To determine and to quantify outcome from injury demands that multiple factors 
be universally applied so that there is uniform understanding that the same 
outcome is understood for the same injury. It is thus important to define the 
variables used in any outcome assessment. Critical to defining outcomes is the 
need for a universal language that defines individual injuries. The abbreviated 
injury scale (AIS) is the only dictionary specifically designed as a system to 
define the severity of injuries throughout the body. In addition to a universal 
injury language, it provides measures of injury severity that can be used to 
stratify and classify injury severity in all body regions. Its revision, AIS 
2005 will be discussed here.