One U.S. National Highway and Traffic Safety Administration study found that 80 percent of crashes involved driver inattention, while a U.K. Department of Transport study determined that 65 percent of crashes were due entirely, and another 30 percent partially, to drivers.
Isang US National Highway at Trapiko Kaligtasan Pangangasiwa pag-aaral natagpuan na ang 80 porsiyento ng mga pag-crash kasangkot driver ng hindi pag-iintindi, habang ang isang Kagawaran ng Transportasyon pag-aaral UK natukoy na 65 porsiyento ng mga pag-crash ay ganap na dapat bayaran, at ng isa pang 30 porsiyento bahagyang, sa driver.