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Published on: February 1, 2020
The influence of rear turn-signal characteristics on crash risk
John M Sullivan1, Michael J Flannagan
1University of Michigan Transportation Research Institute, 2901 Baxter Rd., Ann Arbor, MI 48109–2150, USA. jsully@umich.edu
Introduction:
The relationship between the relative risk of a rear-end collision during a turn, merge, or lane change maneuver and the characteristics of the rear turn-signal configuration was examined using crash data from seven states in the United States.
Method:
Rear turn-signal characteristics-including color, optics, separation, and light source-were identified for 55 vehicle models and used in a logistic regression analysis to model the odds of a rear-end collision. Additional variables including driver demographics (gender, age), vehicle age, and light condition were also modeled. Risk was assessed using a contrast group of striking vehicles in similar collisions.
Results:
The results suggest that the odds of being the struck vehicle were 3% to 28% lower among vehicles equipped with amber versus red turn signals. Although the analysis suggests that there may be a safety benefit associated with amber rear turn signals, it is unclear whether turn-signal color alone is responsible.
Impact On Industry:
The results suggest that aspects of a vehicle's rear signal characteristics may influence crash risk.
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