{
  "resourceType": "CodeSystem",
  "status": "draft",
  "content": "not-present",
  "name": "OceanReferralTagCS",
  "id": "ocean-referral-tag",
  "title": "Ocean Referral Tag CodeSystem",
  "description": "Marks a resource as having entered Nexus EMR through the Ocean eReferral integration, and names the\nreferral it belongs to. Carried on `meta.tag`, where this is the tag's `system`.\n\n**A tag, not an identifier element.** The address identifies the `system` of a `Coding` in\n`meta.tag`, which is why it is declared as a code system even though its values are identifiers.\n\n**The system and the code answer different questions.** The presence of a tag under this system,\nwith the code ignored, is what says the resource came from the Ocean integration. The code says\nwhich referral: it is the Ocean eReferral reference taken from the referral's `ServiceRequest`, and\nevery resource persisted for that referral carries the same value, so `_tag=<system>|<referral>`\nretrieves the whole set -- the request, its communications, its attachments, and the organizations\nand practitioners that arrived with it.\n\n**Content is `not-present`, and it is not a fragment either.** The values are minted by Ocean, not\nby this specification, so there is no membership to publish. Treat each value as an opaque token,\nmatch it exactly, and do not parse it.\n\n**One older shape is still matched.** Some records carry the bundle entry's full URL in place of the\nreferral reference, and the matching path still searches for that form as a fallback. A store may\nhold both shapes under this one system, and neither can be derived from the other.\n\n**It is provenance, not status.** The tag says where the resource entered and what it belongs to. It\ncarries nothing about whether the referral is open, accepted or revoked, and its absence does not\nmean a resource was authored locally -- Ocean is one integration among several.\n\n**Nexus EMR writes this today at\n`http://services.well.com/fhir/tags/integration-provider/ocean` (FHIR-381)**: it is live in stored\n`meta.tag` codings and in code, and is under migration to the canonical declared here. Write the\ncanonical; expect both until the migration completes, and match both addresses exactly -- the two\nshare no final segment, so a suffix rule reaches neither reliably.",
  "url": "https://fhir.apps.health/CodeSystem/ocean-referral-tag",
  "experimental": false,
  "caseSensitive": true
}