DG1 — Diagnosis
Appears in ADT, ORM, and DFT messages. Multiple DG1 segments may appear for multiple diagnoses.
The DG1 segment carries patient diagnosis information coded using ICD-9, ICD-10, or other diagnosis code systems. Multiple DG1 segments are used for patients with multiple diagnoses, including admitting, working, and final diagnoses.
Real-World Context
DG1 diagnoses are what drive DRG assignment and billing. The diagnosis type in DG1.6 (A=Admitting, W=Working, F=Final) matters as much as the code itself — payers use final diagnoses for claim adjudication, not working diagnoses. Missing principal diagnosis in the first DG1 is the most common cause of clean claim failures on inpatient claims.
Field Reference
Click any row to see the full description, common values, and troubleshooting tip.
| # | Field Name | Type | Req | Max Len | |
|---|---|---|---|---|---|
| 1 | Set ID - DG1 | SI | R | 4 | ▶ |
| 2 | Diagnosis Coding Method | ID | O | 2 | ▶ |
| 3 | Diagnosis Code - DG1 | CE | O | 250 | ▶ |
| 4 | Diagnosis Description | ST | O | 40 | ▶ |
| 5 | Diagnosis Date/Time | TS | O | 26 | ▶ |
| 6 | Diagnosis Type | IS | O | 2 | ▶ |
| 7 | Major Diagnostic Category | CE | O | 250 | ▶ |
| 8 | Diagnostic Related Group | CE | O | 250 | ▶ |
| 9 | DRG Approval Indicator | ID | O | 1 | ▶ |
| 10 | DRG Grouper Review Code | IS | O | 2 | ▶ |
| 11 | Outlier Type | CE | O | 250 | ▶ |
| 12 | Outlier Days | NM | O | 3 | ▶ |
| 13 | Outlier Cost | CP | O | 12 | ▶ |
| 14 | Grouper Version and Type | ST | O | 4 | ▶ |
| 15 | Diagnosis Priority | NM | O | 2 | ▶ |
| 16 | Diagnosing Clinician | XCN | O | 250 | ▶ |
| 17 | Diagnosis Classification | IS | O | 3 | ▶ |
| 18 | Confidential Indicator | ID | O | 1 | ▶ |
| 19 | Attestation Date/Time | TS | O | 26 | ▶ |
| 20 | Diagnosis Identifier | EI | O | 427 | ▶ |
| 21 | Diagnosis Action Code | ID | O | 1 | ▶ |
Example Segment
1DG1||1|I10|I21.0^ST-elevation MI involving LAD^ICD10|STEMI anterior|20260310143205|F||282^AMI with MCC|Y|||||||1|1234567890^JONES^ROBERT^^^MD^NPI|F|N|20260310200000
Related Segments
Used In Message Types
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