Duration.profile.xml

StructureDefinition for Duration

<StructureDefinition xmlns="http://hl7.org/fhir">
  <id value="Duration"/>
  <text>
    <status value="generated"/>
    <div xmlns="http://www.w3.org/1999/xhtml">
      <h2>Data type Duration</h2>
      <p>A length of time</p>
      <h3>Rule</h3>
      <p>There SHALL be a code if there is a value and it SHALL be an expression of time.  If system
         is present, it SHALL be UCUM.</p>
      <p>XPath:</p>
      <blockquote>
        <pre>(f:code or not(f:value)) and (not(exists(f:system)) or f:system/@value='http://unitsofmeasure.org')</pre>
      </blockquote>
    </div>
  </text>
  <url value="http://hl7.org/fhir/StructureDefinition/Duration"/>
  <name value="Duration"/>
  <status value="draft"/>
  <publisher value="HL7 FHIR Standard"/>
  <contact>
    <telecom>
      <system value="other"/>
      <value value="http://hl7.org/fhir"/>
    </telecom>
  </contact>
  <date value="2015-12-11T17:38:40+11:00"/>
  <description value="A length of time"/>
  <fhirVersion value="1.2.0"/>
  <kind value="datatype"/>
  <constrainedType value="Quantity"/>
  <abstract value="false"/>
  <base value="http://hl7.org/fhir/StructureDefinition/Quantity"/>
  <snapshot>
    <element>
      <path value="Quantity"/>
      <name value="Duration"/>
      <short value="A length of time"/>
      <definition value="There SHALL be a code if there is a value and it SHALL be an expression of time.  If system
       is present, it SHALL be UCUM."/>
      <comments value="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 value="0"/>
      <max value="*"/>
      <base>
        <path value="Quantity"/>
        <min value="0"/>
        <max value="*"/>
      </base>
      <type>
        <code value="Quantity"/>
      </type>
      <constraint>
        <extension url="http://hl7.org/fhir/StructureDefinition/structuredefinition-expression">
          <valueString value="code.empty() or system"/>
        </extension>
        <key value="qty-3"/>
        <severity value="error"/>
        <human value="If a code for the unit is present, the system SHALL also be present"/>
        <xpath value="not(exists(f:code)) or exists(f:system)"/>
      </constraint>
      <constraint>
        <extension url="http://hl7.org/fhir/StructureDefinition/structuredefinition-expression">
          <valueString value="(code or value.empty()) and (system.empty() or system = %ucum)"/>
        </extension>
        <key value="drt-1"/>
        <severity value="error"/>
        <human value="There SHALL be a code if there is a value and it SHALL be an expression of time.  If system
         is present, it SHALL be UCUM."/>
        <xpath value="(f:code or not(f:value)) and (not(exists(f:system)) or f:system/@value='http://unitsofmeasure.org')"/>
      </constraint>
      <isSummary value="true"/>
      <mapping>
        <identity value="v2"/>
        <map value="SN (see also Range) or CQ"/>
      </mapping>
      <mapping>
        <identity value="rim"/>
        <map value="PQ, IVL&lt;PQ&gt;, MO, CO, depending on the values"/>
      </mapping>
    </element>
    <element>
      <path value="Quantity.id"/>
      <representation value="xmlAttr"/>
      <short value="xml:id (or equivalent in JSON)"/>
      <definition value="unique id for the element within a resource (for internal references)."/>
      <min value="0"/>
      <max value="1"/>
      <base>
        <path value="Quantity.id"/>
        <min value="0"/>
        <max value="1"/>
      </base>
      <type>
        <code value="id"/>
      </type>
      <mapping>
        <identity value="rim"/>
        <map value="n/a"/>
      </mapping>
    </element>
    <element>
      <path value="Quantity.extension"/>
      <short value="Additional Content defined by implementations"/>
      <definition value="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."/>
      <comments value="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 value="extensions"/>
      <alias value="user content"/>
      <min value="0"/>
      <max value="*"/>
      <base>
        <path value="Quantity.extension"/>
        <min value="0"/>
        <max value="*"/>
      </base>
      <type>
        <code value="Extension"/>
      </type>
      <mapping>
        <identity value="rim"/>
        <map value="n/a"/>
      </mapping>
    </element>
    <element>
      <path value="Quantity.value"/>
      <short value="Numerical value (with implicit precision)"/>
      <definition value="The value of the measured amount. The value includes an implicit precision in the presentation
       of the value."/>
      <comments value="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 value="Precision is handled implicitly in almost all cases of measurement."/>
      <min value="0"/>
      <max value="1"/>
      <base>
        <path value="Quantity.value"/>
        <min value="0"/>
        <max value="1"/>
      </base>
      <type>
        <code value="decimal"/>
      </type>
      <isSummary value="true"/>
      <mapping>
        <identity value="v2"/>
        <map value="SN.2  / CQ - N/A"/>
      </mapping>
      <mapping>
        <identity value="rim"/>
        <map value="PQ.value, CO.value, MO.value, IVL.high or IVL.low depending on the value"/>
      </mapping>
    </element>
    <element>
      <path value="Quantity.comparator"/>
      <short value="&lt; | &lt;= | &gt;= | &gt; - how to understand the value"/>
      <definition value="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 &quot;&lt;&quot;
       , then the real value is &lt; stated value."/>
      <comments value="This is labeled as &quot;Is Modifier&quot; because the comparator modifies the interpretation
       of the value significantly. If there is no comparator, then there is no modification of
       the value."/>
      <requirements value="Need a framework for handling measures where the value is &lt;5ug/L or &gt;400mg/L due
       to the limitations of measuring methodology."/>
      <min value="0"/>
      <max value="1"/>
      <base>
        <path value="Quantity.comparator"/>
        <min value="0"/>
        <max value="1"/>
      </base>
      <type>
        <code value="code"/>
      </type>
      <meaningWhenMissing value="If there is no comparator, then there is no modification of the value"/>
      <isModifier value="true"/>
      <isSummary value="true"/>
      <binding>
        <strength value="required"/>
        <description value="How the Quantity should be understood and represented."/>
        <valueSetReference>
          <reference value="http://hl7.org/fhir/ValueSet/quantity-comparator"/>
        </valueSetReference>
      </binding>
      <mapping>
        <identity value="v2"/>
        <map value="SN.1  / CQ.1"/>
      </mapping>
      <mapping>
        <identity value="rim"/>
        <map value="IVL properties"/>
      </mapping>
    </element>
    <element>
      <path value="Quantity.unit"/>
      <short value="Unit representation"/>
      <definition value="A human-readable form of the unit."/>
      <requirements value="There are many representations for units of measure and in many contexts, particular representations
       are fixed and required. I.e. mcg for micrograms."/>
      <min value="0"/>
      <max value="1"/>
      <base>
        <path value="Quantity.unit"/>
        <min value="0"/>
        <max value="1"/>
      </base>
      <type>
        <code value="string"/>
      </type>
      <isSummary value="true"/>
      <mapping>
        <identity value="v2"/>
        <map value="(see OBX.6 etc.) / CQ.2"/>
      </mapping>
      <mapping>
        <identity value="rim"/>
        <map value="PQ.unit"/>
      </mapping>
    </element>
    <element>
      <path value="Quantity.system"/>
      <short value="System that defines coded unit form"/>
      <definition value="The identification of the system that provides the coded form of the unit."/>
      <requirements value="Need to know the system that defines the coded form of the unit."/>
      <min value="0"/>
      <max value="1"/>
      <base>
        <path value="Quantity.system"/>
        <min value="0"/>
        <max value="1"/>
      </base>
      <type>
        <code value="uri"/>
      </type>
      <condition value="qty-3"/>
      <isSummary value="true"/>
      <mapping>
        <identity value="v2"/>
        <map value="(see OBX.6 etc.) / CQ.2"/>
      </mapping>
      <mapping>
        <identity value="rim"/>
        <map value="CO.codeSystem, PQ.translation.codeSystem"/>
      </mapping>
    </element>
    <element>
      <path value="Quantity.code"/>
      <short value="Coded form of the unit"/>
      <definition value="A computer processable form of the unit in some unit representation system."/>
      <comments value="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 value="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 value="0"/>
      <max value="1"/>
      <base>
        <path value="Quantity.code"/>
        <min value="0"/>
        <max value="1"/>
      </base>
      <type>
        <code value="code"/>
      </type>
      <isSummary value="true"/>
      <mapping>
        <identity value="v2"/>
        <map value="(see OBX.6 etc.) / CQ.2"/>
      </mapping>
      <mapping>
        <identity value="rim"/>
        <map value="PQ.code, MO.currency, PQ.translation.code"/>
      </mapping>
    </element>
  </snapshot>
  <differential>
    <element>
      <path value="Quantity"/>
      <name value="Duration"/>
      <short value="A length of time"/>
      <definition value="There SHALL be a code if there is a value and it SHALL be an expression of time.  If system
       is present, it SHALL be UCUM."/>
      <min value="0"/>
      <max value="*"/>
      <type>
        <code value="Quantity"/>
      </type>
      <constraint>
        <extension url="http://hl7.org/fhir/StructureDefinition/structuredefinition-expression">
          <valueString value="(code or value.empty()) and (system.empty() or system = %ucum)"/>
        </extension>
        <key value="drt-1"/>
        <severity value="error"/>
        <human value="There SHALL be a code if there is a value and it SHALL be an expression of time.  If system
         is present, it SHALL be UCUM."/>
        <xpath value="(f:code or not(f:value)) and (not(exists(f:system)) or f:system/@value='http://unitsofmeasure.org')"/>
      </constraint>
      <isModifier value="false"/>
    </element>
  </differential>
</StructureDefinition>