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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.

163 Results

Pedestrian/Bicyclist Safety in Numbers Program Evaluation

Safety in Numbers -- SIN -- is the idea that increased walking and biking are associated with safer road environments for pedestrians and bicyclists. Specifically, as the number of people who walk and bike increase, pedestrian and bicyclist crashes will increase at a lower rate. As more agencies are focusing on ways to reduce crashes, including efforts such as the Road to Zero or Vision Zero, measures that might increase pedestrian and bicycle crashes are a concern. SIN would help to provide the understanding of potential outcomes associated with increases the number of people walking and bicycling. A literature review conducted as part of this project provides a detailed history of the SIN concept, including when the term was first coined and challenges to and refinement of the concept. This is a companion report to Report No. DOT HS 813 279 published in June 2022.

Reducing Distracted Driving Among Adults: Child-to-Adult Interventions

Distracted driving is a problem for drivers and their passengers. Several programs exist to reduce the distracted driving habits of people who are already drivers. However, there are few programs that teach children before they become drivers, especially in the elementary school, how to intervene with a driver (usually a parent) who is distracted and none that have been evaluated. Only one program was identified that developed both a lesson to teach elementary school children how to intervene with a distracted drivers and an evaluation of the lesson. The COVID-19 pandemic made it necessary to pivot from the classroom to online and to broaden the program to include high school as well as elementary school students. Among high school students, the program produced a statistically significant increases in students’ knowledge of distracted driving and what they need to say to their drivers to refrain from driving distracted, statistically significant increases in the frequency of intervening with parents and passengers (but not friends), and a reported decrease in distracted driving of their parents and friends.

Estimated Contribution of Peak-Hours Non-Commercial Vehicle Traffic to Fatality Rates, Research Note, Traffic Safety Facts

This Traffic Safety Facts Research Note explores the relationship between the decline in vehicle miles traveled (VMT) associated with the COVID-19 pandemic and the increased fatality rate observed for 2020. It hypothesizes that the fatality rate relative to previous years is due in part to a decrease in peak-hours (i.e. 6–9 a.m., 3–6 p.m.) non-commercial vehicle traffic – that is, a decrease in commuting. To draw comparisons with 2020 the author use the most recent National Household Travel Survey, Fatality Analysis Reporting System, and FHWA VMT data to estimate separate peak and non-peak, non-commercial vehicle fatality rates for 2017. The estimated peak-hours non-commercial vehicle fatality rate for 2017 was .5 per 100m VMT, while the non-peak hours non-commercial fatality rate was 1.27 per 100m VMT. Excluding peak-hours non-commercial vehicle traffic, 2017 had an overall fatality rate of 1.48 per 100m VMT. The fatality rate for 2020 was 1.34 per 100m VMT. The author therefore conclude that decreased peak-hours non-commercial vehicle traffic associated with the COVID-19 pandemic, stay-at-home orders, and increases in remote working contributed to 2020’s increased fatality rate relative to previous years.

Understanding and Using New Pedestrian and Bicycle Facilities

Research has explored the benefits of innovative pedestrian and bicycle facilities, but it is unclear how pedestrians and bicyclists learn to properly use them. This report provides information on new pedestrian and bicycle treatments and (1) the behavior and knowledge of pedestrians, bicyclists, and drivers traversing through, on, and around the new facilities, and (2) law enforcement activity around the facilities. A systematic literature review as well as a review of current practices in outreach was conducted.

Safety in Numbers: A Literature Review

In pedestrian and bicyclist safety, Jacobsen’s 2003 “Safety in Numbers” (SIN) theory posits an inverse relationship between the extent of walking and bicycling and the probability of motorist collisions. This literature review summarizes SIN research, identifying implications of the work chronologically,  developing the SIN concept and subsequent work testing and expanding the theory. It considers study fields and areas of practice including engineering, planning and land use, sociology, psychology, education, public health, enforcement, human factors, and others. This breadth was especially important due to wide audience who may apply this review results to their future practice. These include State Highway Safety Offices, national organizations interested in the SIN topic, constituents from the FHWA, planners, engineers, educators, advocacy groups, policymakers, State DOTs, metropolitan planning organizations, and roadway users -- motorists, pedestrians, bicyclists -- and law enforcement.

Risk Factors for Young Drivers in Fatal and Non-Fatal Crashes: Supplementary Report

This is supplementary report accompanies the report titled, Risk Factors for Young Drivers in Fatal and Non-Fatal Crashes.

Risk Factors for Young Drivers in Fatal and Non-Fatal Crashes

This report analyzed data from young drivers 16 to 20 years old from the Fatality Analysis Reporting System (FARS) years 2013 to 2017, and from the second Strategic Highway Research Program’s Naturalistic Driving Study (SHRP2 NDS). The data permitted a comparison of trends between age and amount of driving experience for a similar range of variables. Although young driver risk appeared to decline with increasing age, young drivers were at higher risk than 35-year-olds for most factors. Some situations were particularly risky for young drivers relative to 35-year-old and relative to other kinds of situations. The results from this study may be useful for developing graduated driver licensing as well as driver education content.

Synthesis of Studies That Relate Amount of Enforcement to Magnitude Of Safety Outcomes - Technical Appendix

This is the Technical Appendix for the Synthesis of Studies That Relate Amount of Enforcement to Magnitude Of Safety Outcomes report, DOT HS 812 712-A.

Synthesis of Studies That Relate Amount of Enforcement to Magnitude Of Safety Outcomes

The National Cooperative Research and Evaluation Program (NCREP) identifies and funds research and evaluation projects that improve and expand State highway safety countermeasures. One such topic is measuring the impact of various amounts of traffic enforcement on changes in safety outcomes. The project team identified 80 relevant studies for inclusion in the synthesis. Current literature only supported findings related to occupant protection enforcement. No relationship between levels of enforcement and safety outcomes could be identified for distracted driving, alcohol-impaired driving, speeding, or aggressive driving. However, for all targeted behaviors, the enforcement campaigns evaluated were effective in improving safety outcomes even though the combination of these evaluations could not provide sufficient evidence to establish a relationship between the level of resources used and the magnitude of the safety improvement.

Research on Older Adults’ Mobility: 2021 Summary Report

This report summarizes a meeting to spotlight research on older adults’ mobility held in January 2021– dubbed ROAM, Research on Older Adult Mobility – provided a forum to share news of completed research, report on the progress of ongoing studies, and highlight priorities for future work. Participants included medical professionals, occupational therapists, State DMV officials, mobility service provider specialists, automated driving system/advanced driver assistance system experts, and other academic and private sector research professionals. The meeting supported equity in traffic safety as it addressed disparities faced by older adults.