Introduction Triage is a key principle in the effective management of major incidents. There is limited evidence to support existing triage tools, with a number of studies demonstrating poor performance at predicting the need for a life-saving intervention. The Modified Physiological Triage Tool (MPTT) is a novel triage tool derived using logistic regression, and in retrospective data sets has shown optimum performance at predicting the need for life-saving intervention.

Materials and methods Physiological data and interventions were prospectively collected for consecutive adult patients with trauma (>18 years) presenting to the emergency department at Camp Bastion, Afghanistan, between March and September 2011. Patients were considered priority 1 (P1) if they received one or more interventions from a previously defined list. Patients were triaged using existing triage tools and the MPTT. Performance was measured using sensitivity and specificity, and a McNemar test with Bonferroni calculation was applied for tools with similar performance.

Results The study population comprised 357 patients, of whom 214 (59.9%) were classed as P1. The MPTT (sensitivity: 83.6%, 95% CI 78.0% to 88.3%; specificity: 51.0%, 95% CI 42.6% to 59.5%) outperformed all existing triage tools at predicting the need for life-saving intervention, with a 19.6% absolute reduction in undertriage compared with the existing Military Sieve. The improvement in undertriage comes at the expense of overtriage; rates of overtriage were 11.6% higher with the MPTT than the Military Sieve. Using a McNemar test, a statistically significant (p<0.001) improvement in overall performance was demonstrated, supporting the use of the MPTT over the Military Sieve.

Discussion and conclusions The MPTT outperforms all existing triage tools at predicting the need for life-saving intervention, with the lowest rates of undertriage while maintaining acceptable levels of overtriage. Having now been validated on both military and civilian cohorts, we recommend that the major incident community consider adopting the MPTT for the purposes of primary triage.