Crash Involved Vehicle Type dimensions
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The Crash Involved Vehicle dimensions indicate whether or not each crash involved any vehicles of a specified variety, and are therefore a convenient way to represent vehicle type in crashes reports. MAST provides seven distinct dimensions of this kind, one for each principal variety of vehicle.
The vehicle varieties used are based on the groupings employed by the Vehicle Type dimension.
The Crash Involved Vehicle dimensions, and the variety of vehicle they encompass, are:
- Crash Involved Vehicle PC (pedal cycles only)
- Crash Involved Vehicle MC (motorcycles of all sizes)
- Crash Involved Vehicle Bus (buses and/or coaches)
- Crash Involved Vehicle Car (cars, taxis and/or minibuses)
- Crash Involved Vehicle Goods (goods vehicles of any size, including car based vans)
- Crash Involved Vehicle Misc Motor (any type of motorised vehicle other than those specified above)
- Crash Involved Vehicle Misc NonMotor (any type of non-motorised vehicle other than pedal cycles, including ridden horses)
- Crash Involved Senior Driver (drivers/riders aged 65 years or older, excluding pedal cyclists, included whether or not the driver/rider was injured)
- Crash Involved Young Driver (drivers/riders aged 16 to 24 years, excluding pedal cyclists, included whether or not the driver/rider was injured)
Top level structure
The highest level of the hierarchy in every Crash Involved Vehicle dimension contains a boolean value which indicates whether or not any vehicle of the specified variety was involved:
- No_[Type] , for no vehicle of the specified variety
- [Type]_Involved , for one or more vehicles of the specified variety
Four of the Crash Involved Vehicle dimensions (PC, Bus, Misc Motor and Misc NonMotor) contain only this straightforward choice, with no further detail available.
Detailed structure
Three of the Crash Involved Vehicle dimensions (MC, Car and Goods) have additional hierarchy levels below [Type]_Involved which break down the general varities into more specific vehicle types.
It is entirely possible for a crash to involve vehicles which are of the same general variety but different detailed types. Each level of detail below the highest must allow for this possibility. This is done by including options which are named something along the lines of [Type]_Multiple . For example:
- Goods_Multiple includes crashes which involved both light and heavy goods vehicles (for example, both an articulated lorry and a car based van)
- Goods_Heavy_Multiple includes crashes which involved heavy goods vehicles of different weight classes (for example, one truck below 7.5 tonnes weight and another above 7.5 tonnes weight)
Combining multiple Crash Involved Vehicle dimensions
It is possible to combine multiple dimensions of this kind in the same report, but it is important to understand the consequences of doing so. The most important thing to bear in mind is that MAST reports never employ double counting, unlike many paper based reports such as some of those available in RRCGB.
If filters are applied to more than one Crash Involved Vehicle dimension in the same report, then only crashes which involved all of the specified types will be included.
If multiple Crash Involved Vehicle dimensions are added as categories or series in the same report without filters applied, then every possible combination of presence and absence of every specified variety of vehicle will be shown as a distinct result.
