CMF / CRF Details

CMF ID: 9392

Install cable median barrier

Description: Install cable median barrier

Prior Condition: Roadways without median cable barriers

Category: Roadside

Study: Crash Modification Factors for Median Cable Barriers in Tennessee, Bryant, 2018

Star Quality Rating: 2 Stars   [View score details]
Crash Modification Factor (CMF)
Value: 1.18
Adjusted Standard Error:
Unadjusted Standard Error:
Crash Reduction Factor (CRF)
Value: -18   (This value indicates an increase in crashes)
Adjusted Standard Error:
Unadjusted Standard Error:
Crash Type: All
Crash Severity: O (property damage only)
Roadway Types: Not specified
Number of Lanes:
Road Division Type:
Speed Limit:
Area Type:
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
Type of Methodology Used: Before/after using comparison group
Sample Size (sites): 316 sites before, 316 sites after
Sample Size (site-years): 1264 site-years before, 948 site-years after
Other Details
Included in Highway Safety Manual? No
Date Added to Clearinghouse: Oct-27-2018