TSCNewsletter:GSR Seminars

TSC Graduate Researchers Reach Across Disciplines

A Summer Seminar Series Stimulates
Cross-Departmental Thinking

Understanding what makes neighborhoods safe for walking, developing systems to make turns safer at intersections, uncovering the latest research on the traffic dangers of country roads, seeing California 's traffic injuries in the context of disease burden—these are among topics explored this summer by Graduate Student Researchers at UC Berkeley's Traffic Safety Center.

The students came from a variety of backgrounds including public health, urban planning, and civil and environmental engineering. Their projects culminated in a series of weekly seminars that gave students a chance to present their work to people from other disciplines and hear reactions from the center's staff and students.

The following are highlights from some of the presentations.

Carol Kolb, a master's student in the Environmental Health Sciences, started the series July 16 with a presentation on disability-adjusted life years, or DALYs. Traffic risks are normally calculated in terms of fatality or injury, but the DALY method, Kolb explained, is a way of measuring how many years of a person's life are "lost" to disease or injury. DALYs give a picture of how the traffic-related disease burden impacts a population by measuring how much healthy time a person loses to disease. They are calculated by adding years of lost life (YLLs)—the difference between a person's age at death and his or her life expectancy at the age of death—and, in the case of those who survive their injuries, years lost to disability (YLDs), a figure that is derived by assessing both the severity and duration of a disability.

This method is used by the World Health Organization to measure the global burden of disease. Road traffic crashes are a leading contributor to the global disease burden—they are currently ranked ninth, but by 2020 are expected to climb to third, behind heart attacks and unipolar major depression. DALYs, Kolb said, were the first attempt at a comprehensive picture of global health. By using DALYs to measure California 's traffic-related disease burden, researchers would be able to compare regional DALY rates and also see how California fits into the global disease burden picture.

The Los Angeles and San Francisco Departments of Public Health have both conducted burden-of-disease analyses using DALYs, Kolb said. While the traffic-related burden was a component of these analyses, it was not a focus.

"My research is unique in the sense that it looks at traffic-related burden specifically, as opposed to all diseases, and breaks it down into pedestrian, occupant, motorcyclist, and bicyclist categories," she said. "By doing this we are able to have a much more detailed—and therefore, more useful—picture of the distribution of traffic-related burden between occupant crashes, pedestrian crashes, etc. I also looked at ethnicities, which many burden studies don't do."

Two GSR participants, Melissa Kealey and Christina Ferracane, focused on built environment and physical activity in their presentations.

"I come from a transportation engineering background, so I mesh urban design with transportation," said Ferracane, a master's student in City and Regional Planning. "My particular interest is in pedestrians. Research on the built environment and physical activity—walking—turned out to be the perfect combination for my interests."

In her presentation, Ferracane summarized the findings of a study she and TSC faculty, staff and consultants worked on over the summer in preparation for a proposal to study the relationship between the built environment and walking behavior of residents in neighborhoods in a number of cities along the San Pablo Ave. corridor in the East Bay. TSC researchers studied walking behaviors of individuals in the corridor. "There is a lot of literature in the transportation field on walking and a lot of information on physical activity in the public health field," Ferracane said. The purpose of the TSC study, she explained, was to see how they could synthesize information from both perspectives.

Aleksandr Zabyshny, a graduate student in civil and environmental engineering, presented his work on intersection decision support (IDS). Zabyshny is researching the development of an IDS system intended to reduce the number of crossing-path crashes at intersections. This specific system would consist of sensors and signals at intersections where left turns are permissible on a green light across oncoming traffic. Sensors would measure the speed and closeness of oncoming vehicles and calculate whether there was room and time for a left turn. A signal activated by the sensors would tell the driver whether it was safe to make the maneuver.

A version of the system was demonstrated in the Washington D.C. area earlier this summer. This fall, the center will begin researching the feasibility of placing an IDS system at an intersection in the Bay Area. Zabyshny and TSC Director David Ragland will begin the project by gathering data on traffic patterns at the intersection of Hearst and Shattuck Aves., where there is no left turn signal and a significant amount of cross-traffic makes left turns.

"I have been interested in research associated with improvement of transportation safety," Zabyshny said. "Working on this project is a great opportunity to extend my knowledge as well as to contribute to the actual development of countermeasures that are expected to result in transportation safety improvement."

The seminars demonstrated the interconnectedness of public health, urban planning, and engineering, and also showed how drawing on knowledge from these diverse fields could speed solutions to traffic safety problems.

"The participants presented their work in an open, multi-disciplinary context," Ragland said. "We believe the students and staff were really able to learn from one another."

Additional students participating in the series included Lesliam Quiros, an environmental health sciences graduate student who presented a survey of research being done around the country on rural traffic injuries, and Melissa Kealey, a graduate student in epidemiology studying built environment and physical activity.