Colorado overall crash severity

Explanation

The first thing to know is that Crash Magic does not change the values of any of your “stored” data fields. What is entered/imported is stored just as it is provided. PdMagic has created calculated fields (names all start with “calc”) that aggregate the available severity fields to make accessing them more consistent. For the purpose of this article, references to “Crash Magic” refer to the Crash Magic DR3447 configuration, the standard configuration used for our Colorado clients.

The NHTSA MMUCC standard defines injury status using the “KABCO” scale.  The DR3447 form and Crash Magic utilize the same values.  These are the values on that scale:

(K) Fatal Injury
(A) Suspected Serious Injury
(B) Suspected Minor Injury
(C) Possible Injury
(O) No Apparent Injury

The DR3447 form and Crash Magic store the following severity-related fields:

• Crash level: NumberKilled
• Crash level: NumberInjured
• Occupant level: InjurySeverity

Crash Magic fields: In order to support legacy data sources (pre 2021) as well as the CDOT and some other crash extract formats, Crash Magic stores the following additional crash level fields in the database:

• CDOT_InjuryLevel_0, 1, 2, 3, 4 fields. Each of these fields contains the number of instances of each injury severity type. (reverse order of KABCO)
  The standard CDOT CSV extract only contains information for up to 3 vehicles and their respective drivers.  This means that using a per-occupant calculation will miss any injuries or fatalities involving a non-driver.  To address this shortcoming, CDOT has added these 5 fields which contain counts across all of the occupants, even those not exported in the their CSV. These fields are necessary to consider when using CDOT CSV as the data source. These fields are not and should not be populated if the data source is the Colorado DOR XML format, as Crash Magic will provide these counts through calculated fields.
• CrashSeverity_Legacy
  This field provides the ability to override a crash level severity when the individual KABCO component fields are not available.  It is most often used for data migrated from significantly older systems or when an agency chooses to correct existing older data without KABCO values available. This field will and should only be populated as a last option.

Crash Magic calculated fields: Crash Magic provides a number of calculated fields to report severity information.  These fields utilize whatever values are available in the database, in a specific order. They all start with “calc” to indicate that they are not stored fields.

• CalcSeverity – A value representing the highest KABCO injury level in the crash
  This field looks first for the CrashSeverityLegacy field.  If that field is not populated, it proceeds to look for the 5 CDOT_InjuryLevel_n fields. If any of those fields are populated, their value is used to determine the overall CalcSeverity. Finally, if none of these secondary severity fields are populated, the configuration examines all of the Occupant records to determine the highest level of severity and returns that. This enables an overall severity field to be available for most crash records.
• Severity instance counts.  The following calculated fields provide a sum of each occupant record severity type. (i.e. how many fatalities in the crash; how many serious injuries in the crash; etc.) These calculated fields will check to see if there is a CDOT_InjuryLevel and use that value directly. Otherwise, the preferred method of summing the values in the occupant records will be used.
  • CalcNoApparentInjuries,
  • CalcPossibleInjuries
  • CalcSuspMinorInjuries
  • CalcSuspSeriousInjuries
  • CalcFatalities
• Internal injury and fatality flags. Every Crash Magic configuration needs two flags to indicate whether a crash was an injury or a fatal crash.  The program uses these values to render appropriate symbols in collision diagrams and some reports use them as a simple PDO/Injury/Fatatility indicator.  Since these are just true/false flags, they can not help determine KABCO values.  However, they are the most backward-compatible severity values and should provide the correct values even when KABCO values are not available in your data. These fields are not prefixed with “Calc” as they are part of a long list of internal fields used by all Crash Magic configurations.
  • _IsInjury
    This calculated field will be true if any of CalcPossibleInjuries, CalcSuspMinorInjuries or CalcSuspSeriousInjuries is greater than 0. It will also be true if NumberOfInjuries is > 0.  Finally, this field always be false if the crash had a fatality.
  • _IsFatality
    This calculated field will be true if CalcFatalities is greater than 0 or of NumberOfFatalities is greater than 0.

Important: The CDOT DR3447 “INVESTIGATING OFFICER’S CRASH REPORTING MANUAL” specifies that “Possible Injury” should not be included in the “Number Injured” count on the form.  However, it also acknowledges that the NHTSA MMUCC standard calls for this value to be included in the Number Injured total. These two specifications are in conflict. Crash Magic follows the MMUCC standard unless a request is made by a client to follow the DOT specification for their agency. This calculation applies to the _IsInjury field which is used for collision diagram symbols.

While MMUCC (4th edition) calls for Possible Injury severities to be counted in this total, the Possible Injury severity is excluded from this count on the DR3447 to stay consistent with the method of counting that has been in place in Colorado since 2006.