The patient's principal diagnosis should be recorded in form locator 67 of the UB-04 form. Other or secondary diagnoses, complications and comorbidities should be listed in form locators 67 A-Q. The admitting diagnosis (if different from the principal diagnosis) should be listed in form locator 69.
Example of Selecting a Diagnosis Code
A patient is admitted with chest pain. After testing, he is diagnosed with myocardial infarction (MI). He has a history of chronic obstructive pulmonary disease (COPD). While hospitalized, the patient suffers respiratory failure. The claim would be coded as follows:
| Diagnosis Type | Form Locator | Description | ICD‑9‑CM Code | ICD‑10‑CM Code |
|---|---|---|---|---|
| Principal diagnosis | 67 | Anterior wall MI | 410.11 | I21.01 I21.02 I21.09 I22.0 |
| Secondary diagnosis complication | 67A | Respiratory failure | 799.1 | R09.2 |
| Admitting diagnosis | 69 | Chest pain | 786.50 | R07.9 |
Note: COPD is a historical comorbidity and cannot be designated as a secondary diagnosis in this example.
Specificity
All diagnoses should be coded to the ultimate specificity. Do not use a three-digit diagnosis code if a more specific four-, five-, six- or seven-digit diagnosis code is available. Coding a nonspecific diagnosis may delay the processing of the claim.
Revision History
| Date | Nature of Revision |
|---|---|
| 08/03/2026 | Migrated to new platform |