CMF / CRF Details

CMF ID: 217

Convert signalized intersection to modern roundabout

Description:

Prior Condition:  No Prior Condition(s)

Category: Intersection geometry

Study: Safety Effects of Roundabouts in Flanders: Signal Type, Speed Limits, and Vulnerable Road Users, De Brabander and Vereeck, 2007

 
Star Quality Rating:2 Stars  [View score details]
Rating Points Total:40
Crash Modification Factor (CMF)
Value:0.87
Adjusted Standard Error:
Unadjusted Standard Error:0.18
Crash Reduction Factor (CRF)
Value:13  (This value indicates a decrease in crashes)
Adjusted Standard Error:
Unadjusted Standard Error:18
Applicability
Crash Type:All
Crash Severity:A (serious injury)
Roadway Types:Not specified
Street Type:
Minimum Number of Lanes:
Maximum Number of Lanes:
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:Not specified
Traffic Volume:
Average Traffic Volume:
Time of Day:
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:
Municipality:
State:
Country:
Type of Methodology Used:Before/after using empirical Bayes or full Bayes
Other Details
Included in Highway Safety Manual?No
Date Added to Clearinghouse:Dec 01, 2009
Comments:Countermeasure name has been slightly modified for consistency across Clearinghouse The number of crashes in the after period were not reported in this study, however, they have been recorded as 300 to give 10 points as a beneift of doubt for one or more of the following: (1) number of miles/sites in the reference/treatment group, (2) number of crashes in the references/treatment group, (3) reporting AADTs for the aggregate dataset but not for the disaggragate dataset used for CMF development.