This is the set of resources that conform to either of the profiles Extension - Tracking Number (http://hl7.org/fhir/us/mdi/StructureDefinition/Extension-tracking-number) and Tracking Number (http://hl7.org/fhir/us/mdi/StructureDefinition/Extension-tracking-number). E.g. what you have to deal with if you get resources conforming to one of them
| Name | Flags | Card. | Type | Description & Constraints Filter:   |
|---|---|---|---|---|
  Extension | 0..* | Tracking Numbers Extension | ||
  extension | 0..* | Extension | left: Additional content defined by implementations; right: Extension | |
 url | S | 1..1 | uri | identifies the meaning of the extension |
  value[x] | S | 0..1 | Identifier | Value of extension |
 extension | 0..* | Extension | Additional content defined by implementations | |
| use | ?!Σ | 0..1 | code | usual | official | temp | secondary | old (If known) Binding: ?? (required): Identifies the purpose for this identifier, if known . |
| type | SΣ | 0..1 | CodeableConcept | Tracking Number Type (extensible value set) Binding: ?? (extensible) |
| system | SΣ | 0..1 | uri | The namespace for the identifier value Example General: http://www.acme.com/identifiers/patient |
| value | SΣ | 0..1 | string | The value that is unique Example General: 123456 |
| 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 | ||||