{
  "resourceType": "StructureDefinition",
  "id": "observation-value-quantity",
  "url": "http://vha.gov/fhir/StructureDefinition/observation-value-quantity",
  "name": "observation-value-quantity",
  "status": "draft",
  "fhirVersion": "3.0.1",
  "kind": "complex-type",
  "abstract": false,
  "type": "Quantity",
  "baseDefinition": "http://hl7.org/fhir/StructureDefinition/Quantity",
  "derivation": "constraint",
  "differential": {
    "element": [
      {
        "id": "Quantity",
        "path": "Quantity",
        "short": "A measured or measurable amount, with UCUM units of measure required",
        "definition": "A measured amount (or an amount that can potentially be measured) used as the value of an observation that is encoded using the observation-va profile (http://vha.gov/fhir/StructureDefinition/observation-va).  This profiled data type requires the use of UCUM codes as the unit of measure"
      },
      {
        "id": "Quantity.system",
        "path": "Quantity.system",
        "short": "UCUM",
        "definition": "UCUM codes",
        "min": 1,
        "fixedUri": "http://unitsofmeasure.org"
      }
    ]
  }
}