The average annual number of people reported killed or seriously injured (KSI) on the roads, all ages, per 10,000 resident population. This is calculated as a 3 year rolling average of people reported as KSIs divided by the latest year's population, and the resulting rate multiplied by 10,000 i.e ((KSIs in Year A + Year B +Year C)/3)/(Year c population)*100,000.
This indicator includes only casualties who are fatally or seriously injured and these categories are defined as follows: - Fatal casualties are those who sustained injuries which caused death less than 30 days after the accident; confirmed suicides are excluded. - Seriously injured casualties are those who sustained an injury for which they are detained in hospital as an in-patient, or any of the following injuries, whether or not they are admitted to hospital: fractures, concussion, internal injuries, crushings, burns (excluding friction burns), severe cuts and lacerations, severe general shock requiring medical treatment and injuries causing death 30 or more days after the accident. A casualty is recorded as seriously or slightly injured by the police on the basis of information available within a short time of the accident. This generally will not reflect the results of a medical examination, but may be influenced according to whether the casualty is hospitalised or not. Hospitalisation procedures will vary regionally.
Areas with low resident populations but have high inflows of people or traffic may have artificially high rates because the at-risk resident population is not an accurate measure of exposure to transport. This is likely to affect the results for employment centres e.g. City of London and sparsely populated rural areas which have high numbers of visitors or through traffic. Data quality may vary as different police forces use different reporting systems for collecting data. Approximately half of police forces now use the CRASH or COPA reporting systems which are reported to be more accurate as it is the system, rather than the police officer, that determines the severity of the injury. Adoption of these new reporting systems have seen an elevation in the number of injuries determined to be 'serious'. Different police forces have adopted these system changes at different times so the data for each area will be affected differently. Further information about the changes in reporting systems and affected police forces can be found here: https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/744077/reported-road-casualties-annual-report-2017.pdf
Counts for Heathrow Airport are included in the London Centre, London Region and England totals only.