{
  "resourceType": "CodeSystem",
  "status": "draft",
  "content": "complete",
  "name": "ReportingProjectionCS",
  "id": "reporting-projection",
  "title": "Reporting Projection Marker CodeSystem",
  "description": "Markers the reporting projection mints for itself, held under a system no source value set uses so\nthat a minted marker is never mistaken for an answer the chart captured.\n\n**Why they exist.** Reporting flattens a patient's chart into one row per patient, and some chart\nelements repeat. Collapsing a repeating element by taking whichever answer was listed first is not a\nsimplification but a wrong value: it attributes the patient to a single answer they did not give\nalone, in the dimension being measured. The row carries a marker instead, and the report counts the\nmarker as its own visible segment.\n\n**Read the system, not the code.** A projection column carries a (system, code) pair, and most codes\nin it came from the value set the chart recorded -- including the absence answers (v3 NullFlavor\n`OTH`, data-absent-reason `asked-declined`, `asked-unknown`), which are captured answers rather than\nmissing data and keep counting as answers. The dedicated system is what lets a consumer tell a\nminted marker from a recorded one by inspection, without consulting a list of source systems.\n\n**These are not values on a FHIR element.** Unlike the other code systems this guide declares,\nvalues under this one are written into the projection's own row rather than onto a resource. It is\ndeclared because it shares a column with codes that did come from FHIR, and a consumer has to tell\nthe two apart.\n\n**One marker today, and the vocabulary is expected to grow** as more repeating elements reach the\nprojection. Declaring the system rather than waiting for a second marker is what lets the \"is this\nminted\" test be written once, against the system, rather than against a growing list of literals.\n\n**`multiple` is not an answer.** It records that the patient's answers are not one value. Folding it\ninto an \"other\" bucket, or dropping it, undercounts exactly the patients it exists to make visible.\n\n**MIGRATION.** Nexus EMR writes this system today as\n`http://services.well.com/fhir/CodeSystem/reporting-projection`, an address this specification does\nnot publish, on a host it does not govern. It is live in code and in stored projection rows, and is\nunder migration to the canonical declared here. Write the canonical; expect both until the migration\ncompletes, and match both addresses exactly rather than deriving one from the other.",
  "url": "https://fhir.apps.health/CodeSystem/reporting-projection",
  "concept": [
    {
      "code": "multiple",
      "display": "More than one answer",
      "definition": "The patient gave MORE THAN ONE answer for an element the projection can hold only one of, so the row records that fact rather than choosing between them. Written today where a patient self-identified with more than one racialized group. It is not itself one of the answers and must not be tallied as one, nor folded into an 'other' bucket: a report that does either undercounts every patient the marker was minted for."
    }
  ],
  "experimental": false,
  "caseSensitive": true,
  "count": 1
}