Drug Use and Involvement in a Safety-Critical Event

Abstract

This study used the Naturalistic Truck Driving Study data set to test the feasibility of applying naturalistic data to evaluation of the relationship between prescription (Rx) and over-the-counter (OTC) drug use and involvement in a safety-critical event (SCE). The risk of drug use was calculated by comparing SCEs and baseline epochs that occurred within a drug's half-life with SCEs and baseline epochs that did not occur within a drug's half-life (for the same half-life period). This research found that nearly 97% of commercial motor vehicle drivers used an OTC drug at least once (mostly caffeine), and 25% used at least one Rx drug. Furthermore, Rx and noncaffeine OTC drug use was not associated with an increased or decreased risk of involvement in an SCE. As caffeine was the only drug classification used multiple times by many drivers, this odds ratio analysis was the only analysis performed. Caffeine use while driving was found to be associated with a decreased risk of SCE involvement in all seven half-lives (half-life odds ratios ranging from 0.44 to 0.66). This project illustrated the feasibility of using a naturalistic driving approach to assess the risk associated with Rx and OTC drug use while driving. It is possible that analyses for specific medications could be performed with a sufficiently large sample of drivers who used each classification of drug.