Factors associated with motorcycle crashes in Western Australia: 2005 to 2011

This report presents the results of an investigation into motorcycle crashes occurring in Western Australia (WA) between 2005 and 2011. Trends in all motorcycle crash rates over the period were described and factors associated with serious injury and other severity types of motorcycle crashes at intersections were identified. Factors such as rider demographics, surface of the road, types of crash, intersection layout, traffic control signals, and posted speed limit were examined accordingly. The motorcycle crash rate gradually decreased from almost 200 motorcycle crashes to 150 motorcycle crashes per 10,000 registered motorcycles between 2005 and 2011, despite a steady increase in the number of registered motorcycles over this period. A similar trend was found for the serious injury motorcycle crash rate (which included hospitalisations and fatalities). However, the serious injury motorcycle crash rate was consistently around 4 times higher than that of all motor vehicles. Of motorcycle crashes at intersections, a great proportion of crashes were found on Fridays, peak hours, fine weather, sign controlled intersections, T-junctions, straight, sealed and dry roads, and daylight. Post speed limits at 50 and 60 km/hr accounted for more than 70 per cent of the total motorcycle crashes at intersections. More than 40 per cent of these crashes were right angle/ right turn through crashes and more than a quarter led to a serious injury crash. Males accounted for the majority of motorcycle crashes at intersections, and most riders aged between 16-44 years old. For motorcycle crashes at intersections, factors associated with serious injury crashes (fatal and hospitalisation) were identified. Motorcycle crashes at intersections which occurred on Thursdays were frequently resulting in a serious injury compared with crashes on Sundays. Head-on/right angle/right turn crashes and hit object/animal/pedestrian crashes were significantly associated with an increased risk of serious injury compared with rear end crashes. Non-collision motorcycle crashes were associated with a lower risk of serious injury and the presence of traffic lights was also significantly associated with a decreased risk of serious injury. Motorcycle crashes which occurred at night or under dark lighting conditions were frequently leading to a serious injury. In contrast, motorcyclists less frequently sustained a serious injury if the crash occurred during peak traffic hours, on wet or curved roads. The results provide Main Roads Western Australia and other road safety organisations with preliminary information about potential strategies to reduce road trauma among motorcyclists in Western Australia.