Behaviors and Attitudes

NHTSA studies behaviors and attitudes in highway safety, focusing on drivers, passengers, pedestrians, and motorcyclists. We identify and measure behaviors involved in crashes or associated with injuries, and develop and refine countermeasures to deter unsafe behaviors and promote safe alternatives.

Interlock Data Utilization

This report summarizes findings on ignition interlock data is used for DWI offender monitoring and offender-related programs such as screening, assessments, and treatment for alcohol abuse problems. It describes the uses of interlock data, procedures for using interlock data, and challenges and issues related to using interlock data.

Marijuana-Impaired Driving – A Report to Congress

The report is to educate the public that drugs other than alcohol, including marijuana, are absorbed, distributed and eliminated from the body differently than alcohol. While BAC correlates closely with impairment, there is no such measure (e.g., THC) for marijuana that correlates with impairment. Thus, a BAC-equivalent impairment measure is not possible.

The Feasibility of Voluntary Ignition Interlocks as a Prevention Strategy for Young Drivers

Young drivers are at greater risk for alcohol-related crash deaths than any other age group, and there has been only limited progress. One innovative possibility that has not yet been tried for most young drivers is the implementation of a voluntary alcohol ignition interlock program as a preventative approach. This study examined its feasibility by discussions conducted in 2010 with ignition interlock manufacturers and service providers, insurance companies, community groups, parents, teens and young adults. Finally, ignition interlock recorder data on users 16 to 26 years old were examined, and a web survey with parents of voluntary users and voluntary users themselves was analyzed.

Determining the Effectiveness Of Flexible Checkpoints

The objectives for this project were to (a) determine how flexible checkpoints are being used in the United States; (b) identify agencies that use flexible checkpoints to document problems or concerns they’ve found, and to determine and document solutions that could be used by other agencies that implement flexible checkpoints; and (c) determine the effectiveness of flexible checkpoints in one site.

Older-Driver Foot Movements

This study explored how drivers 60 and older control the accelerator and brake while driving and parking, advancing an earlier study about pedal misapplication crashes. An instrumented vehicle on a test route in actual traffic measured foot movement and position affecting possible pedal error. Participants included 6 drivers with peripheral neuropathy of the feet, 2 with hip replacements, and 18 older but healthy drivers. Researchers also documented participants’ functional abilities such as leg functional reach and anthropometries such as height and femur length to determine whether these factors related to pedal control. Drivers with medical conditions scored significantly poorer than the normally aging drivers while parking. Poor vehicle fit was significantly related to functional ability.

Examination of the Legalization and Decriminalization of Marijuana on the DWI System: Highlights from the Expert Panel Meeting

In accordance with the MAP-21 Act, NHTSA and GHSA convened an expert panel to study recreational and/or medical marijuana laws and their effect on driving, including law enforcement, prosecutors, judges, probation, toxicologists, and highway safety officials. The panel identified changes to the DWI system following enactment of laws legalizing and/or decriminalizing marijuana for medical and/or recreational purposes; identified lessons learned; and found measures that should be used to evaluate these laws and their impact on traffic safety and the DWI system.

Examination of the Feasibility of Alcohol Interlocks for Motorcycles

In 2011 some 30 percent of the 4,612 motorcycle operators involved in fatal crashes had blood alcohol concentrations (BACs) of .08 g/dL or higher. Although alcohol ignition interlocks are a common sanction to deter impaired driving, they are not typically used on motorcycles. This report reviews information on alcohol ignition interlocks to help determine whether they can be an appropriate DUI countermeasure when installed on motorcycles operated by convicted DUI offenders. The report summarizes issues of perceived liability, technical barriers, statutory or legislative barriers, and other factors related to this issue.

2013–2014 National Roadside Study of Alcohol and Drug Use by Drivers: Drug Results

This report is one of three that summarizes the results of the 2013–2014 National Roadside Study (NRS) of Alcohol and Drug Use by Drivers. The National Highway Traffic Safety Administration (NHTSA) contracted with the Pacific Institute for Research and Evaluation (PIRE) to conduct this study. This report (Volume 3) presents national prevalence estimates of drug-positive driving and alcohol-plus-drug-positive driving derived from the study, and compares them with the 2007 NRS, which was the first roadside study to estimate the prevalence of drug-positive driving in the Unites States. Another report (Volume 1) describes the sampling plan and data-collection methodology (Kelley-Baker et al., 2016). A third report (Volume 2) (Ramirez et al., 2016) presents the results for alcohol-positive driving.

Medical Review Practices For Driver Licensing Volume 3: Guidelines and Processes In the United States

This is the third of three reports examining driver medical review practices in the United States and how they fulfill the basic functions of identifying, assessing, and rendering licensing decisions on medically or functionally at-risk drivers. This volume updates the information presented in 2003 (Summary of Medical Advisory Board Practices in the United States). Medical Review/Driver Reexamination Department staff in 49 of the 51 State driver licensing agencies plus the District of Columbia responded to a survey designed to gather information about the driver medical review structure and processes in their jurisdictions. The first section of this report presents a 5- to 10-page narrative for each jurisdiction describing the organization of the medical review program; mechanisms used to identify drivers with medical conditions and functional impairments; procedures and medical guidelines used to evaluate drivers for fitness to drive; medical review and reexamination outcomes; appeals processes; availability of counseling and public information and education; outreach to law enforcement, medical professionals and others who may have concerns about a medically or functionally impaired driver; and administrative issues such as training of employees, and costs associated with medical review/reexamination. Following the State-by-State summaries, tables compare and contrast States’ responses to each survey question. This updated information may serve as a reference to State driver licensing agencies when updating their own guidelines, practices, and outreach to those who may refer drivers for medical review, by showing what works in other jurisdictions; and may promote practices that maintain public safety while allowing for personal mobility.

Evaluation of Responsible Beverage Service to Reduce Impaired Driving by 21- to 34-Year-Old Drivers

A number of studies have revealed that approximately half of intoxicated drivers had their last drink at a licensed bar or restaurant. This study evaluated an intervention that integrated outreach, responsible beverage service (RBS) training, targeted enforcement and, as necessary, corrective actions by law enforcement agencies. The immediate goal of the intervention was to reduce the practice of over-serving alcohol and serving alcohol to obviously intoxicated individuals in bars and restaurants. The long-term goal was to reduce driving while intoxicated (DWI) arrests and impaired driving crashes.

Changes to Puerto Rico Motorcycle Rider Law

This report describes effects of a 2007 motorcycle safety law enacted in Puerto Rico in terms of rider reaction to the law, safety effects, and the degree to which the law was enforced. The law introduced or expanded safety-related statutes including reducing the blood alcohol concentration per se illegal level for motorcycle riders from .08g/dL to .02g/dL; requirements for reflective vests at night and other protective gear at all times of day; daytime running headlights, and other safety-related measures.

Evaluation of the Washington Nighttime Seat Belt Enforcement Program

The Washington Traffic Safety Commission and NHTSA conducted a high-visibility Nighttime Seat Belt Enforcement (NTSBE) program in Washington. The two-year program followed the basic “Click It or Ticket” model by using highly visible enforcement combined with increased paid and earned media about the enforcement but applied its efforts during the nighttime rather than the daytime hours. The NTSBE program positively affected driver awareness, increased observed nighttime seat belt use, and did not decrease the daytime use rate.

Evaluating the Enforceability of Texting Laws: Strategies Tested in Connecticut and Massachusetts

This evaluation sought to determine the enforceability of texting laws and to test methods for enforcing these laws. Participating law enforcement agencies in Connecticut and Massachusetts demonstrated that a variety of enforcement strategies could be used to enforce texting laws, including spotter, stationary, and roving patrol strategies. Strategy variations involved using one- and two-officer patrols, uniformed and plain clothed officers, marked and unmarked patrol vehicles, and a variety of vehicle types, including SUVs, vans, pickup trucks, motorcycles, and cruisers. This evaluation gathered first-hand insights from the participating officers regarding their experiences enforcing texting laws. Key insights highlighted the importance of conducting officer training, holding roll calls focused on texting enforcement, engaging in pre-planning to ensure smooth operation of the strategies, creating partnerships with local and State enforcement agencies to multiply forces and maximize resources, and establishing leadership priority for conducting texting enforcement.

Medical Review Practices for Driver Licensing Volume 2: Case Studies of Medical Referrals and Licensing Outcomes in Maine, Ohio, Oregon, Texas, Washington, and Wisconsin

Second of three reports examining driver medical review practices in the United States and how they fulfill the basic functions of identifying, assessing, and rendering licensing decisions on medically at-risk drivers. This volume presents findings of case studies describing the referral sources, medical review requirements, and licensing outcomes in six States in 2012, Maine, Ohio, Oregon, Texas, Washington, and Wisconsin. Conclusions support recommendations that may increase appropriate referrals for medical review. improve the medical review process while maintaining individual and public safety and preserving mobility among those with declining functional abilities, and ensure licensing agency resources applied to medical review focus on drivers most needing to be medically reviewed and tested.

Evaluation of an Updated Version of the Risk Awareness and Perception Training Program for Young Drivers

Previous research suggests newly licensed teen drivers often fail to anticipate where unexpected hazards might materialize. One training program designed to address these apparent deficiencies in knowledge and skills that has shown promise in previous tests is the Risk Awareness and Perception Training (RAPT) program. This project updated RAPT using high definition video and computer simulations to create a more interactive and realistic program. Researchers evaluated the modified program’s impact on the behaviors of novice and experienced drivers through the use of a computer-based test and during on-road drives in live traffic on a pre-defined route. Both the novice and experienced driver RAPT-trained groups showed substantial improvement in performance from pre- to post-test with the RAPT trainees hitting almost all of the targets during the computer post-test. The performance differences extended to the eye-tracker data arising from the on-road drives. The RAPT-trained groups hit significantly higher numbers of total primary targets and percentages of targets compared to the control groups. The study also employed a “Think Aloud,” or commentary driving, data collection effort. This data collection approach did not reveal any performance differences among the training groups. This study also included a persistence measure using the computer assessment one month after training. Results showed the RAPT-trained groups’ target hit rates decreased from the initial post-test to the persistence measure but remained above their baseline hit rates and above the control groups’ persistence measure hit rates. Taken together, the results suggest the RAPT revision represented a significant improvement over the previous versions in terms of realism with a similar impact on driver behaviors as measured by a computer assessment and through the use of eye-tracking in a live traffic environment.

Expanding the Seat Belt Program Strategies Toolbox: A Starter Kit for Trying New Program Ideas (DOT HS 812 341)

Researchers examined behavioral-change strategies proven effective in education, healthcare, advertising as possible approaches to increase seat belt use. This report is the result, a "starter kit" of ideas of varying levels of readiness so occupant protection programmers can use them in seat belt programming across the country. Five strategies include high school service-learning programs, hospital discharge programs, targeted online advertising, online learning and e-learning, and product/message placement.

More Cops More Stops: Evaluation of a Combined HVE Program in Oklahoma and Tennessee (DOT HS 812 337)

This report evaluates the “More Cops More Stops” combined enforcement program in Oklahoma and Tennessee, letting the traffic safety community make better informed programming decisions. This evaluation provides little evidence to support the continued use of MCMS to enhance the effect of CIOT and DSOGPO.

The Effect of High-Visibility Enforcement on Driver Compliance With Pedestrian Right-of-Way Laws: Four-Year Follow-Up (DOT HS 812 364)

This study is a follow-up to a previous study entitled High-Visibility Enforcement on Driver Compliance With Pedestrian Right-of-Way Laws. The objective was to determine the extent to which the observed increases in driver yielding obtained in the previous study persisted over a follow-up period of nearly four years after the high-visibility enforcement intervention program ended.

2013-2014 National Roadside Study of Alcohol and Drug Use by Drivers: Alcohol Results

This is 1 of 3 reports on our 2013-2104 National Roadside Survey – this report focuses on the Alcohol Results. The results showed a continuing reduction in alcohol-positive drivers on weekend nights – to 8.3% during our study. The results were announced during an event in early 2015.

Drug and Alcohol Crash Risk: A Case-Control Study

This study used a “case-control” design to estimate the risk of crashes involving drivers using drugs, alcohol or both obtaining 10,221 breath samples, 9,285 oral fluid samples, and 1,764 blood samples from more than 3,000 crash drivers and 6,000 control drivers. Crash risk estimates for alcohol indicated drivers with BrACs of .08 g/210L is 3.98 times that of drivers with no alcohol.

Medical Review Practices For Driver Licensing Volume 1: A Case Study of Guidelines and Processes in Seven U.S. States

This is the first of three reports examining driver medical review practices in the United States and how they fulfilled the basic functions of identifying, assessing, and rendering licensing decisions on medically at-risk drivers, documenting strengths and weaknesses of a variety of approaches. This report presents the methods used to group the diverse medical review practices across the 51 driver licensing agencies into four broad medical review structures, describes selection of States for case study, and identifies strengths and weaknesses associated with each of the four medical review structures. The seven States were Maine, North Carolina, Texas, Wisconsin, Ohio, Washington, and Oregon.

Evaluation of a Rural Seat Belt Demonstration Program in Florida, Georgia, and Tennessee

Three southeastern States initiated high-visibility enforcement campaigns to address lower seat belt use in their rural areas than in non-rural areas. Florida, Georgia, and Tennessee conducted four waves of intensified enforcement and media from November 2008 to May 2010. The May campaigns were conducted just prior to the national Click It or Ticket campaigns. Combining activity, awareness and usage data from all three States, there was a significant positive correlation between media expenditures and awareness of rural seat belt messages. Two awareness indices correlated highly with usage and achieved statistical significance: awareness of rural seat belt messages and perceived risk of a ticket for not buckling up. While the significant correlations between awareness measures and belt usage suggest that the message got through to drivers, comparison of changes in belt use in the RDP versus the control areas produced mixed results. Seat belt usage increased significantly in the targeted rural areas of all three States, but it also increased at about the same rate in the control areas in two of the States.

Video and Non-Video Feedback Interventions for Teen Drivers

In-vehicle feedback technologies help parents teach their adolescent drivers. While feedback technologies have been shown to reduce some risky driving behavior, teens and parents’ privacy concerns deter some families from using them, especially technologies that include video. This study evaluated two similar technology-based systems, one with and one without video, to determine how much they reduced unsafe driving behavior in newly licensed teen drivers.

Marijuana, Other Drugs, and Alcohol Use by Drivers in Washington State

In Washington State legal sale of marijuana began July 8, 2014. A voluntary, anonymous roadside study was conducted to assess the prevalence of drivers testing positive for alcohol and other drugs including marijuana on Washington’s roads. Data was collected in three waves, before implementation of legal sales, about 6 months after implementation, and one year after implementation. Of almost 2,500 participants, 14.6 percent of drivers, 19.4 percent of drivers, and 21.8 percent of drivers were THC-positive in Waves 1, 2, and 3, respectively.

2013–2014 National Roadside Study of Alcohol and Drug Use by Drivers: Methodology

This report describes the methodology for the National Roadside Study (NRS), a national field study to estimate the prevalence of alcohol-, drug-, and alcohol-plus-drug-involved driving primarily among nighttime weekend drivers, but also daytime Friday drivers.

Functional Outcomes for Older Adults Injured in a Crash

This report explores health and quality-of-life impacts of crashes among older (65+) and middle-aged (40-55) occupants. Analyses indicated the injured people had long-term health decrements following the crashes, and that older and middle-aged injured occupants showed continuing health decrements approximately 15 months following the crashes. Although both groups showed similar physical effects, middle-aged people showed greater quality-of-life decrements. These findings demonstrate the long-term implications of injury crashes and therefore highlight the need for crash avoidance and mitigation countermeasures.

Survey of DWI Courts

NHTSA conducted a web-based survey of DWI Courts and DWI/Drug Courts (court programs that handle both DWI and drug offenders) in April/May 2015 in order to obtain detailed information on how DWI Courts were operating. NHTSA conducted the survey in collaboration with the National Center for DWI Courts, who alerted State Drug Court Coordinators to the survey, supported NHTSA webinars that described the survey, and provided NHTSA with contact information for the court programs. A total of 156 courts responded to the survey from a contact list of 473.

Evaluation of Kansas and Missouri Rural Seat Belt Demos

Research has shown that seat belt use is lower in rural areas of the United States, which may be one reason fatalities are higher in these areas than in urban area. NHTSA sponsored two State-level demonstration projects intended to increase seat belt use in rural areas of Kansas and Missouri. During the study, Kansas and Missouri had secondary seat belt laws. Kansas used multiple media and enforcement waves, and Missouri employed a month-long media and enforcement campaign. Evaluations demonstrated increases in seat belt usage in many of the rural counties participating in the project, but some counties showed no change or even a decrease in seat belt use. Kansas showed an overall increase in seat belt use, from 61 to 70 percent use after the second intervention. Missouri showed increases in belt use in some of the 10 counties, though offset by decreases or no change in the other counties. Results support the conclusion that supplemental efforts of the demonstration projects produced positive results in the target counties and also benefited the total occupant protection programs in the State.

Advancing Pedestrian and Bicyclist Safety: A Primer for Highway Safety Professionals

This primer for highway safety professionals is a reference for integrated and improved pedestrian and bicycle safety, summarizing the most promising infrastructure and behavioral programs addressing specific safety problems and highlighting how to implement these approaches. It identifies opportunities for agency collaboration and funding, and offers real-world examples of how States and local jurisdictions address pedestrian and bicycle issues. It includes descriptions of key concepts and definitions of common terms and acronyms used in pedestrian and bicycle safety issues.

System Analysis of Automated Speed Enforcement Implementation

This survey of U.S. jurisdictions with Automated Speed Enforcement (ASE) programs examined protocols and practices in ASE deployment and implementation as well as the alignment of the programs with NHTSA guidelines. Differences between older and newer ASE programs were related to the enabling legislation and technology used. Speed management plans are important components of speed enforcement. Of the agencies responding to the survey, 53% had no plan for reducing speeding, while 34% had a plan, and 11% did not know if they had one. ASE program alignment with the NHTSA guidelines varied. Most agencies (63%) were unaware of the ASE guidelines prior to participating in the study.

Effect of Electronic Device Use on Pedestrian Safety: A Literature Review (DOT HS 812 256)

This literature review summarizes pedestrian distraction, driver distraction, and pedestrian-vehicle interactions. The findings further divide into subsections on study methodologies such as naturalistic observations, simulation, laboratory, or crash database analysis. A few studies investigate electronic device use by pedestrians and drivers and the effect on pedestrian safety, although with fewer naturalistic observation studies. Most previous studies focus primarily on cell phone use, but the discussion regarding other types of electronic devices is missing. The review illustrates the need to conduct naturalistic observations of the effect of electronic device use on pedestrian distraction and safety.

Motivations for Speeding – Additional Data Analysis

This study examined naturalistic driving data from 164 drivers. It defined speeding in terms of speeding episodes and examined the influence of situational factors on different types of speeding. Analyses identified several types of speeding: Speeding that occurs around speed-zone transitions, incidental speeding, casual speeding, cruising speeding, and aggressive speeding. Analyses also identified four driver types: Unintentional Speeders, Situational Speeders, Typical Speeders, and Deliberate Speeders. The types of speeding and driver types identified occurred across all demographic groups. Findings on the general riskiness of different types of speeding and location-specific characteristics and driving environment effects on speeding are reported.

Evaluation of the Safety Benefits of the Risk Awareness and Perception Training Program for Novice Teen Drivers

This project evaluated the impact of the Risk Awareness and Perception Training (RAPT) program on young driver crashes and traffic violations. A total of 5,251 young drivers 16 to 18 years old were recruited after passing on-road driving exams at six California DMV licensing offices. They were assigned to a group who completed the RAPT program or a comparison group who received pre-tests but did not receive any training. Their crash and violation records were tracked for 12 months post-licensure. Analyses showed substantial improvements in trainee performance. Crash analyses did not show an overall main effect for treatment, but there was a significant treatment by sex interaction effect. Analyses were then conducted for males and females separately to explore this interaction. The results showed a significant treatment effect for males but not for females. RAPT-trained males showed an approximately 23.7% lower crash rate relative to the male comparison group. For females, the RAPT group had an estimated 10.7% higher crash rate than the comparison group, but this increase was not statistically significant.

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