CMF / CRF Details

CMF ID: 9789

Conversion of intersection into multi-lane roundabout

Description: Conversion of intersection into multi-lane roundabout.

Prior Condition: Traffic circle

Category: Intersection geometry

Study: Crash Modification Factors Based on Crash Histories of 148 Modern Roundabouts in Five States, Zhang and Wang, 2017

 
Star Quality Rating: 3 Stars   [View score details]
Crash Modification Factor (CMF)
Value: 3.06
Adjusted Standard Error:
Unadjusted Standard Error: 0.79
Crash Reduction Factor (CRF)
Value: -206   (This value indicates an increase in crashes)
Adjusted Standard Error:
Unadjusted Standard Error: 79
Applicability
Crash Type: All
Crash Severity: All
Roadway Types: Not specified
Number of Lanes:
Road Division Type:
Speed Limit:
Area Type: Not specified
Traffic Volume:
Average Traffic Volume:
Time of Day: Not specified
If countermeasure is intersection-based
Intersection Type: Roadway/roadway (not interchange related)
Intersection Geometry: Not specified
Traffic Control: Stop-controlled
Major Road Traffic Volume:
Minor Road Traffic Volume:
Average Major Road Volume :
Average Minor Road Volume :
Development Details
Date Range of Data Used: 2005 to 2013
Municipality:
State: FL, IN, NY, PA, WA
Country: USA
Type of Methodology Used: Simple before/after
Sample Size (crashes): 60 crashes before, 245 crashes after
Sample Size (sites): 1 sites before, 1 sites after
Other Details
Included in Highway Safety Manual? No
Date Added to Clearinghouse: Oct-27-2018
Comments: Traffic circle to multi-lane roundabout