CMF / CRF Details

CMF ID: 5648

Implement automated speed enforcement cameras

Description:

Prior Condition: Segments without automated speed enforcement cameras

Category: Advanced technology and ITS

Study: The impacts of speed cameras on road accidents: An application of propensity score matching methods, Li et al., 2013

 
Star Quality Rating: 4 Stars   [View score details]
Rating Points Total: 110
Crash Modification Factor (CMF)
Value: 0.736
Adjusted Standard Error:
Unadjusted Standard Error:
Crash Reduction Factor (CRF)
Value: 26.4   (This value indicates a decrease in crashes)
Adjusted Standard Error:
Unadjusted Standard Error:
Applicability
Crash Type: All
Crash Severity: B (minor injury)
Roadway Types: Not specified
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: 30
Maximum Speed Limit: 40
Speed Unit: km/h
Speed Limit Comment:
Area Type:
Traffic Volume:
Average Traffic Volume: 19000 Annual Average Daily Traffic (AADT)
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: 1999 to 2007
Municipality: Cheshire, Dorset, Greater Manchester, Lancashire, Leicester, Merseyside, Sussex and West Midlands.
State:
Country: UK
Type of Methodology Used: Other before/after
Sample Size (sites): 771 sites before, 771 sites after
Other Details
Included in Highway Safety Manual? No
Date Added to Clearinghouse: Dec-08-2014
Comments: CMF of personal injury collisions at distance to speed camera up to 500 meters using propensity score matching method 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.