Evaluation of 2005 Louisiana crash data reported to MCMIS crash file

Abstract

This report is part of a series evaluating the data reported to the Motor Carrier Management Information System (MCMIS) Crash File undertaken by the Center for National Truck and Bus Statistics at the University of Michigan Transportation Research Institute. The earlier studies showed that reporting to the MCMIS Crash File was incomplete. This report examines the factors that are associated with reporting rates for the state of Louisiana. MCMIS Crash File records were matched to the Louisiana Traffic Crash Report (TCR) file to determine the nature and extent of underreporting. Overall, it appears that Louisiana is reporting 56.6 percent of crash involvements that should be reported to the MCMIS Crash file. Reporting rates vary by crash severity and vehicle type. Overall, about 79.6 percent of fatal involvements are reported, compared with 57.0 percent of injury/transported involvements, and 54.7 percent of towed/disabled involvements. Crashes involving large trucks such as tractor-semitrailers or doubles combinations were more likely to be reported than crashes involving small, single-unit trucks or buses. There did not appear to be much variation in reporting rates by the type of investigation agency (state police, parish, or city police), however. Missing data rates are low for most variables, although rates are elevated for sequence of events variables, number of vehicles in the crash, and driver license class. Hazardous materials variables are also problematic, with some inconsistencies between data reported to the MCMIS file and recorded in the TCR.