Release 4

This page is part of the FHIR Specification (v4.0.1: R4 - Mixed Normative and STU) in it's permanent home (it will always be available at this URL). The current version which supercedes this version is 5.0.0. For a full list of available versions, see the Directory of published versions . Page versions: R5 R4B R4 R3

StructureDefinition: ShareableCodeSystem - XML

Vocabulary Work Group Maturity Level: 2Trial UseUse Context: Any

ShareableCodeSystem

<?xml version="1.0" encoding="UTF-8"?>

<StructureDefinition xmlns="http://hl7.org/fhir">
  <id value="shareablecodesystem"/> 
  <text> 
    <status value="generated"/> 
    <div xmlns="http://www.w3.org/1999/xhtml">to do</div> 
  </text> 
  <extension url="http://hl7.org/fhir/StructureDefinition/structuredefinition-fmm">
    <valueInteger value="5"/> 
  </extension> 
  <extension url="http://hl7.org/fhir/StructureDefinition/structuredefinition-wg">
    <valueCode value="vocab"/> 
  </extension> 
  <extension url="http://hl7.org/fhir/StructureDefinition/structuredefinition-standards-status">
    <valueCode value="trial-use"/> 
  </extension> 
  <url value="http://hl7.org/fhir/StructureDefinition/shareablecodesystem"/> 
  <version value="4.0.1"/> 
  <name value="Shareable CodeSystem"/> 
  <status value="draft"/> 
  <experimental value="false"/> 
  <date value="2019-11-01T09:29:23+11:00"/> 
  <publisher value="HL7"/> 
  <description value="Enforces the minimum information set for the value set metadata required by HL7 and other
   organizations that share and publish value sets"/> 
  <fhirVersion value="4.0.1"/> 
  <mapping> 
    <identity value="rim"/> 
    <uri value="http://hl7.org/v3"/> 
    <name value="RIM Mapping"/> 
  </mapping> 
  <mapping> 
    <identity value="workflow"/> 
    <uri value="http://hl7.org/fhir/workflow"/> 
    <name value="Workflow Pattern"/> 
  </mapping> 
  <mapping> 
    <identity value="w5"/> 
    <uri value="http://hl7.org/fhir/fivews"/> 
    <name value="FiveWs Pattern Mapping"/> 
  </mapping> 
  <mapping> 
    <identity value="objimpl"/> 
    <uri value="http://hl7.org/fhir/object-implementation"/> 
    <name value="Object Implementation Information"/> 
  </mapping> 
  <kind value="resource"/> 
  <abstract value="false"/> 
  <type value="CodeSystem"/> 
  <baseDefinition value="http://hl7.org/fhir/StructureDefinition/CodeSystem"/> 
  <derivation value="constraint"/> 
  <snapshot> 
    <element id="CodeSystem">
      <path value="CodeSystem"/> 
      <short value="Declares the existence of and describes a code system or code system supplement"/> 
      <definition value="The CodeSystem resource is used to declare the existence of and describe a code system
       or code system supplement and its key properties, and optionally define a part or all
       of its content."/> 
      <min value="1"/> 
      <max value="1"/> 
      <base> 
        <path value="CodeSystem"/> 
        <min value="0"/> 
        <max value="*"/> 
      </base> 
      <constraint> 
        <key value="csd-0"/> 
        <severity value="warning"/> 
        <human value="Name should be usable as an identifier for the module by machine processing applications
         such as code generation"/> 
        <expression value="name.matches('[A-Z]([A-Za-z0-9_]){0,254}')"/> 
        <xpath value="not(exists(f:name/@value)) or matches(f:name/@value, '[A-Z]([A-Za-z0-9_]){0,254}')"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/CodeSystem"/> 
      </constraint> 
      <constraint> 
        <key value="csd-1"/> 
        <severity value="error"/> 
        <human value="Within a code system definition, all the codes SHALL be unique"/> 
        <expression value="concept.code.combine($this.descendants().concept.code).isDistinct()"/> 
        <xpath value="count(distinct-values(descendant::f:concept/f:code/@value))=count(descendant::f:concept)"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/CodeSystem"/> 
      </constraint> 
      <constraint> 
        <key value="dom-2"/> 
        <severity value="error"/> 
        <human value="If the resource is contained in another resource, it SHALL NOT contain nested Resources"/> 
        <expression value="contained.contained.empty()"/> 
        <xpath value="not(parent::f:contained and f:contained)"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/DomainResource"/> 
      </constraint> 
      <constraint> 
        <key value="dom-3"/> 
        <severity value="error"/> 
        <human value="If the resource is contained in another resource, it SHALL be referred to from elsewhere
         in the resource or SHALL refer to the containing resource"/> 
        <expression value="contained.where((('#'+id in (%resource.descendants().reference | %resource.descendants().as(canonica
        l) | %resource.descendants().as(uri) | %resource.descendants().as(url))) or descendants().where(refer
        ence = '#').exists() or descendants().where(as(canonical) = '#').exists() or descendants().where(as(c
        anonical) = '#').exists()).not()).trace('unmatched', id).empty()"/> 
        <xpath value="not(exists(for $id in f:contained/*/f:id/@value return $contained[not(parent::*/descendant::f:refere
        nce/@value=concat('#', $contained/*/id/@value) or descendant::f:reference[@value='#'])]))"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/DomainResource"/> 
      </constraint> 
      <constraint> 
        <key value="dom-4"/> 
        <severity value="error"/> 
        <human value="If a resource is contained in another resource, it SHALL NOT have a meta.versionId or
         a meta.lastUpdated"/> 
        <expression value="contained.meta.versionId.empty() and contained.meta.lastUpdated.empty()"/> 
        <xpath value="not(exists(f:contained/*/f:meta/f:versionId)) and not(exists(f:contained/*/f:meta/f:lastUpdated))"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/DomainResource"/> 
      </constraint> 
      <constraint> 
        <key value="dom-5"/> 
        <severity value="error"/> 
        <human value="If a resource is contained in another resource, it SHALL NOT have a security label"/> 
        <expression value="contained.meta.security.empty()"/> 
        <xpath value="not(exists(f:contained/*/f:meta/f:security))"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/DomainResource"/> 
      </constraint> 
      <constraint> 
        <extension url="http://hl7.org/fhir/StructureDefinition/elementdefinition-bestpractice">
          <valueBoolean value="true"/> 
        </extension> 
        <extension url="http://hl7.org/fhir/StructureDefinition/elementdefinition-bestpractice-explanation">
          <valueMarkdown value="When a resource has no narrative, only systems that fully understand the data can display
           the resource to a human safely. Including a human readable representation in the resource
           makes for a much more robust eco-system and cheaper handling of resources by intermediary
           systems. Some ecosystems restrict distribution of resources to only those systems that
           do fully understand the resources, and as a consequence implementers may believe that
           the narrative is superfluous. However experience shows that such eco-systems often open
           up to new participants over time."/> 
        </extension> 
        <key value="dom-6"/> 
        <severity value="warning"/> 
        <human value="A resource should have narrative for robust management"/> 
        <expression value="text.`div`.exists()"/> 
        <xpath value="exists(f:text/h:div)"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/DomainResource"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
      <mapping> 
        <identity value="rim"/> 
        <map value="Entity. Role, or Act"/> 
      </mapping> 
      <mapping> 
        <identity value="rim"/> 
        <map value="N/A"/> 
      </mapping> 
    </element> 
    <element id="CodeSystem.id">
      <path value="CodeSystem.id"/> 
      <short value="Logical id of this artifact"/> 
      <definition value="The logical id of the resource, as used in the URL for the resource. Once assigned, this
       value never changes."/> 
      <comment value="The only time that a resource does not have an id is when it is being submitted to the
       server using a create operation."/> 
      <min value="0"/> 
      <max value="1"/> 
      <base> 
        <path value="Resource.id"/> 
        <min value="0"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <extension url="http://hl7.org/fhir/StructureDefinition/structuredefinition-fhir-type">
          <valueUrl value="string"/> 
        </extension> 
        <code value="http://hl7.org/fhirpath/System.String"/> 
      </type> 
      <isModifier value="false"/> 
      <isSummary value="true"/> 
    </element> 
    <element id="CodeSystem.meta">
      <path value="CodeSystem.meta"/> 
      <short value="Metadata about the resource"/> 
      <definition value="The metadata about the resource. This is content that is maintained by the infrastructure.
       Changes to the content might not always be associated with version changes to the resource."/> 
      <min value="0"/> 
      <max value="1"/> 
      <base> 
        <path value="Resource.meta"/> 
        <min value="0"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="Meta"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="true"/> 
    </element> 
    <element id="CodeSystem.implicitRules">
      <path value="CodeSystem.implicitRules"/> 
      <short value="A set of rules under which this content was created"/> 
      <definition value="A reference to a set of rules that were followed when the resource was constructed, and
       which must be understood when processing the content. Often, this is a reference to an
       implementation guide that defines the special rules along with other profiles etc."/> 
      <comment value="Asserting this rule set restricts the content to be only understood by a limited set of
       trading partners. This inherently limits the usefulness of the data in the long term.
       However, the existing health eco-system is highly fractured, and not yet ready to define,
       collect, and exchange data in a generally computable sense. Wherever possible, implementers
       and/or specification writers should avoid using this element. Often, when used, the URL
       is a reference to an implementation guide that defines these special rules as part of
       it's narrative along with other profiles, value sets, etc."/> 
      <min value="0"/> 
      <max value="1"/> 
      <base> 
        <path value="Resource.implicitRules"/> 
        <min value="0"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="uri"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="true"/> 
      <isModifierReason value="This element is labeled as a modifier because the implicit rules may provide additional
       knowledge about the resource that modifies it's meaning or interpretation"/> 
      <isSummary value="true"/> 
    </element> 
    <element id="CodeSystem.language">
      <path value="CodeSystem.language"/> 
      <short value="Language of the resource content"/> 
      <definition value="The base language in which the resource is written."/> 
      <comment value="Language is provided to support indexing and accessibility (typically, services such as
       text to speech use the language tag). The html language tag in the narrative applies 
       to the narrative. The language tag on the resource may be used to specify the language
       of other presentations generated from the data in the resource. Not all the content has
       to be in the base language. The Resource.language should not be assumed to apply to the
       narrative automatically. If a language is specified, it should it also be specified on
       the div element in the html (see rules in HTML5 for information about the relationship
       between xml:lang and the html lang attribute)."/> 
      <min value="0"/> 
      <max value="1"/> 
      <base> 
        <path value="Resource.language"/> 
        <min value="0"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="code"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
      <binding> 
        <extension url="http://hl7.org/fhir/StructureDefinition/elementdefinition-maxValueSet">
          <valueCanonical value="http://hl7.org/fhir/ValueSet/all-languages"/> 
        </extension> 
        <extension url="http://hl7.org/fhir/StructureDefinition/elementdefinition-bindingName">
          <valueString value="Language"/> 
        </extension> 
        <extension url="http://hl7.org/fhir/StructureDefinition/elementdefinition-isCommonBinding">
          <valueBoolean value="true"/> 
        </extension> 
        <strength value="preferred"/> 
        <description value="A human language."/> 
        <valueSet value="http://hl7.org/fhir/ValueSet/languages"/> 
      </binding> 
    </element> 
    <element id="CodeSystem.text">
      <path value="CodeSystem.text"/> 
      <short value="Text summary of the resource, for human interpretation"/> 
      <definition value="A human-readable narrative that contains a summary of the resource and can be used to
       represent the content of the resource to a human. The narrative need not encode all the
       structured data, but is required to contain sufficient detail to make it &quot;clinically
       safe&quot; for a human to just read the narrative. Resource definitions may define what
       content should be represented in the narrative to ensure clinical safety."/> 
      <comment value="Contained resources do not have narrative. Resources that are not contained SHOULD have
       a narrative. In some cases, a resource may only have text with little or no additional
       discrete data (as long as all minOccurs=1 elements are satisfied).  This may be necessary
       for data from legacy systems where information is captured as a &quot;text blob&quot;
       or where text is additionally entered raw or narrated and encoded information is added
       later."/> 
      <alias value="narrative"/> 
      <alias value="html"/> 
      <alias value="xhtml"/> 
      <alias value="display"/> 
      <min value="0"/> 
      <max value="1"/> 
      <base> 
        <path value="DomainResource.text"/> 
        <min value="0"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="Narrative"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
      <mapping> 
        <identity value="rim"/> 
        <map value="Act.text?"/> 
      </mapping> 
    </element> 
    <element id="CodeSystem.contained">
      <path value="CodeSystem.contained"/> 
      <short value="Contained, inline Resources"/> 
      <definition value="These resources do not have an independent existence apart from the resource that contains
       them - they cannot be identified independently, and nor can they have their own independent
       transaction scope."/> 
      <comment value="This should never be done when the content can be identified properly, as once identification
       is lost, it is extremely difficult (and context dependent) to restore it again. Contained
       resources may have profiles and tags In their meta elements, but SHALL NOT have security
       labels."/> 
      <alias value="inline resources"/> 
      <alias value="anonymous resources"/> 
      <alias value="contained resources"/> 
      <min value="0"/> 
      <max value="*"/> 
      <base> 
        <path value="DomainResource.contained"/> 
        <min value="0"/> 
        <max value="*"/> 
      </base> 
      <type> 
        <code value="Resource"/> 
      </type> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
      <mapping> 
        <identity value="rim"/> 
        <map value="N/A"/> 
      </mapping> 
    </element> 
    <element id="CodeSystem.extension">
      <path value="CodeSystem.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 resource. 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
       can define an extension, there is a set of requirements that SHALL be met as part of the
       definition of the extension."/> 
      <comment 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="DomainResource.extension"/> 
        <min value="0"/> 
        <max value="*"/> 
      </base> 
      <type> 
        <code value="Extension"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <constraint> 
        <key value="ext-1"/> 
        <severity value="error"/> 
        <human value="Must have either extensions or value[x], not both"/> 
        <expression value="extension.exists() != value.exists()"/> 
        <xpath value="exists(f:extension)!=exists(f:*[starts-with(local-name(.), &quot;value&quot;)])"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Extension"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
      <mapping> 
        <identity value="rim"/> 
        <map value="N/A"/> 
      </mapping> 
    </element> 
    <element id="CodeSystem.modifierExtension">
      <path value="CodeSystem.modifierExtension"/> 
      <short value="Extensions that cannot be ignored"/> 
      <definition value="May be used to represent additional information that is not part of the basic definition
       of the resource and that modifies the understanding of the element that contains it and/or
       the understanding of the containing element's descendants. Usually modifier elements provide
       negation or qualification. 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. Applications processing a resource
       are required to check for modifier extensions.

Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource
       (including cannot change the meaning of modifierExtension itself)."/> 
      <comment 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."/> 
      <requirements value="Modifier extensions allow for extensions that *cannot* be safely ignored to be clearly
       distinguished from the vast majority of extensions which can be safely ignored.  This
       promotes interoperability by eliminating the need for implementers to prohibit the presence
       of extensions. For further information, see the [definition of modifier extensions](http://hl7.org/f
      hir/extensibility.html#modifierExtension)."/> 
      <alias value="extensions"/> 
      <alias value="user content"/> 
      <min value="0"/> 
      <max value="*"/> 
      <base> 
        <path value="DomainResource.modifierExtension"/> 
        <min value="0"/> 
        <max value="*"/> 
      </base> 
      <type> 
        <code value="Extension"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <constraint> 
        <key value="ext-1"/> 
        <severity value="error"/> 
        <human value="Must have either extensions or value[x], not both"/> 
        <expression value="extension.exists() != value.exists()"/> 
        <xpath value="exists(f:extension)!=exists(f:*[starts-with(local-name(.), &quot;value&quot;)])"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Extension"/> 
      </constraint> 
      <isModifier value="true"/> 
      <isModifierReason value="Modifier extensions are expected to modify the meaning or interpretation of the resource
       that contains them"/> 
      <isSummary value="false"/> 
      <mapping> 
        <identity value="rim"/> 
        <map value="N/A"/> 
      </mapping> 
    </element> 
    <element id="CodeSystem.url">
      <path value="CodeSystem.url"/> 
      <short value="Canonical identifier for this code system, represented as a URI (globally unique) (Coding.system)"/> 
      <definition value="An absolute URI that is used to identify this code system when it is referenced in a specification,
       model, design or an instance; also called its canonical identifier. This SHOULD be globally
       unique and SHOULD be a literal address at which at which an authoritative instance of
       this code system is (or will be) published. This URL can be the target of a canonical
       reference. It SHALL remain the same when the code system is stored on different servers.
       This is used in [Coding](http://hl7.org/fhir/datatypes.html#Coding).system."/> 
      <comment value="Can be a urn:uuid: or a urn:oid: but real http: addresses are preferred.  Multiple instances
       may share the same URL if they have a distinct version.

The determination of when to create a new version of a resource (same url, new version)
       vs. defining a new artifact is up to the author.  Considerations for making this decision
       are found in [Technical and Business Versions](http://hl7.org/fhir/resource.html#versions).
       

In some cases, the resource can no longer be found at the stated url, but the url itself
       cannot change. Implementations can use the [meta.source](http://hl7.org/fhir/resource.html#meta)
       element to indicate where the current master source of the resource can be found."/> 
      <requirements value="Allows the code system to be referenced by a single globally unique identifier."/> 
      <min value="1"/> 
      <max value="1"/> 
      <base> 
        <path value="CodeSystem.url"/> 
        <min value="0"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="uri"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="true"/> 
      <mapping> 
        <identity value="workflow"/> 
        <map value="Definition.url"/> 
      </mapping> 
      <mapping> 
        <identity value="w5"/> 
        <map value="FiveWs.identifier"/> 
      </mapping> 
    </element> 
    <element id="CodeSystem.identifier">
      <path value="CodeSystem.identifier"/> 
      <short value="Additional identifier for the code system (business identifier)"/> 
      <definition value="A formal identifier that is used to identify this code system when it is represented in
       other formats, or referenced in a specification, model, design or an instance."/> 
      <comment value="Typically, this is used for identifiers that can go in an HL7 V3 II (instance identifier)
       data type, and can then identify this code system outside of FHIR, where it is not possible
       to use the logical URI.  Note that HL7 defines at least three identifiers for many of
       its code systems - the FHIR canonical URL, the OID and the V2 Table 0396 mnemonic code."/> 
      <requirements value="Allows externally provided and/or usable business identifiers to be easily associated
       with the module."/> 
      <min value="0"/> 
      <max value="*"/> 
      <base> 
        <path value="CodeSystem.identifier"/> 
        <min value="0"/> 
        <max value="*"/> 
      </base> 
      <type> 
        <code value="Identifier"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="true"/> 
      <mapping> 
        <identity value="workflow"/> 
        <map value="Definition.identifier"/> 
      </mapping> 
      <mapping> 
        <identity value="w5"/> 
        <map value="FiveWs.identifier"/> 
      </mapping> 
      <mapping> 
        <identity value="objimpl"/> 
        <map value="no-gen-base"/> 
      </mapping> 
    </element> 
    <element id="CodeSystem.version">
      <path value="CodeSystem.version"/> 
      <short value="Business version of the code system (Coding.version)"/> 
      <definition value="The identifier that is used to identify this version of the code system when it is referenced
       in a specification, model, design or instance. This is an arbitrary value managed by the
       code system author and is not expected to be globally unique. For example, it might be
       a timestamp (e.g. yyyymmdd) if a managed version is not available. There is also no expectation
       that versions can be placed in a lexicographical sequence. This is used in [Coding](http://hl7.org/f
      hir/datatypes.html#Coding).version."/> 
      <comment value="There may be different code system instances that have the same identifier but different
       versions.  The version can be appended to the url in a reference to allow a reference
       to a particular business version of the code system with the format [url]|[version]."/> 
      <min value="1"/> 
      <max value="1"/> 
      <base> 
        <path value="CodeSystem.version"/> 
        <min value="0"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="string"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="true"/> 
      <mapping> 
        <identity value="workflow"/> 
        <map value="Definition.version"/> 
      </mapping> 
      <mapping> 
        <identity value="w5"/> 
        <map value="FiveWs.version"/> 
      </mapping> 
    </element> 
    <element id="CodeSystem.name">
      <path value="CodeSystem.name"/> 
      <short value="Name for this code system (computer friendly)"/> 
      <definition value="A natural language name identifying the code system. This name should be usable as an
       identifier for the module by machine processing applications such as code generation."/> 
      <comment value="The name is not expected to be globally unique. The name should be a simple alphanumeric
       type name to ensure that it is machine-processing friendly."/> 
      <requirements value="Support human navigation and code generation."/> 
      <min value="1"/> 
      <max value="1"/> 
      <base> 
        <path value="CodeSystem.name"/> 
        <min value="0"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="string"/> 
      </type> 
      <condition value="inv-0"/> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="true"/> 
    </element> 
    <element id="CodeSystem.title">
      <path value="CodeSystem.title"/> 
      <short value="Name for this code system (human friendly)"/> 
      <definition value="A short, descriptive, user-friendly title for the code system."/> 
      <comment value="This name does not need to be machine-processing friendly and may contain punctuation,
       white-space, etc."/> 
      <min value="0"/> 
      <max value="1"/> 
      <base> 
        <path value="CodeSystem.title"/> 
        <min value="0"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="string"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="true"/> 
      <mapping> 
        <identity value="workflow"/> 
        <map value="Definition.title"/> 
      </mapping> 
    </element> 
    <element id="CodeSystem.status">
      <path value="CodeSystem.status"/> 
      <short value="draft | active | retired | unknown"/> 
      <definition value="The date (and optionally time) when the code system resource was created or revised."/> 
      <comment value="Allows filtering of code systems that are appropriate for use versus not."/> 
      <min value="1"/> 
      <max value="1"/> 
      <base> 
        <path value="CodeSystem.status"/> 
        <min value="1"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="code"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="true"/> 
      <isModifierReason value="This is labeled as &quot;Is Modifier&quot; because applications should not use a retired
       {{title}} without due consideration"/> 
      <isSummary value="true"/> 
      <binding> 
        <extension url="http://hl7.org/fhir/StructureDefinition/elementdefinition-bindingName">
          <valueString value="PublicationStatus"/> 
        </extension> 
        <extension url="http://hl7.org/fhir/StructureDefinition/elementdefinition-isCommonBinding">
          <valueBoolean value="true"/> 
        </extension> 
        <strength value="required"/> 
        <description value="The lifecycle status of an artifact."/> 
        <valueSet value="http://hl7.org/fhir/ValueSet/publication-status|4.0.1"/> 
      </binding> 
      <mapping> 
        <identity value="workflow"/> 
        <map value="Definition.status"/> 
      </mapping> 
      <mapping> 
        <identity value="w5"/> 
        <map value="FiveWs.status"/> 
      </mapping> 
      <mapping> 
        <identity value="rim"/> 
        <map value="N/A"/> 
      </mapping> 
    </element> 
    <element id="CodeSystem.experimental">
      <path value="CodeSystem.experimental"/> 
      <short value="For testing purposes, not real usage"/> 
      <definition value="A Boolean value to indicate that this code system is authored for testing purposes (or
       education/evaluation/marketing) and is not intended to be used for genuine usage."/> 
      <comment value="Allows filtering of code systems that are appropriate for use versus not."/> 
      <requirements value="Enables experimental content to be developed following the same lifecycle that would be
       used for a production-level code system."/> 
      <min value="1"/> 
      <max value="1"/> 
      <base> 
        <path value="CodeSystem.experimental"/> 
        <min value="0"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="boolean"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="true"/> 
      <mapping> 
        <identity value="workflow"/> 
        <map value="Definition.experimental"/> 
      </mapping> 
      <mapping> 
        <identity value="w5"/> 
        <map value="FiveWs.class"/> 
      </mapping> 
    </element> 
    <element id="CodeSystem.date">
      <path value="CodeSystem.date"/> 
      <short value="Date last changed"/> 
      <definition value="The date  (and optionally time) when the code system was published. The date must change
       when the business version changes and it must change if the status code changes. In addition,
       it should change when the substantive content of the code system changes."/> 
      <comment value="Note that this is not the same as the resource last-modified-date, since the resource
       may be a secondary representation of the code system. Additional specific dates may be
       added as extensions or be found by consulting Provenances associated with past versions
       of the resource."/> 
      <alias value="Revision Date"/> 
      <min value="0"/> 
      <max value="1"/> 
      <base> 
        <path value="CodeSystem.date"/> 
        <min value="0"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="dateTime"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="true"/> 
      <mapping> 
        <identity value="workflow"/> 
        <map value="Definition.date"/> 
      </mapping> 
      <mapping> 
        <identity value="w5"/> 
        <map value="FiveWs.recorded"/> 
      </mapping> 
    </element> 
    <element id="CodeSystem.publisher">
      <path value="CodeSystem.publisher"/> 
      <short value="Name of the publisher (organization or individual)"/> 
      <definition value="The name of the organization or individual that published the code system."/> 
      <comment value="Usually an organization but may be an individual. The publisher (or steward) of the code
       system is the organization or individual primarily responsible for the maintenance and
       upkeep of the code system. This is not necessarily the same individual or organization
       that developed and initially authored the content. The publisher is the primary point
       of contact for questions or issues with the code system. This item SHOULD be populated
       unless the information is available from context."/> 
      <requirements value="Helps establish the &quot;authority/credibility&quot; of the code system.  May also allow
       for contact."/> 
      <alias value="steward"/> 
      <min value="1"/> 
      <max value="1"/> 
      <base> 
        <path value="CodeSystem.publisher"/> 
        <min value="0"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="string"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="true"/> 
      <mapping> 
        <identity value="workflow"/> 
        <map value="Definition.publisher"/> 
      </mapping> 
      <mapping> 
        <identity value="w5"/> 
        <map value="FiveWs.witness"/> 
      </mapping> 
    </element> 
    <element id="CodeSystem.contact">
      <path value="CodeSystem.contact"/> 
      <short value="Contact details for the publisher"/> 
      <definition value="Contact details to assist a user in finding and communicating with the publisher."/> 
      <comment value="May be a web site, an email address, a telephone number, etc."/> 
      <min value="0"/> 
      <max value="*"/> 
      <base> 
        <path value="CodeSystem.contact"/> 
        <min value="0"/> 
        <max value="*"/> 
      </base> 
      <type> 
        <code value="ContactDetail"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="true"/> 
      <mapping> 
        <identity value="workflow"/> 
        <map value="Definition.contact"/> 
      </mapping> 
    </element> 
    <element id="CodeSystem.description">
      <path value="CodeSystem.description"/> 
      <short value="Natural language description of the code system"/> 
      <definition value="A free text natural language description of the code system from a consumer's perspective."/> 
      <comment value="This description can be used to capture details such as why the code system was built,
       comments about misuse, instructions for clinical use and interpretation, literature references,
       examples from the paper world, etc. It is not a rendering of the code system as conveyed
       in the 'text' field of the resource itself. This item SHOULD be populated unless the information
       is available from context (e.g. the language of the code system is presumed to be the
       predominant language in the place the code system was created)."/> 
      <alias value="Scope"/> 
      <alias value="Purpose"/> 
      <alias value="scope"/> 
      <min value="1"/> 
      <max value="1"/> 
      <base> 
        <path value="CodeSystem.description"/> 
        <min value="0"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="markdown"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
      <mapping> 
        <identity value="workflow"/> 
        <map value="Definition.description"/> 
      </mapping> 
      <mapping> 
        <identity value="rim"/> 
        <map value="N/A"/> 
      </mapping> 
    </element> 
    <element id="CodeSystem.useContext">
      <extension url="http://hl7.org/fhir/StructureDefinition/structuredefinition-standards-status">
        <valueCode value="trial-use"/> 
      </extension> 
      <path value="CodeSystem.useContext"/> 
      <short value="The context that the content is intended to support"/> 
      <definition value="The content was developed with a focus and intent of supporting the contexts that are
       listed. These contexts may be general categories (gender, age, ...) or may be references
       to specific programs (insurance plans, studies, ...) and may be used to assist with indexing
       and searching for appropriate code system instances."/> 
      <comment value="When multiple useContexts are specified, there is no expectation that all or any of the
       contexts apply."/> 
      <requirements value="Assist in searching for appropriate content."/> 
      <min value="0"/> 
      <max value="*"/> 
      <base> 
        <path value="CodeSystem.useContext"/> 
        <min value="0"/> 
        <max value="*"/> 
      </base> 
      <type> 
        <code value="UsageContext"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="true"/> 
      <mapping> 
        <identity value="workflow"/> 
        <map value="Definition.useContext"/> 
      </mapping> 
    </element> 
    <element id="CodeSystem.jurisdiction">
      <path value="CodeSystem.jurisdiction"/> 
      <short value="Intended jurisdiction for code system (if applicable)"/> 
      <definition value="A legal or geographic region in which the code system is intended to be used."/> 
      <comment value="It may be possible for the code system to be used in jurisdictions other than those for
       which it was originally designed or intended."/> 
      <min value="0"/> 
      <max value="*"/> 
      <base> 
        <path value="CodeSystem.jurisdiction"/> 
        <min value="0"/> 
        <max value="*"/> 
      </base> 
      <type> 
        <code value="CodeableConcept"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="true"/> 
      <binding> 
        <extension url="http://hl7.org/fhir/StructureDefinition/elementdefinition-bindingName">
          <valueString value="Jurisdiction"/> 
        </extension> 
        <extension url="http://hl7.org/fhir/StructureDefinition/elementdefinition-isCommonBinding">
          <valueBoolean value="true"/> 
        </extension> 
        <strength value="extensible"/> 
        <description value="Countries and regions within which this artifact is targeted for use."/> 
        <valueSet value="http://hl7.org/fhir/ValueSet/jurisdiction"/> 
      </binding> 
      <mapping> 
        <identity value="workflow"/> 
        <map value="Definition.jurisdiction"/> 
      </mapping> 
    </element> 
    <element id="CodeSystem.purpose">
      <path value="CodeSystem.purpose"/> 
      <short value="Why this code system is defined"/> 
      <definition value="Explanation of why this code system is needed and why it has been designed as it has."/> 
      <comment value="This element does not describe the usage of the code system. Instead, it provides traceability
       of ''why'' the resource is either needed or ''why'' it is defined as it is.  This may
       be used to point to source materials or specifications that drove the structure of this
       code system."/> 
      <min value="0"/> 
      <max value="1"/> 
      <base> 
        <path value="CodeSystem.purpose"/> 
        <min value="0"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="markdown"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
      <mapping> 
        <identity value="workflow"/> 
        <map value="Definition.purpose"/> 
      </mapping> 
      <mapping> 
        <identity value="w5"/> 
        <map value="FiveWs.why[x]"/> 
      </mapping> 
      <mapping> 
        <identity value="objimpl"/> 
        <map value="no-gen-base"/> 
      </mapping> 
    </element> 
    <element id="CodeSystem.copyright">
      <path value="CodeSystem.copyright"/> 
      <short value="Use and/or publishing restrictions"/> 
      <definition value="A copyright statement relating to the code system and/or its contents. Copyright statements
       are generally legal restrictions on the use and publishing of the code system."/> 
      <comment value="... Sometimes, the copyright differs between the code system and the codes that are included.
       The copyright statement should clearly differentiate between these when required."/> 
      <requirements value="Consumers must be able to determine any legal restrictions on the use of the code system
       and/or its content."/> 
      <alias value="License"/> 
      <alias value="Restrictions"/> 
      <min value="0"/> 
      <max value="1"/> 
      <base> 
        <path value="CodeSystem.copyright"/> 
        <min value="0"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="markdown"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
      <mapping> 
        <identity value="workflow"/> 
        <map value="Definition.copyright"/> 
      </mapping> 
      <mapping> 
        <identity value="objimpl"/> 
        <map value="no-gen-base"/> 
      </mapping> 
    </element> 
    <element id="CodeSystem.caseSensitive">
      <path value="CodeSystem.caseSensitive"/> 
      <short value="If code comparison is case sensitive"/> 
      <definition value="If code comparison is case sensitive when codes within this system are compared to each
       other."/> 
      <comment value="If this value is missing, then it is not specified whether a code system is case sensitive
       or not. When the rule is not known, Postel's law should be followed: produce codes with
       the correct case, and accept codes in any case. This element is primarily provided to
       support validation software."/> 
      <min value="0"/> 
      <max value="1"/> 
      <base> 
        <path value="CodeSystem.caseSensitive"/> 
        <min value="0"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="boolean"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="true"/> 
    </element> 
    <element id="CodeSystem.valueSet">
      <path value="CodeSystem.valueSet"/> 
      <short value="Canonical reference to the value set with entire code system"/> 
      <definition value="Canonical reference to the value set that contains the entire code system."/> 
      <comment value="The definition of the value set SHALL include all codes from this code system and only
       codes from this code system, and it SHALL be immutable."/> 
      <min value="0"/> 
      <max value="1"/> 
      <base> 
        <path value="CodeSystem.valueSet"/> 
        <min value="0"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="canonical"/> 
        <targetProfile value="http://hl7.org/fhir/StructureDefinition/ValueSet"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="true"/> 
    </element> 
    <element id="CodeSystem.hierarchyMeaning">
      <path value="CodeSystem.hierarchyMeaning"/> 
      <short value="grouped-by | is-a | part-of | classified-with"/> 
      <definition value="The meaning of the hierarchy of concepts as represented in this resource."/> 
      <comment value="Note that other representations might have a different hierarchy or none at all, and represent
       the information using properties."/> 
      <min value="0"/> 
      <max value="1"/> 
      <base> 
        <path value="CodeSystem.hierarchyMeaning"/> 
        <min value="0"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="code"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="true"/> 
      <binding> 
        <extension url="http://hl7.org/fhir/StructureDefinition/elementdefinition-bindingName">
          <valueString value="CodeSystemHierarchyMeaning"/> 
        </extension> 
        <strength value="required"/> 
        <description value="The meaning of the hierarchy of concepts in a code system."/> 
        <valueSet value="http://hl7.org/fhir/ValueSet/codesystem-hierarchy-meaning|4.0.1"/> 
      </binding> 
    </element> 
    <element id="CodeSystem.compositional">
      <path value="CodeSystem.compositional"/> 
      <short value="If code system defines a compositional grammar"/> 
      <definition value="The code system defines a compositional (post-coordination) grammar."/> 
      <comment value="Note that the code system resource does not define what the compositional grammar is,
       only whether or not there is one."/> 
      <alias value="grammar"/> 
      <min value="0"/> 
      <max value="1"/> 
      <base> 
        <path value="CodeSystem.compositional"/> 
        <min value="0"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="boolean"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="true"/> 
    </element> 
    <element id="CodeSystem.versionNeeded">
      <path value="CodeSystem.versionNeeded"/> 
      <short value="If definitions are not stable"/> 
      <definition value="This flag is used to signify that the code system does not commit to concept permanence
       across versions. If true, a version must be specified when referencing this code system."/> 
      <comment value="Best practice is that code systems do not redefine concepts, or that if concepts are redefined,
       a new code system definition is created. But this is not always possible, so some code
       systems may be defined as 'versionNeeded'.

Most code systems occasionally refine the displays defined for concepts between versions.
       Contexts in which the concept display values are validated may require that the version
       be specified for some code systems irrespective of the value of this property."/> 
      <min value="0"/> 
      <max value="1"/> 
      <base> 
        <path value="CodeSystem.versionNeeded"/> 
        <min value="0"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="boolean"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="true"/> 
    </element> 
    <element id="CodeSystem.content">
      <path value="CodeSystem.content"/> 
      <short value="not-present | example | fragment | complete | supplement"/> 
      <definition value="The extent of the content of the code system (the concepts and codes it defines) are represented
       in this resource instance."/> 
      <min value="1"/> 
      <max value="1"/> 
      <base> 
        <path value="CodeSystem.content"/> 
        <min value="1"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="code"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="true"/> 
      <binding> 
        <extension url="http://hl7.org/fhir/StructureDefinition/elementdefinition-bindingName">
          <valueString value="CodeSystemContentMode"/> 
        </extension> 
        <strength value="required"/> 
        <description value="The extent of the content of the code system (the concepts and codes it defines) are represented
         in a code system resource."/> 
        <valueSet value="http://hl7.org/fhir/ValueSet/codesystem-content-mode|4.0.1"/> 
      </binding> 
    </element> 
    <element id="CodeSystem.supplements">
      <path value="CodeSystem.supplements"/> 
      <short value="Canonical URL of Code System this adds designations and properties to"/> 
      <definition value="The canonical URL of the code system that this code system supplement is adding designations
       and properties to."/> 
      <comment value="The most common use of a code system supplement is to add additional language support."/> 
      <min value="0"/> 
      <max value="1"/> 
      <base> 
        <path value="CodeSystem.supplements"/> 
        <min value="0"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="canonical"/> 
        <targetProfile value="http://hl7.org/fhir/StructureDefinition/CodeSystem"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="true"/> 
    </element> 
    <element id="CodeSystem.count">
      <path value="CodeSystem.count"/> 
      <short value="Total concepts in the code system"/> 
      <definition value="The total number of concepts defined by the code system. Where the code system has a compositional
       grammar, the basis of this count is defined by the system steward."/> 
      <comment value="The count of concepts defined in this resource cannot be more than this value but may
       be less for several reasons - see the content element."/> 
      <min value="0"/> 
      <max value="1"/> 
      <base> 
        <path value="CodeSystem.count"/> 
        <min value="0"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="unsignedInt"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="true"/> 
    </element> 
    <element id="CodeSystem.filter">
      <path value="CodeSystem.filter"/> 
      <short value="Filter that can be used in a value set"/> 
      <definition value="A filter that can be used in a value set compose statement when selecting concepts using
       a filter."/> 
      <comment value="Note that filters defined in code systems usually require custom code on the part of any
       terminology engine that will make them available for use in value set filters. For this
       reason, they are generally only seen in high value published terminologies."/> 
      <min value="0"/> 
      <max value="*"/> 
      <base> 
        <path value="CodeSystem.filter"/> 
        <min value="0"/> 
        <max value="*"/> 
      </base> 
      <type> 
        <code value="BackboneElement"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="true"/> 
    </element> 
    <element id="CodeSystem.filter.id">
      <path value="CodeSystem.filter.id"/> 
      <representation value="xmlAttr"/> 
      <short value="Unique id for inter-element referencing"/> 
      <definition value="Unique id for the element within a resource (for internal references). This may be any
       string value that does not contain spaces."/> 
      <min value="0"/> 
      <max value="1"/> 
      <base> 
        <path value="Element.id"/> 
        <min value="0"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <extension url="http://hl7.org/fhir/StructureDefinition/structuredefinition-fhir-type">
          <valueUrl value="string"/> 
        </extension> 
        <code value="http://hl7.org/fhirpath/System.String"/> 
      </type> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
      <mapping> 
        <identity value="rim"/> 
        <map value="n/a"/> 
      </mapping> 
    </element> 
    <element id="CodeSystem.filter.extension">
      <path value="CodeSystem.filter.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. 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
       can define an extension, there is a set of requirements that SHALL be met as part of the
       definition of the extension."/> 
      <comment 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="Element.extension"/> 
        <min value="0"/> 
        <max value="*"/> 
      </base> 
      <type> 
        <code value="Extension"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <constraint> 
        <key value="ext-1"/> 
        <severity value="error"/> 
        <human value="Must have either extensions or value[x], not both"/> 
        <expression value="extension.exists() != value.exists()"/> 
        <xpath value="exists(f:extension)!=exists(f:*[starts-with(local-name(.), &quot;value&quot;)])"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Extension"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
      <mapping> 
        <identity value="rim"/> 
        <map value="n/a"/> 
      </mapping> 
    </element> 
    <element id="CodeSystem.filter.modifierExtension">
      <path value="CodeSystem.filter.modifierExtension"/> 
      <short value="Extensions that cannot be ignored even if unrecognized"/> 
      <definition value="May be used to represent additional information that is not part of the basic definition
       of the element and that modifies the understanding of the element in which it is contained
       and/or the understanding of the containing element's descendants. Usually modifier elements
       provide negation or qualification. 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 can define an extension, there is a set of requirements that SHALL be
       met as part of the definition of the extension. Applications processing a resource are
       required to check for modifier extensions.

Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource
       (including cannot change the meaning of modifierExtension itself)."/> 
      <comment 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."/> 
      <requirements value="Modifier extensions allow for extensions that *cannot* be safely ignored to be clearly
       distinguished from the vast majority of extensions which can be safely ignored.  This
       promotes interoperability by eliminating the need for implementers to prohibit the presence
       of extensions. For further information, see the [definition of modifier extensions](http://hl7.org/f
      hir/extensibility.html#modifierExtension)."/> 
      <alias value="extensions"/> 
      <alias value="user content"/> 
      <alias value="modifiers"/> 
      <min value="0"/> 
      <max value="*"/> 
      <base> 
        <path value="BackboneElement.modifierExtension"/> 
        <min value="0"/> 
        <max value="*"/> 
      </base> 
      <type> 
        <code value="Extension"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <constraint> 
        <key value="ext-1"/> 
        <severity value="error"/> 
        <human value="Must have either extensions or value[x], not both"/> 
        <expression value="extension.exists() != value.exists()"/> 
        <xpath value="exists(f:extension)!=exists(f:*[starts-with(local-name(.), &quot;value&quot;)])"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Extension"/> 
      </constraint> 
      <isModifier value="true"/> 
      <isModifierReason value="Modifier extensions are expected to modify the meaning or interpretation of the element
       that contains them"/> 
      <isSummary value="true"/> 
      <mapping> 
        <identity value="rim"/> 
        <map value="N/A"/> 
      </mapping> 
    </element> 
    <element id="CodeSystem.filter.code">
      <path value="CodeSystem.filter.code"/> 
      <short value="Code that identifies the filter"/> 
      <definition value="The code that identifies this filter when it is used as a filter in [ValueSet](http://hl7.org/fhir/v
      alueset.html#).compose.include.filter."/> 
      <min value="1"/> 
      <max value="1"/> 
      <base> 
        <path value="CodeSystem.filter.code"/> 
        <min value="1"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="code"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="true"/> 
    </element> 
    <element id="CodeSystem.filter.description">
      <path value="CodeSystem.filter.description"/> 
      <short value="How or why the filter is used"/> 
      <definition value="A description of how or why the filter is used."/> 
      <min value="0"/> 
      <max value="1"/> 
      <base> 
        <path value="CodeSystem.filter.description"/> 
        <min value="0"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="string"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="true"/> 
    </element> 
    <element id="CodeSystem.filter.operator">
      <path value="CodeSystem.filter.operator"/> 
      <short value="= | is-a | descendent-of | is-not-a | regex | in | not-in | generalizes | exists"/> 
      <definition value="A list of operators that can be used with the filter."/> 
      <min value="1"/> 
      <max value="*"/> 
      <base> 
        <path value="CodeSystem.filter.operator"/> 
        <min value="1"/> 
        <max value="*"/> 
      </base> 
      <type> 
        <code value="code"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="true"/> 
      <binding> 
        <extension url="http://hl7.org/fhir/StructureDefinition/elementdefinition-bindingName">
          <valueString value="FilterOperator"/> 
        </extension> 
        <strength value="required"/> 
        <description value="The kind of operation to perform as a part of a property based filter."/> 
        <valueSet value="http://hl7.org/fhir/ValueSet/filter-operator|4.0.1"/> 
      </binding> 
    </element> 
    <element id="CodeSystem.filter.value">
      <path value="CodeSystem.filter.value"/> 
      <short value="What to use for the value"/> 
      <definition value="A description of what the value for the filter should be."/> 
      <min value="1"/> 
      <max value="1"/> 
      <base> 
        <path value="CodeSystem.filter.value"/> 
        <min value="1"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="string"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="true"/> 
    </element> 
    <element id="CodeSystem.property">
      <extension url="http://hl7.org/fhir/StructureDefinition/structuredefinition-explicit-type-name">
        <valueString value="Property"/> 
      </extension> 
      <path value="CodeSystem.property"/> 
      <short value="Additional information supplied about each concept"/> 
      <definition value="A property defines an additional slot through which additional information can be provided
       about a concept."/> 
      <min value="0"/> 
      <max value="*"/> 
      <base> 
        <path value="CodeSystem.property"/> 
        <min value="0"/> 
        <max value="*"/> 
      </base> 
      <type> 
        <code value="BackboneElement"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="true"/> 
    </element> 
    <element id="CodeSystem.property.id">
      <path value="CodeSystem.property.id"/> 
      <representation value="xmlAttr"/> 
      <short value="Unique id for inter-element referencing"/> 
      <definition value="Unique id for the element within a resource (for internal references). This may be any
       string value that does not contain spaces."/> 
      <min value="0"/> 
      <max value="1"/> 
      <base> 
        <path value="Element.id"/> 
        <min value="0"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <extension url="http://hl7.org/fhir/StructureDefinition/structuredefinition-fhir-type">
          <valueUrl value="string"/> 
        </extension> 
        <code value="http://hl7.org/fhirpath/System.String"/> 
      </type> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
      <mapping> 
        <identity value="rim"/> 
        <map value="n/a"/> 
      </mapping> 
    </element> 
    <element id="CodeSystem.property.extension">
      <path value="CodeSystem.property.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. 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
       can define an extension, there is a set of requirements that SHALL be met as part of the
       definition of the extension."/> 
      <comment 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="Element.extension"/> 
        <min value="0"/> 
        <max value="*"/> 
      </base> 
      <type> 
        <code value="Extension"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <constraint> 
        <key value="ext-1"/> 
        <severity value="error"/> 
        <human value="Must have either extensions or value[x], not both"/> 
        <expression value="extension.exists() != value.exists()"/> 
        <xpath value="exists(f:extension)!=exists(f:*[starts-with(local-name(.), &quot;value&quot;)])"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Extension"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
      <mapping> 
        <identity value="rim"/> 
        <map value="n/a"/> 
      </mapping> 
    </element> 
    <element id="CodeSystem.property.modifierExtension">
      <path value="CodeSystem.property.modifierExtension"/> 
      <short value="Extensions that cannot be ignored even if unrecognized"/> 
      <definition value="May be used to represent additional information that is not part of the basic definition
       of the element and that modifies the understanding of the element in which it is contained
       and/or the understanding of the containing element's descendants. Usually modifier elements
       provide negation or qualification. 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 can define an extension, there is a set of requirements that SHALL be
       met as part of the definition of the extension. Applications processing a resource are
       required to check for modifier extensions.

Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource
       (including cannot change the meaning of modifierExtension itself)."/> 
      <comment 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."/> 
      <requirements value="Modifier extensions allow for extensions that *cannot* be safely ignored to be clearly
       distinguished from the vast majority of extensions which can be safely ignored.  This
       promotes interoperability by eliminating the need for implementers to prohibit the presence
       of extensions. For further information, see the [definition of modifier extensions](http://hl7.org/f
      hir/extensibility.html#modifierExtension)."/> 
      <alias value="extensions"/> 
      <alias value="user content"/> 
      <alias value="modifiers"/> 
      <min value="0"/> 
      <max value="*"/> 
      <base> 
        <path value="BackboneElement.modifierExtension"/> 
        <min value="0"/> 
        <max value="*"/> 
      </base> 
      <type> 
        <code value="Extension"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <constraint> 
        <key value="ext-1"/> 
        <severity value="error"/> 
        <human value="Must have either extensions or value[x], not both"/> 
        <expression value="extension.exists() != value.exists()"/> 
        <xpath value="exists(f:extension)!=exists(f:*[starts-with(local-name(.), &quot;value&quot;)])"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Extension"/> 
      </constraint> 
      <isModifier value="true"/> 
      <isModifierReason value="Modifier extensions are expected to modify the meaning or interpretation of the element
       that contains them"/> 
      <isSummary value="true"/> 
      <mapping> 
        <identity value="rim"/> 
        <map value="N/A"/> 
      </mapping> 
    </element> 
    <element id="CodeSystem.property.code">
      <path value="CodeSystem.property.code"/> 
      <short value="Identifies the property on the concepts, and when referred to in operations"/> 
      <definition value="A code that is used to identify the property. The code is used internally (in CodeSystem.concept.pro
      perty.code) and also externally, such as in property filters."/> 
      <min value="1"/> 
      <max value="1"/> 
      <base> 
        <path value="CodeSystem.property.code"/> 
        <min value="1"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="code"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="true"/> 
    </element> 
    <element id="CodeSystem.property.uri">
      <path value="CodeSystem.property.uri"/> 
      <short value="Formal identifier for the property"/> 
      <definition value="Reference to the formal meaning of the property. One possible source of meaning is the
       [Concept Properties](http://hl7.org/fhir/codesystem-concept-properties.html) code system."/> 
      <min value="0"/> 
      <max value="1"/> 
      <base> 
        <path value="CodeSystem.property.uri"/> 
        <min value="0"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="uri"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="true"/> 
    </element> 
    <element id="CodeSystem.property.description">
      <path value="CodeSystem.property.description"/> 
      <short value="Why the property is defined, and/or what it conveys"/> 
      <definition value="A description of the property- why it is defined, and how its value might be used."/> 
      <min value="0"/> 
      <max value="1"/> 
      <base> 
        <path value="CodeSystem.property.description"/> 
        <min value="0"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="string"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="true"/> 
    </element> 
    <element id="CodeSystem.property.type">
      <path value="CodeSystem.property.type"/> 
      <short value="code | Coding | string | integer | boolean | dateTime | decimal"/> 
      <definition value="The type of the property value. Properties of type &quot;code&quot; contain a code defined
       by the code system (e.g. a reference to another defined concept)."/> 
      <min value="1"/> 
      <max value="1"/> 
      <base> 
        <path value="CodeSystem.property.type"/> 
        <min value="1"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="code"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="true"/> 
      <binding> 
        <extension url="http://hl7.org/fhir/StructureDefinition/elementdefinition-bindingName">
          <valueString value="PropertyType"/> 
        </extension> 
        <strength value="required"/> 
        <description value="The type of a property value."/> 
        <valueSet value="http://hl7.org/fhir/ValueSet/concept-property-type|4.0.1"/> 
      </binding> 
    </element> 
    <element id="CodeSystem.concept">
      <extension url="http://hl7.org/fhir/StructureDefinition/structuredefinition-explicit-type-name">
        <valueString value="ConceptDefinition"/> 
      </extension> 
      <path value="CodeSystem.concept"/> 
      <short value="Concepts in the code system"/> 
      <definition value="Concepts that are in the code system. The concept definitions are inherently hierarchical,
       but the definitions must be consulted to determine what the meanings of the hierarchical
       relationships are."/> 
      <comment value="If this is empty, it means that the code system resource does not represent the content
       of the code system."/> 
      <min value="1"/> 
      <max value="*"/> 
      <base> 
        <path value="CodeSystem.concept"/> 
        <min value="0"/> 
        <max value="*"/> 
      </base> 
      <type> 
        <code value="BackboneElement"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
    </element> 
    <element id="CodeSystem.concept.id">
      <path value="CodeSystem.concept.id"/> 
      <representation value="xmlAttr"/> 
      <short value="Unique id for inter-element referencing"/> 
      <definition value="Unique id for the element within a resource (for internal references). This may be any
       string value that does not contain spaces."/> 
      <min value="0"/> 
      <max value="1"/> 
      <base> 
        <path value="Element.id"/> 
        <min value="0"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <extension url="http://hl7.org/fhir/StructureDefinition/structuredefinition-fhir-type">
          <valueUrl value="string"/> 
        </extension> 
        <code value="http://hl7.org/fhirpath/System.String"/> 
      </type> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
      <mapping> 
        <identity value="rim"/> 
        <map value="n/a"/> 
      </mapping> 
    </element> 
    <element id="CodeSystem.concept.extension">
      <path value="CodeSystem.concept.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. 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
       can define an extension, there is a set of requirements that SHALL be met as part of the
       definition of the extension."/> 
      <comment 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="Element.extension"/> 
        <min value="0"/> 
        <max value="*"/> 
      </base> 
      <type> 
        <code value="Extension"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <constraint> 
        <key value="ext-1"/> 
        <severity value="error"/> 
        <human value="Must have either extensions or value[x], not both"/> 
        <expression value="extension.exists() != value.exists()"/> 
        <xpath value="exists(f:extension)!=exists(f:*[starts-with(local-name(.), &quot;value&quot;)])"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Extension"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
      <mapping> 
        <identity value="rim"/> 
        <map value="n/a"/> 
      </mapping> 
    </element> 
    <element id="CodeSystem.concept.modifierExtension">
      <path value="CodeSystem.concept.modifierExtension"/> 
      <short value="Extensions that cannot be ignored even if unrecognized"/> 
      <definition value="May be used to represent additional information that is not part of the basic definition
       of the element and that modifies the understanding of the element in which it is contained
       and/or the understanding of the containing element's descendants. Usually modifier elements
       provide negation or qualification. 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 can define an extension, there is a set of requirements that SHALL be
       met as part of the definition of the extension. Applications processing a resource are
       required to check for modifier extensions.

Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource
       (including cannot change the meaning of modifierExtension itself)."/> 
      <comment 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."/> 
      <requirements value="Modifier extensions allow for extensions that *cannot* be safely ignored to be clearly
       distinguished from the vast majority of extensions which can be safely ignored.  This
       promotes interoperability by eliminating the need for implementers to prohibit the presence
       of extensions. For further information, see the [definition of modifier extensions](http://hl7.org/f
      hir/extensibility.html#modifierExtension)."/> 
      <alias value="extensions"/> 
      <alias value="user content"/> 
      <alias value="modifiers"/> 
      <min value="0"/> 
      <max value="*"/> 
      <base> 
        <path value="BackboneElement.modifierExtension"/> 
        <min value="0"/> 
        <max value="*"/> 
      </base> 
      <type> 
        <code value="Extension"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <constraint> 
        <key value="ext-1"/> 
        <severity value="error"/> 
        <human value="Must have either extensions or value[x], not both"/> 
        <expression value="extension.exists() != value.exists()"/> 
        <xpath value="exists(f:extension)!=exists(f:*[starts-with(local-name(.), &quot;value&quot;)])"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Extension"/> 
      </constraint> 
      <isModifier value="true"/> 
      <isModifierReason value="Modifier extensions are expected to modify the meaning or interpretation of the element
       that contains them"/> 
      <isSummary value="true"/> 
      <mapping> 
        <identity value="rim"/> 
        <map value="N/A"/> 
      </mapping> 
    </element> 
    <element id="CodeSystem.concept.code">
      <path value="CodeSystem.concept.code"/> 
      <short value="Code that identifies concept"/> 
      <definition value="A code - a text symbol - that uniquely identifies the concept within the code system."/> 
      <min value="1"/> 
      <max value="1"/> 
      <base> 
        <path value="CodeSystem.concept.code"/> 
        <min value="1"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="code"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
    </element> 
    <element id="CodeSystem.concept.display">
      <path value="CodeSystem.concept.display"/> 
      <short value="Text to display to the user"/> 
      <definition value="A human readable string that is the recommended default way to present this concept to
       a user."/> 
      <min value="0"/> 
      <max value="1"/> 
      <base> 
        <path value="CodeSystem.concept.display"/> 
        <min value="0"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="string"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
    </element> 
    <element id="CodeSystem.concept.definition">
      <path value="CodeSystem.concept.definition"/> 
      <short value="Formal definition"/> 
      <definition value="The formal definition of the concept. The code system resource does not make formal definitions
       required, because of the prevalence of legacy systems. However, they are highly recommended,
       as without them there is no formal meaning associated with the concept."/> 
      <min value="0"/> 
      <max value="1"/> 
      <base> 
        <path value="CodeSystem.concept.definition"/> 
        <min value="0"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="string"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
    </element> 
    <element id="CodeSystem.concept.designation">
      <path value="CodeSystem.concept.designation"/> 
      <short value="Additional representations for the concept"/> 
      <definition value="Additional representations for the concept - other languages, aliases, specialized purposes,
       used for particular purposes, etc."/> 
      <comment value="Concepts have both a ```display``` and an array of ```designation```. The display is equivalent
       to a special designation with an implied ```designation.use``` of &quot;primary code&quot;
       and a language equal to the [Resource Language](http://hl7.org/fhir/resource.html#language)."/> 
      <requirements value="Many concept definition systems support multiple representations, in multiple languages,
       and for multiple purposes."/> 
      <min value="0"/> 
      <max value="*"/> 
      <base> 
        <path value="CodeSystem.concept.designation"/> 
        <min value="0"/> 
        <max value="*"/> 
      </base> 
      <type> 
        <code value="BackboneElement"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
    </element> 
    <element id="CodeSystem.concept.designation.id">
      <path value="CodeSystem.concept.designation.id"/> 
      <representation value="xmlAttr"/> 
      <short value="Unique id for inter-element referencing"/> 
      <definition value="Unique id for the element within a resource (for internal references). This may be any
       string value that does not contain spaces."/> 
      <min value="0"/> 
      <max value="1"/> 
      <base> 
        <path value="Element.id"/> 
        <min value="0"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <extension url="http://hl7.org/fhir/StructureDefinition/structuredefinition-fhir-type">
          <valueUrl value="string"/> 
        </extension> 
        <code value="http://hl7.org/fhirpath/System.String"/> 
      </type> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
      <mapping> 
        <identity value="rim"/> 
        <map value="n/a"/> 
      </mapping> 
    </element> 
    <element id="CodeSystem.concept.designation.extension">
      <path value="CodeSystem.concept.designation.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. 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
       can define an extension, there is a set of requirements that SHALL be met as part of the
       definition of the extension."/> 
      <comment 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="Element.extension"/> 
        <min value="0"/> 
        <max value="*"/> 
      </base> 
      <type> 
        <code value="Extension"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <constraint> 
        <key value="ext-1"/> 
        <severity value="error"/> 
        <human value="Must have either extensions or value[x], not both"/> 
        <expression value="extension.exists() != value.exists()"/> 
        <xpath value="exists(f:extension)!=exists(f:*[starts-with(local-name(.), &quot;value&quot;)])"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Extension"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
      <mapping> 
        <identity value="rim"/> 
        <map value="n/a"/> 
      </mapping> 
    </element> 
    <element id="CodeSystem.concept.designation.modifierExtension">
      <path value="CodeSystem.concept.designation.modifierExtension"/> 
      <short value="Extensions that cannot be ignored even if unrecognized"/> 
      <definition value="May be used to represent additional information that is not part of the basic definition
       of the element and that modifies the understanding of the element in which it is contained
       and/or the understanding of the containing element's descendants. Usually modifier elements
       provide negation or qualification. 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 can define an extension, there is a set of requirements that SHALL be
       met as part of the definition of the extension. Applications processing a resource are
       required to check for modifier extensions.

Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource
       (including cannot change the meaning of modifierExtension itself)."/> 
      <comment 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."/> 
      <requirements value="Modifier extensions allow for extensions that *cannot* be safely ignored to be clearly
       distinguished from the vast majority of extensions which can be safely ignored.  This
       promotes interoperability by eliminating the need for implementers to prohibit the presence
       of extensions. For further information, see the [definition of modifier extensions](http://hl7.org/f
      hir/extensibility.html#modifierExtension)."/> 
      <alias value="extensions"/> 
      <alias value="user content"/> 
      <alias value="modifiers"/> 
      <min value="0"/> 
      <max value="*"/> 
      <base> 
        <path value="BackboneElement.modifierExtension"/> 
        <min value="0"/> 
        <max value="*"/> 
      </base> 
      <type> 
        <code value="Extension"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <constraint> 
        <key value="ext-1"/> 
        <severity value="error"/> 
        <human value="Must have either extensions or value[x], not both"/> 
        <expression value="extension.exists() != value.exists()"/> 
        <xpath value="exists(f:extension)!=exists(f:*[starts-with(local-name(.), &quot;value&quot;)])"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Extension"/> 
      </constraint> 
      <isModifier value="true"/> 
      <isModifierReason value="Modifier extensions are expected to modify the meaning or interpretation of the element
       that contains them"/> 
      <isSummary value="true"/> 
      <mapping> 
        <identity value="rim"/> 
        <map value="N/A"/> 
      </mapping> 
    </element> 
    <element id="CodeSystem.concept.designation.language">
      <path value="CodeSystem.concept.designation.language"/> 
      <short value="Human language of the designation"/> 
      <definition value="The language this designation is defined for."/> 
      <comment value="In the absence of a language, the resource language applies."/> 
      <min value="0"/> 
      <max value="1"/> 
      <base> 
        <path value="CodeSystem.concept.designation.language"/> 
        <min value="0"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="code"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
      <binding> 
        <extension url="http://hl7.org/fhir/StructureDefinition/elementdefinition-maxValueSet">
          <valueCanonical value="http://hl7.org/fhir/ValueSet/all-languages"/> 
        </extension> 
        <extension url="http://hl7.org/fhir/StructureDefinition/elementdefinition-bindingName">
          <valueString value="Language"/> 
        </extension> 
        <extension url="http://hl7.org/fhir/StructureDefinition/elementdefinition-isCommonBinding">
          <valueBoolean value="true"/> 
        </extension> 
        <strength value="preferred"/> 
        <description value="A human language."/> 
        <valueSet value="http://hl7.org/fhir/ValueSet/languages"/> 
      </binding> 
    </element> 
    <element id="CodeSystem.concept.designation.use">
      <path value="CodeSystem.concept.designation.use"/> 
      <short value="Details how this designation would be used"/> 
      <definition value="A code that details how this designation would be used."/> 
      <comment value="If no use is provided, the designation can be assumed to be suitable for general display
       to a human user."/> 
      <min value="0"/> 
      <max value="1"/> 
      <base> 
        <path value="CodeSystem.concept.designation.use"/> 
        <min value="0"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="Coding"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
      <binding> 
        <extension url="http://hl7.org/fhir/StructureDefinition/elementdefinition-bindingName">
          <valueString value="ConceptDesignationUse"/> 
        </extension> 
        <strength value="extensible"/> 
        <description value="Details of how a designation would be used."/> 
        <valueSet value="http://hl7.org/fhir/ValueSet/designation-use"/> 
      </binding> 
    </element> 
    <element id="CodeSystem.concept.designation.value">
      <path value="CodeSystem.concept.designation.value"/> 
      <short value="The text value for this designation"/> 
      <definition value="The text value for this designation."/> 
      <min value="1"/> 
      <max value="1"/> 
      <base> 
        <path value="CodeSystem.concept.designation.value"/> 
        <min value="1"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="string"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
    </element> 
    <element id="CodeSystem.concept.property">
      <extension url="http://hl7.org/fhir/StructureDefinition/structuredefinition-explicit-type-name">
        <valueString value="ConceptProperty"/> 
      </extension> 
      <path value="CodeSystem.concept.property"/> 
      <short value="Property value for the concept"/> 
      <definition value="A property value for this concept."/> 
      <min value="0"/> 
      <max value="*"/> 
      <base> 
        <path value="CodeSystem.concept.property"/> 
        <min value="0"/> 
        <max value="*"/> 
      </base> 
      <type> 
        <code value="BackboneElement"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
    </element> 
    <element id="CodeSystem.concept.property.id">
      <path value="CodeSystem.concept.property.id"/> 
      <representation value="xmlAttr"/> 
      <short value="Unique id for inter-element referencing"/> 
      <definition value="Unique id for the element within a resource (for internal references). This may be any
       string value that does not contain spaces."/> 
      <min value="0"/> 
      <max value="1"/> 
      <base> 
        <path value="Element.id"/> 
        <min value="0"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <extension url="http://hl7.org/fhir/StructureDefinition/structuredefinition-fhir-type">
          <valueUrl value="string"/> 
        </extension> 
        <code value="http://hl7.org/fhirpath/System.String"/> 
      </type> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
      <mapping> 
        <identity value="rim"/> 
        <map value="n/a"/> 
      </mapping> 
    </element> 
    <element id="CodeSystem.concept.property.extension">
      <path value="CodeSystem.concept.property.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. 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
       can define an extension, there is a set of requirements that SHALL be met as part of the
       definition of the extension."/> 
      <comment 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="Element.extension"/> 
        <min value="0"/> 
        <max value="*"/> 
      </base> 
      <type> 
        <code value="Extension"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <constraint> 
        <key value="ext-1"/> 
        <severity value="error"/> 
        <human value="Must have either extensions or value[x], not both"/> 
        <expression value="extension.exists() != value.exists()"/> 
        <xpath value="exists(f:extension)!=exists(f:*[starts-with(local-name(.), &quot;value&quot;)])"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Extension"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
      <mapping> 
        <identity value="rim"/> 
        <map value="n/a"/> 
      </mapping> 
    </element> 
    <element id="CodeSystem.concept.property.modifierExtension">
      <path value="CodeSystem.concept.property.modifierExtension"/> 
      <short value="Extensions that cannot be ignored even if unrecognized"/> 
      <definition value="May be used to represent additional information that is not part of the basic definition
       of the element and that modifies the understanding of the element in which it is contained
       and/or the understanding of the containing element's descendants. Usually modifier elements
       provide negation or qualification. 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 can define an extension, there is a set of requirements that SHALL be
       met as part of the definition of the extension. Applications processing a resource are
       required to check for modifier extensions.

Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource
       (including cannot change the meaning of modifierExtension itself)."/> 
      <comment 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."/> 
      <requirements value="Modifier extensions allow for extensions that *cannot* be safely ignored to be clearly
       distinguished from the vast majority of extensions which can be safely ignored.  This
       promotes interoperability by eliminating the need for implementers to prohibit the presence
       of extensions. For further information, see the [definition of modifier extensions](http://hl7.org/f
      hir/extensibility.html#modifierExtension)."/> 
      <alias value="extensions"/> 
      <alias value="user content"/> 
      <alias value="modifiers"/> 
      <min value="0"/> 
      <max value="*"/> 
      <base> 
        <path value="BackboneElement.modifierExtension"/> 
        <min value="0"/> 
        <max value="*"/> 
      </base> 
      <type> 
        <code value="Extension"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <constraint> 
        <key value="ext-1"/> 
        <severity value="error"/> 
        <human value="Must have either extensions or value[x], not both"/> 
        <expression value="extension.exists() != value.exists()"/> 
        <xpath value="exists(f:extension)!=exists(f:*[starts-with(local-name(.), &quot;value&quot;)])"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Extension"/> 
      </constraint> 
      <isModifier value="true"/> 
      <isModifierReason value="Modifier extensions are expected to modify the meaning or interpretation of the element
       that contains them"/> 
      <isSummary value="true"/> 
      <mapping> 
        <identity value="rim"/> 
        <map value="N/A"/> 
      </mapping> 
    </element> 
    <element id="CodeSystem.concept.property.code">
      <path value="CodeSystem.concept.property.code"/> 
      <short value="Reference to CodeSystem.property.code"/> 
      <definition value="A code that is a reference to CodeSystem.property.code."/> 
      <min value="1"/> 
      <max value="1"/> 
      <base> 
        <path value="CodeSystem.concept.property.code"/> 
        <min value="1"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="code"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
    </element> 
    <element id="CodeSystem.concept.property.value[x]">
      <path value="CodeSystem.concept.property.value[x]"/> 
      <short value="Value of the property for this concept"/> 
      <definition value="The value of this property."/> 
      <min value="1"/> 
      <max value="1"/> 
      <base> 
        <path value="CodeSystem.concept.property.value[x]"/> 
        <min value="1"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="code"/> 
      </type> 
      <type> 
        <code value="Coding"/> 
      </type> 
      <type> 
        <code value="string"/> 
      </type> 
      <type> 
        <code value="integer"/> 
      </type> 
      <type> 
        <code value="boolean"/> 
      </type> 
      <type> 
        <code value="dateTime"/> 
      </type> 
      <type> 
        <code value="decimal"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
    </element> 
    <element id="CodeSystem.concept.concept">
      <path value="CodeSystem.concept.concept"/> 
      <short value="Child Concepts (is-a/contains/categorizes)"/> 
      <definition value="Defines children of a concept to produce a hierarchy of concepts. The nature of the relationships
       is variable (is-a/contains/categorizes) - see hierarchyMeaning."/> 
      <min value="0"/> 
      <max value="*"/> 
      <base> 
        <path value="CodeSystem.concept.concept"/> 
        <min value="0"/> 
        <max value="*"/> 
      </base> 
      <contentReference value="#CodeSystem.concept"/> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
    </element> 
  </snapshot> 
  <differential> 
    <element id="CodeSystem">
      <path value="CodeSystem"/> 
      <min value="1"/> 
      <max value="1"/> 
    </element> 
    <element id="CodeSystem.url">
      <path value="CodeSystem.url"/> 
      <min value="1"/> 
      <max value="1"/> 
      <type> 
        <code value="uri"/> 
      </type> 
    </element> 
    <element id="CodeSystem.version">
      <path value="CodeSystem.version"/> 
      <min value="1"/> 
      <max value="1"/> 
      <type> 
        <code value="string"/> 
      </type> 
    </element> 
    <element id="CodeSystem.name">
      <path value="CodeSystem.name"/> 
      <min value="1"/> 
      <max value="1"/> 
      <type> 
        <code value="string"/> 
      </type> 
    </element> 
    <element id="CodeSystem.status">
      <path value="CodeSystem.status"/> 
      <min value="1"/> 
      <max value="1"/> 
      <type> 
        <code value="code"/> 
      </type> 
      <mapping> 
        <identity value="rim"/> 
        <map value="N/A"/> 
      </mapping> 
    </element> 
    <element id="CodeSystem.experimental">
      <path value="CodeSystem.experimental"/> 
      <min value="1"/> 
      <max value="1"/> 
      <type> 
        <code value="boolean"/> 
      </type> 
    </element> 
    <element id="CodeSystem.publisher">
      <path value="CodeSystem.publisher"/> 
      <alias value="steward"/> 
      <min value="1"/> 
      <max value="1"/> 
      <type> 
        <code value="string"/> 
      </type> 
    </element> 
    <element id="CodeSystem.description">
      <path value="CodeSystem.description"/> 
      <alias value="scope"/> 
      <min value="1"/> 
      <max value="1"/> 
      <type> 
        <code value="markdown"/> 
      </type> 
      <mapping> 
        <identity value="rim"/> 
        <map value="N/A"/> 
      </mapping> 
    </element> 
    <element id="CodeSystem.caseSensitive">
      <path value="CodeSystem.caseSensitive"/> 
      <min value="0"/> 
      <max value="1"/> 
      <type> 
        <code value="boolean"/> 
      </type> 
    </element> 
    <element id="CodeSystem.concept">
      <path value="CodeSystem.concept"/> 
      <min value="1"/> 
      <max value="*"/> 
    </element> 
    <element id="CodeSystem.concept.code">
      <path value="CodeSystem.concept.code"/> 
      <min value="1"/> 
      <max value="1"/> 
      <type> 
        <code value="code"/> 
      </type> 
    </element> 
    <element id="CodeSystem.concept.display">
      <path value="CodeSystem.concept.display"/> 
      <min value="0"/> 
      <max value="1"/> 
      <type> 
        <code value="string"/> 
      </type> 
    </element> 
    <element id="CodeSystem.concept.definition">
      <path value="CodeSystem.concept.definition"/> 
      <min value="0"/> 
      <max value="1"/> 
      <type> 
        <code value="string"/> 
      </type> 
    </element> 
    <element id="CodeSystem.concept.concept">
      <path value="CodeSystem.concept.concept"/> 
      <min value="0"/> 
      <max value="*"/> 
      <contentReference value="#CodeSystem.concept"/> 
    </element> 
  </differential> 
</StructureDefinition>