Serious injury in Victoria: Part 1: development and validation of a severity of injury measure using Victorian administrative data Part 2: trends in serious road traffic injury hospitalisations, Victoria, 2000-2012/13

Angela Jayne Clapperton, Angelo Dominic D'Elia, Lesley Margaret Day

Research output: Book/ReportCommissioned ReportResearch


Background and aims: Injury severity measurement is important for monitoring trends in injury and for providing reliable information to inform policy and injury prevention practice. The first aim of this research was to use Victorian specific data to investigate different methods of calculating one particular severity measure - the International Classification of Diseases Injury Severity Score (ICISS). The ICISS is a “threat-to-life” injury measure which when applied to administrative data allows the identification of serious injury hospitalisations by identifying cases with a high probability of death. The second aim was to analyse the trend and pattern of Victorian serious road traffic injury hospitalisations using the best method for calculating the ICISS.

Method: Data for the 10-year period 2003/04-2012/13 were extracted from the Victorian Admitted Episodes Dataset (VAED) which contains information on all patients admitted to Victorian hospitals. Different methods of calculating International Classification of Diseases Injury Severity Scores (ICISSs) from the VAED were employed and tested. Methods included adjusting the scores for age, comorbidity and the presence of multiple injury diagnoses. Tests were undertaken to determine the best ICISS method for monitoring serious injury in Victoria – in other words, the score that most accurately predicts mortality.

Results and Discussion: ICISSs calculated using only the injury diagnosis with the highest threat to life (worst injury method) demonstrated slightly better ability to predict mortality than corresponding scores calculated using all recorded injury diagnoses. On a practical level, an advantage of the worst injury approach is that it can be used for datasets where only a relatively small number of injury diagnoses are provided. The inclusion of age in the calculation significantly improved predictive ability and the inclusion of age and comorbidity improved the performance of ICISSs to the greatest degree. However, reliance on age adjustment only may be preferable to comorbidity adjustment. Comorbidity information may not be recorded at all, or may not be systematically recorded in administrative datasets, thereby potentially introducing bias if it is used. Therefore, the Victorian specific ICISSs, adjusted for age and using only the injury with the highest threat to life, should be used to define serious injury hospitalisations. Further, as the ICISS is a threat-to-life measure, injury severity measures that capture injury morbidity should be considered as part of a suite of indicators.

Serious road traffic injury hospitalisations (2000-2012/13): Over the most recent 13-year period (2000-2012) there were 112,915 road traffic injury hospitalisations, of which 17,712 (16%) were classified as serious using the newly derived measure. Car occupants accounted for more than half of these serious injury hospitalisations (56.6%), followed by motorcycle riders (14.3%), pedestrians (14.2%) and pedal cyclists (9.1%). There is an overall increasing trend in serious injury, most notably for motorcyclists and cyclists.
Original languageEnglish
Place of PublicationClayton Vic Australia
Commissioning bodyRoads Corporation (trading as VicRoads) (Victoria)
Number of pages32
Publication statusPublished - 2014


  • Serious injury
  • Road trauma

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