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Crash Report Development Guidance

Mutually Exclusive Attributes:
For proper recording and consistency, attribute sets must be “mutually exclusive”.  That is, they should not offer more than one selection that can be true at the same time. A lack of mutual exclusivity within a data element’s attribute set can easily occur when attempting to merge data elements to save space or when incorporating SAFETYNET related elements and attributes into the primary crash report. A lack of mutual exclusivity will result in inconsistent data recording and no means to accurately map to SAFETYNET. The photos below show vehicle examples and possible attributes for each that would be in conflict if included within the same data element. See a more detailed example.

Single Unit Truck 3 or more axles
Single Unit Truck 3 or more axles
Record as a Farm Vehicle or
Single-Unit Truck 3 or more Axles?
Record as a Maintenance Vehicle or
Single-Unit Truck 3 or more Axles?
Bus w/ Seats for 9 or more
Single-Unit Truck 2 axles, 6 tires
Record as a Van or
Bus w/ Seats for 9-15 passengers?
Record as a Pickup or
Single-Unit Truck 2 Axles, 6 Tires?