Evaluation of 2006 Pennsylvania crash data reported to the 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 Pennsylvania. MCMIS Crash File records were matched to the Pennsylvania Crash file to determine the nature and extent of underreporting. Overall, it appears that Pennsylvania is reporting about 77 percent of crash involvements that should be reported to the MCMIS Crash file. However, the vehicle type variables in the Pennsylvania data contain inconsistencies, and the MCMIS Crash severity criteria cannot be applied directly. A method using the vehicle identification number (VIN) was employed to identify the appropriate vehicles, and a surrogate was developed for crash severity. Reporting rates were highest for fatal involvements, and significantly lower for injury/transported and tow/disabled crash involvements. Smaller qualifying vehicles were less likely to be reported than larger vehicles like tractor-semitrailers. Unlike most states, bus involvements were more likely to be reported than truck involvements. Reporting rates also varied by the type of investigation agency (state police, county, or city police). Missing data rates are low for most variables, except for driver license class, roadway access, and road trafficway. Some inconsistencies between data reported to the MCMIS file and recorded in the Pennsylvania data were also noted.