CMF / CRF Details
CMF ID: 3173
Installation of cable barriers in freeway medians
Description: Installation of cable barriers in medians of Interstate locations
Prior Condition: No median barrier
Category: Roadside
Study: Hierarchical Bayesian Modeling for Before and After Studies, Olsen et al., 2011
| Star Quality Rating: |  [View score details] |
| Rating Points Total: | 40 |
| Crash Modification Factor (CMF) | |
|---|---|
| Value: | 0.56 |
| Adjusted Standard Error: | |
| Unadjusted Standard Error: | 0.104 |
| Crash Reduction Factor (CRF) | |
|---|---|
| Value: | 44 (This value indicates a decrease in crashes) |
| Adjusted Standard Error: | |
| Unadjusted Standard Error: | 10.4 |
| Applicability | |
|---|---|
| Crash Type: | All |
| Crash Severity: | K (fatal),A (serious injury) |
| Roadway Types: | Principal Arterial Interstate |
| Street Type: | |
| Minimum Number of Lanes: | |
| Maximum Number of Lanes: | |
| Number of Lanes Direction: | |
| Number of Lanes Comment: | |
| Crash Weather: | Not specified |
| Road Division Type: | Divided by Median |
| Minimum Speed Limit: | |
| Maximum Speed Limit: | |
| Speed Unit: | |
| Speed Limit Comment: | |
| 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: | 2002 to 2008 |
| Municipality: | |
| State: | UT |
| Country: | |
| Type of Methodology Used: | Before/after using empirical Bayes or full Bayes |
| Sample Size (site-years): | 27 site-years before, 15 site-years after |
