Study Details

Study Title: Impact of adaptive traffic control systems on crash frequency and severity

Authors: Fink et al.

Publication Date: JAN, 2015

Abstract: Despite seeing widespread usage worldwide, adaptive traffic control systems have experienced relatively little use in the United States. Of the systems used, the Sydney Coordinated Adaptive Traffic System (SCATS) is the most popular in America. Safety benefits of these systems are not as well understood nor as commonly documented. This study investigates the safety benefits of adaptive traffic control systems by using the large SCATS-based system in Oakland County, MI known as FAST-TRAC. This study uses data from FAST-TRAC-controlled intersections in Oakland County and compares a wide variety of geometric, traffic, and crash characteristics to similar intersections in metropolitan areas elsewhere in Michigan. Data from 498 signalized intersections are used to conduct a cross-sectional analysis. Negative binomial models are used to estimate models for three dependent crash variables. Multinomial logit models are used to estimate an injury severity model. A variable tracking the presence of FAST-TRAC controllers at intersections is used in all models to determine if a SCATS-based system has an impact on crash occurrences or crash severity. It is found to be statistically significant in 8 models. Estimates show angle crashes could be reduced by up to 19.3% at intersections with SCATS-based controllers. Severity results show a statistically significant increase in non-serious injuries, but not a significant reduction in incapacitating injuries or fatal accidents.

Study Citation: Fink, J., V. Kwigizile, and J. Oh. "Impact of adaptive traffic control systems on crash frequency and severity". Presented at the 94th Annual Meeting of the Transportation Research Board, Paper No. 15-3076, Washington, D.C., (2015).

Related Citations: Fink, J., V. Kwigizile, and J. Oh. "Quantifying the impact of adaptive traffic control systems on crash frequency and severity: Evidence from Oakland County, Michigan". Journal of Safety Research, Vol. 57, (2016) pp. 1-7

CMFs Associated With This Study

Category: Intersection traffic control

Countermeasure: Install adaptive traffic signal control

CMF CRF(%) Quality Crash Type Crash Severity Roadway Type Area Type
0.807 19.3 3 Stars Angle All Not specified Urban and suburban