CMF / CRF Details

CMF ID: 7738

Install shoulder rumble strips


Prior Condition: Roadways without should rumble strips

Category: Shoulder treatments

Study: Validation and Application of Highway Safety Manual (Part D) in Florida, Abdel-Aty et al., 2014

Star Quality Rating: 2 Stars   [View score details]
Crash Modification Factor (CMF)
Value: 0.503
Adjusted Standard Error:
Unadjusted Standard Error: 0.161
Crash Reduction Factor (CRF)
Value: 49.7   (This value indicates a decrease in crashes)
Adjusted Standard Error:
Unadjusted Standard Error: 16.1
Crash Type: Run off road
Crash Severity: All
Roadway Types: Not specified
Number of Lanes: 2
Road Division Type: Undivided
Speed Limit:
Area Type: All
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: 2007 to 2010
State: FL
Country: USA
Type of Methodology Used: Before/after using comparison group
Sample Size (crashes): 25 crashes before, 12 crashes after
Sample Size (sites): 56 sites before, 56 sites after
Sample Size (site-years): 112 site-years before, 112 site-years after
Sample Size (miles): 47.942 miles before, 47.942 miles after
Sample Size (miles): 95.9 mile-years before, 95.9 mile-years after
Other Details
Included in Highway Safety Manual? No
Date Added to Clearinghouse: Mar-08-2016
Comments: This CMF applies to single-vehicle run-off-road crashes