CMU’s Greenhouse Leads Review Panel, Report on Safety Measurement System at Federal Motor Carrier Safety Administration

Joel Greenhouse, professor, Department of Statistics, Carnegie Mellon University, recently led a 12-member review panel on the Federal Motor Carrier Safety Administration’s (FMCSA) safety measurement system (SMS) – the program used to identify commercial motor vehicle carriers at high risk for future crashes. Comprised of academicians, research scientists, and transportation experts from across the country, the group conducted a study and produced a subsequent report titled Improving Motor Carrier Safety Measurement, which found that while the SMS is conceptually sound, several aspects of its implementation need improvement.

In the congressionally-mandated report, the panel recommends that FMCSA should develop a more statistically principled approach based on an item response theory (IRT) model – one that has been successfully applied in other fields like hospital rankings. Should the model demonstrate accuracy in identifying suspect motor carriers, the group advises FMCSA to replace its current SMS.

Additional recommendations include:

-FMCSA should continue to collaborate with states and other agencies to improve data collection on vehicle miles traveled (by state and month) and crashes

-FMCSA should research ways of collecting data on motor vehicle carrier characteristics – things like driver turnover rates, type of cargo, method and level of compensation – to name a few

Commercial motor vehicle (CMV) carriers are responsible for moving freight and passengers over the nation’s vast network of highways, and doing so in a safe manner. Approximately 100,000 fatality- or injury-causing crashes involving large trucks and buses occur in the United States each year. More than 3 million CMV roadside inspections take place yearly and are performed by specially trained inspectors across 900 potential violations of safety regulations. FMCSA uses data collected during these inspections to identify motor carriers that are operating unsafely and placing the public at heightened risk for future crashes.