CMF / CRF Details

CMF ID: 4189

Convert signalized intersection to modern roundabout

Description:

Prior Condition: Signalized intersection

Category: Intersection geometry

Study: Safety Effectiveness of Converting Signalized Intersections to Roundabouts, Gross et al., 2012

 
Star Quality Rating: 4 Stars   [View score details]
Crash Modification Factor (CMF)
Value: 0.45
Adjusted Standard Error:
Unadjusted Standard Error: 0.1
Crash Reduction Factor (CRF)
Value: 55   (This value indicates a decrease in crashes)
Adjusted Standard Error:
Unadjusted Standard Error: 10
Applicability
Crash Type: All
Crash Severity: A (serious injury),B (minor injury),C (possible injury)
Roadway Types: Not Specified
Number of Lanes: 1 to 2
Road Division Type:
Speed Limit: 15-35 mph
Area Type: Urban
Traffic Volume:
Average Traffic Volume:
Time of Day: All
If countermeasure is intersection-based
Intersection Type: Roadway/roadway (not interchange related)
Intersection Geometry: 3-leg,4-leg
Traffic Control: Roundabout
Major Road Traffic Volume: Minimum of 5300 to Maximum of 52500 Average Daily Traffic (ADT)
Minor Road Traffic Volume:
Average Major Road Volume :
Average Minor Road Volume :
Development Details
Date Range of Data Used: 2000 to 2009
Municipality:
State: CO, FL, IN, MD, MI, NY, NC, SC, VT, WA
Country:
Type of Methodology Used: Before/after using empirical Bayes or full Bayes
Sample Size (sites): 13 sites after
Other Details
Included in Highway Safety Manual? No
Date Added to Clearinghouse: Nov-01-2012
Comments: Countermeasure name has been slightly modified for consistency across Clearinghouse