^A31
ADT^A31 — Update Person Information
Sent to update person-level demographics in the Master Patient Index without visit context. It is the person-level equivalent of ADT^A08 (Update Patient Information) and is used when there is no active encounter.
When Is This Sent?
When a patient's demographic information changes — name, address, phone number, insurance — outside of a visit context. Common when the MPI receives a demographic correction from an external source such as a state registry or insurance verification service.
Real-World Usage
A31 is widely used in enterprise environments where the MPI maintains demographics separately from visit records. It ensures all connected systems have current demographics even for patients who have not had a recent encounter. Without A31, demographic corrections made to a patient's identity record in the MPI never reach downstream clinical systems.
Message Structure
Segment names link to their field-level reference pages.
| # | Segment | Purpose in this message | Req | Repeat |
|---|---|---|---|---|
| 1 | MSH | Message header with ADT^A31 in MSH.9 | R | — |
| 2 | EVN | Event type with A31 trigger | R | — |
| 3 | PID | Updated patient demographics | R | — |
| 4 | PD1 | Updated additional demographics including PCP | O | — |
| 5 | NK1 | Updated next of kin contacts | O | Yes |
| 6 | AL1 | Updated allergy information | O | Yes |
| 7 | IN1 | Updated insurance information | O | Yes |
Example Message
Realistic example with fake patient data. Paste into the HL7 Message Viewer to explore interactively.
1MSH||^~\&|ENTERPRISE_MPI|HEALTH_SYSTEM|MIRTH_PROD|EPIC|20260310110000||ADT^A31^ADT_A31|MSG00100|P|2.5.1 2EVN||A31|20260310110000 3PID||1||123456^^^HOSP_A^MR||Smith^John^Michael^^Mr.||19850315|M|||456 Updated Ave^^Springfield^IL^62706^US^H||2175557890^PRN^PH
Troubleshooting Scenarios
Demographic updates from MPI not reaching clinical systems
Cause
Clinical systems are subscribed only to A08 events (visit-level updates) and not A31 (person-level updates), so MPI-sourced corrections are never received.
Fix
Add A31 to the event subscription for all clinical systems that display patient demographics. Many systems can process A31 identically to A08 — both carry PID demographics without visit context. Verify with each system vendor.
Common Confusions
ADT^A31 (Update Person) vs ADT^A08 (Update Patient Info). A31 updates demographics at the person level — no PV1 visit context. A08 updates demographics in the context of an active visit and includes PV1. Use A31 for MPI-sourced corrections with no active visit; use A08 during an active encounter.
Related Message Types
Segment Reference
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