CMF / CRF Details

CMF ID: 9887

Convert signalized intersection to multi-lane roundabout


Prior Condition: Four Leg Signalized Intersection

Category: Intersection geometry

Study: Whether Conversion and Weather Matter to Roundabout Safety, , 2018

Star Quality Rating: 4 Stars   [View score details]
Rating Points Total: 130
Crash Modification Factor (CMF)
Value: 3.333
Adjusted Standard Error:
Unadjusted Standard Error: 0.004
Crash Reduction Factor (CRF)
Value: -233.3   (This value indicates an increase in crashes)
Adjusted Standard Error:
Unadjusted Standard Error: 0.4
Crash Type: All
Crash Severity: O (property damage only)
Roadway Types: All
Street Type:
Minimum Number of Lanes: 4
Maximum Number of Lanes: 4
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: Roadway/roadway (not interchange related)
Intersection Geometry: 4-leg
Traffic Control: Roundabout
Major Road Traffic Volume:
Minor Road Traffic Volume:
Average Major Road Volume :
Average Minor Road Volume :
Development Details
Date Range of Data Used: 2006 to 2016
Municipality: Region of Waterloo
Country: Canada
Type of Methodology Used: Before/after using empirical Bayes or full Bayes
Sample Size (crashes): 103 crashes before, 452 crashes after
Sample Size (sites): 5 sites before, 5 sites after
Sample Size (site-years): 135 site-years before, 101 site-years after
Other Details
Included in Highway Safety Manual? No
Date Added to Clearinghouse: Mar-11-2019