Injury Severity Score (ISS)

Overall score for multitrauma

Step 1

Assign an Abbreviated Injury Scale (AIS) score to each of the six body regions: Note: only the highest AIS score in each body region is used.

Step 2

Square the three highest AIS scores and take the sum of these three: this is the ISS.


The ISS correlates linearly with mortality, morbidity, hospital stay and other measures of severity.