Evaluation of the Victorian state adult pre-hospital trauma triage criteria.

BACKGROUND Pre-hospital trauma triage criteria are used to expedite the transport of severely injured patients to major trauma services. The current Victorian adult pre-hospital trauma triage criteria consist of physiological, anatomical and mechanistic elements. The purpose of this study was to evaluate the performance of the current triage criteria and, if necessary propose refined criteria to improve the under and over-triage rates. METHODS The study was conducted in Melbourne, Victoria, which has a fully integrated State Trauma System. Trauma data was sourced from the pre-hospital Victorian Ambulance Clinical Information System and the Victorian State Trauma Registry. Confirmed major trauma was defined at hospital discharge as one or more of death, ISS>15, ICU ventilation or urgent surgery. Data was matched through probabilistic linkage. The triage criteria were evaluated using multivariate logistic regression and classification tree modelling. Diagnostic statistics, including sensitivity and specificity were calculated to assess triage performance. RESULTS Over 12-months there were 1166 'confirmed major trauma' patients and 44,166 'non-major trauma' patients. Evaluation showed the current triage criteria needed refinement, and multiple revised pre-hospital trauma triage models were constructed. Based on the best overall combination of diagnostic statistics, a revised model was chosen with a sensitivity of 97.8% (vs. 95.3% in the current model), a specificity of 82.7% (vs. 62.7%) and an accuracy of 83.0% (vs. 63.4%). The over-triage rate was 17.3% (vs. 37.3%) and the under-triage rate was 2.2% (vs. 4.7%). CONCLUSIONS Evaluation showed that the specificity and sensitivity of the current trauma triage criteria could be improved. The implementation of a revised triage model should identify more confirmed major trauma patients. Likewise, over-triage of non-major trauma patients to major trauma services would be significantly reduced. The refined criteria should also decrease discretionary decision-making by paramedics in the field.