MTA What we measure
An Abbreviated Injury Scale (AIS) score of one represents a minor injury, while an AIS score of six represents an injury that is not survivable. This contributes to the overall Injury Severity Score (ISS) for every patient, rated on a scale from 0 to 75. The ISS score is used in conjunction with other physiological parameters, including:
- Glasgow Coma Score (GCS) - a measure of level of consciousness
- co-morbidities - the presence of at least one additional disorder concurrent with a primary disorder.
The PS (probability of a patient surviving until discharge or 30 days) for each injured patient is measured. For example, if a patient has a calculated risk-adjusted probability of survival of 80%, this means that for every 100 patients with the same severity of injury and other parameters, 80 are expected to survive and 20 expected to die. This calculation is based on the historical records of tens of thousands of trauma patients whose injuries and outcomes have previously been captured on the TARN database.