CMF / CRF Details
Change permissive left-turn phasing to protected only or protected/permissive
Countermeasure ID: 9891
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
| Crash Modification Factor (CMF) |
|---|
| Value: | 0.718 |
| Adjusted Standard Error: | |
| Unadjusted Standard Error: | 0.196 |
| Crash Reduction Factor (CRF) |
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| Value: | 28.2 (This value indicates a decrease in crashes) |
| Adjusted Standard Error: | |
| Unadjusted Standard Error: | 19.6 |
| Applicability |
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| Crash Type: | Vehicle/pedestrian |
| Crash Severity: | All |
| 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: | Minimum of 19114 to Maximum of 36289 Annual Average Daily Traffic (AADT) |
| Minor Road Traffic Volume: | Minimum of 3887 to Maximum of 26564 Annual Average Daily Traffic (AADT) |
| Average Major Road Volume : | 26288 Annual Average Daily Traffic (AADT) |
| Average Minor Road Volume : | 14477 Annual Average Daily Traffic (AADT) |
| Development Details |
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| Date Range of Data Used: | 2001 to 2014 |
| Municipality: | New York City |
| State: | NY |
| Country: | |
| Type of Methodology Used: | Before/after using empirical Bayes or full Bayes |
| Sample Size (crashes): | 101 crashes before, 16 crashes after |
| Sample Size (sites): | 7 sites before, 7 sites after |
| Other Details |
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| Included in Highway Safety Manual? | No |
| Date Added to Clearinghouse: | Mar 11, 2019 |
| Comments: | Crash Type = Vehicle-Pedestrian Crashes |
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