Evaluation of 2005 Connecticut 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 Connecticut. MCMIS Crash File records were matched to the Connecticut Crash file to determine the nature and extent of underreporting. However, because the Connecticut crash file does not include much of the information necessary to identify the complete set of MCMIS-reportable records, a subset of records highly likely to be reportable were identified instead. The reporting rate for this subset was 31.7 percent. For the subset, it appears that fatal involvements are more likely to be reported than nonfatal involvements, and large trucks were more likely to be reported than small trucks or buses. Of the cases that were reported to the MCMIS Crash file, missing data rates are low for almost all variables, although were 100 percent for driver license class. Some inconsistencies between data reported to the MCMIS file and recorded in the Connecticut data were also noted. Vehicle type was inconsistent in about 21 percent of the cases. Other variables that could be compared were inconsistent only in a very small number of cases.