# Null Reasons

Whenever submitting data to SanteDB's CDR where an element is marked as required, you may submit a null reason (also known as a null flavor). The allowed null flavors are:U

| Mnemonic           | Description                                                                                                                                       |
| ------------------ | ------------------------------------------------------------------------------------------------------------------------------------------------- |
| AskedUnknown       | The value was asked for, however the known value could not be collected.                                                                          |
| Derived            | The value was not supplied because it can be calculated from other data provided.                                                                 |
| Invalid            | The value was not supplied because the known value would violate business rules.                                                                  |
| Masked             | The value is not supplied because the value is sensitive and disclosure may violate privacy.                                                      |
| NotApplicable      | The value is not supplied because it is not applicable (for example: Last menstrual period for a man)                                             |
| NotAsked           | The value is not supplied because it was not asked for.                                                                                           |
| Unavailable        | The value is not available at the time of data capture.                                                                                           |
| NoInformation      | The value is not supplied because there is no information supplied. This is the default null flavor to use.                                       |
| NegativeInfinity   | The value is not supplied because it is negative infinity.                                                                                        |
| Other              | The value was not supplied for some other reason.                                                                                                 |
| PositiveInfinity   | The value was not supplied because it is positive infinity.                                                                                       |
| SufficientQuantity | The value is of sufficient quantity to meet a clinical trigger, however the exact value could not be measured (i.e. off-scale 0 or off-scale max) |
| Trace              | The value is above 0, however the exact value is unknown or the equipment could not measure the quantity.                                         |
| UnEncoded          | The value could not be encoded into the message.                                                                                                  |
| Unknown            | The value is unknown (not asked, not measured, etc.)                                                                                              |
