CMF / CRF Details
CMF ID: 9786
Convert 2-lane undivided to 4-lane divided road
Description: The road is rebuilt and expanded from an undivided two-lane road into a divided four-lane road
Prior Condition: Undivided two-lane road
Category: Roadway
Study: An Empirical Bayes before-after evaluation of road safety effects of a new motorway in Norway, Elvik et al., 2017
| Star Quality Rating: |  [View score details] |
| Rating Points Total: | 120 |
| Crash Modification Factor (CMF) | |
|---|---|
| Value: | 0.251 |
| Adjusted Standard Error: | |
| Unadjusted Standard Error: | 0.049 |
| Crash Reduction Factor (CRF) | |
|---|---|
| Value: | 74.9 (This value indicates a decrease in crashes) |
| Adjusted Standard Error: | |
| Unadjusted Standard Error: | 4.9 |
| Applicability | |
|---|---|
| Crash Type: | All |
| Crash Severity: | K (fatal),A (serious injury) |
| Roadway Types: | Not specified |
| Street Type: | |
| Minimum Number of Lanes: | 2 |
| Maximum Number of Lanes: | 2 |
| 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: | All |
| Traffic Volume: | |
| Average Traffic Volume: | |
| Time of Day: | Not specified |
| 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: | 1996 to 2015 |
| Municipality: | |
| State: | notusa |
| Country: | Norway |
| Type of Methodology Used: | Before/after using empirical Bayes or full Bayes |
| Sample Size (crashes): | 71 crashes before, 11 crashes after |
| Sample Size (sites): | 47 sites before, 47 sites after |
| Sample Size (site-years): | 329 site-years before, 329 site-years after |
| Sample Size (miles): | 28 miles before, 28 miles after |
| Sample Size (miles): | 196 mile-years before, 196 mile-years after |
| Other Details | |
|---|---|
| Included in Highway Safety Manual? | No |
| Date Added to Clearinghouse: | Oct 27, 2018 |
| Comments: | CMF for killed and injured road users |
