A one-year on-road vehicle study recently completed by the Virginia Tech Transportation Institute (VTTI) that tracked 100 vehicles in the Northern Virginia/Metropolitan Washington D.C. area found that driver inattention and fatigue lead to more accidents that previously thought.

Nearly 80% of the 82 crashes and 65% of the 761 near-crashes recorded by the study involved driver inattention just prior (within 3 seconds) to the onset of the accident or near-accident scenario. On top of that, fatigue was discovered to be a contributing factor in 12% of all crashes and 10% of all near-crashes. This marks a dramatic increase over most current estimates that place fatigue-related crashes at 2- to 4% of total crashes.

“If you don’t have good information about why crashes occur and why fatalities occur, you can’t really solve the problem,” said VTTI director Tom Dingus. “This study and its results represent a new and unique approach to understanding driver behavior.”

The National Highway Traffic Safety Administration (NHTSA), Virginia Tech, Virginia Department of Transportation (VDOT), and Virginia Transportation Research Council (VTRC) helped sponsor the study, which gathered information on the 100 drivers unobtrusively through five channels of digital compressed video and a variety of sensors that recorded vehicle state and kinematic information. Data collection resulted in approximately 2,000,000 vehicle miles of driving, totaling over 42,000 hours of data with 241 primary and secondary driver participants.

Termed “The 100-Car Study,” VTTI researchers compiled an “event” database from all the data collected and found that driver inattention to the forward roadway was the primary contributing factor in most crashes, with 93% of rear-end-striking crashes involved driver inattention.

Driver inattention includes such things as drivers eating, writing, conversing with a passenger or looking away from the forward roadway at rear-view mirrors, objects in the vehicle or objects outside. The study also revealed that the use of hand-held wireless devices was associated with the highest frequency of secondary task distraction-related events and was among the highest frequencies for crashes.