CMF / CRF Details

CMF ID: 9131

Install cable median barrier

Description: Install cable median barrier

Prior Condition: No Prior Condition(s)

Category: Roadside

Study: Digesting the safety effectiveness of cable barrier systems by numbers, Chimba et al.,, 2017

Star Quality Rating: 3 Stars   [View score details]
Crash Modification Factor (CMF)
Value: 0.16
Adjusted Standard Error:
Unadjusted Standard Error: 0.011
Crash Reduction Factor (CRF)
Value: 84   (This value indicates a decrease in crashes)
Adjusted Standard Error:
Unadjusted Standard Error: 1.1
Crash Type: Other
Crash Severity:
Roadway Types: All
Number of Lanes:
Road Division Type: Divided by Median
Speed Limit:
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: 2003 to 2013
State: TN
Country: USA
Type of Methodology Used: Before/after using empirical Bayes or full Bayes
Sample Size (crashes): 570 crashes before, 230 crashes after
Sample Size (sites): 577 sites before, 577 sites after
Sample Size (site-years): 1731 site-years before, 1731 site-years after
Sample Size (miles): 302 miles before, 302 miles after
Sample Size (miles): 906 mile-years before, 906 mile-years after
Other Details
Included in Highway Safety Manual? No
Date Added to Clearinghouse: Jan-17-2018
Comments: Median related crashes.