RESEARCH

Cutting-edge research, tools, data, and resources—compatible with a Safe Systems approach—are developed and utilized by professionals and the public at large to better understand and address existing and emerging road safety issues.

Research objectives

These key CSCRS objectives outline the Center’s core approach to research:

Perform road safety research that explores core safety issues and transformational changes.
Develop research-driven tools, resources, and data sets to support problem identification and understanding.
Support development of programs, policies, and practices proven to reduce fatalities.
Disseminate research products and findings, reaching new and non-traditional audiences.

Completed Research Projects

Moving forward to meet ambitious safety targets requires a rigorous, conceptually driven and focused research agenda.

This portfolio includes summaries of completed research projects.

R1: Structures of stakeholder relationships in making road safety decisions

Principal Investigator – Seth LaJeunesse, University of North Carolina, Chapel Hill
Findings from this three-phase study suggest that Vision Zero and safe systems strategies can diffuse across U.S. cities in accelerated fashion. Further, though it will require more time before cities document significant improvements in road user safety, the organizational network analysis carried out in Phase III of this R1 project holds promise as an exploratory technique to employ toward identifying adaptive, resilient cross-sector partnerships.

R2: An enhanced systemic approach to safety

Principal Investigator – Offer Grembek, University of California, Berkeley
This report presents an enhanced systemic approach which consists of targeting blanket improvements at sites across a road network based on specific roadway features that are associated with a particular crash type.

R3: Implementing Safe Systems in the United States: Guiding principles and lessons from international practice

Principal Investigator – Eric Dumbaugh, Florida Atlantic University
This report examines the state-of-the-practice in Safe Systems. It is divided into two sections. The first examines the concept of Safe Systems, focusing on our emerging understanding of crash causation, as well as how this understanding may be applied to integrate safety considerations into transportation practice in the United States. The second presents a review of the practices of the four countries with the most established Safe Systems programs—Sweden, the Netherlands, Australia, and New Zealand—and details how each has structured their approach to road safety around Safe Systems principles.

R4: Completing the picture of traffic injuries: Understanding data needs and opportunities for road safety

Principal Investigator – Chris Cherry, University of Tennessee, Knoxville
In this study, we introduced a new approach to evaluate road safety that focuses on the home address of individuals (i.e., home-based approach) who were directly involved in traffic crashes instead of the location of the crashes (location-based approach).

R5: Traffic safety practices in U.S. cities: Survey and focus group results

Principal Investigator – Eric Dumbaugh, Florida Atlantic University
This study seeks to understand the state-of-the-practice for addressing safety in U.S. cities. It consists of a survey of the 150 largest cities in the U.S., by population size, as well as a focus group of individuals from cities recognized at being the forefront of addressing safety.

R6: Using advanced analytics to frame vulnerable road user scenarios with autonomous vehicles

Principal Investigator – Noreen McDonald, University of North Carolina, Chapel Hill
Connected and automated vehicle technologies can dramatically improve safety by reducing human errors, which contribute substantially (an estimated 94 percent) to roadway crashes.

R7: Development and evaluation of vehicle to pedestrian (V2P) safety interventions

Principal Investigator – Missy Cummings, Duke University
This research effort, the first to conduct a controlled experiment of crossing pedestrians in a field setting with smartphone-based alerts, demonstrated that in a group of 30 participants given smartphone aural and visual alerts of varying reliability while engaging in distracted walking, only 2% exhibited a tendency towards unsafe crossings, while 18% tended towards risky crossings.

R8: Development of resources to guide parents in helping teens learn to drive

Principal Investigator – Arthur Goodwin, University of North Carolina, Chapel Hill
North Carolina has led the way in policy efforts to address teen driver crashes with graduated driver licensing, which has reduced crashes by 38 percent among 16-year-olds and by 13 percent among 17-year-olds.

R9: Concept of operations for an autonomous vehicle dispatch center

Principal Investigator – Missy Cummings, Duke University
The purpose of the CONOPS will be to describe the operational needs and systems characteristics for the system.

R10: Machine learning tools for informing transportation technology design

Principal Investigator – Missy Cummings, Duke University
This project will investigate how machine learning techniques can be used to design countermeasures that improve system safety.

R11: The influence of the built environment on crash risk in lower-income and higher-income communities

Principal Investigator – Yanmei Li, Florida Atlantic University
While previous research has consistently identified income as a significant factor in understanding community-level crash risk, the results of this study suggest that income has a far more complex relationship to crash incidence than has been previously supposed.

R12: Emergency Medical Services (EMS) and the California EMS Information System (CEMSIS) Working Paper

Principal Investigator – David Ragland, University of California, Berkeley
This project addresses two California issues; one is to provide a more accurate picture of traffic injuries in California by utilizing medical data to fill in police crash reports. The second is to get a more accurate picture of emergency medical services response times.

R13: Shared mobility services and their connection to roadway fatalities

Principal Investigator – Noreen McDonald, University of North Carolina, Chapel Hill
This project will assess how technological change embodied by shared mobility services has and will impact road safety.

R14: Creating a CSCRS clearinghouse for bicyclist and pedestrian safety-related data, Phase I: inventory & framework

Principal Investigator – Krista Nordback, University of North Carolina, Chapel Hill
The National Pedestrian and Bicycle Data Clearinghouse has been developed to improve data for pedestrian and bicycle analyses in the United States.

R15: Integrating spatial safety data into transportation planning processes

Principal Investigator – Chris Cherry, University of Tennessee, Knoxville
Despite previous attempts to integrate road safety into planning models, one area that needs further attention is the safety of road users (instead of road entities) and how changes in travel patterns due to changes in transportation infrastructure and demographics affect the safety of road users.

R16: Opioids at the health and transportation safety nexus

Principal Investigator – Chris Cherry, University of Tennessee, Knoxville
This project will identify a system map for the linkage of prescription opioid and traffic safety data, as well as the generation of research questions that will contribute to further investigation.

R17: Strengthening existing and facilitating new Vision Zero plans

Principal Investigator – Kelly Evenson, University of North Carolina, Chapel Hill
Employing the recommendations and resources in this Guide can directly and positively impact the creation of new Vision Zero Plans and assist municipalities as they update existing Vision Zero Plans.

R18: Examining the Traffic Safety Effects of Urban Rail Transit: A Review of the National Transit Database and a Before-After Analysis of the Orlando SunRail and Charlotte Lynx Systems

Principal Investigator – Eric Dumbaugh, Florida Atlantic University
This study conducted a longitudinal analysis of light rail and streetcar safety in the United States for the period 2002-2017 using data obtained from NTD.

R19: Developing a taxonomy of human errors & violations that lead to crashes

Principal Investigator – Asad Khattak, University of Tennessee, Knoxville
This project will develop key elements of a Safe Systems framework by analyzing human errors and violations and their contributions to crashes; bringing together and analyzing behavioral, infrastructure/built environment, and vehicle, and data analytic features to find ways to reduce crashes and prevent injuries.

R20: Investigating the vulnerability of motorcyclists to crashes and injury

Principal Investigator – Asad Khattak, University of Tennessee, Knoxville
This study will focus on analyzing a unique database of motorcycle crashes, exploring how key risk factors vary by demographics and from one context to another, i.e., the settings in which motorcycle travel takes place.

R21: A systems approach to pedestrian safety, Phase II: Examining congestion pricing policies

Principal Investigator – Becky Naumann, University of North Carolina, Chapel Hill
The overall goal of this project was to develop a quantitative system dynamics simulation model that could be used as a learning tool to explore the pedestrian safety impacts of specific, current policy approaches in a defined U.S. setting.

R22: Using integrated data to examine characteristics related to pedestrian and bicyclist injuries

Principal Investigator – Katherine Harmon, University of North Carolina, Chapel Hill
This study seeks to provide a comprehensive examination of pedestrian motor vehicle crash injuries in North Carolina (NC) using linked crash and emergency department visit data for the period October 1, 2010 – September 30, 2015.

R23: Driver impairment detection and safety enhancement through comprehensive volatility analysis

Principal Investigator – Asad Khattak, University of Tennessee, Knoxville
By integrating and fusing multiple data sources including driver biometrics, vehicle kinematics and roadway/environment conditions in real-time, this project aims to generate useful feedback to drivers and warnings to surrounding vehicles regarding hazards.

R24: Developing a framework to combine the different protective features of a Safe System

Principal Investigator – Offer Grembek, University of California, Berkeley
This study explores what means are currently available to evaluate the cumulative ability of the system to protect street users.

R25: Advancing crash investigation with connected and automated vehicle data

Principal Investigator – Asad Khattak, University of Tennessee, Knoxville
This study seeks to leverage newly available Connected and Automated Vehicle (CAV) data to improve crash investigation procedures and obtain input from stakeholders, specifically law enforcement.

R26: Understanding micromobility safety behavior and standardizing safety metrics for transportation system integration

Principal Investigator – Chris Cherry, University of Tennessee, Knoxville
This project focused on exploring micromobility safety data and methods to improve injury surveillance.

R27: Safety testing for connected and automated vehicles through physical and digital iterative deployment

Principal Investigator – Subhadeep Chakraborty, University of Tennessee, Knoxville
In this CSCRS project, we seek to develop a comprehensive testing protocol specifically for Level 2 and 3 connected and automated vehicles by using a novel software and physical deployment platform that allows rapid iterative development.

R28: Reducing motorcyclist injuries: Engaging stakeholders to apply evidence-based countermeasures

Principal Investigator – Jerry Everett, University of Tennessee, Knoxville
Since motorcyclists are far more vulnerable than enclosed vehicle users on the road, they are more likely to get injured in a crash. While evidence-based countermeasures are available, this research aims to shorten the implementation cycle in the translation of research into practice.

R29: Factors and frames that shape public discourse around road user safety

Principal Investigator – Seth LaJeunesse, University of North Carolina, Chapel Hill
The purpose of this project was to uncover common framing and narrative devices used in covering traffic crash events in televised news.

R30: Urban freight and road safety: Trends and innovative strategies

Principal Investigator – Noreen McDonald, University of North Carolina, Chapel Hill
In this study we conducted a systematic review to identify last-mile delivery strategies and to determine how those strategies have been evaluated in the literature.

R31: Crash risk for low-income and minority populations: An examination of at-risk population segments and underlying risk factors

Principal Investigator – Diana Mitsova, Florida Atlantic University
This study examines pedestrian and cyclist crashes occurring in lower-income areas in Florida’s Broward, Palm Beach, and Miami-Dade counties.

R32: Applying civic innovation methods to advance safety education: A pilot program

Principal Investigator – Eric Dumbaugh, Florida Atlantic University
This project details an effort to link creative placemaking techniques with traffic safety through events centered on the Little Havana neighborhood, a lower-income, predominantly immigrant community in Miami.

R33: US Regional Vision Zero Implementation

Principal Investigator – Kelly Evenson, University of North Carolina, Chapel Hill
This project aimed to assess how Vision Zero (VZ) is being implemented nationwide at a regional level, with or without a plan, and identify strengths and weaknesses of differing approaches to safety programming. We also need a better understanding of how best to support communities in their Vision Zero efforts. Using a mixed-method design, we describe municipal-level U.S. Vision Zero initiatives using quantitative data and provide insight from both municipal- and MPO-level initiatives using in-depth interviews.

R34: COVID-19 streets: Mobility justice and the rapid rollout of pedestrian and bicyclist improvements

Principal Investigator – Tab Combs, University of North Carolina, Chapel Hill
This study analyzed the impacts of rapid-rollout shared streets programs implemented in response to changes in travel demand brought on by the COVID-19 pandemic. Shared streets are those that have been converted to pedestrian- and bicycle-priority zones using temporary materials, typically involving some sort of traffic calming or diversion. The research sought to understand the impacts of these shared streets on pedestrians and cyclists, with respect to safety, equity, and mobility by (1) comparing pedestrian and bicycle traffic volumes in nine treatment cities—cities that implemented robust shared streets programs during and because of the pandemic—and seven peer control cities, and (2) exploring the motivations, planning processes, and outcomes of shared streets in the treatment cities.

R35: Using Safe Systems approach to assess traffic impact and land development

Principal Investigator – Tab Combs, University of North Carolina, Chapel Hill
There is a paucity of research into the relationship between land development and road safety outcomes. Through qualitative analysis of interviews and focus groups with traffic impact analysis practitioners, we uncover and unpack self-defeating narratives about the complex relationship between safety and congestion.

R37: Applying AcciMap to e-Scooter Crashes: A Safe Systems approach to analyzing micromobility

Principal Investigator – Katherine Harmon, University of North Carolina, Chapel Hill
With an urgent need to reduce micromobility injuries, combined with a recognition of the broader dynamic transportation system and environment at play, we sought to examine the applicability of the AcciMap systems mapping tool to help disentangle potential injury influencers and relatedly, pinpoint strategic intervention opportunities for e-scooter injury prevention in a U.S. context.

R38: Assessing how private beliefs conflict with public action on Safe Systems

Principal Investigator – Seth LaJeunesse, University of North Carolina, Chapel Hill
The research team surveyed 1,000 residents of North Carolina about their transportation values, travel mode aspirations, perceptions of others’ values and aspirations, travel habits, transportation-related political activity, and demographic factors. Participants were not always accurate with their assessment of others’ values and travel mode aspirations, and this
pluralistic ignorance around others’ values and aspirations varied. The report ends with conclusions and practical implications toward addressing pluralistic ignorance about what others most want and need from their transportation system and aligning transportation investments with communities’ expressed values and aspirations.

R39: Integrating systems thinking tools into Vision Zero and Safe Systems approaches

Principal Investigator – Becky Naumann, University of North Carolina, Chapel Hill
In this project, we tailored and supported use of five systems thinking tools (the 5 Rs Framework, Goal and Action Alignment Mapping, System Support Mapping, Balance of Petals Diagramming, and Causal Loop Diagramming) across a variety of transportation-related coalitions and partnerships to help them meet systems-based strategic planning and collaboration goals. We provide descriptions, case studies, how-to guides, and evaluation feedback on all five tools.

R40: A Safe Systems approach to motorcycle safety

Principal Investigator – Eric Dumbaugh, University of North Carolina, Chapel Hill
This study examines motorcycle safety from a Safe Systems perspective. The report is divided into two sections. The first section is a synthetic review of the literature that seeks to understand motorcycle safety from within the four dimensions that comprise a Safe System. The second section examines motorcycle crash data to uncover patterns in those involved in the crashes, locations, and times of the crashes.

R42: Advancing crash investigation with connected and automated vehicle data – Phase 2

Principal Investigator – Asad Khattak, University of Tennessee, Knoxville
This report explores the advancement of crash investigation through connected and automated vehicle data by answering several research questions: (1) What insights can be gained from automated vehicle (AV) crashes? (2) What are the gaps in AV safety performance? (3) Which crash contributors are revealed by AV sensors? (4) What pertinent information is missing in crash investigations? (5) What is the preparedness of law enforcement to use AV data? And (6) What insights are gained from on-road AV crash narratives? The results revealed that AV sensors provide valuable information about vehicle trajectories, which is usually unavailable. The above questions (2 and 6) are addressed by combining text analytics of crash narratives and Bayesian methods to assess how pre-crash conditions, automated driving mode, and crash types are associated with crash severity. This method revealed that AVs operating on ramps or slip lanes often experience higher injury severity. Questions 4 and 5 are addressed by surveying crash investigators in law enforcement and assessing their familiarity and experience with AV data.

R43: Applying AI to data sources to improve driver-pedestrian interactions at intersections

Principal Investigator – Subhadeep Chakraborty, University of Tennessee, Knoxville
This report incorporates pedestrian safety into the optimization of traffic signals by collecting and linking data from traffic signals (cameras) and analyzing the behaviors of pedestrians and drivers at intersections using Artificial Intelligence techniques. It explores rare pedestrian crashes at intersections, called “corner cases,” using Fatality Analysis Reporting System (FARS) data and applying text analytics and the K-means unsupervised learning approach. It continues by investigating the determinants of nighttime pedestrian crash injury severity in pedestrian-involved crashes on intersections using the Random Forest algorithm and ordered logit models. The analysis results reveal that alcohol impairment, foggy weather, elderly pedestrians, a speed limit of 50-55 mph, and motorists not yielding to pedestrians are more likely to contribute to severe pedestrian injuries at intersections.

R44: Safety enhancement by detecting driver impairment through analysis of real-time volatilities

Principal Investigator – Asad Khattak, University of Tennessee, Knoxville
This project developed a framework to detect driver impairment using extensive real-time driver biometric information along with data related to vehicle kinematics and the roadway environment. The project’s primary objective was to advance safety measures by closely monitoring driver behavior, examining changes in driver biometric characteristics under different distracted driving scenarios, and promptly identifying signs of driver impairment. The project’s ultimate goal is to integrate early indicators of driving impairment into advanced driver assistance systems (ADAS) to provide feedback and warnings to the driver and surrounding vehicles, potentially helping to prevent accidents and improve overall safety on the road. This development holds significant promise for improving traffic safety, given the substantial interest of major automotive and information technology stakeholders in these applications, particularly those involved in fleet vehicles.

RR1: Explaining the rise in pedestrian fatalities: A Safe Systems approach

Principal Investigator – Laura Sandt, University of North Carolina, Chapel Hill
Pedestrian fatalities increased to 5,987 in 2016, compared to 5,495 (2015) and 4,910 (2014), or an increase of 22% in the past 2 years. This project demonstrated an application of innovative systems science tools as a means for examining underlying drivers of complex problems. An initial set of systems mapping workshops with diverse stakeholders produced numerous theories involving about 40 key variables and themes related to the rise of pedestrian fatalities, many of which were further substantiated by additional data and literature scans. Additionally, hypotheses about system structures—including balancing and reinforcing feedback loops—thought to be accelerating or mitigating the fatality trends were uncovered.

RR2: US Vision Zero Implementation

Principal Investigator – Kelly Evenson, University of North Carolina, Chapel Hill
This project builds upon projects “R1: Structures of Stakeholder Relationships in Making Road Safety Decisions” and “R17: Strengthening Existing and Facilitating New Vision Zero Plans.” Our team documented the early awareness and involvement of road safety professionals in Vision Zero. The project’s final report is co-written with project R33: US Regional Vision Zero Implementation.

Discontinued Projects

R36: Laying the Groundwork for a National Pedestrian Injury Surveillance System

Principal Investigator – Katherine Harmon, University of North Carolina, Chapel Hill
This project was discontinued because of changes to external circumstances.

R41: Bike-sharing as a safety intervention: Evidence from nine large US cities

Principal Investigator – Eric Dumbaugh, University of North Carolina, Chapel Hill
This project was unable to proceed because of unforeseen external circumstances, and no funds were expended on the effort. However, a graphic created in preparation for this project is posted on the page.

For more information, please contact Laura Sandt, CSCRS Director.

These CSCRS research projects, and other U.S. Department of Transportation University Transportation Center (UTC) sponsored projects, are also listed in the Transportation Research Board’s Research in Progress (RiP) Database, as well as Dataverse.

Also, this interactive map shows all the current UTCs by location; by hovering your mouse over a circle, you can see how many projects the UTC has entered in the RiP Database.