NK1 — Next of Kin / Associated Parties
Follows PID in ADT messages. Repeatable — one segment per next of kin or associated party.
The NK1 segment contains information about the patient's next of kin and other associated parties such as emergency contacts, guarantors, and authorized representatives. Multiple NK1 segments can appear in a message for different associated parties.
Real-World Context
NK1 drives emergency notification and consent workflows. The relationship code in NK1.3 determines who can authorize treatment on behalf of a patient. When emergency contacts are not receiving calls, the problem is usually a missing or incorrect phone number in NK1.5 or NK1.6, or the contact role in NK1.7 not matching what the nurse call system expects.
Field Reference
Click any row to see the full description, common values, and troubleshooting tip.
| # | Field Name | Type | Req | Max Len | |
|---|---|---|---|---|---|
| 1 | Set ID - NK1 | SI | R | 4 | ▶ |
| 2 | Name | XPN | O | 250 | ▶ |
| 3 | Relationship | CE | O | 250 | ▶ |
| 4 | Address | XAD | O | 250 | ▶ |
| 5 | Phone Number | XTN | O | 250 | ▶ |
| 6 | Business Phone Number | XTN | O | 250 | ▶ |
| 7 | Contact Role | CE | O | 250 | ▶ |
| 8 | Start Date | DT | O | 8 | ▶ |
| 9 | End Date | DT | O | 8 | ▶ |
| 10 | Next of Kin / Associated Parties Job Title | ST | O | 60 | ▶ |
| 11 | Next of Kin / Associated Parties Job Code/Class | JCC | O | 20 | ▶ |
| 12 | Next of Kin / Associated Parties Employee Number | CX | O | 250 | ▶ |
| 13 | Organization Name - NK1 | XON | O | 250 | ▶ |
| 14 | Marital Status | CE | O | 250 | ▶ |
| 15 | Administrative Sex | IS | O | 1 | ▶ |
| 16 | Date/Time of Birth | TS | O | 26 | ▶ |
| 17 | Living Dependency | IS | O | 2 | ▶ |
| 18 | Ambulatory Status | IS | O | 2 | ▶ |
| 19 | Citizenship | CE | O | 250 | ▶ |
| 20 | Primary Language | CE | O | 250 | ▶ |
| 21 | Living Arrangement | IS | O | 2 | ▶ |
| 22 | Publicity Code | CE | O | 250 | ▶ |
| 23 | Protection Indicator | ID | O | 1 | ▶ |
| 24 | Student Indicator | IS | O | 2 | ▶ |
| 25 | Religion | CE | O | 250 | ▶ |
| 26 | Mother's Maiden Name | XPN | O | 250 | ▶ |
| 27 | Nationality | CE | O | 250 | ▶ |
| 28 | Ethnic Group | CE | O | 250 | ▶ |
| 29 | Contact Reason | CE | O | 250 | ▶ |
| 30 | Contact Person's Name | XPN | O | 250 | ▶ |
| 31 | Contact Person's Telephone Number | XTN | O | 250 | ▶ |
| 32 | Contact Person's Address | XAD | O | 250 | ▶ |
| 33 | Next of Kin / Associated Party's Identifiers | CX | O | 250 | ▶ |
| 34 | Job Status | IS | O | 2 | ▶ |
| 35 | Race | CE | O | 250 | ▶ |
| 36 | Handicap | IS | O | 2 | ▶ |
| 37 | Contact Person Social Security Number | ST | O | 16 | ▶ |
| 38 | Next of Kin Birth Place | ST | O | 250 | ▶ |
| 39 | VIP Indicator | IS | O | 2 | ▶ |
Example Segment
1NK1||1|DOE^JANE^M|SPO^Spouse^HL70063|456 Oak St^^Chicago^IL^60601^USA|(312)555-9876|(312)555-4321|C^Emergency Contact^HL70131|20260101
Related Segments
Used In Message Types
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