Research & Evaluation
Behavioral Research
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.
| Title | |
|---|---|
Examining Instrumented Roadways for Speed-Related ProblemThis project evaluated efforts by the Stafford County, Virginia, Sheriff’s Office to reduce speeding on roadways. Researchers coordinated to implement countermeasures on corridors with safety concerns where speed was a factor. Speed and enforcement data were collected to look at the impacts of the enforcement efforts. From this, the SCSO was able to make decisions on where countermeasures would be applied and what countermeasures would be implemented, including deputy presence with on-site enforcement, decoy cars, speed trailers with digital feedback signs, and changeable message signs. The SCSO also used social media to release public service announcements about the safety campaigns. Decoy cars proved to be the most successful activity that led to drivers reducing their speeds for more than a day. Speed trailers and deputies on-site issuing citations were also effective, but seemed to be localized. The study found the number of speeders to be a statistically significant predictor of crashes and showed that traffic volumes can increase without a concurrent increase in crashes if the increased volume is made up of non-speeders. |
DOT HS 813 467 |
Increasing Safety Belt Use Amongst Rural PopulationsThis 12-month demonstration project focuses on increasing seat belt use in two test locations, Bingham County, Idaho, and Rapides Parish, Louisiana. The project relies on a multifaceted approach consisting of sustained publicity and police enforcement. A technical assistance guide was used to motivate and assist law enforcement agencies to engage rural community members on the importance of wearing seat belts. The program consisted of contact with seat belt violators and sustained messaging. Results were mixed. Officer engagement with non-compliance rose in both locations, but messaging efforts were hampered by the COVID-19 pandemic and staff shortages. Rapides Parish showed modest improvements in belt use, but Bingham County did not. During debriefing, local agency representatives were confident that the program would be more successful if carried out in more normal circumstances. |
DOT HS 813 442 |
Research on Older Adults’ Mobility: 2023 Meeting Summary ReportThis report describes a meeting held to spotlight research on older adults’ mobility (ROAM). Participants shared news of completed research, reported on the progress of ongoing studies, and highlighted priorities for future work. ROAM 2023 included general and breakout sessions devoted to the safety implications of limited-term license renewal policies, transportation options for rural and small communities, older pedestrian crashes, promoting older driver safety to State agencies and providers, a national volunteer driver center, safety implications of older drivers’ vehicle choices, and the CarFit program. Some information reported on events and research discussed in last year’s meeting, known as ROAM 2022. |
DOT HS 813 457 |
Exploring the Impact of Select Speed-Reducing Countermeasures on Pedestrian and Bicyclist SafetySpeed is a contributor to both crash frequency and crash severity. This project explored efforts to reduce speed and evaluated their effectiveness in improving safety for pedestrians and bicyclists. Phase 1 was a program scan that identified countermeasures in use throughout the United States. Based on the scan, the team evaluated automated speed enforcement and road conversions in five municipalities to explore their impact on motor vehicle related pedestrian and bicyclist crashes. Phase evaluated safety benefits of a select group of temporary road conversions implemented in response to the COVID-19 pandemic. |
DOT HS 813 446 |
In-vehicle Drowsy Driving Detection and AlertingThis project evaluated the efficacy of two notifications, a lane departure warning (LDW) and a drowsiness notification with LDW (DN/LDW), on potential drowsy driving episodes during 4-hour overnight drives in a high-fidelity driving simulator with an incentive method designed to replicate the motivational tradeoffs common to drowsy driving. The combined DN/LDW, but not the LDW, was effective in reducing the frequency of lane departures and in reducing percentage of eyelid closure prior to lane departure events compared to baseline. There was no difference between the notification conditions and baseline with respect to the frequency or timing of breaks to rest. |
DOT HS 813 438 |
Designing a Study to Investigate Older Novice DriversDrivers 15 to 20 years old—many of whom were novice drivers—represented 8.5 percent of drivers involved in fatal crashes but only 5.1 percent of all licensed drivers in 2020. Graduated driver licensing (GDL) laws are the most effective behavioral countermeasure for young drivers. However, although an increasing proportion of young people are delaying licensure until 18 or older, few States currently apply the full GDL program to 18- to 20-year-old novice drivers, and little is known about the safety and driving habits of this group. In this project the research team developed a hypothetical naturalistic driving study to investigate research questions about the safety and driving exposure of younger (15.5 to 16.5 years old) and older (18 to 20 years old) novice drivers in the first year of unsupervised (independent) driving. |
DOT HS 813 413 |
Characteristics of State Law Enforcement Liaison Programs: Case StudiesThis project conducted follow-up case studies after a recent survey examining law enforcement liaison (LEL) program characteristics across the Nation. The survey identified the most important attributes that aid LELs in reaching their work goals. This project included the development of an interview guide, site selection, identifying LELs, discussions with the LELs, data collection, and analysis. There were seven topic areas: sponsoring organization involvement, staff and resource allocation, roles and responsibilities, performance measures, outreach, communication, and the COVID pandemic. Maintaining State Highway Safety Office interactions is important for grant administration, technical support, public outreach, and overall grant support. LELs noted it was important to recognize and be aware of how the current state of traffic enforcement culture affects their program goals and activities. |
DOT HS 813 392 |
A Systematic Review of Profiles of Speed and Lane Keeping for Driving Simulator DataThis project aimed to develop a profile of “normal” driving performance by identifying patterns in data collected by previous studies at the National Advanced Driving Simulator (NADS). To support this, a repository of control/baseline data was created that can also be used in lieu of collecting new data to support future studies. Data was mined from previous driving simulator research studies conducted at NADS on the NADS-1 and miniSim using predominately control/baseline scenarios, specifically scenarios devoid of driving under the influence, distraction events, and drowsiness. The repository includes study-specific data, including purpose of the study, sample population requirements, environment types, and driving variables collected along with demographic and simulator data. |
DOT HS 813 414 |
Building Community Support for Impaired Driving EnforcementImpaired-driving traffic crashes affect communities negatively across the United States. Research has confirmed the effectiveness of high-visibility enforcement (HVE) in reducing impaired-driving fatalities. This report describes a demonstration project to increase community support for law enforcement efforts to reduce alcohol-impaired driving in Joplin, Missouri. The Joplin Police Department convened community representatives and organizations to develop a 15-month plan to raise community awareness and support for year-round DWI enforcement including enforcement, media, and public outreach. During the enforcement, overall crashes decreased, and impaired-driving crashes remained stable when compared to the immediate pre-enforcement period. Although there were documented successes, an independent evaluation of the program found that there was not enough program activity to increase community support for sustained impaired-driving law enforcement efforts. |
DOT HS 813 338 |
Evaluation of Community-Oriented Enforcement Demonstration ProjectsThis project evaluated effectiveness of two law enforcement agencies’ use of data-driven approaches to traffic enforcement in Missouri and Oklahoma, supported by community-oriented policing to improve traffic safety and boost community support for traffic law enforcement. One focused on improving seat belt use and the other on reducing alcohol-impaired driving. Both 15-month programs began in 2018. Community-oriented enforcement implemented in these demonstrations was not effective at building community support nor increasing perceived risk of enforcement needed for high-visibility enforcement to be effective. |
DOT HS 813 291 |