And it is indeed moving forward to develop and test an IRT model. In July, FMCSA delivered a report to Congress on its “corrective action plan” for CSA outlining how it’s implementing the NAS recommendations. A variety of violations across different areas will tank your scores much worse than a record showing just one area where you’re falling short. The new methodology is not about trying to predict crash risk, but focusing on “safety culture” at a motor carrier.This new methodology is happening, and the industry needs to start thinking about it.But NAS found that some of the details of how those numbers are calculated weren’t really scientifically based, or as the report said, “ad hoc and not fully supported by empirical studies.” The scientists on the panel say IRT is a more scientific way to approach these safety scores. IRT is widely used in the education field (think SAT tests), and has been used for policy decisions in areas such as hospital rankings.Īt the heart of CSA is the Safety Measurement System, used to identify commercial motor vehicle carriers at high risk for future crashes. The NAS panel’s report recommended that FMCSA develop a “more statistically principled approach” for the task, based on an item response theory (IRT) model. The New CSA Methodology Will Use Item Response Theory Using measures that are not reflective of a carrier’s efforts to improve its safety performance over time.Ģ.Using measures that are not predictive of a carrier’s future crash frequency.Using measures that are sensitive to effects from one or more individual states.Including carriers that have very different tasks in the same peer groups.Not accounting for crashes where the motor carrier is not at fault.

Csa violation chart