CMF / CRF Details

CMF ID: 6856

Install adaptive traffic signal control

Description: ATSC is a traffic management strategy in which traffic signal timings change, or adapt, based on observed traffic demand. These systems utilize increased detection to continually collect data on observed demand, and signal timings are then re-optimized based on current data.

Prior Condition:  Intersections with regular traffic signals

Category: Intersection traffic control

Study: Estimation of the Safety Effects of an Adaptive Traffic Signal Control System, Ma et al., 2015

Star Quality Rating:3 Stars  [View score details]
Rating Points Total:95
Crash Modification Factor (CMF)
Adjusted Standard Error:
Unadjusted Standard Error:0.05
Crash Reduction Factor (CRF)
Value:17  (This value indicates a decrease in crashes)
Adjusted Standard Error:
Unadjusted Standard Error:5
Crash Type:All
Crash Severity:All
Roadway Types:All
Street Type:
Minimum Number of Lanes:
Maximum Number of Lanes:
Number of Lanes Direction:
Number of Lanes Comment:
Crash Weather:Not specified
Road Division Type:
Minimum Speed Limit:
Maximum Speed Limit:
Speed Unit:
Speed Limit Comment:
Area Type:Urban and suburban
Traffic Volume:
Average Traffic Volume:
Time of Day:All
If countermeasure is intersection-based
Intersection Type:Not specified
Intersection Geometry:3-leg,4-leg
Traffic Control:Signalized
Major Road Traffic Volume:Minimum of 6667 to Maximum of 49384 Annual Average Daily Traffic (AADT)
Minor Road Traffic Volume:Minimum of 387 to Maximum of 19010 Annual Average Daily Traffic (AADT)
Average Major Road Volume :24470 Annual Average Daily Traffic (AADT)
Average Minor Road Volume :4944 Annual Average Daily Traffic (AADT)
Development Details
Date Range of Data Used:2006 to 2013
Type of Methodology Used:Before/after using empirical Bayes or full Bayes
Sample Size (crashes):1747 crashes before, 393 crashes after
Sample Size (sites):47 sites before, 47 sites after
Sample Size (site-years):235 site-years before, 66 site-years after
Other Details
Included in Highway Safety Manual?No
Date Added to Clearinghouse:Nov 01, 2015