Citation

Lyles RW, Lighthizer DR, Drakopoulos A, Woods S. Transp. Res. Rec. 1986; 1068: 34-41.

Copyright

(Copyright © 1986, Transportation Research Board, National Research Council, National Academy of Sciences USA, Publisher SAGE Publishing)

DOI

unavailable

PMID

unavailable

Abstract

An evaluation of several jurisdiction-wide traffic control device upgradings in Michigan was undertaken. The upgradings included only signs. A "before-after with control" experiment design was employed in the examination of general accident distributions along with a more detailed distribution of vehicle-vehicle accidents.

RESULTS of assessing the overall effectiveness of traffic control device (TCD) upgradings on a jurisdiction-wide basis were mixed at best. Due to the general variability of accident statistics and because most sites in a jurisdiction have only minor, if any, problems, potential positive results tend to be overwhelmed at sites where there may be significant improvements. It is suggested that safety-effectiveness studies are more appropriate at lower levels of aggregation.

Language: en

Keywords

MOTOR TRANSPORTATION; STREET TRAFFIC CONTROL - Legislation; TRAFFIC SIGNS, SIGNALS AND MARKINGS - Efficiency; ACCIDENTS - Analysis