A research symposium has been told fatigue and distraction are bigger factors in crashes than previously believed.
The two day Automobile Association Research Foundation event into driver inattention, distraction and fatigue began in Wellington on Monday.
Keynote speaker Professor Thomas Dingus, the director of the Virginia Tech Transportation Institute, says several studies conducted by the institute show human performance and behaviour contribute to more than 90% of crashes.
He says 10% of all drivers created 50% of the crash risk.
Professor Dingus says fatigue could be responsible for 20% of all crashes and distraction up to 50%.
He says a person who is moderately fatigued is six to eight times more likely to crash, and teenagers are four times more likely to be involved in a distraction crash or near miss.
Research also shows truck drivers are 23 times more likely to crash if texting while driving, and that at anyone time four percent of truck drivers are moderately fatigued.
Minister suspects under reporting in fatigue stats
Meanwhile, the Associate Transport Minister, Nathan Guy, says the Government is aware that driver fatigue and inattention are significant factors in road crashes, with fatigue probably playing a greater role in crashes than current data indicates.
He says between 2006 and 2010, fatigue was identified as the cause of 13% of fatal crashes and 7% of serious injury crashes.
International research, he says, suggests the incidence of fatigue as a cause of crashes is being under-reported and that a more accurate figure may be as high as 25% in the case of fatal crashes.