CMF / CRF Details

CMF ID: 8726

Install Box Span Signal

Description:

Prior Condition: Intersections with diagonal span signal configurations

Category: Advanced technology and ITS

Study: Safety Evaluation of Box Span Signal Configuration, Yassin et al., 2017

 
Star Quality Rating: 4 Stars   [View score details]
Crash Modification Factor (CMF)
Value: 1.097
Adjusted Standard Error:
Unadjusted Standard Error: 0.099
Crash Reduction Factor (CRF)
Value: -9.7   (This value indicates an increase in crashes)
Adjusted Standard Error:
Unadjusted Standard Error: 9.9
Applicability
Crash Type: Other
Crash Severity: All
Roadway Types: Not specified
Number of Lanes: 0-4
Road Division Type: All
Speed Limit:
Area Type:
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 3220 to Maximum of 66316 Annual Average Daily Traffic (AADT)
Minor Road Traffic Volume: Minimum of 471 to Maximum of 53080 Annual Average Daily Traffic (AADT)
Average Major Road Volume : 18476 Annual Average Daily Traffic (AADT)
Average Minor Road Volume : 7094 Annual Average Daily Traffic (AADT)
Development Details
Date Range of Data Used: 2006 to 2011
Municipality:
State: MI
Country: USA
Type of Methodology Used: Before/after using empirical Bayes or full Bayes
Sample Size (crashes): 223.7 crashes before, 226.3 crashes after
Sample Size (sites): 117 sites before, 117 sites after
Other Details
Included in Highway Safety Manual? No
Date Added to Clearinghouse: Nov-17-2017
Comments: CMF of intersection crashes for drivers at age of 65 or older