EVN — Event Type
HL7 v2.5.1 Event Type segment reference
Describes the trigger event for ADT messages. Identifies when and who recorded the event.
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The table below lists the commonly used fields of the EVN (Event Type) segment. Field positions follow the HL7 v2.5.1 specification.
| Field | Name | Type | Len | Use | Description |
|---|---|---|---|---|---|
| EVN-1 | Event Type Code | ID | 3 | O | Event trigger code. Redundant with MSH.9.2 in v2.5+.e.g. A01 HL7 table 0003 |
| EVN-2 | Recorded Date/Time | TS | 26 | R | When the event was entered into the source system.e.g. 20240315080500 |
| EVN-6 | Event Occurred | TS | 26 | O | When the event actually happened (may differ from recorded time).e.g. 20240315080000 |
Use column: R Required · C Conditional · O Optional. Type column uses HL7 data-type codes (ST = string, NM = numeric, TS = timestamp, CX = extended composite ID, XPN = extended person name, and so on).