Pedal cycle injuries in NSW: A comparison of data sources

Road & Transport Research, Dec 2003 by Voukelatos, Alex, Rissel, Chris, Campbell, Fiona

Hospital data

Data from the ISC were accessed via the HOIST (Health Outcomes and Informational Toolkit) database tool (HOIST 2002) and analysed using the SAS statistical package (SAS 1997). In particular, the ISC database for NSW in 1999-2000 was analysed, applying various filters to investigate comparability with the RTA data.

Filter 1 - Road vehicle accidents in which an injury was sustained: Motor-vehicles and pedal cycles

This initial filter was applied to ISC data in order to estimate the relative contribution to road vehicle accident-related injuries requiring hospitalisation of motor vehicles compared to pedal cycles.

For motor vehicles E-codes E810-E819 plus E822E823 were included. For pedal cycles what codes to include is more complex. all ?-codes have a 4th digit extension to indicate the injured party. For E-codes E810-E819 and E822-E823, the 4th digit extension '.6' relates to pedal cyclists being injured. Clearly, if a pedal cyclist is injured a pedal cycle must have been involved in the accident, so for pedal cycles filter 1 includes E-codes E810.6, E811.6,..., E819.6, as well as E822.6 and E823.6. There is an additional E-code, E826, that relates to pedal cycle accidents not involving a motor vehicle. This code includes pedal cycle accidents where injury was from falling off the pedal cycle or the pedal cycle being overturned, among many other specific circumstances (NSW HealthICD9-CM code listing). Generally this code is not included when investigating motor vehicle accidents. However, we reasoned that this code, specifically E826.1, pedal cycle accident where the injury was to a pedal cyclists, will include the non-collision motor vehicle accidents involving pedal cycles which are not captured by RTA data. Riding a pedal cycle is a skilful coordination of balance, muscle strength and foresight. However, it is possible for a pedal cycle accident to be caused by a motor vehicle without there being a direct collision or contact, and the incident may be made more dangerousby poor road conditions. While all the cases coded under E826.1 will not be of this type, some will. all subsequent filters for pedal cycles apply this reasoning, and include data both with and without the code E826.1 for reasons of comparison.

Filter 2 - Who was injured in motor-vehicle and pedal cycle accidents: Motor-vehicle occupants and pedal cyclists

This filter was applied to examine who was injured in motor vehicle and pedal cycle accidents: motor-vehicle occupants versus pedal cyclists. For injuries to motor vehicles occupants, the appropriate 4th digit subdivision E-codes were: .0 (injury to driver),. 1 (injury to passenger), .2 (injury to motorcyclist), .3 (injury to passenger on motorcycle) of ?-codes E810-E819, plus E822 and E823 (e.g. 810.0, 810.1, 810.2, 810.3, ..., 823.2,823.3). For injuries to pedal cyclists this filter is the same as filter 1. This filter is a crude correlate to those motor vehicle and pedal cycle accidents likely to be reported by the RTA, and so can be compared to RTAdatainTflWe�.