NHTSA: Research & Evaluation Logo

Back to Injury Prevention Page
Back to nhtsa Web Site

skip nav
What's New

Alcohol-Impaired Driving
Drug-Impaired Driving
Occupant Protection
Speed and Aggressive Driving
Pedestrian and Bicyclist Safety
Motorcyclist Safety
Older Driver Safety
Improving Emergency Medical Services
Drowsy Driving
New Driver Safety
Other Traffic Safety Research


[ AC ]

A Study of Outstanding DWI Warrants (posted 8/29/01)
One loophole in the adjudication and sanction process for DWI cases is the number of individuals arrested for DWI who fail to appear (FTA) in court or fail to comply (FTC) with court-ordered sanctions. This study examined outstanding warrant data from 19 sites for people who either did not appear for their court date or did not comply with their sanctions. It was learned that for many localities, FTAs and FTCs are a substantial problem, with the number of outstanding warrants running into the thousands or the tens of thousands.

A Review of the Literature on the Effects of Low Doses of Alcohol on Driving-Related Skills ( posted 01-00)
A review of the scientific literature of the effects of alcohol on driving related skills examined the lowest BAC at which impairment was reliably present, and the thresholds of impairment for several behavioral areas. Authors concluded that all drivers can be expected to experience impairment in some driving-related skills by 0.08 g/dl or less.

Alcohol and Highway Safety 2001 (posted November 11-01)

Addressing Alcohol-Impaired Driving: Training Physicians to Detect and Counsel Their Patients Who Drink Heavily (posted 07-00)
Alcohol is the most common chronic disease in trauma patients, and one of the most common in patients treated in primary care. The goal of this project was to address alcohol abuse at the individual level and at the community level.
Age of Drinking Onset, Driving After Drinking, and Involvement in Alcohol-Related Motor Vehicle Crashes (posted 01-01)
This study assessed whether people who begin drinking at younger ages are more likely to report drunk driving and alcohol-related crash involvement during their life, even after controlling for alcohol dependence and other personal characteristics associated with the age respondents started drinking.

Age of Drinking Onset and Unintentional Injury Involvement After Drinking  (posted 01-01)
This study assessed whether persons who begin drinking at younger ages are more likely to report unintentional injuries under the influence of alcohol.

Alcohol Highway Safety: Problem Update
For those in the traffic safety community, having information on the latest research in alcohol-impaired driving is a critical necessity. Since 1968, the Department of Transportation has conducted periodic reviews on the "state of knowledge" about alcohol and traffic safety. This newest state of knowledge report focuses on alcohol-crash targets.

An Impact Evaluation of Underage Drinking Prevention Projects (posted 12/04/03)
This report presents the results of an impact evaluation of four community-based underage drinking prevention projects stimulated by technical assistance coordinated by the National Association of Governor’s Highway Safety Representatives (now called the Governors Highway Safety Association) with funding provided by the National Highway Traffic Safety Administration. The four programs which were studied were located in: Chesterfield County, Virginia; Omaha, Nebraska; Salt Lake County, Utah; and Travis County, Texas. The impact evaluation focused on the effect of the programs on proxy measures of alcohol-related crashes among youth.

[ D-F ]

Determine Reasons for Repeat Drinking and Driving (reasons.pdf, 174K, posted 06-96) This report summarizes the results of a study to learn why some individuals continue to drive after drinking, even after being convicted of DWI one or more times. Interviews were conducted with repeat offenders in three sites. Promising countermeasures and sanctions are discussed.

Develop and Test Messages to Deter Drinking and Driving
This project targeted 18 to 25 year-olds. This group was chosen because they remain at high risk for DWI, and because they are still young enough that making changes in their drinking and driving patterns is a strong possibility. These messages are based around being there for a friend (driving a drunk friend home), and letting a friend be there for you (driving you home if you're impaired).

Development, Implementation and Evaluation of a Countermeasure Program for Alcohol-Involved Pedestrian Crashes. Final Report.(posted 06-00)
The objectives of this study were to analyze the pedestrian alcohol problem in a community and to develop and apply procedures to counter the problem.

Driver Characteristics and Impairment at Various BACs (posted 09-00) Also available in .pdf
This laboratory study examined the effects of alcohol on driving skills at BACs of 0.00% to 0.10% in a sample of 168 subjects assigned to age, gender, and drinking practices groups. The study was designed to determine the BACs at which impairment of specific experimental tasks occur and the interaction of age, gender and drinking practices with BAC on the magnitude of impairment.

Effectiveness of the Ohio Vehicle Action and Administrative License Suspension Laws
In September, 1993, Ohio implemented two laws related to alcohol impairment. One provided for immediate license suspension on the day of arrest for all offenders caught driving under the influence (DUI). The other law permitted vehicles to be immobilized for up to 90 days upon conviction of a second DUI offense and 180 days upon conviction of a third DUI offense. An evaluation of administrative license suspension was conducted statewide whereas evaluation of vehicle impoundment and vehicle immobilization were conducted in two counties.
Effectiveness of the Illinois .08 Law - (PDF Version) (posted 09-00)
The main objective of this study is to determine the effect of the .08 per se Blood Alcohol Concentration (BAC) law passed in July 1997, in Illinois on alcohol-related crashes and on the criminal justice system in the state.
Enhanced Sanctions for Higher BACs: Evaluation of Minnessota's High - BAC Law (posted 2/04/04) Also available in .pdf
This research study evaluated Minnesota’s "high BAC" law which mandates enhanced sanctions for DWI offenders with a blood alcohol concentration (BAC) of .20 or more.
Ethnicity and Alcohol-Related Fatalities: 1990 to 1994 (posted 09-00)
This report contains a preliminary analysis of just under 200,000 records of fatally injured road users drawn from the 1990 to 1994 Fatality Analysis Reporting System (FARS) produced by the National Highway Traffic Safety Administration (NHTSA). The analysis of ethnic factors in fatal crashes was made possible by the recent matching of death certificate data provided by the National Center for Health Statistics (NCHS) with the FARS cases.
Evaluation of the Austin Police Department DWI Enforcement Unit (posted 11/13/2003)
This report documents Austin, Texas' DWI enforcement unit and the benefits they've seen in increasing DWI arrests and decreasing alcohol-related fatalities.
Evaluation of a Full-Time Ride Service Program Aspen, Colorado's Tipsy Taxi Service
This report summarizes a study of Aspen Colorado's Tipsy Taxi ride service program. This service, which provides a free ride home for persons who are too intoxicated to drive, has been in place since December 1983. Funded through donations from the community, this program is available 365 days a year, 24 hours per day. The program is distinctive in that it has been operating for over sixteen years and is self-sustaining. An examination of injury crashes as a proxy of alcohol-related crashes revealed a significant reduction associated with implementation of the program. It is argued that a year-round alternative transportation program is an important component of a comprehensive anti-DUI countermeasure program which should also include deterrence components such as public information, enforcement, and sanctioning.
Evaluation of Enhanced Sanctions for Higher BACS: Summary of States’ Laws (posted 03/01/01)
During the period 1982 through 1996, the U.S. population increased by 15 percent; the number of licensed drivers increased by 20 percent; vehicle miles driven increased by 56 percent; and the number of non-alcohol-related traffic fatalities increased by 32 percent. Remarkably, the number of alcohol-related fatalities decreased 37 percent from 1982 to 1999.
Evaluation of Use and Lose Laws (posted 08-01)
"Use and Lose" typically describes laws that authorize driver licensing actions against people using or in possession of illicit drugs, and against young people drinking, purchasing or in possession of alcoholic beverages. Use or Lose means that if you use alcohol or drugs, you lose your license. This study examined the effects of Use and Lose laws in Pennsylvania and Missouri. In Pennsylvania, the findings suggest that license actions taken against this group lead to fewer subsequent violations and crashes. There was not a sufficient enough sample in Missouri to draw conclusions.
Evaluation of A Day Reporting Center for Repeat DWI Offenders
This research report describes and evaluates the effectiveness of a Day Reporting Center (DRC) in Phoenix, Arizona in reducing the DWI recidivism of repeat DWI offenders. The study found that the DRC program was no more effective in reducing recidivism than was a standard probation program. However, other measures of effectiveness yielded more positive results.

Evaluation of Alternative Programs for Repeat DWI Offenders (hs808493.pdf, 678K,posted 06-97)
This report describes a study to determine the effectiveness of two alternative sanction programs: Intensive Supervision Probation and Electronic Monitoring.
Evaluation of An Individualized Sanctioning Program For DWI Offenders Also available in .pdf
The statewide recidivism of two groups of convicted Georgia DWI offenders was studied. One group (the test group) was convicted and sentenced in a court in which the sentencing judge devoted considerable time and effort to crafting sentence packages tailored to the needs of individual offenders. The components of the sentence packages were selected from a wide range of traditional and alternative sanctions. The second group (the comparison group) was convicted and sentenced in another court in a nearby county where the policy was to impose generally only the minimum sentences mandated by state law.
Evaluation of Changes in New Mexico's Anti-DWI Efforts Also available in .pdf
This report examines the impact of New Mexico's omnibus anti-DWI legislation introduced in 1993-1994. As New Mexico also initiated an extensive statewide DWI checkpoint in that same time frame, it was not possible to separate the effectiveness of the laws versus the enforcement program. However, the overall effect of the package of new laws combined with the enforcement program was analyzed, finding a decrease in drunk driving fatal crashes of 19%.
Evaluation of Checkpoint Tennessee: Tennessee's Statewide Sobriety Checkpoint Program
This report documents the "Checkpoint Tennessee" program - - a statewide sobriety checkpoint program. In one year, Tennessee conducted almost 900 highly publicized DWI checkpoints, compared to the typical 10 to 15 that had been conducted in previous years. The study indicated a 20% reduction over the projected number of impaired driving fatal crashes what would have occurred with no intervention. This effect was still present 21 months after the initial year.
Evaluation of Female Driver Responses to Impaired Driving Messages ( posted 01-01)
Examination of DWI Conviction Rate Procedures
This research study examined how various jurisdictions across the country compute their DWI conviction rates. Although it seems like there would be an obvious and standardized method, in reality, various methods are used, making comparisons between jurisdictions difficult. The objective of this study was to document if different formulas are used, determine the positives and negatives of different approaches, and recommend a conviction rates formula. (Also Available in PDF)
Examining the Effectiveness of Utah's Law Allowing for Telephonic Testimony at ALR Hearings (posted 10-14-03)
Although the benefits of an Administrative License Revocation (ALR) law are numerous, in some jurisdictions there are also issues that make the process cumbersome and ineffective. In 2000, Utah enacted a law to address a problem they were having their ALR law. This study examines Utah's use of telephonic testimony at ALR hearings.

[ GI ]

Identification and Referral of Impaired Drivers Through Emergency Department Protocols(posted 04/11/2002)
The objective of this study was to determine the efficacy of an emergency department-based intervention program for identifying and referring persons at high risk of alcohol abuse or alcohol dependence to substance abuse treatment programs. The results indicated that high-risk patients who receive an intervention for alcohol problems in the emergency department following a motor vehicle crash were more likely to seek a formal evaluation for alcohol problems than those patients treated under the current standard of care who receive no ED intervention.

[ J-L ]

Legislative History of .08 Per Se Laws (posted 10/28/2001)
This study examined the strategies used to pass .08 BAC legislations in four states. The report notes the problems that were faced and how obstacles were overcome. The study also looked at two states that attempted, but were not able (at the time of the study), to pass .08 laws.

[ MO ]

Motivating Anti-DWI Behavior Using Existing Values (values.pdf, 541K, posted 03-96)
Despite progress in reducing alcohol-impaired crashes,the drunk driving problem won't be solved until society changes its beliefs and attitudes towards DWI. This study collected data to determine which things were most valued in respondents' lives. The report includes suggestions for anti-DWI countermeasures based on peoples' existing values.

Since 1991, the National Highway Traffic Safety Administration has conducted a nationally representative telephone survey every two years to measure the status of attitudes, knowledge, and behavior of the general driving age public about drinking and driving. The Gallup Organization conducted interviews with a national sample of 6,002 persons in the United States between November 8 and December 23, 2001. Volume I: Summary Report presents a top line summary of respondents' attitudes and behavior on various topics related to drinking and driving. Volume II: Methods Report describes the methods used to conduct the interviews and analyze the data. It also contains a copy of the questionnaire. Volume III: Findings Reports is not yet posted but will provide a more detailed set of analyses. (posted 06-19-03) National Survey of Drinking and Driving Attitudes and Behaviors, 2001 (Traffic Techs)

Observational Study of the Extent of Driving While Suspended for Alcohol-Impaired Driving (posted 10/28/02)
This is an observational study to determine the extent of driving on a license suspended for DWI. Offenders with suspended licenses were observed in Milwaukee, Wisconsin and Bergen County, New Jersey. Of subjects observed traveling in some way while suspended, 88% of Milwaukee subjects drove, compared to 36% of Bergen County subjects. Focus groups were conducted at each site to provide additional data. \

On DWI Laws in Other Countries

Much of the progress that has been made in impaired driving in the last decade or more has been facilitated by lessons learned from other countries. It is therefore both timely and appropriate for the National Highway Traffic Safety Administration to sponsor a systematic effort to gather information about impaired driving laws from countries around the world. The intent of this effort is to contribute to our understanding of impaired driving countermeasures and of how the current situation in the United States compares to other countries.

[ PR ]

Problems and Solutions in DWI Enforcement Systems
This study examined the DWI enforcement process from on-road detection, through the arrest process, to court proceedings, and sanctioning. The study included interviews with law enforcement officers, prosecutors, and judges across the country, and in-depth site visits to document various enforcement strategies. The purpose of the study was to identify loopholes in the enforcement system where offenders escape detection, arrest, conviction, or punishment, and to identify possible solutions.

Racial & Ethnic Group Comparisons National Survey of Drinking and Driving - Vol I: Findings (posted 09-00) Also available in .pdf
This study examines differences in drinking and driving attitudes and behaviors among diverse groups (i.e., Whites, Blacks, Asian, American Indian/Eskimo) by pooling data from NHTSA's 1993, 1995, and 1997 national surveys on drinking and driving.
Racial & Ethnic Group Comparisons National Survey of Drinking and Driving - Vol II: Methods Report (posted 09-00) Also available in .pdf
This volume presents the methods for gathering and analyzing data from these surveys.

Relative Risk Of Fatal Crash Involvement By BAC, Age, And Gender (posted 09-00)
"This study estimated age and sex specific relative risk of fatal crash involvement as a function of BAC based on logistic regression analyses of FARS combined with exposure data from The 1996 National Roadside Survey. Results showed that drivers with non-zero BACs below .10, and 16-20 year old male drivers below .08 BAC pose substantially elevated risk both to themselves and other road users."

[ S-U ]

Special Testing for Possible Carry Over Effects Using the Intoximeters, Inc. Alco-Sensor IV at 10 degrees Celsius. (posted 08-13-02)
This report describes special laboratory testing for possible alcohol carry over effects from one test to another using the Intoximeters, Inc. Alco-Sensor IV at 10 degrees Celsius. The results show that the possibility for carry over effects must be addressed when operating at low ambient temperatures. However, the potential for carry over can be easily eliminated by using procedural controls, such as performing an air blank before the test, or by testing two separate breath samples and/or by using a warm air flushing of the breath tester airway.

State of Knowledge of Alcohol-Impaired Driving: Research on Repeat DWI Offenders Also available in .pdf
The report reviews the scientific literature since 1990 about drivers who have been convicted more than once of driving while impaired by alcohol (DWI). The report covers the role of such drivers in alcohol-related crashes, their characteristics, and the nature and effectiveness of countermeasures designed to reduce their alcohol-crash involvement.

State of Knowledge of Drug-Impaired Driving report (posted 12/11/03)
This literature review covers scientific studies on drugged driving published since 1980. Over 300 documents were reviewed, including research from other countries. The report includes the detection and measurement of drugs in drivers, experimental research, epidemiologic research, and drug-crash countermeasures.

[ V-Z ]

Zero Tolerance Laws for Youth: Four States' Experience
This report summarizes the results of a project designed to describe and evaluate zero tolerance drinking driving laws for youth in four states. These laws prohibit driving by persons under 21 at a Blood Alcohol Concentration (BAC) over .00, .01, or .02 (depending on the state) in contrast to the levels set for adults at .08 or .10. The states studied were Florida, Maine, Texas and Oregon. Two of the states, Maine and Oregon, adopted such laws in the early 1980s and modified them in the mid-1990s to make them more stringent. Texas and Florida adopted their zero tolerance laws in the late 1990s.