Last updated: 2024-04-24 00:00:00+0000
This case-sensitive code system http://terminology.hl7.org/CodeSystem/history-absent-reason defines the following codes:
| Code | Display | Definition |
| subject-unknown | Subject Unknown | Patient does not know the subject, e.g. the biological parent of an adopted patient. |
| withheld | Information Withheld | The patient withheld or refused to share the information. |
| unable-to-obtain | Unable To Obtain | Information cannot be obtained; e.g. unconscious patient. |
| deferred | Deferred | Patient does not have the information now, but can provide the information at a later date. |