Severity Dimensions in MAST are dimensions which define a convenient and common approach to summarising road safety data. It is based on the severity of injuries suffered by casualties recorded in STATS19 returns.
Severity in MAST is represented in two levels. At the top level, the Fatal and Serious levels of severity are grouped together under the commonly used umbrella term KSI. At the lower level, these levels of severity are shown separately. Slight severity is always shown as a separate set. This structure may be represented as follows:
- KSI (an abbreviation for 'Killed or Seriously Injured')
- Unknown (representing any instance where severity is missing from the STATS19 return, which should rarely if ever occur)