Many more serious road crash injuries occur in New Zealand than statistics show, according to researcher Gabrielle McDonald from the University of Otago.
Researchers studied five years of records which revealed 15% of injuries recorded as minor were revealed by hospital data to be life-threatening.
Dr McDonald says there are potential for flaws in collecting the road injury statistics, which are based on a police officer's assessment of a patient at a crash scene.
The breadth of the categories used by police are also problematic, she says. For example, a fracture is classed as serious regardless of whether it involves a broken arm, or a back.
Dr McDonald says statistics should be based on hospital data because it is informed by medical professionals and this would result in better targeting of road safety funding.