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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.

Our recently published reports and research notes are listed chronologically below. To the right are additional resources including Traffic Techs.

151 Results

Effectiveness of Dynamic Speed Feedback Signs, Volume I and II

This two-volume report is a comprehensive, quantitative review of published research on the effectiveness of dynamic speed feedback signs (DSFSs) and presents evidence that DSFS can be effective in reducing mean speeds, 85th percentile speeds, and the percentage of drivers over the speed limit in a wide range of contexts. The clear majority of studies found significant reductions in speeds at the DSFS when the DSFS are activated across all types of vehicles and different installation locations. This publication, Volume II, presents the technical appendices and annotated bibliography. Volume I presents the literature review and meta-analysis.

Defining Contextual Variables Related to Seat Belt Use in Fatal Crashes

This report describes a study investigating some of the contextual and environmental characteristics of places that may influence seat belt use and, by implication, the lack of restraint in crash fatalities. In particular, on-premises businesses that sell alcohol for on-site consumption, off-premises businesses that sell alcohol for off-site consumption, and tourism locations were examined for potential relationships to the lack of restraint use in crash fatalities in the United States from 2012 to 2016.

Impact Analysis of Bicycle Safety Laws

Bicycling is increasingly popular, economical, environmentally friendly, and has cardiovascular benefits. Many States have enacted bicycle traffic safety improvement laws such as safe passing, promote safer practices among bicyclists such as mandatory helmet use, or treat bicyclists as a separate class of road user, as with the Idaho Stop law. The Impact Analysis of Bicycle Safety Laws documented a study of six laws (safe passing, mandatory helmet use, bicycling under the influence, where-to-ride, sidewalk riding, and the Idaho stop) to determine if States and communities should create separate laws to govern bicyclists, and if bicyclist-specific traffic safety laws protect them from motor vehicle crash injuries and fatalities.

National EMS Scope of Practice Model 2019: Including Change Notices 1.0 and 2.0

The President’s National Strategy for the COVID-19 Response and Pandemic Preparedness calls for immediate actions to support State and local efforts to enlist emergency medical services and firefighters to support vaccination efforts. The 2019 National EMS Scope of Practice Model Including Change Notices 1.0 and 2.0 adds intramuscular injection, vaccinations during a public health emergency, and nasal swab specimen collection to the scope of practice of EMS clinicians at the EMT and higher levels.

A Primer for Evaluating Underage Drinking and Driving Programs

This primer is a practical “how-to” guide for practitioners and researchers interested in evaluating underage drinking and driving programs. It distills program evaluation and provide guidance specific to underage drinking and driving. Components address barriers to program evaluation; how to address challenges unique to developing and evaluating underage drinking and driving programs; key elements to look for when searching for effective interventions or programs; models and theories grounded in both public health and psychology that can serve as a guide for developing, implementing, and evaluating interventions and/or programs; evaluation standards from the CDC framework that can support a quality evaluation and assist when prioritizing and/or choosing from the multitude of options at each phase of program evaluation; and how to obtain Institutional Review Board approval.

Update to Special Reports on Traffic Safety During the COVID-19 Public Health Emergency: Fourth Quarter Data, Research Note, Traffic Safety Facts

NHTSA is reviewing nationwide changes in traffic safety and observed behaviors caused by the COVID-19 public health emergency. This research note includes data through the end of the 2020 calendar year, updating earlier preliminary reports. The research note includes changes in travel patterns, rates of crash severity, and the prevalence of drugs and alcohol among seriously and fatally injured road users at select trauma centers.

Exploring the Predictive Validity of Drug Evaluation and Classification Program Evaluations

This report seeks to determine which combinations of drug-related signs and symptoms from the Drug Evaluation and Classification (DEC) protocol most efficiently and effectively predict the drug category or combination used by the subject. A sample of 2,261 DEC evaluations conducted on suspected drug-impaired drivers included cases involving specific drug categories and two-drug combinations commonly encountered by DREs. This study also examined how effectively the set of drug-related measures from the DEC procedure could distinguish drug-positive from drug-negative cases for two common drug categories (cannabis and CNS depressants) and the relative importance of clinical, behavioral and observational measures in predicting drug categories responsible for impairment. Thirteen drug-related indicators were found to significantly contribute to the prediction of drug category; 12 indicators contributed significantly to the prediction of drug combinations.

High-Visibility Enforcement: Assessing Change and Identifying Opportunities

In this study the research team interviewed nine officials from State Highway Safety Offices (SHSOs) to determine if they perceived a change in participation in or support for high-visibility enforcement (HVE) over the past decade. The research team also interviewed six SHSO or local law enforcement agency (LEA) officials to profile innovative strategies that States or LEAs are using to increase law enforcement participation in HVE. Most of the nine SHSO officials believed there has been a decrease in law enforcement participation in and support for grant-funded HVE activities over the last 10 years, and the SHSO officials identified several common challenges to participation in HVE. However, interviews with SHSO and LEA officials regarding innovative strategies being used to increase participation in HVE revealed possible solutions for these challenges.

Physical Fitness Training and Older Driver Performance and Exposure

This research hypothesized that participation in a structured exercise program by inactive adults 70 or older would result in improved road test performance and increased driving exposure (the amount and circumstances under which people choose to drive). Participants were randomly assigned to an exercise group (n=20) that involved activities including weight-bearing, resistance, or dance/movement elements, or a control group (n=10). The researchers assessed physical and cognitive status before and after training, and a certified driver rehabilitation specialist evaluated behind-the-wheel performance using a recognized road test. Treatment effectiveness was gauged in terms of “change scores” for road test performance and for multiple indices of driving exposure. Correlations between measures of physical/functional status and driving performance were weak or very weak.

Pilot Test of a Methodology for an Observation Survey of Motorcycle Personal Protective Equipment

This project addressed the need for information on use of motorcycle personal protective equipment (PPE), including the use of certified helmets, sturdy jackets and pants, over-the-ankle boots, and riding gloves. Although motorcycle safety advocates and safety programs encourage the use of PPE, the use rate is not well known or easily determined. This project sought to develop a methodology suitable for jurisdictions to use when seeking data on the motorcycle PPE usage, and to produce a valid assessment of PPE. The methodology was deployed in Florida across two rounds of data collection. The project outcome supports motorcycle safety programs and highway safety offices in their efforts to obtain information on the use rate of motorcycle safety gear.