s Guide to Assessing and Counseling Older Drivers (Carr, Schwartzberg, Manning, &

Sempek, (2010), but others noted that some physicians have not read the AMA guide. There is an 

AMA information outreach effort, but only a minority of doctors are members of AMA; a majority 

have not received the information. Panelists recommended continuing outreach efforts for the 

NHTSA/AMA course to educate physicians about how to screen and counsel older drivers about 

physical and cognitive problems that can affect safe driving, and educating physicians about 

referring these drivers to driver rehabilitation specialists for remediation. 

Educate DMV Personnel About Hand Controls for Drivers With Peripheral Neuropathy.

Along with physicians, DMV staff members need to be educated about hand controls for people 

with peripheral neuropathy. If a driver has been switched to hand controls by a DRS and goes to a 

DMV for licensing, the DMV needs to understand why the car has been equipped with hand 

controls for this person. A DRS said she trained to use hand controls, but the DMV said the driver 

did not need them. The client had to explain to the DMV license examiner that she could not use her 

pedals.

Educate Occupational Therapists to Test for Loss of Sensation in the Feet. Panel participants 

held an occupational therapy (OT) credential in addition to their CDRS credential. They noted that 

unless OTs are CDRSs, they do not routinely test for loss of sensation in the lower extremities. The 

panelists commented that OTs generally focus on clients’ arms and PTs (physical therapists) on the 

legs. PTs routinely test for foot sensation but typically OTs do not.
68

Continue Efforts to Educate Police About How to Identify and Refer At-Risk Older Drivers.

DRSs stated that law enforcement officers need to know how to refer drivers to DMV Medical 

Review Units for evaluation and remediation of medical and age-related functional impairments.

Several DRSs stated that NHTSA has a course addressing this issue, but it should have more 

exposure. One CDRS who teaches at the police academy in her State indicated that officers avoid

referring older drivers.

Teach the General Public About the Dangers of Driving While Impaired. A public education 

campaign is needed to raise awareness about the dangers of driving with physical or mental 

impairments, regardless of whether they are caused by age-related functional impairments, medical 

conditions, or medication use. A similar social norming campaign was successful in reducing drunk 

driving (“friends don’t let friends drive drunk”) and increasing seat belt use (Click It or Ticket

campaigns). Panelists recommended that the public education campaign run parallel to the 

education campaigns for physicians and police. Targeting social norms makes it easier for 

physicians and police officers to refer drivers, to the extent a campaign is successful in changing 

public opinion about the issue of driving with functional or medical impairments.

DRSs suggested that pedal application errors happen more often than they are reported.

People back into poles in parking lots and do not report it to the insurance company, because they 

do not want their rates to increase. DRSs commented that it was important to educate not only the 

public, but physicians, and others who regularly work with older people, about the importance of 

minor fender benders as indicators of early dementia.

Other Components of Pedal Application Error Prevention That Could Be Incorporated in 

Media and Driver Education Campaigns. Panelists suggested incorporating the following elements 

into campaigns to promote safe driving and in other driver education efforts.

• Educate drivers about the importance of proper seating positioning—being out of position 

affects where drivers place their feet.

• Educate drivers about the importance of fully learning how to operate their cars, not just 

how to pass the test.

• Educate drivers about proper footwear for driving (e.g., no flip-flops).

• Educate drivers not to use cell phones when driving because this can cause a distraction that 

could lead to a pedal misapplication.

• Teach drivers that sometimes drivers are the cause of unintended accelerations, and if the car 

accelerates out of control, they should take their feet off all pedals, and then if the car 

continues to accelerate, shift into neutral.

Improvement of Traffic Records

There were two recommendations in this area:

• Add a field on the crash report to code whether a crash involves a pedal application error, so 

that such crashes can be more easily and accurately identified in future research. 

• Develop a checklist for law enforcement officers to use for gathering information about 

drivers in pedal misapplication crashes (e.g., medical conditions, medications, whether 

drivers use both feet to control the pedals, distractions, etc.). 
69

CASE STUDIES

Two types of case studies were undertaken in this research. First, researchers reviewed Iowa 

DMV reexamination data for general information about drivers’ fitness to drive based on their 

reexamination test performance. Second, the research team conducted one-on-one unstructured 

telephone discussions with North Carolina drivers involved in pedal misapplication crashes in 2008 

to uncover more detail about the crash circumstances than was provided in the crash narratives.

Interviewers asked drivers about potential contributors to their pedal misapplications, such as 

medical conditions and use of medications, driving experience, type of footwear, use of cruise 

control, and familiarity with the vehicle. The findings from the Iowa data exploration activity are 

presented first, followed by those uncovered in the North Carolina case study telephone discussions.

Case Study Investigation of Drivers Required to Undergo Reexamination After Involvement 

in a Pedal Misapplication Crash (Iowa)

Of the 349 pedal misapplication crash-involved drivers, 95 were required to undergo 

reexamination and 254 were not. As shown in Table 17 and Figure 6, the sample of reexamined 

drivers was older on average than the sample of drivers not reexamined. 

Table 17. Summary Statistics Describing Driver Age by Reexamination Requirement, for 

Iowa Drivers in Pedal Misapplication Crashes (n=349)

Driver Group Number Age Range Average Age Standard 

Deviation

Reexamined 95 17-98 80.5 11.3

Not Reexamined* 252 11-95 37.7 22.1

*Age and sex missing for 2 drivers

Figure 6. Age Distribution of Drivers With Reexamination Requirement Versus No 

Reexamination Requirement

0

2

4

6

8

10

12

14

16

18

20

22

24

1113151719212325272931333537394143454749515355575961636567697173757779818385878991939597

Driver Age

Number of Drivers

Drivers Reexamined

Drivers Not Reexamined
70

Across the sample of 349 drivers, 66% were female. The percentage reflects the earlier 

findings from the North Carolina crash analysis, the NMVCCS analysis, and the media analysis that 

females were overrepresented in pedal misapplication crashes. Within the sample of 95 reexamined 

drivers, 63% were female, and 67% of the 252 drivers not required to undergo reexamination were 

female.

Due to confidentiality requirements, the Iowa DMV could not provide data to describe 

medical conditions or functional impairments associated with the pedal misapplication crashes.

However, law enforcement officers use a field on the Iowa crash report form to code driver 

condition at the time of the crash into the one of the following categories: apparently normal; 

physical impairment; emotional (e.g., depressed, angry, disturbed); illness; asleep, fainted, fatigued; 

under the influence of alcohol/drugs/medications; other; or unknown. As shown in Table 18, the 

majority of drivers (85%) were coded as apparently normal. The narrative provided a description for 

only 2 drivers described as “other,” 1 driver was parking in a handicapped spot and another driver 

had a medical issue that was unspecified in the narrative. The researchers read through each of the 

349 crash narratives to uncover evidence of medical conditions, physical impairments, or cognitive 

impairments. Only 15 narratives contained such descriptions. Two drivers were described as having 

“medical issues” (no other detail was provided); 11 drivers were described as entering or leaving 

handicapped parking spaces (with one driver using both feet), 1 driver was “feeling ill;” and one 

driver was “fatigued from a run.”

Table 18. Reported Condition of Iowa Drivers Involved in Pedal Misapplication Crashes, by 

Reexamination Requirement. (Iowa Sample, n=349)

Driver Condition

(Coded by Law Enforcement Officer)

Reexamined Sample

Number (%)

Not Reexamined Sample

Number (%)

Apparently normal 70

(74%)

227

(90%)

Physical impairment 1

(1%)

1

(0.4%)

Emotional (e.g., depressed, angry, disturbed) 1

(1%)

4

(2%)

Illness 2

(2%)

1

(0.4%)

Asleep, fainted, fatigued, etc. 1

(1%)

2

(0.8%)

Under the influence of alcohol/drugs/medications 0 2

(.8%)

Other (explain in narrative) 16

(17%)

10

(4%)

Unknown 4

(4%)

6

(2%)

Total 95 253

License restrictions in effect, either at the time of the crash or following reevaluation, may

indicate deficits in certain functional abilities critical to safe driving. For example, drivers restricted 

to driving with corrective lenses or during daytime could reasonably be expected to have a visual 

impairment; those with prostheses or mechanical aids a physical impairment of the upper or lower 
71

limbs; those with outside mirror requirements a head/neck/upper body flexibility impairment; and 

those with speed, roadway, or geographic restrictions a cognitive impairment. 

Table 19 presents the number of drivers by restriction type and reexamination status. The 

number of restrictions is larger than the number of drivers because a driver may be restricted in 

multiple ways. Nearly half of the drivers not required to undergo reexamination were without 

restrictions, compared to only 15% of the reexamined sample. Across the full sample, the most 

prevalent restriction was corrective lenses. Not surprisingly, a higher prevalence of corrective lens 

restrictions was observed among the reexamination sample, due to the inclusion of a larger 

percentage of older drivers. Eight percent of the reexamined drivers had a daytime-only restriction; 

none of the non-reexamined drivers were restricted to daytime. Similarly, only drivers in the 

reexamination sample had speed and roadway type restrictions (albeit a small percentage). Outside 

mirror requirements were more prevalent in the reexamination sample. Seven drivers in the 

reexamination sample and 1 driver in the non-reexamination sample had restrictions on the back of 

their licenses, which may indicate a geographic restriction (may drive only within a specific radius 

from home, only on specified roads, or to specified destinations).

Table 19. Restriction Type by Reexamination Requirement for Iowa Drivers in Pedal 

Misapplication Crashes.

Restriction Type Reexamined Sample

(n=95)

Non-Reexamined Sample

(n=254)

Total

(n=349)

None 14

(15%)

115

(45%)

129

(37%)

Non-commercial operator permit 0 21

(8%)

21

(6%)

Commercial instruction permit 2

(2%) 0 2(0.6%)

Except class A & B bus 0 1

(0.4%)

1

(0.3%)

Corrective lenses 69

(73%)

96

(38%)

165

(47%)

Minor’s school license 0 3

(1%)

3

(0.9%)

Left outside mirror 21

(22%)

11

(4%)

32

(9%)

No driving when headlights are required 8

(8%) 0 8(2%)

Restrictions on the back of the card 7

(7%)

1

(0.4%)

8

(2%)

No interstate or freeway driving 2

(2%) 0 2(0.6%)

Maximum speed of 35 mph 4

(4%) 0 4(1%)

SR-22 or SR-23 insurance 1

(1%)

4

(2%)

5

(1%)

Medical report required at renewal 0 1

(0.4%)

1

(0.3%)

Left and right outside mirrors 2

(2%)

6

(2%)

8

(2%)

Intermediate license 0 17

(7%)

17

(5%)
72

The DMV provided “yes/no” level data indicating whether a medical report was required for 

the 95 drivers who were required to undergo reexamination; whether drivers passed the written, 

vision and road tests; and whether their licenses were suspended as a result of the reexamination.

The DMV also provided supplemental notes about drivers’ involvement in multiple crashes.

The first finding of interest was that 55 drivers received an “incapable” suspension. This 

occurs when a driver submits an unacceptable medical report or fails one of the DMV tests (written, 

vision, or driving). This suggests that these drivers, representing 16% of the sample of drivers (55 

of 349) involved in a crash due to a pedal application error, were medically or functionally 

impaired. The circumstances surrounding these 55 incapable suspensions denoting driver incapacity 

are described below.

Four of the 55 submitted an unacceptable medical report, resulting in license suspension.

These drivers were ages 68, 78, 80, and 85.Twelve drivers voluntarily surrendered their licenses; 

they were age 62 (2 drivers), 74, 80 (2 drivers), 86 (2 drivers), 89, 90, 91 (2 drivers), and 98.The 74-

year-old driver had been involved in 2 crashes in the year of the pedal misapplication crash. One of 

the 91-year-old drivers had 5 crashes in the 6-year-period prior to the pedal misapplication crash 

and had 3 reexaminations. Fourteen drivers failed to appear for reexamination tests, resulting in 

their license suspensions. Their ages were: 17, 60, 79 (2 drivers), 80 (3 drivers), 86 (3 drivers), 87 

(2 drivers), 91, and 92. Three of these drivers had 2 crashes (ages 17, 60, and 80). Twenty-four 

drivers had incapable suspensions because they failed one or more of the DMV tests, as follows: 7 

failed the drive test; 4 failed the vision test, 5 failed the written test; 3 failed the written and driving 

tests; 1 failed the vision and drive test; 1 failed the vision and written test; and 1 failed all three 

tests. Four of the drivers who failed one or more of the DMV tests were noted as having multiple 

crashes. The 97-year-old driver who failed the written test had 3 crashes and 2 reexaminations. An 

89-year-old driver who failed the written and drive tests was reexamined on two occasions. Another 

driver (age 84) who failed both the written and drive tests had numerous charged crashes and 2 

incapable license suspensions. One driver (age 70) had two crashes. Thus, prior crashes appear to be 

indicative of future pedal misapplication crashes.

Of the 40 drivers who underwent reexamination and did not receive an incapable 

suspension, only 1 was noted as having prior crashes—this 88-year-old driver had 3 crashes prior to 

the pedal misapplication crash. The DMV did not provide data about prior crashes for the 254 

drivers with pedal misapplication crashes who were not required to undergo reexamination.

One-On-One Unstructured Conversations with Drivers Involved in Pedal Misapplication 

Crashes (North Carolina)

Only 10 of the 226 potential case-study drivers identified from the North Carolina data set 

participated in the unstructured discussions. A brief summary of the pertinent findings is provided 

below.

Two case study participants were males (age 29 and 67) and 8 were females (age 39, 53, 62, 

63, 65, 73, 81, and 85). Five of the 10 drivers (both males and the three oldest females) indicated 

their crashes were the result of their own errors (either their foot slipped or they hit the wrong 

pedal). The remaining five drivers maintained that their vehicles must have had an equipment 

malfunction, because they believe they were pressing the brake; however, their cars continued to 

accelerate out of control.
73

None of the drivers was using cruise control, or felt rushed prior to the pedal misapplication.

Only one driver indicated she was startled prior to the crash; her vehicle surged forward 

unexpectedly, which scared her. Three drivers, who were looking to the sides prior to the crash,

may have experienced a rightward bias in their foot aim toward the brake, resulting in hitting the 

gas pedal. One of these drivers was looking at police activity at the side of the roadway, one at the 

cars parked on both sides of the narrow parking space he was entering, and one at a car backing out 

of the parking space she planned to turn left into. The driver who was looking at the law 

enforcement activity at the side of the road was momentarily distracted.

All case study participants indicated that their vehicles were comfortable to drive and that it 

was easy to reach the pedals and adjust the seating position. The vehicles involved in the crashes 

were as follows: 1996 Subaru Legacy, 2002 Ford Taurus, 1997 Jeep Grand Cherokee, Subaru 

Impreza (year unknown), 1994 Lexus LS 430, 2005 Chevrolet Cavalier, 1999 Toyota Camry, 1999 

Honda Civic, 2002 Toyota Camry LE, and a 2000 Chevrolet Silverado. The five vehicles believed 

by the case study participants to have experienced a vehicle malfunction were the Ford Taurus, Jeep 

Grand Cherokee, Lexus LS 430, Toyota Camry LE, and Toyota Camry.

None of the drivers reported using a prosthesis, or having a cast or splint on their leg or foot 

at the time of the crash. None reported having a handicap placard, or using adapted driving 

equipment. Only one of the 10 drivers had had surgery on their hips, knees, or ankles within the 5-

year period prior to their crash; this driver had back surgery 5 years prior to her pedal 

misapplication crash. Two of the 10 drivers stated they had diabetes, and were taking medication to 

control their blood sugar; but neither wore special diabetic shoes, and neither described any signs of 

peripheral neuropathy. Only one of the 10 drivers indicated having any symptoms of peripheral 

neuropathy; this driver stated she had burning sensations in her feet at night. Four drivers (all 

women) stated they were taking medication for a thyroid condition. Other reported medical 

conditions included high cholesterol (2 drivers), high blood pressure, bad nerves/panic attacks, prior 

brain tumor resulting in a single seizure (16 years earlier), arthritis, a heart condition, gout, cataract 

plus glaucoma, overactive bladder, and attention deficit disorder. One driver stated that she had a 

hammer toe. Case study drivers reported four specific potentially driver-impairing medications: 

Tramadol (an opiate analgesic), Carvedilol (a beta blocker), Lamictal (anti-seizure medication), and 

Oxybutynin (an antispasmodic). All four contain a warning about side effects that may impair 

thinking and reacting, and advise caution if driving or doing anything that requires alertness. Two of 

the four medications include an additional caution about driving because of side effects that may 

impair vision.

Eight of the 10 drivers stated they drive using only the right foot to control the accelerator 

and brake pedals. The two “2-footed” drivers who said they use the right foot for the accelerator and 

the left foot for the brake, were both female. These individuals were in the subset of drivers who 

indicated their crash was due to a vehicle malfunction. One of these drivers said she learned to drive 

with both feet and has been doing so her entire driving career. The other driver said she uses both 

feet when reversing her car.

Three of the female drivers reported wearing clogs at the time of their crash. Two of the 

three were in the subset of drivers who stated their vehicles malfunctioned. Another female 

indicated wearing low-heeled pumps; this driver also uses both feet to drive. Other footwear at the 

time of the crash included leather walking shoes, athletic shoes/sneakers (3 drivers), and Van’s 
74

(“skateboard shoes”). One driver did not recall the footwear at the time of the crash, but indicated 

usually wearing flat shoes or low heels when driving.

Both male drivers reported that they were 5 ft, 10 inches tall. Females reported the following 

heights: 5 ft; 5 ft, 1 in; 5 ft, 4 in; (2 drivers), 5 ft, 41⁄2 in; 5 ft, 51⁄2 in; 5 ft, 6 in; and 5 ft, 9 in. Driving 

experience ranged from 4 years to 67 years, with 6 of the 10 drivers reporting over 40 years of 

experience. Driving experience in the vehicle involved in the pedal misapplication crash ranged 

from 1 year to 12 years.

Although this sample of drivers in pedal misapplication crashes is too small to draw any

meaningful conclusions, the information provided by these drivers corroborates some of the 

findings from earlier tasks, while adding detail not available from any of the other sources.

MEDIA ANALYSIS OF PEDAL-RELATED VEHICLE EQUIPMENT MALFUNCTIONS

A complementary media analysis in this project uncovered 520 reports of crashes where the 

brakes failed, the accelerator stuck or was trapped by a floor mat, or the vehicle suddenly 

accelerated for some unknown reason. The principal investigator read each news report and 

eliminated 68 reports from analysis because of possible driver contributions. For example, reports 

were eliminated for the following reasons: (1) the report stated that the cause of the acceleration 

was “unknown and may have been due to driver or vehicle factors;” (2) witnesses stated the driver 

had been acting strangely prior to the crash; (3) the driver was arrested for driving under the 

influence of alcohol or appeared drunk; (4) the driver was reportedly taking potentially driverimpairing medications or had symptoms of cognitively-impairing medical condition (e.g., taking 

opiate analgesics or having hallucinations); or (5) the driver was performing stunt-driving 

maneuvers.

The resulting analysis set included 452 crashes. These 452 crashes were divided into two 

groups: 170 crashes where the news report indicated that police or other independent investigation 

corroborated a driver’s assertion that a vehicle malfunction caused the crash (termed “othercorroborated”); and 282 crashes where the driver stated that the vehicle malfunctioned, and there 

was no further information confirming or denying the cause (termed “self-report-only”). Given 

questions about the reliability of the self-report-only data that may reasonably be expected, we 

present crash characteristics separately for each analysis group.

Another important distinction among these data relates to the type of equipment 

malfunction. As noted above, different equipment problems can lead to a “pedal-related” crash.

Table 20 shows the percentages of crashes in the present analysis set attributed in media reports to a 

stuck or jammed accelerator (without mention of any floor mat issues); to instances where a floor 

mat was pressing on the accelerator; to instances of brake failure; and to sudden acceleration events 

where none of the other problems listed above was mentioned. 

As shown, overall stuck accelerators accounted for approximately two-thirds of the crashes 

(64%) and failed brakes for approximately one-third (32%). Sudden acceleration events and floor 

mats pressing on the accelerator pedal accounted for just 3% and 2% of the news-reported crashes 

involving equipment malfunction, respectively. 
75

Table 20 also reveals differences that emerged between analysis groups in the reasons for 

their pedal-related crashes. Forty-six percent of crashes for the other-corroborated (OC) equipment 

malfunction group resulted from stuck accelerators, compared to 74% of the crashes for the selfreport-only (SRO) group. Brake failure accounted for approximately half (49%) of the crashes in 

the OC group, but only 21% in the SRO group.

Table 20. Media-Reported Equipment Malfunction Crashes by Malfunction Type and 

Analysis Group.

Equipment Malfunction Type

Analysis Group Total Other-Corroborated Self-Report Only

Number Percent Number Percent Number Percent

Stuck Accelerator 79 46% 209 74% 288 64%

Sudden Acceleration 1 1% 11 4% 12 3%

Floor Mat Pressing Accelerator 7 4% 2 1% 9 2%

Brakes Failed 83 49% 60 21% 143 32%

Total 170 100% 282 100% 452 100%

Driver Age

Driver age was provided in 126 of the crashes for the OC group and in 194 of the SRO 

group vehicle malfunction crashes. Table 21 shows descriptive statistics comparing driver age for 

these analysis groups. On average, drivers in the SRO group were 9 years older than drivers in the 

OC group.

Table 21. Driver Age by Analysis Group.

Analysis Group Number Age

Range

Mean

Age

Standard 

Deviation Age

Median

Age

Other-Corroborated 126 16 - 100 46 21 44

Self-Report-Only 194 15 - 92 55 23 56

Total 320 15 - 100 51.5 22.6 51

Figure 7 displays the complete distribution of drivers with equipment-related malfunction 

crashes by driver age and analysis group. Figure 8 sorts these data into 5-year age groupings.

In both analysis groups, drivers younger than 20 accounted for high proportions of 

equipment malfunction related crashes (10 to 11%). This trend continued for drivers 20-24 in the 

OC group. The proportion of crash-involved drivers in both analysis groups leveled out from 25 to 

39 at 4% to 5%. The proportion of OC group drivers spiked to 14% in the 40 to 44 age group while 

the proportion in the SRO group remained constant at 4%. The percentage in the OC group 

remained high between ages 45 and 49 (11%) compared to the SRO group (5%).The SRO group 

spiked at age 50 to 54 (9%), dropped back to 5% up to age 59, and then showed a gradual increase 

with increasing age, with the highest proportion among drivers 75 to 79 (almost 12%). The OC 

group, in comparison, had less than 2% of equipment malfunction crash involved drivers 75 to 79.

In general, the OC group had higher percentages of equipment malfunction crash involved drivers 

up to age 49 while the SRO group had higher percentages for drivers 50 and older.
76

0%

2%

4%

6%

8%

10%

12%

14%

16%

<20 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90-94 95-100

Driver Age Group

Percent of Drivers in Equipment 

Malfunction-Related Crashes

Other Corroborated (Percent)

Self-Reported (Percent)

Figure 8. Percentage of Drivers in Equipment-Related Crashes Reported by the Media (n=452) 

in 2000-2010, by 5-Year Age Groupings and Analysis Group

0

1

2

3

4

5

6

7

8

9

15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47 49 51 53 55 57 59 61 63 65 67 69 71 73 75 77 79 81 83 85 87 89 91 93 95 97 99

Driver Age

Number of Drivers with Equipment 

Malfunction-Related Crashes

Other Corroborated

0

1

2

3

4

5

6

7

8

15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47 49 51 53 55 57 59 61 63 65 67 69 71 73 75 77 79 81 83 85 87 89 91 93 95 97 99

Driver Age

Number of Drivers with Equipment 

Malfunction-Related Crashes

Self-Reported

Figure 7. Frequency Distribution by Driver Age and Analysis Group.
77

Because pedal misapplication crashes are often blamed on stuck accelerators, we examined 

the age distribution of drivers in the stuck accelerator equipment malfunction crashes, then 

compared it to the age distribution in pedal misapplication crashes uncovered in the earlier media 

analysis. Figure 9 presents the age distribution for the stuck accelerator equipment malfunction 

crashes by analysis group for the 207 incidents where the media report provided driver age. Figure 

10 collapses across analysis group, to compare the percentage of drivers by age group in mediareported stuck accelerator crashes to those in crashes involving pedal application errors reported in 

the media, for the same period (2000 to 2010). While not congruent, the patterns in the two types of 

media reports are broadly similar; to the extent that a bias toward reporting crashes involving older 

drivers with pedal misapplications was apparent in the earlier analyses, media reports of crashes due 

to this type of vehicle equipment malfunction may also be affected. 

Driver Sex

The news reports identified the sex of 158 of the OC group drivers and 266 of the SRO 

group drivers. Table 22 presents the percentage of males and females by analysis sample, and across 

the combined sample. These data show a reversal of the pattern identified in both the media analysis 

of pedal misapplication crashes and the North Carolina crash database analysis, and are more 

representative of National crash data (57% males and 43% females) (NHTSA, 2010).

Table 23 presents the breakdown by sex, for the subset of stuck accelerator malfunction 

crashes only. While the percentage of females in the OC group is higher than their proportion in all 

equipment malfunction crashes, females were still involved in stuck accelerator crashes at a lower 

rate than males (42% versus 58%). 

Table 22. Driver Sex by Analysis Group, for All Media-Reported Equipment Malfunction 

Crashes

Analysis Group Percent Male Percent Female

Other-Corroborated 61% 39%

Self-Reported 59% 41%

Total 60% 40%

Table 23. Driver Sex by Analysis Group, for Media-Reported Stuck Accelerator Malfunctions 

Only

Analysis Group Percent Male Percent Female

Other-Corroborated 54% 46%

Self-Reported 60% 40%

Total 58% 42%
78

0%

2%

4%

6%

8%

10%

12%

14%

<20 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90-94

Driver Age Group

Percent of Drivers in Stuck Accelerator 

Crashes

Other-Corroborated

Self-Report

Figure 9. Percentage of Drivers in Equipment-Related Crashes Reported by the Media 

(n=207) in 2000-2010, by 5-Year Age Groupings and Analysis Group, for Stuck 

Accelerator Crashes Only

0%

2%

4%

6%

8%

10%

12%

14%

16%

18%

<20 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85+

Driver Age Group

Percent of Drivers

Stuck Accelerator

Pedal Misapplication

Figure 10. Comparison of Media-Reported Equipment Malfunction Crashes (207 Stuck 

Accelerator Malfunctions Only) and Media-Reported Pedal Misapplication Crashes 

(n=683), by Driver Age Group
79

Further limiting the comparison to passenger cars with stuck accelerators, a greater 

percentage of crash-involved males than females self-report this problem, 58% to 42%, but for 

crashes that were corroborated by others the percentage of females slightly exceeded males (52% to 

48%). Additional analyses that examine vehicle type are presented below. 

Vehicle Type

Based on the information provided in the news reports we were able to code vehicle type 

(e.g., passenger car, SUV, tractor trailer) for 165 of the OC group equipment malfunction crashes 

and 275 of the SRO group crashes. The percentage of vehicle malfunctions by vehicle type and 

analysis group is shown in Table 24. The category of “other trucks” included fire truck, tow truck, 

and “truck” (undifferentiated). The “other” bus category included a shuttle bus.

The most prevalent vehicle type was passenger cars (55% of all vehicles), similar to the 

findings of the media analysis of pedal misapplication crashes (71%). This applied to both analysis 

groups. There were equal percentages of pickup trucks in both analysis groups (12%); however, 

this percentage was twice that found in the pedal application errors media analysis (6%). For 

crashes attributed to equipment malfunctions, the SRO group included higher percentages of SUVs 

and vans than the OC group; for comparison, the earlier media analysis of pedal misapplication 

crashes revealed percentages of these vehicle types similar to those of the SRO group in this 

analysis. However, the OC group included a higher percentage (21%) of heavy vehicles 

(school/commercial/other buses, tractor trailers, dump trucks, and other trucks) than the SRO group 

(10%); both of the present analysis groups included more heavy vehicles than were reported in the 

previous media scan of pedal misapplication crashes (2%). 

Table 24. Media-Reported Equipment Malfunction Crashes, by Vehicle Type and Analysis 

Group

Vehicle Type

Analysis Group

Other-Corroborated

Equipment Malfunctions

Self-Reported-Only 

Equipment Malfunctions Total

Passenger Car 93 (56%) 150 (55%) 243 (55%)

SUV 9 (5%) 40 (15%) 49 (11%)

Van 9 (5%) 21 (8%) 30 (7%)

Pickup Truck 20 (12%) 32 (12%) 52 (12%)

School Bus 3 (2%) 9 (3%) 12 (3%)

Commercial Bus 0 5 (2%) 5 (1%)

Tractor Trailer 15 (9%) 7 (2%) 22 (5%)

Dump Truck 13 (8%) 6 (2%) 19 (4%)

Other Truck 2 (1%) 4 (1%) 6 (1%)

Other Bus 1 (1%) 0 1 (<1%)

Ambulance 0 1 (<1%) 1 (<1%)

Total 165 (100%) 275 (100%) 440 (100%)
80

Vehicle Make, Model, and Year

Vehicle make was reported in 87 equipment malfunction crashes between 2000-2010 for the 

OC group and 161 crashes for the SRO group; vehicle model was reported in 56 equipment 

malfunction crashes for the OC group and 107 crashes for the SRO group; and vehicle year was 

reported in 65 equipment malfunction crashes for the OC group and 91 crashes for the SRO group.

In Table 25 shows only data for only the manufacturers of pedal-related crash-involved vehicles for 

both analysis groups; for comparison, the percentage of each make in the U.S. fleet (Polk Company, 

as of April 1, 2010) is also presented.

It appears that certain vehicle makes were overrepresented in media-reported equipment 

malfunction crashes for one or both analysis groups, in relation to their proportion of the overall 

fleet: Buick (for the OC group); Ford (both analysis groups); Jeep (SRO group); Mercury (SRO 

group); Oldsmobile (SRO group); Pontiac (OC group); and Volvo (both analysis groups).Other 

makes appear to be underrepresented based on their proportion of the current fleet—for example, 

Toyota, associated with 5% of crashes for the OC group and 6% of crashes for the SRO group.

It is important to note that vehicle make was reported in just slightly more than half of the 

news reports (248 of 452, or 55%), so the percentages reported in Table 25 may be an 

underrepresentation of particular vehicle makes in these equipment malfunction crashes.Vehicle 

make was reported in only 7 of the 66 heavy vehicle crashes linked to equipment malfunctions.

Table 26 presents the vehicle make percentages for just stuck accelerator equipment 

malfunction crashes, based on 44 OC group crashes and 128 SRO group crashes where vehicle 

make was included in the news articles. The same patterns are evident in these data as shown 

previously in Table 25, although percentages for the over-represented makes are slightly higher for 

the stuck accelerator crashes (e.g., Ford, Jeep, Lincoln, Mercury, and Pontiac).

Tables G-1 and G-2 in Appendix G show the make, model, and year (where reported) for the 

vehicles involved in equipment malfunction crashes, for the respective analysis groups.
81

Table 25. Media-Reported Equipment Malfunction Crashes by Vehicle Make and Analysis 

Group Versus Percentage of Vehicle Makes in Fleet

Vehicle Make

Other-Corroborated Self-Reported-Only Total Percent of 

Vehicle 

Fleet* Number Percent Number Percent Number Percent

Acura 0 0% 2 1% 2 1% 1.04%

BMW 0 0% 5 3% 5 2% 1.37%

Buick 6 7% 5 3% 11 4% 2.72%

Cadillac 2 2% 4 2% 6 2% 1.51%

Chevrolet 10 11% 23 14% 33 13% 15.40%

Chrysler 1 1% 1 1% 2 1% 2.53%

Dodge 3 3% 12 7% 15 6% 6.60%

Fiat 1 1% 0 0% 1 0% 0%

Ford 27 31% 34 21% 61 25% 16.64%

Freightliner 0 0% 1 1% 1 0% 0.10%

GMC 3 3% 4 2% 7 3% 2.95%

Honda 3 3% 5 3% 8 3% 7.15%

Hyundai 0 0% 1 1% 1 0% 1.71%

International 1 1% 0 0% 1 0%

Jaguar 1 1% 0 0% 1 0% 0.22%

Jeep 1 1% 10 6% 11 4% 2.67%

Keith-Huber 0 0% 1 1% 1 0%

Kia 1 1% 2 1% 3 1% 1.03%

Lexus 2 2% 0 0% 2 1% 1.36%

Lincoln 3 3% 4 2% 7 3% 1.09%

Mazda 1 1% 3 2% 4 2% 1.71%

Mercedes Benz 0 0% 3 2% 3 1% 1.36%

Mercury 2 2% 7 4% 9 4% 1.89%

Mitsubishi 1 1% 2 1% 3 1% 1.08%

Nissan 2 2% 2 1% 4 2% 4.74%

Oldsmobile 2 2% 9 6% 11 4% 1.55%

Plymouth 1 1% 1 1% 2 1% 0.66%

Pontiac 5 6% 6 4% 11 4% 3.06%

Saab 0 0% 1 1% 1 0% 0.23%

Toyota 4 5% 10 6% 14 6% 10.41%

Volkswagen 1 1% 0 0% 1 0% 1.52%

Volvo 3 3% 3 2% 6 2% 0.81%

* Data from The RL Polk Company: 233,871,380 vehicles in operation as ofApril 1, 2010.
82

Table 26. Media-Reported Equipment Malfunction Crashes for Stuck Accelerator Crashes 

Only, by Vehicle Make and Analysis Group Versus Percentage of Vehicle Makes in Fleet.

Vehicle Make Other-Corroborated Self-Reported-Only Total Percent of 

Number Percent Number Percent Number Percent Vehicle Fleet*

Acura 0 0% 1 1% 1 0.58% 1.04%

BMW 0 0% 3 2% 3 1.74% 1.37%

Buick 3 7% 1 1% 4 2.33% 2.72%

Cadillac 1 2% 4 3% 5 2.91% 1.51%

Chevrolet 5 11% 20 16% 25 14.53% 15.40%

Chrysler 1 2% 1 1% 2 1.16% 2.53%

Dodge 1 2% 11 9% 12 6.98% 6.60%

Fiat 0 0% 0 0% 0 0% 0%

Ford 16 36% 30 23% 46 26.74% 16.64%

Freightliner 0 0% 0 0% 0 0% 0.10%

GMC 1 2% 3 2% 4 2.33% 2.95%

Honda 1 2% 2 2% 3 1.74% 7.15%

Hyundai 0 0% 0 0% 0 0% 1.71%

International 0 0% 0 0% 0 0%

Jaguar 1 2% 0 0% 1 0.58% 0.22%

Jeep 1 2% 10 8% 11 6.40% 2.67%

Keith-Huber 0 0% 1 1% 1 0.58%

Kia 0 0% 2 2% 2 1.16% 1.03%

Lexus 0 0% 0 0% 0 0% 1.36%

Lincoln 3 7% 3 2% 6 3.49% 1.09%

Mazda 0 0% 1 1% 1 0.58% 1.71%

Mercedes Benz 0 0% 1 1% 1 0.58% 1.36%

Mercury 1 2% 7 5% 8 4.65% 1.89%

Mitsubishi 1 2% 2 2% 3 1.74% 1.08%

Nissan 0 0% 2 2% 2 1.16% 4.74%

Oldsmobile 1 2% 8 6% 9 5.23% 1.55%

Plymouth 0 0% 1 1% 1 0.58% 0.66%

Pontiac 3 7% 3 2% 6 3.49% 3.06%

Saab 0 0% 0 0% 0 0% 0.23%

Toyota 2 5% 8 6% 10 5.81% 10.41%

Volkswagen 1 2% 0 0% 1 0.58% 1.52%

Volvo 1 2% 3 2% 4 2.33% 0.81%

* Data from The R. L. Polk Company: 233,871,380 vehicles in operation as of April 1, 2010.
83

Next, analysts were able to code vehicle type for 440 of the media reports of crashes 

involving equipment malfunctions, based on the information provided in the news articles. Table 27

sorts the types of equipment malfunctions by analysis group and by vehicle type.

Table 27. Media-Reported Equipment Malfunction Crashes by Malfunction Type, Vehicle 

Type, and Analysis Group

Equipment 

Malfunction 

Type

Vehicle

Type

Other-Corroborated Self-Reported-Only Total

Number Percent Number Percent Number Percent

Stuck Accelerator

Commercial Bus 0 0% 2 1% 2 1%

Dump Truck 1 1% 0 0% 1 0%

Other Truck 0 0% 3 1% 3 1%

Passenger Car 54 70% 123 60% 177 63%

Pickup Truck 12 16% 27 13% 39 14%

School Bus 0 0% 2 1% 2 1%

SUV 7 9% 32 16% 39 14%

Van 3 4% 15 7% 18 6%

Total 77 100% 204 100% 281 100%

Sudden 

Acceleration

Passenger Car 1 100% 7 64% 8 67%

Pickup Truck 0 0% 2 18% 2 17%

SUV 0 0% 2 18% 2 17%

Total 1 100% 11 100% 12 100%

Floor Mat 

Pressing 

Accelerator

Passenger Car 6 86% 1 50% 7 78%

SUV 0 0% 1 50% 1 11%

Van 1 14% 0 0% 1 11%

Total 7 100% 2 100% 9 100%

Brakes Failed

Ambulance 0 0% 1 2% 1 1%

Commercial Bus 0 0% 3 5% 3 2%

Dump Truck 12 15% 6 10% 18 13%

Other Bus 1 1% 0 0% 1 1%

Other Truck 2 3% 1 2% 3 2%

Passenger Car 32 40% 19 33% 51 37%

Pickup Truck 8 10% 3 5% 11 8%

School Bus 3 4% 7 12% 10 7%

SUV 2 3% 5 9% 7 5%

Tractor Trailer 15 19% 7 12% 22 16%

Van 5 6% 6 10% 11 8%

Total 80 100% 58 100% 138 100%
84

As shown in Table 27, brake failure was the predominant equipment malfunction type 

associated with heavy vehicles, with tractor trailers accounting for 16% of the brake-failure crashes, 

dump trucks 13%, school buses 7%, commercial buses 2%, ambulances 1% and other trucks and 

buses 3%. In contrast, these heavy vehicles were never involved in the crashes involving floor mats 

pressing on the accelerator or in sudden acceleration event crashes, and in only 3% of the stuck 

accelerator crashes. Passenger cars were the vehicle type most often involved in equipment 

malfunction crashes; but were more prevalent in stuck accelerator crashes (63%), sudden 

acceleration event crashes (67%), and floor mat on accelerator crashes (78%) than in brake failure 

crashes (37%).

Time of Day

Table 28 presents crash time of day by analysis group for 361 news-reported crashes 

involving vehicle malfunctions, where time of day was reported. The proportion of crashes by each 

period was consistent across the OC and SRO analysis groups. The majority of the crashes (71%) 

occurred between 9 a.m. and 6 p.m.; this was also the case for the media-reported pedal 

misapplication crashes, where 77% occurred between 9 a.m. and 6 p.m. However, nearly twice the 

percentage of equipment malfunction crashes occurred between 6 and 9 p.m. (12% versus 7%), and 

three times as many occurred between midnight and 6 a.m. (9% versus 3%), compared to the pedal 

misapplication crashes.

Table 28. Media-Reported Equipment Malfunction Crashes, by Time of Day and Analysis 

Group.

Crash Time Other-Corroborated Self-Reported-Only Total

6 a.m. or earlier 5 (4%) 28 (12%) 33 (9%)

6 – 9 a.m. 13 (10%) 0 13 (4%)

9 a.m. – 12 p.m. 30 (23%) 57 (24%) 87 (24%)

12 – 3 p.m. 27 (21%) 50 (22%) 77 (21%)

3 – 6 p.m. 31 (24%) 62 (27%) 93 (26%)

6 – 9 p.m. 17 (13%) 25 (11%) 42 (12%)

9 p.m. – 12 a.m. 6 (5%) 10 (4%) 16 (4%)

Total 129 232 361

Crash Location

Table 29 presents the location of the equipment malfunction crashes by analysis group for 

all malfunction types, while Table 30 presents crash location for the subset of stuck accelerator 

malfunction crashes only. As shown in Table 29, slightly more than half (52%) of the malfunctions 

(all types) for the OC group occurred on the road (i.e., at non-intersection locations), while only 

38% of such crashes happened on-road for the SRO group. Conversely, higher percentages of 

crashes occurred in parking lots and driveways for the SRO group than for the OC group. 

Collapsing across analysis group and crash location, 40% of the pedal-related equipment 

malfunction crashes occurred in parking lots and driveways, while 60% occurred on-road (including 

intersections). This is a reversal of the findings for the media-reported pedal misapplication crashes, 

where 77% occurred in parking lots and driveways and only 23% occurred at roadway/intersection 

locations. 
85

Table 29. Media-Reported Equipment Malfunction Crashes by Location and Analysis Group 

(All Malfunction Types)

Crash Location OtherCorroborated Self-Reported-Only Total

Parking Lot 35 (21%) 89 (35%) 124 (30%)

Driveway 15 (9%) 28 (11%) 43 (10%)

On Road (Not at Intersection) 86 (52%) 97 (38%) 183 (44%)

Intersection 27 (16%) 40 (16%) 67 (16%)

Car Wash 1 (<1%) 0 1 (<1%)

Total 164 (100%) 254 (100%) 418 (100%)

Media-reported stuck accelerator crashes produced a different pattern. As shown in Table 

30, 55% of these crashes occurred in parking lots and driveways compared to 45% that occurred onroad (including at intersections). This pattern, which was stable across both analysis groups, is quite 

similar to that observed in the earlier analyses of pedal misapplication crashes, including results 

from the North Carolina crash database.

Table 30. Media-Reported Equipment Malfunction Crashes by Location and Analysis Group 

(Stuck Accelerator Malfunctions Only)

Crash Location OtherCorroborated Self-Reported-Only Total

Parking Lot 25 (33%) 79 (42%) 104 (40%)

Driveway 11 (15%) 27 (15%) 38 (15%)

On Road (Not at Intersection) 33 (44%) 62 (33%) 95 (36%)

Intersection 5 (7%) 18 (10%) 23 (9%)

Car Wash 1 (1%) 0 1 (<1%)

Total 75 186 261
86

DISCUSSION AND CONCLUSIONS

At the beginning of this project, the literature review uncovered two driving simulator 

studies describing the prevalence of crashes resulting from pedal misapplication, with mixed 

findings. In one study, drivers pressed the wrong pedal or both pedals simultaneously at a rate of 1 

per 4.8 hours of data collection, or once per 468 foot movements (Rogers & Weirwille, 1988).

There were only two instances during the 72 simulation hours where the driver pressed the 

accelerator instead of the brake, and both times, the driver recognized the error and corrected it. 

However, in another study using drivers 65 and older recruited from a driving evaluation clinic, 

one-third experienced unintended acceleration events, and 70% of these said they were unable to 

stop or slow the vehicle (Freund et al., 2008). These events were associated with a sudden change in 

the environment (e.g., an intrusion); with increasing age (drivers 84 and older were 6 times more 

likely to exhibit pedal application errors); and with impairments in executive function (impaired 

drivers showed error rates 10 times higher than drivers with normal executive functioning). 

Next, findings from the news media analysis suggested that crashes resulting from pedal 

misapplications, where the driver mistakes the accelerator pedal for the brake, occur 7 to 15 times 

each month somewhere in the United States This may be an underestimation, as not all crashes are 

reported in the news, and not all news reports are entered or maintained in the archives. Similarly, 

the findings from both the NMVCCS analysis and the North Carolina State Crash Database 

indicated a low prevalence of pedal misapplication crashes—less than 1% of all crashes—but these 

sources, too, are less than ideal. Because police crash reports do not include codes to indicate that a 

crash resulted from a pedal misapplication, researchers cannot query a field in any State or National 

database for crashes resulting from pedal application errors other than the narrative field. The 

narrative includes information about pedal misapplications only if the driver admits the error and

the investigating officer includes it in the crash description. However, while the prevalence 

estimates derived from this project are almost certainly biased toward underrepresentation, the pedal 

misapplication crashes that were identified and analyzed provided valuable information about the 

characteristics surrounding these events.

The DRSs participating in the expert panel reported observing, on average, 1.5 pedal 

misapplications per specialist, per year, in their client population during on-road evaluations. This 

low number may be the result of pre-screening clients in the clinic to eliminate those with lower 

limb sensory impairments from on-road testing. None of the pedal misapplications observed by 

DRSs resulted in a crash, and the majority were corrected by their clients.

The following discussion highlights areas of consistency—while also acknowledging 

significant disagreement—regarding the characteristics of pedal misapplication crashes as revealed 

by the literature review, media scan, and the NMVCCS and North Carolina crash database analyses.

DRS comments are included wherever pertinent. This section addresses variables where there was 

strong corroboration of findings across data sources: the distribution of sex of drivers in pedal 

misapplication crashes; the role of inattention/distraction in such crashes; the role of fatigue or 

impairment; drivers’ familiarity with the vehicle; driver position in the vehicle and its effect on foot 

movement accuracy; and situational factors that startle drivers and may lead to a crash. Two areas 

in which the present sources appeared to yield more disparate results—crash location and the age 

distribution of drivers in pedal misapplication crashes—are then highlighted.
87

This discussion ends with a focus on contrasts and similarities between the characteristics of 

crashes involving a pedal misapplication, versus crashes where some type of pedal-related vehicle 

equipment malfunction was implicated. Conclusions and priorities for continuing investigation 

follow.

Perhaps the closest agreement among sources was found for data describing the distribution 

of sex of drivers in pedal misapplication crashes. The North Carolina findings (male/female ratio = 

37/63 percent) corroborate the proportions in the NMVCCS analysis (male/female ratio = 35/65 

percent) and the media analysis (male/female ratio = 36/64 percent). It is apparent that females were

overrepresented in pedal misapplication crashes, compared to their representation in all crashes.

Driver inattention was the most frequently coded driver contributing circumstance in the 

North Carolina data. This broad indicator of driver error was noted for 44% of the crashes and was 

relatively equally prevalent across the age groupings of < 21, 21-35, 36-55, 56-75, and 76+. The 

more specific behavior driver distraction was coded as a contributing factor by police in 4% of the 

North Carolina pedal misapplication crashes, but was revealed in 7% of the crash narratives.

Drivers in the two older age groups (56-75 and 76+) were underrepresented in distraction-related

crashes compared to their representation in the sample, while drivers in the two youngest age 

groups (<21 and 21-35) were overrepresented. The most frequently noted distractions were looking 

away from the road, reaching for an object, passengers, and cell phones. Driver distraction was 

reported in 39% of the NMVCCS pedal misapplication crashes, and in 12% of the news media 

articles that mentioned a driver contributing factor. The potential for driver distraction to contribute 

to pedal misapplications was further underscored by DRS observations that when these errors

occurred during driving evaluations, it was commonly during the final 30 seconds, when clients 

relaxed their concentration on the driving task.

Driver fatigue factored in less than 1% of the North Carolina pedal misapplication crashes, 

10% of the NMVCCS crashes, and 2% of the news media reported crashes. Impairment due to 

alcohol also appeared to be a minor factor; this was suspected in less than 1% of the North Carolina

pedal misapplication crashes, 3% of the NMVCCS pedal misapplication crashes, and 8% of the 

news media reports of pedal misapplication crashes.

At the same time, functional impairment due to a medical condition or medication use was 

somewhat more likely to be implicated in pedal misapplication crashes. Approximately 7% of the 

North Carolina drivers involved in such crashes were so impaired. These included 35 drivers who 

were specifically described as having impairments in their lower limb functioning, either a loss of 

sensation, or reductions in strength or mobility; another 23 drivers were described as “handicapped” 

or parked in handicapped spaces. In the media analysis, 12 of the 75 drivers (16%) with medical 

conditions had leg, foot, or hip problems, including neuropathy and casts. DRSs concurred that 

peripheral neuropathy is likely to cause pedal applications errors; they noted that many of their 

clients were unaware that they had a loss of sensation in their feet. The DRSs also identified

cognitive impairment as a likely cause of pedal application errors. In the news media analysis, 28% 

of the reports that included a driver factor described medical conditions or medications, and in the 

NMVCCS analysis of pedal misapplication crashes 48% mentioned medications, the majority of 

which were potentially driver impairing.
88

The literature review revealed that negative transfer from other vehicles was a factor that 

may affect foot aiming accuracy (Schmidt, 1989; Lee et al., 2005; Perel, 1983; Pollard & Sussman, 

1989; Walter et al., 1988). Driver unfamiliarity with the vehicle may contribute to pedal application 

errors. However, driver unfamiliarity, gleaned through a review of the crash narratives, was 

associated with only 25 of the 2,411 pedal misapplication crashes in North Carolina (1%), 14 of the

subset of 266 crashes in news media reports where a driver factor was mentioned, and none of the 

NMVCCS pedal misapplication crashes.

Drivers who were out of position in the vehicle characterized 3% of the North Carolina pedal

misapplication crashes; crash narratives described drivers looking and reaching in the vehicle, 

resulting in inaccurate movements of the foot from gas to brake. Ten percent of the crash narratives 

in the NMVCCS analysis described drivers as “out of position,” as did 7% of the subset of news 

media reports where a driver factor was described. Other changes in head and body position away 

from front/center can also affect foot movement accuracy, as when a driver turns to check over the 

shoulder before backing out of a parking space. In the media analysis, 19 drivers had their heads or 

bodies directed away from the forward position when their pedal misapplication crashes occurred.

This behavior may help explain the high proportion of pedal misapplication crashes in parking lots, 

as discussed in the following pages. Complementing these findings, many of the DRS panelists 

commented about out-of-position drivers. They indicated that small women were often out of 

position because their “fit” in vehicles with a large seat pan was poor. 

Driver age and functional status may also explain variability in foot movement accuracy. In 

a driving simulator study, Cantin et al. (2004) found increased right foot movement variability in 

older drivers compared to younger drivers. Also, older drivers made several sub-movements of their 

right foot after they released the accelerator pedal in preparation for braking. This was rare among

younger drivers. The DRSs’ observations of foot “wandering” in their cognitively impaired older 

clients reinforced these findings. But caution is appropriate as neither the literature review nor the 

DRS observations tie pedal application errors directly to these (right foot) sub-movements.

Pedal misapplication crashes have also been associated with situations that startle drivers. 

According to Schmidt (1989), when drivers are startled or they panic, they often respond by

attempting to slam on the brake, especially if they perceive a sudden stimulus as being life 

threatening. Faster and more forceful foot movements result in less accuracy, which can lead to a 

pedal misapplication. In 19% of the North Carolina pedal misapplication crashes, drivers were 

described as startled or panicked. Drivers younger than 21 were over-represented in startle-related 

crashes in North Carolina while drivers older than 75 were underrepresented, with respect to their 

proportions in the sample. The media analysis described 20% of the drivers as startled or panicked.

Almost three-fifths (58%) of the NMVCCS pedal misapplication crashes were associated with a 

startle or panic response, based on the information presented in the crash narratives.

The analyses of crash location showed somewhat more disparate results. Analysis of North 

Carolina pedal misapplication crashes indicated that 57% of the crashes occurred in parking lots and 

driveways, while roadways accounted for 42%. In the media analysis, 77% of the pedal 

misapplication crashes occurred in residential parking lots, driveways, and parking garages, 

compared to 23% occurring on-road. The NMVCCS analysis did not include crashes in parking 

lots.
89

As noted earlier, the new media may deem an older driver involved in this type of crash 

more “newsworthy;” this could lead to the under-reporting of crashes involving younger and 

middle-aged drivers and the over-reporting of older driver crashes. In both analyses, older drivers 

were more likely than other drivers to be performing a parking maneuver prior to making a pedal 

application error. This could explain why the North Carolina crash analysis, which included larger 

percentages of middle-aged drivers, found more crashes occurring on-road than did the media 

analysis. The DRSs as a group also indicated most pedal application errors they observed in their 

clients occurred in parking lots. DRSs noted that their clients manifested one or more impairments 

that could undermine their driving abilities, so it is to be expected that they would have the greatest 

difficulty—and experience the greatest number of incidents—in parking lots, where there is less 

room to recover/correct a pedal misapplication given the proximity of cars and other objects. The 

DRSs hypothesized that many more pedal misapplications may occur on-road than showed up in the 

analyses, because drivers corrected the error, so it didn’t result in a crash. 

The previous findings can be better understood through a more detailed examination of the 

age distribution of drivers involved in pedal misapplication crashes, an area of considerable 

disparity across data sources. One picture emerges from a consideration of broad age groupings of 

these drivers revealed in each analysis (see Figure 11). In addition to the apparent underrepresentation of younger drivers and over-representation of older drivers in the media analysis 

compared to the North Carolina database analysis, the NMVCCS analysis shows a prevalence of 

pedal misapplication crashes by drivers age 21-35 that greatly exceeds both other sources.

Another picture emerges when crash involvement is plotted against 5-year age groupings, 

however (see Figure 12). Even allowing for a media bias toward reporting crashes involving older 

drivers, a familiar U-shaped curve is now revealed in both the media analysis and the analysis of the 

North Carolina crash database. And with regard to the North Carolina database analysis, it is 

important to note that while drivers age 16 to 20 and 76 and older each were involved in 17% of 

pedal misapplication crashes, the former group was involved in 15% of all crashes but the latter 

group in only 3%. On a proportional basis, this confirms older driver overinvolvement in pedal 

misapplication crashes.

Media Analysis 2000-2010 (n=683)

13%

10%

13%

25%

39%

<21

21-35

36-55

56-75

76+

North Carolina Crash Database 2004-2008 (n=2411)

20%

23%

20%

20%

17%

<21

21-35

36-55

56-75

76+

NMVCCS 2005 - 2007 (n=4,928 Weighted Data)

10%

39%

23%

3%

25% <21

21-35

36-55

56-75

76+

Figure 11. Comparison of Findings for Age, by Data Set
90

The U-shaped curve relating pedal misapplication crash involvement to driver age raises 

questions about possible underlying causes. The lack of experience among young/novice drivers 

certainly cannot be overlooked; this group is still learning simple vehicle control skills, and have 

not developed the muscle memory, nor the attentional, judgment, and decision making skills that are 

critical to smooth and safe vehicle operation. In the North Carolina database, 37% of drivers in 

pedal misapplication crashes had fewer than 4 years of driving experience. In the NMVCCS data, 

19% of the drivers were coded as inexperienced, the majority of whom were driving on a permit.

But the factor that best explains overinvolvement in these crashes at both ends of the driver 

age distribution is poor executive function. The areas of the brain that support executive function 

are the last to develop, not reaching full maturity until early adulthood (Zelazo, Craik, & Booth, 

2003). Corey-Bloom et al. (1996) found that the neuropsychological profiles of older (65 to 74

years old) and very old (85+) individuals could be distinguished almost exclusively by examining 

performance on executive tasks. Multiple studies have shown a relationship between poor 

performance on tests of executive function and increased crash risk. Specifically, Freund et al. 

(2008) found that drivers with deficits in executive functioning had increased pedal application 

error rates. The DRSs in the current study also reported pedal application errors among their clients 

who performed poorly in clinical tests of executive function (e.g., clock drawing, Trail-making), 

and this was not limited to older drivers. Another group they have observed making pedal 

misapplications includes young drivers with autism, attention-deficit disorder (ADD), and attention 

deficit hyperactivity disorder (ADHD).

Figure 12. Comparison of North Carolina Crash Database and Media Analysis 

Findings for Prevalence of Pedal Misapplication Crash Involvement by 5-Year 

Age Group.

0%

5%

10%

15%

20%

25%

30%

35%

40%

<16 16-20 21-25 26-30 31-35 36-40 41-45 46-50 51-55 56-60 61-65 66-70 71-75 76+

Driver Age Group

Percent of Drivers

NC Crash Database (n=2,399)

Media Analysis (n=683)
91

This is a less than satisfactory explanation for the other, overarching finding in these 

analyses, however, i.e., that women drivers involved in pedal misapplication crashes outnumber 

men by a margin of roughly 2 to 1, while male drivers account for approximately 60% of all 

crashes. Historically, exposure among male drivers has also been higher, although it is possible that 

this relationship could reverse for localized settings such as parking lots. It may be possible that 

women are disproportionately affected by a combination of contributory factors identified herein—

shorter stature resulting in poorer “fit” in their cars, and perhaps a greater susceptibility to startle 

responses—that, together, produce this discrepancy that was documented with such consistency 

across data sets. A difference in prevalence between sexes in impairing medical conditions or 

medication use also could merit investigation. All of these remain only unproven hypotheses at this 

point, begging further study.

The media analysis of pedal-related vehicle malfunction crashes screened to exclude 

behavioral causes (pedal application errors) and instead focus on crashes attributed to equipment 

malfunctions yielded several insights. The striking overrepresentation of females versus males 

disappeared in such crashes. Next, for a subset of events where media attention has been focused 

most intensively – stuck accelerator crashes – both the youngest and oldest driver age groups again 

appear to be at greatest risk. Alternatively, both groups may be the most newsworthy, so the media 

are more likely to report them. The data from the project indicate that the vehicle makes most 

overrepresented in equipment malfunction crashes from 2000-2010 in relation to their proportion of 

the U.S. fleet—all are domestic. 

It could be argued that, with the exception of the rare incident trumpeted in news reports 

(e.g., the Santa Monica crash) the consequences of pedal misapplication crashes are usually not 

severe. In the North Carolina database analysis, only 18% of those involved in a crash involving a 

pedal application error were injured—but this figure is for all road users, and jumps to 93% for 

pedestrians involved in such crashes. Still, less than 1% of the North Carolina crash victims 

received disabling injuries, and only 1 of 4,736 was killed. It is tempting to attribute the low fatality 

rate to the large proportion of crashes that occurred at low speeds and in parking lots; nearly half of 

the North Carolina pedal misapplication crashes (48%) occurred on roadways with speed limits of 

25 mph or less, and only 6% occurred on roadways with speed limits above 45 mph. These settings 

are not as benign as these summary statistics might suggest, however. Almost nine percent of the 

North Carolina pedal misapplication crashes resulting in serious (non-fatal) injuries occurred in 

parking lots, whereas only slightly over 1% of all non-fatal injurious crashes occurred in such 

locations. In the media analysis, which included larger percentages of parking lot crashes, 12% 

resulted in a fatality. In fact, the 108 fatal crashes included in the media analysis claimed the lives 

of 140 people, and 434 of the media-reported crashes (53%) resulted in more than a thousand 

injuries. An inescapable conclusion is that whenever pedal misapplication leads to the loss of 

control of a motor vehicle, and especially in settings where pedestrians are common, the potential 

for a tragic outcome is high.

Pedal application errors thus represent an aberrant driver behavior to which we attach safety 

concerns, at least in part, due to our aging population that remains overwhelmingly dependent on 

the private automobile for the activities of daily living. Research is needed to refine our 

understanding of the relative contributions of cognitive and functional impairments and of vehicle 

factors such as pedal characteristics and position within the vehicle on the incidence of pedal 

application errors. To the extent that variance in this behavior can be accounted for in terms of 
92

driver and vehicle factors, versus situational factors, countermeasure strategies will emerge that 

reinforce or expand upon the suggestions of the DRSs in this project. Some strategies merit 

immediate consideration: educational campaigns that target physicians, law enforcement, and 

DMVs about the potential for neuropathy to result in pedal application errors, and opportunities to 

identify, refer, and treat affected drivers. The public should be informed about the simple practice of 

shifting into neutral gear to counteract an unintended acceleration, regardless of the cause of the 

unintended acceleration (vehicle or driver). Finally, instituting a checklist for law enforcement to 

use for gathering information about drivers in pedal misapplication crashes can only lead to an 

improvement in traffic records that will in turn assist immeasurably in determining the causes of 

these incidents. 
93

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A-1

APPENDIX A: MEETING AGENDA AND MODERATOR’S GUIDE FOR DRIVER REHABILITATION 

SPECIALIST PANEL

Driver Rehabilitation Specialist Panel Meeting Agenda

Day 1: Thursday, August 19, 2010

12:00 - 1:00 p.m. Buffet lunch at hotel.

1:00 - 1:30 p.m. Introduction of Project and Panelists.

1:30 - 2:00 p.m. Summary of Findings from Literature Review and Analysis of Pedal Misapplication Crashes 

Reported in the Media 2000-2010.

2:00 - 3:30 p.m. Panel Discussion

Topic 1: Incidence of Pedal Misapplications

Topic 2: Descriptions of Incidents of Clients’ Pedal Misapplications

3:30-3:45 p.m. Break and Afternoon Coffee/Tea Service

3:45 – 5:15 p.m. Panel Discussion

Topic 3: Driving Tasks During Which these Errors Seem Most Likely to Occur

Topic 4: Characteristics of Drivers Most Likely to Make Pedal Application Errors

5:30 p.m. Adjourn meeting for the day. 

Day 2: Friday, August 20, 2010

8:00 -9:00 a.m. Buffet breakfast at hotel

9:00 – 10:45 Panel Discussion 

Wrap Up Topics Not Completed on Day 1

Topic 5: Behavioral Countermeasures That May Help Reduce the Incidence of 

Pedal Application Errors

10:45 – 11:00 a.m. Break

11:00 – noon Panel Discussion

Topic 6: What Kind of Research Might Help Explain the Causes of Pedal 

Application Errors or Support the Development of Countermeasures That 

May Prevent or Reduce their Occurrence?

12:00 – 1:00 p.m. Buffet Lunch at Hotel

1:00 – 3:00 p.m. Panel Discussion

Topic 7: Additional Insights Regarding Pedal Application Errors

3:00 Adjourn Meeting
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Moderator’s Guide For Driver Rehabilitation Specialist Panel

INTRODUCTION (30 MINUTES)

Hello. I am Loren Staplin and this is Kathy Lococo. We are working on a project for NHTSA to learn as much 

as we can about pedal misapplications—when drivers confuse the gas for the brake pedal. Sometimes this is called pedal 

application error or pedal confusion.

This is a problem identification study. The overall objective of this project is to find out how frequently crashes 

occur as the result of pedal misapplication; whether particular driver groups such as novices or older drivers are overrepresented in such crashes; if certain conditions place drivers at higher risk of pedal misapplication; and the extent of 

property damage, injuries, and fatalities caused by these errors. Unfortunately, this project started just before Toyota 

drivers began having crashes, stating that their accelerator pedals were sticking. For the present NHTSA study, we are 

focusing only on the driver behavioral problem of mistakenly pressing the gas pedal instead of the brake pedal. We are 

not focusing on vehicle malfunctions. 

You’ve all presumably looked at the Literature Review and analysis of crashes uncovered in the media over the 

past 10 years, which answer some of the questions about who has pedal error crashes and when they occur. Kathy will do 

a quick overview of the findings before we launch into discussions about your personal experiences.

We have asked you to participate in this meeting to learn more about pedal misapplications, as “on road 

veterans” in the field of driver assessment and rehabilitation, to get your first-hand accounts of your clients’ pedal 

application errors. This is because news media accounts and police reports present only part of the story; there is often 

more missing data in these reports than what is provided. Also, not all crashes are reported, so the data that we have are 

likely to be underestimations of the magnitude of the problem. It’s difficult to identify crashes caused by pedal 

misapplication because there is no code for this in crash databases. And when a pedal error crash is identified by 

searching through the police narrative section of a crash report, little if anything is reported about medical conditions, 

distractions, and task complexity in these crashes.

The kind of information we’re hoping we can learn from this panel includes:

• Descriptions of incidents where your clients pressed the gas instead of the brake.

• Driving tasks during which these errors seem most likely to occur: 

• Entering or leaving parking spaces?

• Backing up?

• Distracted?

• Turning?

• On-road or in parking lots?

• Crash avoidance maneuvers?

• Panic responses following loss of vehicle control?

• Characteristics of drivers most likely to make such errors

• Older drivers?

• Drivers with specific medical conditions or functional deficits?

• Footwear?

• Using adaptive equipment?

• Whether anything can be done to prevent or reduce pedal misapplication errors.

• Further study methods to learn more about pedal misapplications.
A-3

• Additional insights regarding pedal application errors.

I’d like to start by asking each of you introduce yourselves, and briefly describe your work experience.

OVERVIEW OF FINDINGS FROM THE LITERATURE REVIEW AND ANALYSIS OF CRASHES 

REPORTED IN THE MEDIA (30 MINUTES)

Kathy will get us up to speed with what we’ve learned so far in this project, and then, we’ll turn things over to 

you, the experts!

PANEL DISCUSSIONS (3 HOURS ON DAY 1 AND 5 HOURS ON DAY 2)

Topic 1: Incidence of Pedal Misapplications

• How many of you have been in a vehicle with a client who mistook the gas for the brake (or viewed a driver in 

a simulator who made a pedal application error)?

• For those who have, how many clients or incidents have you observed?

• Did any of these incidents lead to a crash?

Topic 2: Descriptions of Incidents of Clients’ Pedal Misapplications

For those who have witnessed incidences of pedal misapplications, try to describe each in as much detail as 

possible, including driver, vehicle, and environmental characteristics.

Topic 3: Driving Tasks During Which these Errors Seem Most Likely to Occur

We’ve heard the individual stories, which included lots of detail, but now let’s try to categorize this 

information.

• Where are pedal misapplications most likely to occur? 

(e.g., parking lots, on the road, at intersections, in the driver’s driveway).

• What was the driver trying to do just prior to the error? 

(e.g., enter or leave a parking space in a parking lot, driveway, or on road; turning at an intersection; slowing 

down for vehicles ahead that were stopping at an intersection; slowing down for pedestrians crossing the road; 

recover from a loss of vehicle control; recover from hitting a curb or parking block in a parking lot; recover 

from a crash; avoid a crash)

• What else was happening inside the vehicle and outside the vehicle just prior to the errors? Try to remember 

the traffic situation, and pedestrians.

• Was the driver distracted by anything, either inside or outside of the vehicle?

• Did the driver realize he/she had hit the wrong pedal? Did they correct it or did you have to intervene? Did 

the driver panic and hit the gas again or continue to press on the gas?

• Were the drivers driving their own cars or a vehicle from the rehab or driver training program?

• Other insights into driving tasks associated with pedal misapplications
A-4

Topic 4: Characteristics of Drivers Most Likely to Make Pedal Application Errors

Again, we’re trying to categorize, if possible, who is mistaking the gas pedal for the brake. Is it generally:

• Older drivers?

• Cognitively impaired drivers?

• Novice drivers?

• Drivers unfamiliar with the vehicle?

• Drivers with medical conditions or taking medications (diabetic neuropathy, broken foot)?

• Young drivers with ADD?

• Drivers learning to use adaptive equipment?

• Any driver/any age who is distracted?

• Drivers startled or trying to make a panic stop?

• Drivers wearing certain kinds of shoes (e.g., diabetes shoes)?

• Two-footed drivers?

• Drivers using cruise control?

• Other insights into driving tasks associated with pedal misapplications

Topic 5: Are There Any Types of Behavioral Countermeasures That May Help Reduce the Incidence of Pedal 

Application Errors?

Based on the characteristics surrounding pedal misapplication crashes, let’s brainstorm about what 

countermeasures might help reduce or prevent pedal misapplication incidences, or help a driver realize that they’ve 

made a pedal application error so they can correct it before they get into a crash.

[Let panelists come up with and discuss their own ideas; if necessary, use the following examples as probes to 

generate discussion.]

• Education?

• In-Vehicle Warnings? (auditory, visual)

• Sensor on Accelerator and Brake Override?

Topic 6: What Kind of Research Might Help Explain the Causes of Pedal Application Errors or Support the 

Development of Countermeasures that May Prevent or Reduce their Occurrence?

• Laboratory/simulator studies?

• Instrumented vehicle studies?

• On-road, closed course studies?

• Who should the subjects be?

• What driving situations should be included?

• What environmental situations should be included?

Topic 7: Additional Insights Regarding Pedal Application Errors.

If there are areas that we haven’t discussed over the past two days, please share additional thoughts with us.
B-1

APPENDIX B:

BODY OF LETTER SENT BY NORTH CAROLINA GOVERNOR’S HIGHWAY SAFETY 

PROGRAM TO SELECTED DRIVERS WHO HAD PEDAL MISAPPLICATION

CRASHES IN 2008.

Dear ________________,

The North Carolina Governor’s Highway Safety Program is helping the National Highway Traffic Safety 

Administration (NHTSA) on a project to learn more about motor vehicle crashes where a person’s car seemed to 

accelerate when they meant it to stop. We have identified over 500 such crashes in North Carolina alone, during the 

year 2008. 

We are asking you to volunteer 15 minutes of your time to participate in a telephone conversation with a researcher 

about a crash you had in 2008. You are under no obligation to participate in this interview, but we hope that you decide 

to help. There will be no effect on your license, whether you choose to participate or not.

The company conducting the research for NHTSA is called TransAnalytics. The researcher you talk to will not ask you 

for your name or your driver license number, so the information you provide will remain anonymous. The information 

discussed during the phone call will be summarized in a report to NHTSA along with information provided by about 

100 other North Carolinians. No information from the discussions will be provided to the Department of Motor 

Vehicles.

Thank you for considering this request to help make our highways safer. The telephone conversations will happen 

during the month of November. If you have 15 minutes to contribute in November, please call TransAnalytics (toll 

free) at 1-866-650-5380, extension 104. You will talk with Kathy Lococo. She is available to take your call Monday 

through Friday, from 10 a.m. to 4 p.m. 
C-1

APPENDIX C:

DISCUSSION GUIDE FOR ONE-ON-ONE UNSTRUCTURED CONVERSATIONS IN CASE STUDIES 

ABOUT PEDAL APPLICATION ERRORS

(Revise the wording and order of questions across subjects)

“Thank you for calling. This research is dedicated to learning more about car crashes where the driver means to stop, 

but the car speeds up instead. Is this what happened to you in your accident a couple of years ago?” 

Yes: ______ No: __________

Crash Circumstances 

“Now please tell me what you remember about that crash.” 

(Write what they say, and probe, if possible for the following):

• Location (intersection, parking lot)

• Maneuver (parking, slowing, stopping, changing lanes, crash or obstacle avoidance)

• Use of cruise control

• Pedal Control (one foot, both feet)

• Kind of shoes

• Distractions (passengers, cell phones, eating, drinking smoking, dropped something, reaching, adjusting 

radio, something outside of vehicle)

• Feeling rushed

• Startled by anything

• Hit wrong pedal, foot slipped, or equipment malfunction
C-2

Medical Conditions and Medications

“Please tell me about any medical conditions you have and the kinds of prescription medications and over-the-counter 

remedies you take.”

(List what they say, and probe, if possible for)

• Height

• Handicap placard for car

• Diabetes (and if yes, special shoes for this, and do you wear them when you drive?) 

• Foot or leg pain

• Loss of feeling in your feet or legs 

• Difficulty moving foot back and forth between gas and brake pedals

• Tingling in your feet or feeling different temperatures in the feet 

• Use of medication called neurontin 

• Need to look at feet when walking to keep from tripping 

• Surgery on hips, knees, or ankles in the past 5 years 

• Drive with a brace, cast, or prosthesis on legs 

• Cerebral Palsy

• Multiple Sclerosis

• Stroke

• Parkinson’s Disease

• Alzheimer’s

• Attention Deficit Disorder

“Are any of these medical conditions or medications new? I mean, since the time of your accident?”
C-3

Driving Experience

“Tell me about your driving experience: how long you’ve had a license and how often you drive.”

(Write what they say, and probe for miles per year, or trips per day, or number of driving days per week)

What kind of car you were driving when you had the crash?

(Write what they say, and try to get):

• Make

• Model

• Year

• Length of time owned prior to crash

• Automatic or manual transmission

• Adaptive equipment

• Easy to adjust seat position

• Easy to reach pedals

• Comfortable to drive
C-4

Closing Comments

“Is there anything else you can tell me about why this crash happened?”

If yes, write what they say:

Thank you again for your time. I’ve enjoyed hearing your story, and wish you well. 
D-1

APPENDIX D:

SUPPLEMENTAL DATA FROM THE NORTH CAROLINA CRASH ANALYSIS, MEDIA ANALYSIS, AND 

NMVCCS ANALYSIS

Figure D-2. Frequency Distribution of Pedal Misapplication Crashes by Driver Age

(North Carolina State Crash Database 2004 – 2008, n=2,399)

0

10

20

30

40

50

60

70

80

90

100

8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 74 76 78 80 82 84 86 88 90 92 94 96

Driver Age

Number of Drivers

Figure D-1. Frequency Distribution of Pedal Misapplication Crashes by Driver Age

(News Media Analysis, 2000-2010, n=683)

0

5

10

15

20

25

30

1013151719212325272931333537394143454749515355575961636567697173757779818385878991939597

Driver Age

Number of Crashes
D-2

Table D-1. Crash Time of Day Associated With Pedal Misapplication Crashes, for North Carolina Crash 

Database, Media, and NMVCCS Samples

Hour of Crash Percent of Crashes

NC Crash Database Media NMVCCS

12 a.m. - 5:59 a.m. 3% 3% 0%

6 a.m. - 8:59 a.m. 9% 10% 14%

9 a.m. - 11:59 a.m. 21% 32% 4%

12 p.m. - 2:59 p.m. 26% 26% 42%

3 p.m. - 5:59 p.m. 22% 19% 10%

6 p.m. - 8:59 p.m. 13% 7% 24%

9 p.m. - 11:59 p.m. 6% 3% 6%
D-3

Table D-2. Pre-Crash Maneuver by Driver Age Group (North Carolina Crash Database Sample)

Pre-Crash Maneuver

Driver Age Group

All <21 21-35 36-55 56-75 76+

N % N % N % N % N % N %

Stopped in travel lane 6 1% 8 1% 5 1% 7 1% 1 0% 27 1%

Parked out of travel lanes 1 0% 4 1% 7 1% 4 1% 2 0% 18 1%

Parked in travel lanes 1 0% 0 0% 1 0% 1 0% 0 0% 3 0%

Going straight ahead 184 39% 235 43% 212 44% 178 37% 118 28% 927 39%

Changing lanes or merging 0 0% 2 0% 4 1% 4 1% 2 0% 12 1%

Passing 1 0% 1 0% 0 0% 1 0% 0 0% 3 0%

Making right turn 34 7% 31 6% 20 4% 19 4% 15 4% 119 5%

Making left turn 38 8% 25 5% 20 4% 14 3% 14 3% 111 5%

Making u turn 1 0% 9 2% 2 0% 2 0% 1 0% 15 1%

Backing 53 11% 33 6% 53 11% 47 10% 68 16% 254 11%

Slowing or stopping 18 4% 39 7% 20 4% 26 5% 12 3% 115 5%

Starting in roadway 10 2% 14 3% 7 1% 13 3% 4 1% 48 2%

Parking 90 19% 115 21% 101 21% 146 30% 146 35% 598 25%

Leaving parked position 15 3% 12 2% 14 3% 13 3% 19 5% 73 3%

Avoiding object in road 5 1% 7 1% 1 0% 1 0% 1 0% 15 1%

Other 15 3% 10 2% 10 2% 8 2% 16 4% 59 2%

All 472 100% 545 100% 477 100% 484 100% 419 100% 2,397 100%
D-4

Table D-3. Frequency and Percentage* of Pedal Misapplication Pre-Crash Maneuvers by Age Group

(Media Sample)

Pre-Crash Maneuver Total Driver Age Group

20 or Less 21-35 36-55 56-75 76+

Entering parking space 259 34

(47%)

30

(48%)

20

(31%)

74

(54%)

101

(51%)

Leaving parking space 64 8

(11%)

6

(10%)

8

(12%)

8

(6%)

34

(17%)

Turning 50 6

(8%)

4

(6%)

3

(5%)

16

(12%)

21

(11%)

Driving in lane 17 2

(3%)

2

(3%)

4

(6%)

2

(1%)

7

(4%)

Changing lanes 3 -- -- -- 1

(1%)

2

(1%)

Stopped 1 -- -- -- 1

(1%) --

Slowing/stopping for traffic 

control device, vehicles, or 

pedestrians

30 3

(4%)

3

(5%)

4

(6%)

6

(4%)

14

(7%)

Startle braking following 

collision, loss of control of 

vehicle, or collision 

avoidance maneuver

111 20

(27%)

18

(29%)

26

(40%)

28

(21%)

19

(10%)

Total 535 73 63 65 136 198

* Percentages of drivers in each age category (column percents)
D-5

Table D-4. Frequency With Which Driver Actions Were Coded as a Contributing Factor 

(either 1st, 2nd, or 3rd), and Percentage of Crashes in Which Driver Actions Contributed to Pedal 

Misapplication Crashes (North Carolina Crash Database Sample)

Driver Contributing Circumstance

Frequency Driver Action Was 

Coded as a Contributing 

Circumstance

(Either 1st, 2nd, or 3rd)

Percentage of 

Crashes*

(n=2330)

Inattention 1016 43.6%

Failure to reduce speed 678 29.1%

Other 407 17.5%

Operated vehicle in erratic, reckless, careless, negligent, 

or aggressive manner

235 10.1%

Improper parking 209 9.0%

Improper backing 177 7.6%

Overcorrected/oversteered 109 4.7%

Driver distracted 102 4.4%

Failed to yield right of way 79 3.4%

Exceeded safe speed for conditions 65 2.8%

Improper turn 51 2.2%

Followed too closely 40 1.7%

Crossed centerline/going wrong way 27 1.2%

Swerved or avoided due to wind, slippery surface, 

vehicle, object, or non-motorist 26 1.1%

Disregarded stop sign 25 1.1%

Alcohol use 24 1.0%

Disregarded traffic signals 22 0.9%

Exceeded authorized speed limit 22 0.9%

Operated defective equipment 16 0.7%

Visibility obstructed 8 0.3%

Improper lane change 6 0.3%

Drug use 3 0.1%

Disregarded road markings 2 0.1%

Disregarded yield sign 2 0.1%

Other improper passing 2 0.1%

Use of improper lane 2 0.1%

Improper or no signal 1 0.0%

Passed stopped school bus 1 0.0%

Right turn on red 1 0.0%

* Percentages add up to more than 100, because up to three driver contributing factors could be coded per crash
D-6

Table D-5. Frequency (and Percentage) of Crashes Associated With Specific Driver Physical Conditions, by Driver Age Group (North Carolina Crash 

Analysis)

Physical Condition

Driver Age Group All <21 21-35 36-55 56-75 76+

Frequency Percent Frequency Percent Frequency Percent Frequency Percent Frequency Percent Frequency Percent

Apparently normal 454 96% 521 96% 435 91% 446 92% 379 90% 2235 93%

Illness 0 0% 1 0% 3 1% 1 0% 2 0% 7 0%

Fatigue 2 0% 3 1% 7 1% 0 0% 1 0% 13 1%

Fell asleep, fainted, loss of 

consciousness 1 0% 0 0% 2 0% 1 0% 1 0% 5 0%

Impairment due to medications, 

drugs, alcohol 4 1% 8 1% 8 2% 3 1% 1 0% 25 1%

Medical condition 1 0% 1 0% 8 2% 16 3% 2 0% 28 1%

Other physical impairment 0 0% 2 0% 3 1% 5 1% 13 3% 23 1%

Restriction not complied with 1 0% 0 0% 1 0% 0 0% 1 0% 3 0%

Other 2 0% 3 1% 2 0% 4 1% 6 1% 17 1%

Unknown 7 1% 6 1% 8 2% 8 2% 13 3% 43 2%

All 472 100% 545 100% 477 100% 484 100% 419 100% 2399 100%
D-7

Table D-6. Year of Vehicles Driven by Pedal Misapplication Crash-Involved Drivers 

in North Carolina (2004-2008)

Vehicle Year Number Percent

1966 2 <1%

1967 1 <1%

1971 2 <1%

1972 1 <1%

1975 1 <1%

1978 1 <1%

1979 1 <1%

1980 2 <1%

1981 4 <1%

1982 2 <1%

1983 3 <1%

1984 6 <1%

1985 10 <1%

1986 11 <1%

1987 18 1%

1988 30 1%

1989 42 2%

1990 62 3%

1991 61 3%

1992 75 3%

1993 94 4%

1994 103 4%

1995 128 5%

1996 139 6%

1997 163 7%

1998 144 6%

1999 169 7%

2000 168 7%

2001 158 7%

2002 167 7%

2003 181 8%

2004 140 6%

2005 129 5%

2006 82 3%

2007 61 3%

2008 26 1%

2009 2 0%

Total 2,389 100%
D-8

Table D-7. Driver Injury Status by Age Group (North Carolina Crash Analysis)

Injury Status

Driver Age Group All

<21 21-35 36-55 56-75 76+

Number Percent Number Percent Number Percent Number Percent Number Percent Number Percent

Fatal injury (K) 0 0% 0 0% 0 0% 0 0% 1 0% 1 0%

Disabling injury (A) 0 0% 1 0% 2 0% 0 0% 2 0% 5 0%

Evident injury (B) 19 4% 14 3% 17 4% 17 4% 30 7% 97 4%

Possible injury (C) 41 9% 50 9% 51 11% 63 13% 56 14% 261 11%

No injury (O) 407 87% 477 88% 397 85% 398 83% 324 78% 2,003 85%

Total 467 100% 542 100% 467 100% 478 100% 413 100% 2,367 100%
E-1

APPENDIX E:

MEDICAL CONDITIONS OR SYMPTOMS LISTED BY THE DRSS THAT CAN CAUSE (OR DESCRIBE)

PROPRIOCEPTION OR SENSORY DEFICITS IN THE LEGS

• Peripheral neuropathy*

• Diabetes*

• Multiple sclerosis*

• Proprioceptive/kinesthetic deficits*

• Spinal cord injury*

• Spinal stenosis*

• Nerve disorders (pinched nerves/sciatica)*

• Hip/knee replacement

• Stroke

• Pain in the leg/paresthesis/reflex sympathetic dystrophy

• Vascular diseases

• Pins and needles sensation; numb

• Edema

• Lymphoma

• Cancer/chemotherapy

• Cerebral palsy

• Spina bifida

• Poor healing from cuts/sores

• Parkinson’s

• Fatigue

• Foot drop

• Amputation/prosthesis/ankle/foot orthosis

• Muscular dystrophy

• Head injury 

• Lower extremity injury (something that severs a nerve, e.g., a gunshot wound or other 

trauma to the leg that impacts sensation)

• Back pain

• Polio

• Gout

• Gullian-Barré

• Amyotrophic lateral sclerosis (ALS, “Lou Gehrig's disease”)

• Arthritis

• Ataxia

• Extensor tone

• Too short/poor positioning in the vehicle seat

• Charcot-Marie-tooth disease (CMT)

• Lyme disease

• Restless legs syndrome

• Leg cramps

• Medications/contraindications

• Radioculopathy

* Received the most ratings by DRSs as being of greatest concern in contributing to loss of sensation in 

lower extremities.
F-1

APPENDIX F:

COGNITIVE IMPAIRMENTS THAT MAY EXPLAIN WHY DRIVERS DO NOT CORRECT A PEDAL 

APPLICATION ERROR, ONCE ONE IS MADE

• Alzheimer’s and memory disorders*

• Parkinson’s disease (and other movement disorders)*

• Anxiety*

• Asperger’s*

• Cerebral palsy*

• Multiple sclerosis*

• Traumatic brain injury (TBI)*

• Stroke (CVA; right hemisphere/left hemiplegia)*

• Anoxia*

• Transient ischemic attacks (TIA)

• Autism

• Learning disability/ADD (attention-deficit disorder)

• Non-verbal learning disabilities

• Brain tumors and aneurysms

• Spina bifida

• (Over)-medication

• Failure to take medications on schedule

• Huntington’s

• Executive function deficit (which is a symptom of many conditions, e.g., anoxia, TBI, dementia)

• Low IQ

• Post-polio

• Muscular dystrophy

• Sleep apnea

• Chronic obstructive pulmonary disease (COPD)

• Post cardiac surgery, cardiac disorders

• Seizure disorder

* Received the most ratings by DRSs as being of greatest concern in contributing to failure to correct a pedal 

application error. 
G-1

APPENDIX G: Supporting Tables for Media Analysis of Equipment Malfunction Crashes

(asterisks denote missing data for make, model, and/or year)

Table G-1. Make, Model and Year for Other-Corroborated Equipment Malfunction Crashes.

Make Model Year

(other Corroborated Equipment Malfunction) Vehicle Type

* * 1993 Pickup Truck

* * 1997 Pickup Truck

Buick Park Avenue 1991 Passenger Car

Buick * * Passenger Car

Buick * 1964 Passenger Car

Buick Electra 1980 Passenger Car

Buick LaSabre 2005 Passenger Car

Buick Regal 1986 Passenger Car

Cadillac * * Passenger Car

Cadillac * 1987 Passenger Car

Chevrolet * * Passenger Car

Chevrolet * 1963 Pickup Truck

Chevrolet * 1982 Pickup Truck

Chevrolet * 1984 Van

Chevrolet * 1993 Passenger Car

Chevrolet Malibu * Passenger Car

Chevrolet S-150 1995 Pickup Truck

Chevrolet * 1988 Passenger Car

Chevrolet * 1995 Pickup Truck

Chevrolet * 1997 Passenger Car

Chrysler Concorde 1997 Passenger Car

Dodge 3/4 Ton 1990 Pickup Truck

Dodge Caravan 1989 Van

Dodge Ram 1996 Pickup Truck

Fiat * 1967 Passenger Car

Ford * * Pickup Truck

Ford * 1977 Dump Truck

Ford * 1990 Passenger Car

Ford * 1993 Passenger Car

Ford * 2006 Pickup Truck

Ford Crown Victoria * Passenger Car

Ford Crown Victoria 1987 Passenger Car

Ford Crown Victoria 1999 Passenger Car

Ford Crown Victoria 2006 Passenger Car

Ford Econoline 1992 Van

Ford Explorer * SUV

Ford Explorer 1994 SUV

Ford Escort 1998 Passenger Car

Ford Excursion * SUV
G-2

Make Model Year

(other Corroborated Equipment Malfunction) Vehicle Type

Ford F150 * Pickup Truck

Ford Focus ZX4 2005 Passenger Car

Ford LTD 1981 Passenger Car

Ford LTD 1983 Passenger Car

Ford Mustang * Passenger Car

Ford Mustang 1997 Passenger Car

Ford Ranger * Pickup Truck

Ford Taurus 1992 Passenger Car

Ford Taurus 1992 Passenger Car

Ford Taurus 1992 Passenger Car

Ford Windstar * Van

GMC Envoy * SUV

GMC * 1993 Dump Truck

GMC * 2002 SUV

Honda Accord * Passenger Car

Honda Passport * Passenger Car

Honda Accord 1994 Passenger Car

International 4700 1999 Dump Truck

Jaguar * * Passenger Car

Jeep Grand Cherokee 2004 SUV

Kia Sephia * Passenger Car

Lexus ES350 2007 Passenger Car

Lexus ES350 2009 Passenger Car

Lincoln Navigator * SUV

Lincoln Town Car 1991 Passenger Car

Lincoln Town Car 2001 Passenger Car

Mazda * 1992 Passenger Car

Mercury * 1997 Passenger Car

Mercury Grand Marquis * Passenger Car

Mitsubishi Eclipse 1994 Passenger Car

Nissan Maxima 1995 Passenger Car

Nissan Pulsar 1989 Passenger Car

Oldsmobile * 1986 Passenger Car

Oldsmobile Cutlass Supreme 1978 Passenger Car

Plymouth Voyager 1993 Van

Pontiac Bonneville * Passenger Car

Pontiac Firebird 1994 Passenger Car

Pontiac Grand Am 1986 Passenger Car

Pontiac Grand Am 1991 Passenger Car

Pontiac Grand Prix 2004 Passenger Car

Toyota Camry 1997 Passenger Car

Toyota Corolla 1994 Passenger Car

Toyota Camry 2007 Passenger Car
G-3

Make Model Year

(other Corroborated Equipment Malfunction) Vehicle Type

Toyota Tacoma * Pickup Truck

Volkswagen Passat 2002 Passenger Car

Volvo * * Passenger Car

Volvo * 1997 Tractor Trailer

Volvo * 2001 Tractor Trailer

Table G-2. Make, Model and Year for Self-Reported-Only Equipment Malfunction Crashes.

Make Model Year

(Self-Reported Equipment Malfunction) Vehicle Type

Acura * * Passenger Car

Acura MDX * SUV

BMW * * Passenger Car

BMW * * SUV

BMW * * Passenger Car

BMW * 1989 Passenger Car

BMW X3 2007 SUV

Bouse House * * Other Truck

Buick * * Passenger Car

Buick * 1991 Passenger Car

Buick * 1991 Passenger Car

Buick * 1996 Passenger Car

Buick Riviera 1989 Passenger Car

Cadillac * * Passenger Car

Cadillac * * Passenger Car

Cadillac * * Passenger Car

Cadillac * 1988 Passenger Car

Chevrolet * 1979 Pickup Truck

Chevrolet * * Passenger Car

Chevrolet * 1985 Pickup Truck

Chevrolet * 1996 Pickup Truck

Chevrolet * 2003 Pickup Truck

Chevrolet Blazer 2000 SUV

Chevrolet Caprice 1995 Passenger Car

Chevrolet Cobalt * Passenger Car

Chevrolet Equinox * SUV

Chevrolet S-10 * Pickup Truck

Chevrolet Suburban * SUV

Chevrolet Tahoe * SUV

Chevrolet Z28 1980 Passenger Car

Chevrolet Blazer * SUV

Chevrolet Blazer * SUV

Chevrolet Celebrity 1988 Passenger Car
G-4

Chevrolet Impala * Passenger Car

Chevrolet Lumina 1992 Passenger Car

Chevrolet Lumina 1994 Passenger Car

Chevrolet S10 * Pickup Truck

Chevrolet Silverado * Pickup Truck

Chevrolet Silverado 1999 Pickup Truck

Chrysler Sebring * Passenger Car

Dodge * 1973 Pickup Truck

Dodge * 1993 Van

Dodge * 2000 Van

Dodge * 2001 Passenger Car

Dodge Durango 2003 SUV

Dodge Intrepid 1995 Passenger Car

Dodge Intrepid 1998 Passenger Car

Dodge Ram * Pickup Truck

Dodge Ram 1500 * Pickup Truck

Dodge Ram 1995 Pickup Truck

Dodge Ram Charger * Pickup Truck

Dodge Stratus 1999 Passenger Car

Ford Aerostar * Van

Ford Bronco * SUV

Ford Escape 2005 SUV

Ford Escort * Passenger Car

Ford Escort 2002 Passenger Car

Ford Explorer * SUV

Ford Explorer * SUV

Ford Explorer 1998 SUV

Ford F-150 * Pickup Truck

Ford F-250 1995 Pickup Truck

Ford F350 * Pickup Truck

Ford Focus 2000 Passenger Car

Ford Mustang 1966 Passenger Car

Ford Taurus 1995 Passenger Car

Ford * * Passenger Car

Ford * 1991 Passenger Car

Ford * 1994 Van

Ford Aerostar * Van

Ford Bronco * Pickup Truck

Ford Contour * Passenger Car

Ford Crown Victoria 1989 Passenger Car

Ford Crown Victoria 1989 Passenger Car

Ford Crown Victoria 1999 Passenger Car

Ford Econoline * Van

Ford Escape 2006 SUV

Ford Expedition 1997 SUV

Ford F-150 * Pickup Truck
G-5

Ford Mustang * Passenger Car

Ford Mustang 1965 Passenger Car

Ford Taurus * Passenger Car

Ford Windstar * Van

Ford Windstar * Van

Ford Windstar 1998 Van

Freightliner * * School Bus

GMC * * Pickup Truck

GMC * 1999 Passenger Car

GMC Sierra 2000 Pickup Truck

GMC Yukon 2006 SUV

Honda * 1995 Passenger Car

Honda Accord * Passenger Car

Honda Accord * Passenger Car

Honda Accord 1988 Passenger Car

Honda Passport 1997 Pickup Truck

Hyundai * 2002 Passenger Car

Jeep Cherokee * SUV

Jeep * * SUV

Jeep * 1988 SUV

Jeep Cherokee * SUV

Jeep Cherokee * SUV

Jeep Cherokee Laredo 1996 SUV

Jeep CJ7 1984 SUV

Jeep Grand Cherokee * SUV

Jeep Grand Cherokee 2003 SUV

Jeep Liberty 2002 SUV

Kia * 2004 Van

Kia Sephia 1996 Passenger Car

Lincoln Navigator * SUV

Lincoln Town Car 2001 Passenger Car

Lincoln * 1988 Passenger Car

Lincoln Town Car * Passenger Car

Mazda * 1999 Pickup Truck

Mazda Protégé * Passenger Car

Mazda Tribute * Passenger Car

Mercedes-Benz * * Passenger Car

Mercedes-Benz * * SUV

Mercedes-Benz * * Passenger Car

Mercury Sable 2004 Passenger Car

Mercury * * Passenger Car

Mercury * 1993 Van

Mercury Cougar 1984 Passenger Car

Mercury Grand Marquis 2002 Passenger Car

Mercury Marquis 1992 Passenger Car

Mercury Tracer 1991 Passenger Car
G-6

Mitsubishi Montero 1999 SUV

Mitsubishi Montero 2002 SUV

Nissan * * Passenger Car

Nissan * 1986 Passenger Car

Oldsmobile * 1984 Passenger Car

Oldsmobile * 1985 Passenger Car

Oldsmobile * 1999 Passenger Car

Oldsmobile 88 1998 Passenger Car

Oldsmobile Cutlass 1983 Passenger Car

Oldsmobile Cutlass 1993 Passenger Car

Oldsmobile Cutlass 1995 Passenger Car

Oldsmobile Cutlass Ciera 1992 Passenger Car

Oldsmobile Regency 1987 Passenger Car

Plymouth * 1971 Passenger Car

Pontiac Bonneville 1994 Passenger Car

Pontiac Grand Am * Passenger Car

Pontiac Grand Am 1999 Passenger Car

Pontiac Grand Prix * Passenger Car

Pontiac Grand Prix 1977 Passenger Car

Pontiac Sunbird 1993 Passenger Car

Saab * 2002 Passenger Car

Toyota * 1983 Pickup Truck

Toyota Camry * Passenger Car

Toyota Camry 2000 Passenger Car

Toyota Tacoma * Pickup Truck

Toyota * * Pickup Truck

Toyota * 2006 Passenger Car

Toyota Camry * Passenger Car

Toyota Corolla * Passenger Car

Toyota Corolla 1996 Passenger Car

Toyota Prius 2003 Passenger Car

Volvo * 1983 Passenger Car

Volvo 740 GL * Passenger Car

Volvo 740 Turbo 1987 Passenger Car
DOT HS 811 597 

March 2012

8461-032912-v2