Training and education

Pre-hospital Care of Road Traffic Injuries in Chiang Mai, Thailand

Brown, Ted R.
Geyer, Judy A.
Taghavy, Azita
Mitchell, Brian P.
Ragland, David R.
2004

In many developing countries, transportation infrastructure development lags behind the tremendous growth in motorization. Road traffic injuries cause enormous morbidity and mortality worldwide, placing heavy burdens on global and national economies. Underdeveloped transportation infrastructures critical to traffic safety include roadway improvement, occupant protection laws, traffic law enforcement, and emergency medical services (EMS). Highlighting one important aspect of lagging infrastructure, this article focuses on emergency medical services. This research study offers a descriptive...

Impact of Pedestrian Presence on Movement of Left-Turning Vehicles: Method, Preliminary Results & Possible Use in Intersection Decision Support

Banerjee, Ipsita
Shladover, Steven E.
Misener, James A.
Chan, Ching-Yao
Ragland, David R.
2004

Warning systems are being developed for left-turning vehicles at intersections where protected left-turns are not warranted or cannot be provided, based on limitations of right of way or intersection capacity. These are meant to provide warnings to left-turning vehicles of vehicles approaching from the opposite direction, when the time to turn may be deemed unsafe. To implement these warning systems, it is necessary to estimate in near real time, the probability of conflict between the two approaching vehicles. A study is being conducted with the help of video and radar at various...

Pedestrian Volume Modeling for Traffic Safety and Exposure Analysis: The Case of Boston, Massachusetts

Raford, Noah
Ragland, David R.
2005

This paper examines three types of pedestrian volume models in light of their usefulness for estimating pedestrian exposure for pedestrian safety research. The need for pedestrian flow data as part of pedestrian exposure and safety analysis is outlined, and the background of each type of model is discussed. It then selects the space syntax network analysis model to estimate pedestrian volumes for the city of Boston, Massachusetts. It was found that the model was able to accurately predict pedestrian flows (r-squared 0.81, p-value < 0.0001) after incorporating distance to transit stops...

Providing Intersection Decision Support under Challenging Conditions

Shladover, Steven E.
VanderWerf, Joel
Ragland, David R.
2005

This paper describes the results of simulation studies to determine how effectively left-turning drivers can be alerted to imminent conflicts with opposing traffic under difficult operating conditions and with limited detector capabilities. These conditions include approaching vehicles changing speed in locations that are not covered by detectors and detectors that may only be able to detect vehicle presence, but not speed. In cases without direct speed detection, one may try to rely on historical speed statistics to estimate the speed of approaching traffic, but unless the approach speeds...

Gap acceptance for vehicles turning left across on-coming traffic: Implications for Intersection Decision Support design

Ragland, David R.
Arroyo, Sofia
Shladover, Steven E.
Misener, James A.
Chan, Ching-Yao
2005

A left-turning vehicle (Subject Vehicle, SV) attempting to cross the path of an oncoming vehicle (Principal Other Vehicle, POV) at an intersection typically does not have the right of way. The main task of the SV driver is to find an adequate opportunity in opposing traffic to initiate the left-turn maneuver. To reduce the probability of a conflict, warning systems, such as Intersection Decision Support (IDS) systems, are being developed. These systems alert drivers of SV vehicles attempting to negotiate a left turnabout traffic approaching from the opposite direction. The current...

The Continuing Debate about Safety in Numbers—Data from Oakland, CA

Geyer, Judy A.
Raford, Noah
Ragland, David R.
Pham, Trinh
2006

The primary objective of this paper is to review the appropriate use of ratio variables in the study of pedestrian injury exposure. We provide a discussion that rejects the assumption that the relationship between a random variable (e.g., a population X) and a ratio (e.g., injury or disease per population Y/X) is necessarily negative. In the study of pedestrian risk, the null hypothesis is that pedestrian injury risk is constant with respect to pedestrian volume. This study employs a unique data set containing the number of pedestrian collisions, average annual pedestrian volume, average...

Teens and Driving in California: Summary of Research and Best Practices

Bui, Huong
Arnold, Lindsay S.
Cooper, Jill F.
Ragland, David R.
2006

The purpose of this guide is to present the major risk factors associated with teen driving in California and to highlight policy and program strategies that may be influential in reducing risk.

Estimating Pedestrian Accident Exposure: Protocol Report

Greene-Roesel, Ryan
Diogenes, Mara Chagas
Ragland, David R.
2007

Walking is a healthful, environmentally benign form of travel, and is the most basic form of human mobility. Walking trips account for more than 8 percent of all trips taken in California, making walking the second most commonly used mode of travel after the personal automobile (Caltrans, 2002). In addition, many trips made by vehicle or public transit begin and end with walking.

In spite of the importance and benefits of walking, pedestrians suffer a disproportionate share of the harm of traffic incidents in California. As noted above...

Evaluation of the California Child Passenger Safety Initiative

Cooper, Jill F.
MacLeod, Kara E.
Ragland, David R.
2004

Motor vehicle injuries are a leading cause of injury and fatality to children. Child restraint systems can reduce injury, and their use has been a long-time focus of policy and programmatic work. During this time, there has been a marked increase in the number of children restrained in vehicles and a steady decline in vehicle-related injuries and fatalities to children. However, data reveal that children of color, compared to white children, are at greater risk of injury in motor vehicle crashes. To address needs of “the children left behind” from safety advances, the California Child...

Vehicle Occupancy and Crash Risk

Geyer, Judy A.
Ragland, David R.
2004

This study explores the association between vehicle occupancy and a driver’s risk of causing a fatal crash, not wearing a seatbelt, and using alcohol. The survey population is the set of drivers represented in the Fatal Analysis Reporting System (FARS) (years 1992 to 2002). The independent variables are driver age, driver gender, passenger age, passenger gender, and vehicle occupancy. The outcome variables are whether the driver was at fault in causing the fatal crash, whether the driver wore a seatbelt, and whether the driver had been using alcohol. For male teenager drivers, driving with...