| Name | Flags | Card. | Type | Description & Constraints |
|---|---|---|---|---|
  Identifier | ΣN | Element | An identifier intended for computation + Warning: Identifier with no value has limited utility. If communicating that an identifier value has been suppressed or missing, the value element SHOULD be present with an extension indicating the missing semantic - e.g. data-absent-reason Elements defined in Ancestors: id, extension | |
  use | ?!Σ | 0..1 | code | usual | official | temp | secondary | old (If known) Binding: IdentifierUse (Required) |
 type | Σ | 0..1 | CodeableConcept | Description of identifier Binding: Identifier Type Codes (Extensible) |
| system | Σ | 0..1 | uri | The namespace for the identifier value |
| value | ΣC | 0..1 | string | The value that is unique |
| period | Σ | 0..1 | Period | Time period when id is/was valid for use |
  assigner | Σ | 0..1 | Reference(Organization) | Organization that issued id (may be just text) |
| Documentation for this format | ||||