CMF / CRF Details

CMF ID: 9897

Change permissive left-turn phasing to protected only or protected/permissive

Description: Treatment group includes intersections where signal phases were changed from permissive to protected-only or protected/permissive.

Prior Condition: Intersections with permissive left-turn signal phasing.

Category: Intersection traffic control

Study: Safety Evaluation of Protected Left-Turn Phasing and Leading Pedestrian Intervals on Pedestrian Safety, Goughnour et al., 2018

 
Star Quality Rating: 4 Stars   [View score details]
Crash Modification Factor (CMF)
Value: 1.091
Adjusted Standard Error:
Unadjusted Standard Error: 0.066
Crash Reduction Factor (CRF)
Value: -9.1   (This value indicates an increase in crashes)
Adjusted Standard Error:
Unadjusted Standard Error: 6.6
Applicability
Crash Type: Vehicle/pedestrian
Crash Severity: All
Roadway Types: All
Number of Lanes:
Road Division Type:
Speed Limit:
Area Type:
Traffic Volume:
Average Traffic Volume:
Time of Day: All
If countermeasure is intersection-based
Intersection Type: Roadway/roadway (not interchange related)
Intersection Geometry: Not specified
Traffic Control: Signalized
Major Road Traffic Volume:
Minor Road Traffic Volume:
Average Major Road Volume :
Average Minor Road Volume :
Development Details
Date Range of Data Used: 2001 to 2014
Municipality: Chicago, New York City, Toronto
State: notusa, IL, NY
Country: USA, Canada
Type of Methodology Used: Before/after using empirical Bayes or full Bayes
Sample Size (crashes): 651 crashes before, 432 crashes after
Sample Size (sites): 148 sites before, 148 sites after
Other Details
Included in Highway Safety Manual? No
Date Added to Clearinghouse: Mar-11-2019
Comments: Crash Type = Vehicle-Pedestrian Crashes