The 100-Car Naturalistic Driving Study was undertaken with the goal of obtaining data on driver performance and behavior in the moments leading up to a crash. This type of data is not available from either of the traditional methods of studying driver behavior in regards to crashes and traffic safety, such as empirical studies and crash databases (e.g., General Estimates System and the Fatality Analysis Reporting System). Crash databases are derived from police accidents reports (PARs) and contain a wealth of data describing the non-controversial facts of the crash such as location, number of vehicles involved, type of crash, and time of day. For a variety of reasons, however, these databases do not provide good insight into the driver behavior and performance leading up to the crash. The empirical method provides a different approach to investigating driver behavior by studying how people drive under various conditions. These studies are usually conducted as highly controlled experiments using instrumented vehicles to obtain a variety of vehicle and driver performance data. Typically, these studies involve drivers operating study test vehicles for a short period of time (i.e., a few hours) in a contrived environment (i.e., either simulator or closed test track).

Naturalistic studies can be used to understand crash causation and driver behavior and supplement information learned through epidemiological and empirical approaches. Naturalistic studies include driver/subjects operating vehicles in their daily lives (e.g., commuting to work) for an extended period of time (e.g., one year). In order to collect such a dataset, the National Highway Traffic Safety Administration, the ITS Joint Program Office of the Federal Highway Administration, the Federal Motor Carrier Safety Administration, the Virginia Department of Transportation, and Virginia Tech contracted with the Virginia Tech Transportation Institute to conduct the “100-Car Naturalistic Driving Study.” This large-scale naturalistic driving study was conducted using 100 instrumented vehicles (80 privately-owned and 20 leased vehicles). This data collection effort was conducted in the Washington, DC metropolitan area on a variety of urban, suburban, and rural roadways over a span of 13 months.

This publication is considered a final report and does not supersede another publication.