CMF / CRF Details

CMF ID: 2420

Install centerline and shoulder rumble strips

Description: Milled or rolled rumble strips.

Prior Condition:  No Prior Condition(s)

Category: Roadway

Study: Impact of Rumble Strips on Collision Reduction on BC Highways: A Comprehensive Before and After Safety Study, Sayed et al., 2010

 
Star Quality Rating:4 Stars  [View score details]
Rating Points Total:110
Crash Modification Factor (CMF)
Value:0.82
Adjusted Standard Error:
Unadjusted Standard Error:
Crash Reduction Factor (CRF)
Value:18  (This value indicates a decrease in crashes)
Adjusted Standard Error:
Unadjusted Standard Error:
Applicability
Crash Type:All
Crash Severity:K (fatal),A (serious injury)
Roadway Types:Principal Arterial Other
Street Type:
Minimum Number of Lanes:2
Maximum Number of Lanes:4
Number of Lanes Direction:
Number of Lanes Comment:
Crash Weather:Not specified
Road Division Type:All
Minimum Speed Limit:
Maximum Speed Limit:
Speed Unit:
Speed Limit Comment:
Area Type:Rural
Traffic Volume:
Average Traffic Volume:
Time of Day:All
If countermeasure is intersection-based
Intersection Type:
Intersection Geometry:
Traffic Control:
Major Road Traffic Volume:
Minor Road Traffic Volume:
Average Major Road Volume :
Average Minor Road Volume :
Development Details
Date Range of Data Used:2000 to 2006
Municipality:British Columbia
State:notusa
Country:
Type of Methodology Used:Before/after using empirical Bayes or full Bayes
Sample Size (site-years):141 site-years before, 94 site-years after
Other Details
Included in Highway Safety Manual?No
Date Added to Clearinghouse:Jan 01, 1970
Comments: 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.