CMF / CRF Details
CMF ID: 9899
Change permissive left-turn phasing to protected only or protected/permissive
Description: Treatment group includes intersections where signal phases were changed from permissive to protected-only or protected/permissive.
Prior Condition: Intersections with permissive left-turn signal phasing.
Category: Intersection traffic control
Study: Safety Evaluation of Protected Left-Turn Phasing and Leading Pedestrian Intervals on Pedestrian Safety, Goughnour et al., 2018
| Star Quality Rating: |  [View score details] |
| Rating Points Total: | 150 |
| Crash Modification Factor (CMF) | |
|---|---|
| Value: | 0.942 |
| Adjusted Standard Error: | |
| Unadjusted Standard Error: | 0.028 |
| Crash Reduction Factor (CRF) | |
|---|---|
| Value: | 5.8 (This value indicates a decrease in crashes) |
| Adjusted Standard Error: | |
| Unadjusted Standard Error: | 2.8 |
| Applicability | |
|---|---|
| Crash Type: | Other |
| Crash Severity: | K (fatal),A (serious injury),B (minor injury),C (possible injury) |
| Roadway Types: | All |
| 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: | |
| Minimum Speed Limit: | |
| Maximum Speed Limit: | |
| Speed Unit: | |
| Speed Limit Comment: | |
| Area Type: | |
| Traffic Volume: | |
| Average Traffic Volume: | |
| Time of Day: | All |
| If countermeasure is intersection-based | |
| Intersection Type: | Roadway/roadway (not interchange related) |
| Intersection Geometry: | Not specified |
| Traffic Control: | Signalized |
| Major Road Traffic Volume: | |
| Minor Road Traffic Volume: | |
| Average Major Road Volume : | |
| Average Minor Road Volume : | |
| Development Details | |
|---|---|
| Date Range of Data Used: | 2001 to 2014 |
| Municipality: | Chicago, New York City, Toronto |
| State: | notusa,IL,NY |
| Country: | USA, Canada |
| Type of Methodology Used: | Before/after using empirical Bayes or full Bayes |
| Sample Size (crashes): | 3993 crashes before, 2410 crashes after |
| Sample Size (sites): | 148 sites before, 148 sites after |
| Other Details | |
|---|---|
| Included in Highway Safety Manual? | No |
| Date Added to Clearinghouse: | Mar 11, 2019 |
| Comments: | Crash Type = Vehicle-Vehicle Crashes |
