Abstract
The TRISS methodology is used in by both the UK and US military trauma registries and relies on dividing casualties according to mechanism: penetrating or blunt. The UK and US military trauma registries use the original coefficients devised in 1987 and it is not clear how either registry analyses explosive casualties according to the TRISS methodology. This study aims to use the UK military trauma registry (JTTR) to calculate new TRISS coefficients for contemporary battlefield casualties injured by either gunshot or explosive mechanisms. The JTTR was searched for all UK Casualties injured or killed between 2003 and 2014. A logistic regression analysis was performed to devise new TRISS coefficients, these were then used to re-examine survival over the 12 years of the study. Comparing the predictions from the GSW TRISS model to the observed outcomes, it demonstrates a sensitivity of 98.1% and a specificity of 96.8% and an overall accuracy 97.8%. With respect to the explosive TRISS model, there is a sensitivity of 98.6%, a specificity of 97.4% and an overall accuracy of 98.4%. When this improved TRISS methodology was used to measure changes in survival, there was a sustained improvement over the 12-year study period.
