Current Build

{
  "resourceType" : "StructureDefinition",
  "id" : "DistanceFromLandmarkExt",
  "text" : {
    "status" : "generated",
    "div" : "<div xmlns=\"http://www.w3.org/1999/xhtml\"><table border=\"0\" cellpadding=\"0\" cellspacing=\"0\" style=\"border: 0px #F0F0F0 solid; font-size: 11px; font-family: verdana; vertical-align: top;\"><tr style=\"border: 1px #F0F0F0 solid; font-size: 11px; font-family: verdana; vertical-align: top;\"><th style=\"vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px\" class=\"hierarchy\"><a href=\"http://hl7.org/fhir/2017Jan/formats.html#table\" title=\"The logical name of the element\">Name</a></th><th style=\"vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px\" class=\"hierarchy\"><a href=\"http://hl7.org/fhir/2017Jan/formats.html#table\" title=\"Information about the use of the element\">Flags</a></th><th style=\"vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px\" class=\"hierarchy\"><a href=\"http://hl7.org/fhir/2017Jan/formats.html#table\" title=\"Minimum and Maximum # of times the the element can appear in the instance\">Card.</a></th><th style=\"width: 100px\" class=\"hierarchy\"><a href=\"http://hl7.org/fhir/2017Jan/formats.html#table\" title=\"Reference to the type of the element\">Type</a></th><th style=\"vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px\" class=\"hierarchy\"><a href=\"http://hl7.org/fhir/2017Jan/formats.html#table\" title=\"Additional information about the element\">Description &amp; Constraints</a><span style=\"float: right\"><a href=\"http://hl7.org/fhir/2017Jan/formats.html#table\" title=\"Legend for this format\"><img src=\"http://hl7.org/fhir/2017Jan/help16.png\" alt=\"doco\" style=\"background-color: inherit\"/></a></span></th></tr><tr style=\"border: 0px #F0F0F0 solid; padding:0px; vertical-align: top; background-color: white;\"><td style=\"vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px; white-space: nowrap; background-image: url(tbl_bck5.png)\" class=\"hierarchy\"><img src=\"tbl_spacer.png\" alt=\".\" style=\"background-color: inherit\" class=\"hierarchy\"/><img src=\"icon_element.gif\" alt=\".\" style=\"background-color: white; background-color: inherit\" title=\"Element\" class=\"hierarchy\"/> <span title=\"Slice DistanceFromLandmarkExt: The distance in cm a certain observation is made from a body landmark.\">Extension</span><a name=\"Extension\"> </a></td><td style=\"vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px\" class=\"hierarchy\"/><td style=\"vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px\" class=\"hierarchy\">0..1</td><td style=\"vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px\" class=\"hierarchy\"/><td style=\"vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px\" class=\"hierarchy\"/></tr>\r\n<tr style=\"border: 0px #F0F0F0 solid; padding:0px; vertical-align: top; background-color: white;\"><td style=\"vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px; white-space: nowrap; background-image: url(tbl_bck50.png)\" class=\"hierarchy\"><img src=\"tbl_spacer.png\" alt=\".\" style=\"background-color: inherit\" class=\"hierarchy\"/><img src=\"tbl_vjoin_slice.png\" alt=\".\" style=\"background-color: inherit\" class=\"hierarchy\"/><img src=\"icon_element.gif\" alt=\".\" style=\"background-color: white; background-color: inherit\" title=\"Element\" class=\"hierarchy\"/> <span title=\"null\">url</span><a name=\"Extension.url\"> </a></td><td style=\"vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px\" class=\"hierarchy\"/><td style=\"vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px\" class=\"hierarchy\"/><td style=\"vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px\" class=\"hierarchy\"/><td style=\"vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px\" class=\"hierarchy\"><span style=\"color: darkgreen\">&quot;http://hl7.org/fhir/hspc/StructureDefinition/DistanceFromLandmarkExt&quot;</span></td></tr>\r\n<tr style=\"border: 0px #F0F0F0 solid; padding:0px; vertical-align: top; background-color: white;\"><td style=\"vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px; white-space: nowrap; background-image: url(tbl_bck51.png)\" class=\"hierarchy\"><img src=\"tbl_spacer.png\" alt=\".\" style=\"background-color: inherit\" class=\"hierarchy\"/><img src=\"tbl_vjoin_slice.png\" alt=\".\" style=\"background-color: inherit\" class=\"hierarchy\"/><img src=\"icon_datatype.gif\" alt=\".\" style=\"background-color: white; background-color: inherit\" title=\"Data Type\" class=\"hierarchy\"/> <span title=\"null\">valueQuantity</span><a name=\"Extension.valueQuantity\"> </a></td><td style=\"vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px\" class=\"hierarchy\"/><td style=\"vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px\" class=\"hierarchy\"/><td style=\"vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px\" class=\"hierarchy\"><a href=\"http://hl7.org/fhir/2017Jan/datatypes.html#Quantity\" title=\"Quantity\">Quantity</a></td><td style=\"vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px\" class=\"hierarchy\"/></tr>\r\n<tr style=\"border: 0px #F0F0F0 solid; padding:0px; vertical-align: top; background-color: white;\"><td style=\"vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px; white-space: nowrap; background-image: url(tbl_bck510.png)\" class=\"hierarchy\"><img src=\"tbl_spacer.png\" alt=\".\" style=\"background-color: inherit\" class=\"hierarchy\"/><img src=\"tbl_vline_slice.png\" alt=\".\" style=\"background-color: inherit\" class=\"hierarchy\"/><img src=\"tbl_vjoin.png\" alt=\".\" style=\"background-color: inherit\" class=\"hierarchy\"/><img src=\"icon_primitive.png\" alt=\".\" style=\"background-color: white; background-color: inherit\" title=\"Primitive Data Type\" class=\"hierarchy\"/> <span title=\"null\">system</span><a name=\"Extension.valueQuantity.system\"> </a></td><td style=\"vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px\" class=\"hierarchy\"/><td style=\"vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px\" class=\"hierarchy\"/><td style=\"vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px\" class=\"hierarchy\"><a href=\"http://hl7.org/fhir/2017Jan/datatypes.html#uri\" title=\"uri\">uri</a></td><td style=\"vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px\" class=\"hierarchy\"><span style=\"font-weight:bold\">Fixed Value: </span><span style=\"color: darkgreen\">http://unitsofmeasure.org</span></td></tr>\r\n<tr style=\"border: 0px #F0F0F0 solid; padding:0px; vertical-align: top; background-color: white;\"><td style=\"vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px; white-space: nowrap; background-image: url(tbl_bck500.png)\" class=\"hierarchy\"><img src=\"tbl_spacer.png\" alt=\".\" style=\"background-color: inherit\" class=\"hierarchy\"/><img src=\"tbl_vline_slice.png\" alt=\".\" style=\"background-color: inherit\" class=\"hierarchy\"/><img src=\"tbl_vjoin_end.png\" alt=\".\" style=\"background-color: inherit\" class=\"hierarchy\"/><img src=\"icon_primitive.png\" alt=\".\" style=\"background-color: white; background-color: inherit\" title=\"Primitive Data Type\" class=\"hierarchy\"/> <span title=\"null\">code</span><a name=\"Extension.valueQuantity.code\"> </a></td><td style=\"vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px\" class=\"hierarchy\"/><td style=\"vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px\" class=\"hierarchy\"/><td style=\"vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px\" class=\"hierarchy\"><a href=\"http://hl7.org/fhir/2017Jan/datatypes.html#code\" title=\"code\">code</a></td><td style=\"vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px\" class=\"hierarchy\"><span style=\"font-weight:bold\">Fixed Value: </span><span style=\"color: darkgreen\">cm</span></td></tr>\r\n<tr style=\"border: 0px #F0F0F0 solid; padding:0px; vertical-align: top; background-color: white;\"><td style=\"vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px; white-space: nowrap; background-image: url(tbl_bck44.png)\" class=\"hierarchy\"><img src=\"tbl_spacer.png\" alt=\".\" style=\"background-color: inherit\" class=\"hierarchy\"/><img src=\"tbl_vjoin_end_slice.png\" alt=\".\" style=\"background-color: inherit\" class=\"hierarchy\"/><img src=\"icon_extension_simple.png\" alt=\".\" style=\"background-color: white; background-color: inherit\" title=\"Simple Extension\" class=\"hierarchy\"/> <span title=\"Extension URL = http://hl7.org/fhir/hspc/StructureDefinition/DeviceExt\">DeviceExt</span><a name=\"Extension.extension\"> </a></td><td style=\"vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px\" class=\"hierarchy\"/><td style=\"vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px\" class=\"hierarchy\">0..1</td><td style=\"vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px\" class=\"hierarchy\"><a href=\"http://hl7.org/fhir/2017Jan/datatypes.html#CodeableConcept\" title=\"CodeableConcept\">CodeableConcept</a></td><td style=\"vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px\" class=\"hierarchy\">Device<br/><span style=\"font-weight:bold\">URL: </span><a href=\"http://hl7.org/fhir/2017Jan/StructureDefinition-DeviceExt.html\">http://hl7.org/fhir/hspc/StructureDefinition/DeviceExt</a></td></tr>\r\n<tr><td colspan=\"5\" class=\"hierarchy\"><br/><a href=\"http://hl7.org/fhir/2017Jan/formats.html#table\" title=\"Legend for this format\"><img src=\"http://hl7.org/fhir/2017Jan/help16.png\" alt=\"doco\" style=\"background-color: inherit\"/> Documentation for this format</a></td></tr></table></div>"
  },
  "url" : "http://hl7.org/fhir/hspc/StructureDefinition/DistanceFromLandmarkExt",
  "version" : "2.0.0",
  "name" : "Distance From Landmark",
  "status" : "draft",
  "date" : "2019-03-08T00:00:00-06:00",
  "publisher" : "CIMI",
  "description" : "The distance in cm a certain observation is made from a body landmark.",
  "fhirVersion" : "3.0.1",
  "mapping" : [
    {
      "identity" : "rim",
      "uri" : "http://hl7.org/v3",
      "name" : "RIM Mapping"
    }
  ],
  "kind" : "complex-type",
  "abstract" : false,
  "contextType" : "resource",
  "context" : [
    "Observation",
    "Condition",
    "BodySite"
  ],
  "type" : "Extension",
  "baseDefinition" : "http://hl7.org/fhir/StructureDefinition/Extension",
  "derivation" : "constraint",
  "snapshot" : {
    "element" : [
      {
        "id" : "Extension",
        "path" : "Extension",
        "sliceName" : "DistanceFromLandmarkExt",
        "short" : "Extension",
        "definition" : "The distance in cm a certain observation is made from a body landmark.",
        "min" : 0,
        "max" : "1",
        "base" : {
          "path" : "Extension",
          "min" : 0,
          "max" : "*"
        },
        "condition" : [
          "ele-1"
        ],
        "constraint" : [
          {
            "key" : "ele-1",
            "severity" : "error",
            "human" : "All FHIR elements must have a @value or children",
            "expression" : "hasValue() | (children().count() > id.count())",
            "xpath" : "@value|f:*|h:div",
            "source" : "Element"
          },
          {
            "key" : "ext-1",
            "severity" : "error",
            "human" : "Must have either extensions or value[x], not both",
            "expression" : "extension.exists() != value.exists()",
            "xpath" : "exists(f:extension)!=exists(f:*[starts-with(local-name(.), 'value')])",
            "source" : "Extension"
          }
        ],
        "isModifier" : false
      },
      {
        "id" : "Extension.id",
        "path" : "Extension.id",
        "representation" : [
          "xmlAttr"
        ],
        "short" : "xml:id (or equivalent in JSON)",
        "definition" : "unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.",
        "min" : 0,
        "max" : "1",
        "base" : {
          "path" : "Element.id",
          "min" : 0,
          "max" : "1"
        },
        "type" : [
          {
            "code" : "string"
          }
        ],
        "mapping" : [
          {
            "identity" : "rim",
            "map" : "n/a"
          }
        ]
      },
      {
        "id" : "Extension.extension",
        "path" : "Extension.extension",
        "slicing" : {
          "discriminator" : [
            {
              "type" : "value",
              "path" : "url"
            }
          ],
          "description" : "Extensions are always sliced by (at least) url",
          "rules" : "open"
        },
        "short" : "Additional Content defined by implementations",
        "definition" : "May be used to represent additional information that is not part of the basic definition of the element. In order to make the use of extensions safe and manageable, there is a strict set of governance  applied to the definition and use of extensions. Though any implementer is allowed to define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.",
        "comment" : "There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions.  The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.",
        "alias" : [
          "extensions",
          "user content"
        ],
        "min" : 0,
        "max" : "*",
        "base" : {
          "path" : "Element.extension",
          "min" : 0,
          "max" : "*"
        },
        "type" : [
          {
            "code" : "Extension"
          }
        ],
        "mapping" : [
          {
            "identity" : "rim",
            "map" : "n/a"
          }
        ]
      },
      {
        "id" : "Extension.extension:Device",
        "path" : "Extension.extension",
        "sliceName" : "Device",
        "short" : "Device",
        "definition" : "An instrument, tool, analyzer, etc..",
        "min" : 0,
        "max" : "*",
        "base" : {
          "path" : "Element.extension",
          "min" : 0,
          "max" : "*"
        },
        "type" : [
          {
            "code" : "extension",
            "profile" : "http://hl7.org/fhir/hspc/StructureDefinition/DeviceExt"
          }
        ]
      },
      {
        "id" : "Extension.url",
        "path" : "Extension.url",
        "representation" : [
          "xmlAttr"
        ],
        "short" : "identifies the meaning of the extension",
        "definition" : "Source of the definition for the extension code - a logical name or a URL.",
        "comment" : "The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.",
        "min" : 1,
        "max" : "1",
        "base" : {
          "path" : "Extension.url",
          "min" : 1,
          "max" : "1"
        },
        "type" : [
          {
            "code" : "uri"
          }
        ],
        "fixedUri" : "http://hl7.org/fhir/hspc/StructureDefinition/DistanceFromLandmarkExt",
        "mapping" : [
          {
            "identity" : "rim",
            "map" : "N/A"
          }
        ]
      },
      {
        "id" : "Extension.valueQuantity",
        "path" : "Extension.valueQuantity",
        "short" : "A measured or measurable amount",
        "definition" : "A measured amount (or an amount that can potentially be measured). Note that measured amounts include amounts that are not precisely quantified, including amounts involving arbitrary units and floating currencies.",
        "comment" : "The context of use may frequently define what kind of quantity this is and therefore what kind of units can be used. The context of use may also restrict the values for the comparator.",
        "min" : 0,
        "max" : "1",
        "base" : {
          "path" : "Extension.value[x]",
          "min" : 0,
          "max" : "1"
        },
        "type" : [
          {
            "code" : "Quantity",
            "profile" : "http://hl7.org/fhir/StructureDefinition/Quantity"
          }
        ],
        "condition" : [
          "ele-1"
        ],
        "constraint" : [
          {
            "key" : "ele-1",
            "severity" : "error",
            "human" : "All FHIR elements must have a @value or children",
            "expression" : "hasValue() | (children().count() > id.count())",
            "xpath" : "@value|f:*|h:div",
            "source" : "Element"
          },
          {
            "key" : "qty-3",
            "severity" : "error",
            "human" : "If a code for the unit is present, the system SHALL also be present",
            "expression" : "code.empty() or system.exists()",
            "xpath" : "not(exists(f:code)) or exists(f:system)",
            "source" : "Quantity"
          }
        ],
        "mapping" : [
          {
            "identity" : "rim",
            "map" : "n/a"
          },
          {
            "identity" : "v2",
            "map" : "SN (see also Range) or CQ"
          },
          {
            "identity" : "rim",
            "map" : "PQ, IVL<PQ>, MO, CO, depending on the values"
          }
        ]
      },
      {
        "id" : "Extension.valueQuantity.id",
        "path" : "Extension.valueQuantity.id",
        "representation" : [
          "xmlAttr"
        ],
        "short" : "xml:id (or equivalent in JSON)",
        "definition" : "unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.",
        "min" : 0,
        "max" : "1",
        "base" : {
          "path" : "Element.id",
          "min" : 0,
          "max" : "1"
        },
        "type" : [
          {
            "code" : "string"
          }
        ],
        "mapping" : [
          {
            "identity" : "rim",
            "map" : "n/a"
          }
        ]
      },
      {
        "id" : "Extension.valueQuantity.extension",
        "path" : "Extension.valueQuantity.extension",
        "slicing" : {
          "discriminator" : [
            {
              "type" : "value",
              "path" : "url"
            }
          ],
          "description" : "Extensions are always sliced by (at least) url",
          "rules" : "open"
        },
        "short" : "Additional Content defined by implementations",
        "definition" : "May be used to represent additional information that is not part of the basic definition of the element. In order to make the use of extensions safe and manageable, there is a strict set of governance  applied to the definition and use of extensions. Though any implementer is allowed to define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.",
        "comment" : "There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions.  The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.",
        "alias" : [
          "extensions",
          "user content"
        ],
        "min" : 0,
        "max" : "*",
        "base" : {
          "path" : "Element.extension",
          "min" : 0,
          "max" : "*"
        },
        "type" : [
          {
            "code" : "Extension"
          }
        ],
        "mapping" : [
          {
            "identity" : "rim",
            "map" : "n/a"
          }
        ]
      },
      {
        "id" : "Extension.valueQuantity.value",
        "path" : "Extension.valueQuantity.value",
        "short" : "Numerical value (with implicit precision)",
        "definition" : "The value of the measured amount. The value includes an implicit precision in the presentation of the value.",
        "comment" : "The implicit precision in the value should always be honored. Monetary values have their own rules for handling precision (refer to standard accounting text books).",
        "requirements" : "Precision is handled implicitly in almost all cases of measurement.",
        "min" : 0,
        "max" : "1",
        "base" : {
          "path" : "Quantity.value",
          "min" : 0,
          "max" : "1"
        },
        "type" : [
          {
            "code" : "decimal"
          }
        ],
        "isSummary" : true,
        "mapping" : [
          {
            "identity" : "v2",
            "map" : "SN.2  / CQ - N/A"
          },
          {
            "identity" : "rim",
            "map" : "PQ.value, CO.value, MO.value, IVL.high or IVL.low depending on the value"
          }
        ]
      },
      {
        "id" : "Extension.valueQuantity.comparator",
        "path" : "Extension.valueQuantity.comparator",
        "short" : "< | <= | >= | > - how to understand the value",
        "definition" : "How the value should be understood and represented - whether the actual value is greater or less than the stated value due to measurement issues; e.g. if the comparator is \"<\" , then the real value is < stated value.",
        "comment" : "This is labeled as \"Is Modifier\" because the comparator modifies the interpretation of the value significantly. If there is no comparator, then there is no modification of the value.",
        "requirements" : "Need a framework for handling measures where the value is <5ug/L or >400mg/L due to the limitations of measuring methodology.",
        "min" : 0,
        "max" : "1",
        "base" : {
          "path" : "Quantity.comparator",
          "min" : 0,
          "max" : "1"
        },
        "type" : [
          {
            "code" : "code"
          }
        ],
        "meaningWhenMissing" : "If there is no comparator, then there is no modification of the value",
        "isModifier" : true,
        "isSummary" : true,
        "binding" : {
          "extension" : [
            {
              "url" : "http://hl7.org/fhir/StructureDefinition/elementdefinition-bindingName",
              "valueString" : "QuantityComparator"
            }
          ],
          "strength" : "required",
          "description" : "How the Quantity should be understood and represented.",
          "valueSetReference" : {
            "reference" : "http://hl7.org/fhir/ValueSet/quantity-comparator"
          }
        },
        "mapping" : [
          {
            "identity" : "v2",
            "map" : "SN.1  / CQ.1"
          },
          {
            "identity" : "rim",
            "map" : "IVL properties"
          }
        ]
      },
      {
        "id" : "Extension.valueQuantity.unit",
        "extension" : [
          {
            "url" : "http://hl7.org/fhir/StructureDefinition/elementdefinition-translatable",
            "valueBoolean" : true
          }
        ],
        "path" : "Extension.valueQuantity.unit",
        "short" : "Unit representation",
        "definition" : "A human-readable form of the unit.",
        "requirements" : "There are many representations for units of measure and in many contexts, particular representations are fixed and required. I.e. mcg for micrograms.",
        "min" : 0,
        "max" : "1",
        "base" : {
          "path" : "Quantity.unit",
          "min" : 0,
          "max" : "1"
        },
        "type" : [
          {
            "code" : "string"
          }
        ],
        "isSummary" : true,
        "mapping" : [
          {
            "identity" : "v2",
            "map" : "(see OBX.6 etc.) / CQ.2"
          },
          {
            "identity" : "rim",
            "map" : "PQ.unit"
          }
        ]
      },
      {
        "id" : "Extension.valueQuantity.system",
        "path" : "Extension.valueQuantity.system",
        "short" : "Primitive Type uri",
        "definition" : "String of characters used to identify a name or a resource",
        "comment" : "see http://en.wikipedia.org/wiki/Uniform_resource_identifier",
        "requirements" : "Need to know the system that defines the coded form of the unit.",
        "min" : 0,
        "max" : "1",
        "base" : {
          "path" : "Quantity.system",
          "min" : 0,
          "max" : "1"
        },
        "type" : [
          {
            "code" : "uri",
            "profile" : "http://hl7.org/fhir/StructureDefinition/uri"
          }
        ],
        "fixedUri" : "http://unitsofmeasure.org",
        "constraint" : [
          {
            "key" : "ele-1",
            "severity" : "error",
            "human" : "All FHIR elements must have a @value or children",
            "expression" : "hasValue() | (children().count() > id.count())",
            "xpath" : "@value|f:*|h:div",
            "source" : "Element"
          }
        ],
        "mustSupport" : false
      },
      {
        "id" : "Extension.valueQuantity.code",
        "path" : "Extension.valueQuantity.code",
        "short" : "Primitive Type code",
        "definition" : "A string which has at least one character and no leading or trailing whitespace and where there is no whitespace other than single spaces in the contents",
        "comment" : "The preferred system is UCUM, but SNOMED CT can also be used (for customary units) or ISO 4217 for currency.  The context of use may additionally require a code from a particular system.",
        "requirements" : "Need a computable form of the unit that is fixed across all forms. UCUM provides this for quantities, but SNOMED CT provides many units of interest.",
        "min" : 0,
        "max" : "1",
        "base" : {
          "path" : "Quantity.code",
          "min" : 0,
          "max" : "1"
        },
        "type" : [
          {
            "code" : "code",
            "profile" : "http://hl7.org/fhir/StructureDefinition/code"
          }
        ],
        "fixedCode" : "cm",
        "constraint" : [
          {
            "key" : "ele-1",
            "severity" : "error",
            "human" : "All FHIR elements must have a @value or children",
            "expression" : "hasValue() | (children().count() > id.count())",
            "xpath" : "@value|f:*|h:div",
            "source" : "Element"
          }
        ],
        "mustSupport" : false
      }
    ]
  },
  "differential" : {
    "element" : [
      {
        "id" : "Extension",
        "path" : "Extension",
        "sliceName" : "DistanceFromLandmarkExt",
        "definition" : "The distance in cm a certain observation is made from a body landmark.",
        "min" : 0,
        "max" : "1",
        "isModifier" : false
      },
      {
        "id" : "Extension.extension:Device",
        "path" : "Extension.extension",
        "sliceName" : "Device",
        "short" : "Device",
        "type" : [
          {
            "code" : "extension",
            "profile" : "http://hl7.org/fhir/hspc/StructureDefinition/DeviceExt"
          }
        ]
      },
      {
        "id" : "Extension.url",
        "path" : "Extension.url",
        "fixedUri" : "http://hl7.org/fhir/hspc/StructureDefinition/DistanceFromLandmarkExt"
      },
      {
        "id" : "Extension.valueQuantity",
        "path" : "Extension.valueQuantity",
        "type" : [
          {
            "code" : "Quantity",
            "profile" : "http://hl7.org/fhir/StructureDefinition/Quantity"
          }
        ]
      },
      {
        "id" : "Extension.valueQuantity.system",
        "path" : "Extension.valueQuantity.system",
        "type" : [
          {
            "code" : "uri",
            "profile" : "http://hl7.org/fhir/StructureDefinition/uri"
          }
        ],
        "fixedUri" : "http://unitsofmeasure.org",
        "mustSupport" : false,
        "isModifier" : false
      },
      {
        "id" : "Extension.valueQuantity.code",
        "path" : "Extension.valueQuantity.code",
        "type" : [
          {
            "code" : "code",
            "profile" : "http://hl7.org/fhir/StructureDefinition/code"
          }
        ],
        "fixedCode" : "cm",
        "mustSupport" : false,
        "isModifier" : false
      }
    ]
  }
}