CMF / CRF Details

CMF ID: 2935

Installation of lane narrowing through rumble strips and painted median at rural stop-controlled approaches

Description: Installation of lane narrowing through rumble strips and painted median at rural stop-controlled approaches

Prior Condition:  Major-road approach at rural intersections with two-lane, two-way roadways with two-way STOP-control

Category: Roadway

Study: Two Low Cost Safety Concepts for Two Way Stop Controlled, Rural Intersections on High Speed Two Lane, Two Way Roadways, Hughes et al., 2010

 
Star Quality Rating:1 Star  [View score details]
Rating Points Total:10
Crash Modification Factor (CMF)
Value:1.54
Adjusted Standard Error:
Unadjusted Standard Error:
Crash Reduction Factor (CRF)
Value:-54  (This value indicates an increase in crashes)
Adjusted Standard Error:
Unadjusted Standard Error:
Applicability
Crash Type:Rear end
Crash Severity:All
Roadway Types:Not Specified
Street Type:
Minimum Number of Lanes:1
Maximum Number of Lanes:1
Number of Lanes Direction:
Number of Lanes Comment:
Crash Weather:Not specified
Road Division Type:Undivided
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:Roadway/roadway (not interchange related)
Intersection Geometry:3-leg,4-leg
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:1999 to 2009
Municipality:
State:FL,KY,MO,PA
Country:
Type of Methodology Used:Simple before/after
Sample Size (site-years):53 site-years before, 11 site-years after
Other Details
Included in Highway Safety Manual?No
Date Added to Clearinghouse:Mar 21, 2011
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.