The impact on pedestrian injuries is also greatly affected by vehicle speed: as a car's speed increases from 30 to 50 kilometres per hour, the likelihood of a pedestrian death increases by a factor of eight.
车辆速度对行人受伤也有很大影响：如果汽车车速从每小时30公里增加到50公里，造成行人死亡的可能性则增加七倍。