2. General Requirements
Never be sequenced as the first-listed or principal diagnosis
Intended to provide data for injury research and evaluation of injury prevention strategies.
No National requirement for mandatory ICD-10-CM external cause code reporting.
3. General External Cause Coding Guidelines
Used with any code in the range of A00.0 – T88.9 & Z00-Z9920.
External cause code used for length of treatment
Use the full range of external cause codes
Assign as many external cause codes as necessary
The selection of the appropriate external cause code
External cause code can never be a principal diagnosis
Combination external cause codes –EG; W18.09
No external cause code needed in certain circumstances .EG; T36.0X1-
poisoning by penicillins, accidental (unintentional)
4. Place of Occurrence Guidelines
Category Y92,
Place of occurrence of the external cause – secondary external cause
codes
.Only assigned once, at the initial encounter for treatment.
No 7th character If place is not stated or not applicable, do not code
5. Activity Code
Y93, Activity Code,
Describes the activity at the time of the injury
Only assigned once, at the initial encounter for treatment.
Not applicable to poisonings, adverse effects, misadventures or sequela.
If activity is not stated or not applicable, do not code Appropriate for use with external cause and
intent codes if provides additional information
6. Sequncing
External cause code(V,W,X,Y) Accidental, unintentional(assault),
intentional(suicide),undetermined intent
Place of occurance ( Y92)
Activity (Y93)
Status (Y99)
7. Multiple External Cause Coding
Guidelines
More then one external cause code is required to fully describe the external
cause of an illness or injury
Priority Sequencing:
Child and adult abuse
Terrorism
Cataclysmic events
Transport accidents
Activity and external cause status codes assigned after all causal (intent)
codes
8. Child and Adult Abuse
Abuse, neglect and maltreatment are all classified as assault
Only code if confirmed abuse
If perpetrator is known, also code from Y07, Perpetrator of maltreatment and neglect.
9. Sequelae (late Effects)
Sequelae external cause codes
Reported with 7th digit “S” and should be used with any report of a late
effect resulting from a previous injury.
Sequela external cause code with a related current injury
Never used with a related current nature of injury code
Use of sequela external cause codes for subsequent visits
Used when a late effect of the initial injury is being treated, not for
subsequent visits for follow-up care of the injury when no late effect of
the injury has been documented
10. Terrorism Guidelines
Cause of injury identified by the Federal Government (FBI) as
terrorismCode from Y38,
Terrorism should be used as the firsts listed external cause code
More than one Y38 code may be assigned if the injury is the result of
more than one mechanism of terrorism
Cause of an injury is suspected to be the result of terrorism
Do not code from Y38, suspected is coded as assault
Code Y38.9, Terrorism, secondary effects Conditions occurring
subsequent to the terrorist event
It is acceptable to code from Y38.9 and another Y38 category if there is
an injury due to the initial terrorist event and an injury that is a
subsequent result of the terrorist event
11. Unknown or Undetermined Intent
If the intent of the cause of injury is unknown or unspecified, code as
accidental intent
All transports are assumed accidental intent.
Use of undetermined intent
External cause codes for events of undetermined intent are ONLY for
use if the documentation in the record specifies that the intent cannot
be determined
12. External Cause Status Code Category Y99
Should be used whenever any other external cause code is assigned for
an encounter, except listed exceptions.
Exceptions: poisonings, adverse effects, misadventures or late effects.
Codes are used to indicate the work status at the time of the event . Ex:
military activity, work, student, volunteer, etc.
Do not use if no other external cause codes used
Only used at the initial encounter If status is not stated or not
applicable, do not code
