MTA Methodology

Once gathered, data is verified, triangulated and anonymised by the MTA coordinators in the hospitals and directly entered onto the secure Trauma Audit and Research Network (TARN) portal for injury coding and analysis. TARN focuses on more severely injured trauma patients with potential life-changing or life-threatening injury. Injured patients who die in advance of reaching hospital are not included.

When auditing the management of major trauma, it’s important to have a method for grading the severity of the trauma. Otherwise, it would not be possible to distinguish between a death that could have been prevented with better care processes, and a death that was inevitable due to the severity of injury.

Each injury is coded using an internationally agreed standardised coding system for trauma — the Abbreviated Injury Scale (AIS) dictionary, produced by the Association for the Advancement of Automotive Medicine (AAAM, 2005). Each injury is scored between one and six based on its severity to calculate the probability of survival (PS) for each injured patient.