CMF / CRF Details
CMF ID: 10237
Change from horizontal tangent to a flat horizontal curve
Description: Change horizontal tangent to a curve with a radius between 8,000 ft and 20,000 ft
Prior Condition: Horizontal tangent
Category: Alignment
Study: Development of crash modification factors of horizontal curve design features for single-motorcycle crashes on rural two-lane highways: A matched case-control study, Xin et al., 2019
| Star Quality Rating: |  [View score details] |
| Rating Points Total: | 115 |
| Crash Modification Factor (CMF) | |
|---|---|
| Value: | 1.62 |
| Adjusted Standard Error: | |
| Unadjusted Standard Error: | 0.35 |
| Crash Reduction Factor (CRF) | |
|---|---|
| Value: | -62 (This value indicates an increase in crashes) |
| Adjusted Standard Error: | |
| Unadjusted Standard Error: | 35 |
| Applicability | |
|---|---|
| Crash Type: | Other |
| Crash Severity: | All |
| 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: | 15 |
| Maximum Speed Limit: | 70 |
| Speed Unit: | mph |
| Speed Limit Comment: | |
| Area Type: | Rural |
| Traffic Volume: | Minimum of 10 to Maximum of 57000 Annual Average Daily Traffic (AADT) |
| Average Traffic Volume: | 3600 Annual Average Daily Traffic (AADT) |
| 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: | 2005 to 2015 |
| Municipality: | |
| State: | FL |
| Country: | USA |
| Type of Methodology Used: | Case-control |
| Sample Size (crashes): | 1704 crashes |
| Sample Size (miles): | 929 miles |
| Sample Size (mile-years): | 10219 mile-years |
