Definitions and Jargon buster

The following terms and definitions are used in leaflets and other materials produced by the SERP:

• Casualty & Collision Data: In order for collisions to be included in our statistics they have to take place on the public highway in Essex, Southend or Thurrock, and result in an injury to a person, and be reported to the police.
• SERP area: The geographic area covered by the Safer Essex Roads Partnership, comprising all public highways (including those managed by Highways England) in the 12 districts covered by Essex County Council, and the unitary authorities of Southend-on-Sea and Thurrock. This is also the same area covered by Essex Police and Essex Fire & Rescue Service.
• KSI: ‘Killed or Seriously Injured’ – Refers to the severity of injury for any person involved in a collision. The collision severity is that of the most severely injured person involved.
• Severity ratio: Percent of all casualties who were either killed or seriously injured (e.g. if 100 people were injured, 10 of them seriously or fatally, the severity ratio would be 10%).
• Fatal casualty: Where death occurs within 30 days of the collision and as a result of injuries sustained in the collision. Excludes death by natural causes and confirmed suicide.
• Serious casualty: Fracture, internal injury, severe cuts, crushing, burns (excluding from friction), concussion, shock requiring hospital treatment, anything requiring treatment as an in-patient.
• Slight casualty: Sprains, bruises, slight cuts, minor shock.
• Child: Any person aged 0-15 years. This age threshold was decreased from 18 years in April 2015 to remove overlap between school children not allowed to drive motor vehicles, and 16-17 year olds who are.
• Young person: Any person aged 16-25 years.
• Young driver: Usually refers to car drivers aged 17-25 years, unless otherwise stated.
• Older person: Any person aged 76 years or older. This age threshold was increased from 65 years in April 2015 after an analysis of collisions involving older people showed that age-related risk undergoes a concerted increase from the age of around 75 years onwards.
• P2W: Stands for ‘Powered 2 Wheeler’, includes any form of motorcycle.