The word 'risk' is used to express the safety level in traffic.
Risk: comparison of safety
To compare the number of crashes of various groups, such as countries, modes of transport or road types, we can relate the number of casualties to mobility. This involves determining the risk: the number of casualties per distance travelled (e.g. kilometres travelled). Risk therefore not only takes into account the number of casualties (in a group), but also the distance travelled (by that group).
Risk of ...?
'Risk in traffic' can be defined as the risk of a crash, of a road death or of a serious road injury. risico SWOV mostly works with the definition 'the risk of being a road crash casualty'. The definition 'risk of a crash is not used, among other things because a crash can involve various types and numbers of casualties, making a crash a more complex unit than 'casualty'. Often the number of casualties is also more relevant than the number of crashes, because, overall, the prevention of casualties is more important.
Which data is necessary to determine risk?
Preferably, mobility data is used to calculate risk. If no mobility data is available, other data ( size of the vehicle fleet, size of the population, distance travelled by motor vehicles) can be used instead of mobility data.
Ideally, risk is calculated using the real numbers of road deaths and serious road injuries. For some analyses insufficient characteristics of the casualties are available if the real numbers are used. In those cases the analysis can be made using the registered numbers if they do contain the rquired characteristics. However, the results must be interpreted with care; one should consider that the results do not fully reflect the actual situation.
More information?
More detailed information can be found in the archived SWOV Fact sheet Risk in traffic.
More about road user mobility.
In the report Data sources; Comprehensive overview you can find more information about the registration rate.
