CMF / CRF Details

CMF ID: 2917


Star Quality Rating:	[View score details]
Rating Points Total:	80

Crash Modification Factor (CMF)
Value:	0.849
Adjusted Standard Error:
Unadjusted Standard Error:	0.118

Crash Reduction Factor (CRF)
Value:	15 (This value indicates a decrease* in crashes)*
Adjusted Standard Error:
Unadjusted Standard Error:	11.8

Applicability
Crash Type:	All
Crash Severity:	K (fatal),A (serious injury),B (minor injury),C (possible injury)
Roadway Types:	Not Specified
Street Type:
Minimum Number of Lanes:	4
Maximum Number of Lanes:	6
Number of Lanes Direction:
Number of Lanes Comment:
Crash Weather:	Not specified
Road Division Type:	All
Minimum Speed Limit:	30
Maximum Speed Limit:	40
Speed Unit:	mph
Speed Limit Comment:
Area Type:	Urban and suburban
Traffic Volume:
Average Traffic Volume:
Time of Day:	All
If countermeasure is intersection-based
Intersection Type:	Roadway/roadway (not interchange related)
Intersection Geometry:	3-leg,4-leg
Traffic Control:	Other
Major Road Traffic Volume:
Minor Road Traffic Volume:
Average Major Road Volume :	39700 Annual Average Daily Traffic (AADT)
Average Minor Road Volume :	711 Annual Average Daily Traffic (AADT)

Development Details
Date Range of Data Used:	2002 to 2008
Municipality:	Tucson
State:	AZ
Country:
Type of Methodology Used:	Before/after using empirical Bayes or full Bayes

Other Details
Included in Highway Safety Manual?	No
Date Added to Clearinghouse:	Mar-21-2011
Comments:	The authors of this study also experimented with producing additional CMFs from an alternate dataset of crashes (based on a different definition of relation to intersection). Since this did not add new knowledge to this topic, these CMFs were not included in the Clearinghouse. The CMFs reported in the Clearinghouse reflect the final CMFs noted in the report summary and abstract. The number of crashes in the after period were not reported in this study, however, they have been recorded as 300 to give 10 points as a beneift of doubt for one or more of the following: (1) number of miles/sites in the reference/treatment group, (2) number of crashes in the references/treatment group, (3) reporting AADTs for the aggregate dataset but not for the disaggragate dataset used for CMF development.