Medical conditions as a contributing factor in crash causation

Between 2008 and 2010 CASR undertook a study to determine the proportion of casualty crashes resulting in admission to hospital that were directly associated with the effects of a medical condition or an acute medical event. The study involved examination of the hospital medical records for drivers, riders, pedestrians and cyclists involved in crashes on public roads in South Australia who presented to the Royal Adelaide Hospital for four hours or more during the three year period. A total of 1,490 medical records were accessed. These records were matched with a number of other data sources including Vehicle Collision Records generated by South Australian Police, licensing records from the SA Department of Motor Registration and drug and alcohol screening records generated by the Forensic Science Centre of SA. This detailed examination of the circumstances surrounding each person’s involvement in a crash enabled identification of those crashes that occurred as the direct result of a medical condition or acute medical event, as opposed to those for which a crash participant’s pre-existing medical condition(s) were unrelated. The study found that more than 10% of the crashes involved an active participant with a confirmed medical condition or acute medical event considered to be a contributing factor in the crash causation. This paper will outline the major findings of the study including the medical conditions found to have directly contributed to the crash, licensing considerations before and after crash involvement and the crash types commonly observed.