This page is part of the FHIR Specification (v5.0.0: R5 - STU). This is the current published version. For a full list of available versions, see the Directory of published versions . Page versions: R5 R4B R4
StructureDefinition: ActualGroup - XML

FHIR Infrastructure Work Group
Maturity Level: 0
Trial Use
Use Context: Any
ActualGroup
<?xml version="1.0" encoding="UTF-8"?>

<StructureDefinition xmlns="http://hl7.org/fhir">
  <id value="actualgroup"/> 
  <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="0"/> 
  </extension> 
  <extension url="http://hl7.org/fhir/StructureDefinition/structuredefinition-wg">
    <valueCode value="fhir"/> 
  </extension> 
  <extension url="http://hl7.org/fhir/StructureDefinition/structuredefinition-standards-status">
    <valueCode value="trial-use"/> 
  </extension> 
  <url value="http://hl7.org/fhir/StructureDefinition/actualgroup"/> 
  <identifier> 
    <system value="urn:ietf:rfc:3986"/> 
    <value value="urn:oid:2.16.840.1.113883.4.642.5.1090"/> 
  </identifier> 
  <version value="5.0.0"/> 
  <name value="ActualGroup"/> 
  <title value="Actual  Group"/> 
  <status value="draft"/> 
  <experimental value="false"/> 
  <date value="2020-12-28T16:55:11+11:00"/> 
  <publisher value="HL7"/> 
  <description value="Enforces an enumerated group, rather than a definitional group"/> 
  <fhirVersion value="5.0.0"/> 
  <mapping> 
    <identity value="rim"/> 
    <uri value="http://hl7.org/v3"/> 
    <name value="RIM Mapping"/> 
  </mapping> 
  <mapping> 
    <identity value="interface"/> 
    <uri value="http://hl7.org/fhir/interface"/> 
    <name value="Interface Pattern"/> 
  </mapping> 
  <mapping> 
    <identity value="w5"/> 
    <uri value="http://hl7.org/fhir/fivews"/> 
    <name value="FiveWs Pattern Mapping"/> 
  </mapping> 
  <kind value="resource"/> 
  <abstract value="false"/> 
  <type value="Group"/> 
  <baseDefinition value="http://hl7.org/fhir/StructureDefinition/Group"/> 
  <derivation value="constraint"/> 
  <snapshot> 
    <element id="Group">
      <path value="Group"/> 
      <short value="Group of multiple entities"/> 
      <definition value="Represents a defined collection of entities that may be discussed or acted upon
       collectively but which are not expected to act collectively, and are not formally
       or legally recognized; i.e. a collection of entities that isn't an Organization."/> 
      <comment value="If both Group.characteristic and Group.member are present, then the members are
       the individuals who were found who met the characteristic.  It's possible that
       there might be other candidate members who meet the characteristic and aren't (yet)
       in the list.  All members SHALL have the listed characteristics."/> 
      <min value="1"/> 
      <max value="1"/> 
      <base> 
        <path value="Group"/> 
        <min value="0"/> 
        <max value="*"/> 
      </base> 
      <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()"/> 
        <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().ofTy
        pe(canonical) | %resource.descendants().ofType(uri) | %resource.descendants().ofType(url)))
         or descendants().where(reference = '#').exists() or descendants().where(ofType(canonical)
         = '#').exists() or descendants().where(ofType(canonical) = '#').exists()).not()).trace('unmat
        ched', id).empty()"/> 
        <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()"/> 
        <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()"/> 
        <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()"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/DomainResource"/> 
      </constraint> 
      <mustSupport value="false"/> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
      <mapping> 
        <identity value="rim"/> 
        <map value="Entity, Role, or Act,Entity[determinerCode=&quot;GRP&quot; or determinerCode=&quot;GRP_KIND&q
        uot;]"/> 
      </mapping> 
      <mapping> 
        <identity value="w5"/> 
        <map value="administrative.group"/> 
      </mapping> 
      <mapping> 
        <identity value="interface"/> 
        <map value="Participant"/> 
      </mapping> 
    </element> 
    <element id="Group.id">
      <path value="Group.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="Within the context of the FHIR RESTful interactions, the resource has an id except
       for cases like the create and conditional update. Otherwise, the use of the resouce
       id depends on the given use case."/> 
      <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="id"/> 
        </extension> 
        <code value="http://hl7.org/fhirpath/System.String"/> 
      </type> 
      <mustSupport value="false"/> 
      <isModifier value="false"/> 
      <isSummary value="true"/> 
    </element> 
    <element id="Group.meta">
      <path value="Group.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())"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <mustSupport value="false"/> 
      <isModifier value="false"/> 
      <isSummary value="true"/> 
    </element> 
    <element id="Group.implicitRules">
      <path value="Group.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 its 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())"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <mustSupport value="false"/> 
      <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 its meaning or interpretation"/> 
      <isSummary value="true"/> 
    </element> 
    <element id="Group.language">
      <path value="Group.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())"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <mustSupport value="false"/> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
      <binding> 
        <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="required"/> 
        <description value="IETF language tag for a human language"/> 
        <valueSet value="http://hl7.org/fhir/ValueSet/all-languages|5.0.0"/> 
        <additional> 
          <purpose value="starter"/> 
          <valueSet value="http://hl7.org/fhir/ValueSet/languages"/> 
        </additional> 
      </binding> 
    </element> 
    <element id="Group.text">
      <path value="Group.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 a 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> 
      <condition value="dom-6"/> 
      <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())"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <mustSupport value="false"/> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
      <mapping> 
        <identity value="rim"/> 
        <map value="Act.text?"/> 
      </mapping> 
    </element> 
    <element id="Group.contained">
      <path value="Group.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, nor can they have their
       own independent transaction scope. This is allowed to be a Parameters resource
       if and only if it is referenced by a resource that provides context/meaning."/> 
      <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> 
      <condition value="dom-2"/> 
      <condition value="dom-4"/> 
      <condition value="dom-3"/> 
      <condition value="dom-5"/> 
      <mustSupport value="false"/> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
      <mapping> 
        <identity value="rim"/> 
        <map value="N/A"/> 
      </mapping> 
    </element> 
    <element id="Group.extension">
      <path value="Group.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 managable, 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())"/> 
        <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()"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Extension"/> 
      </constraint> 
      <mustSupport value="false"/> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
      <mapping> 
        <identity value="rim"/> 
        <map value="N/A"/> 
      </mapping> 
    </element> 
    <element id="Group.modifierExtension">
      <path value="Group.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 managable, 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](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())"/> 
        <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()"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Extension"/> 
      </constraint> 
      <mustSupport value="false"/> 
      <isModifier value="true"/> 
      <isModifierReason value="Modifier extensions are expected to modify the meaning or interpretation of the
       resource that contains them"/> 
      <isSummary value="true"/> 
      <mapping> 
        <identity value="rim"/> 
        <map value="N/A"/> 
      </mapping> 
    </element> 
    <element id="Group.identifier">
      <path value="Group.identifier"/> 
      <short value="Business Identifier for this Group"/> 
      <definition value="Business identifiers assigned to this participant by one of the applications involved.
        These identifiers remain constant as the resource is updated and propagates from
       server to server."/> 
      <comment value="Note: This is a business identifier, not a resource identifier (see [discussion](resource.htm
      l#identifiers)).  It is best practice for the identifier to only appear on a single
       resource instance, however business practices may occasionally dictate that multiple
       resource instances with the same identifier can exist - possibly even with different
       resource types."/> 
      <requirements value="Allows identification of the group as it is known by various participating systems
       and in a way that remains consistent across servers."/> 
      <min value="0"/> 
      <max value="*"/> 
      <base> 
        <path value="Group.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())"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <mustSupport value="false"/> 
      <isModifier value="false"/> 
      <isSummary value="true"/> 
      <mapping> 
        <identity value="w5"/> 
        <map value="FiveWs.identifier"/> 
      </mapping> 
      <mapping> 
        <identity value="rim"/> 
        <map value="unique(./id[displayable=&quot;true&quot; and scope=&quot;OBJ&quot;])"/> 
      </mapping> 
      <mapping> 
        <identity value="interface"/> 
        <map value="Participant.identifier"/> 
      </mapping> 
    </element> 
    <element id="Group.active">
      <path value="Group.active"/> 
      <short value="Whether this group's record is in active use"/> 
      <definition value="Indicates whether the record for the group is available for use or is merely being
       retained for historical purposes."/> 
      <requirements value="Need to be able to mark a group record as not to be used because it was created
       in error or is otherwise no longer available (e.g. a herd that no longer exists)."/> 
      <min value="0"/> 
      <max value="1"/> 
      <base> 
        <path value="Group.active"/> 
        <min value="0"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="boolean"/> 
      </type> 
      <meaningWhenMissing value="This resource is generally assumed to be active if no value is provided for the
       active element"/> 
      <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())"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <mustSupport value="false"/> 
      <isModifier value="true"/> 
      <isModifierReason value="This element is labelled as a modifier because it is a status element that can
       indicate that a record should not be treated as valid"/> 
      <isSummary value="true"/> 
      <mapping> 
        <identity value="w5"/> 
        <map value="FiveWs.status"/> 
      </mapping> 
      <mapping> 
        <identity value="rim"/> 
        <map value="./statusCode"/> 
      </mapping> 
      <mapping> 
        <identity value="interface"/> 
        <map value="Participant.active"/> 
      </mapping> 
    </element> 
    <element id="Group.type">
      <path value="Group.type"/> 
      <short value="person | animal | practitioner | device | careteam | healthcareservice | location
       | organization | relatedperson | specimen"/> 
      <definition value="Identifies the broad classification of the kind of resources the group includes."/> 
      <comment value="Group members SHALL be of the appropriate resource type (Patient for person or
       animal; or Practitioner, PractitionerRole, Device, CareTeam, HealthcareService,
       Location, Organization, RelatedPerson, or Specimen for the other types.), or a
       Group of the resources of the appropriate type."/> 
      <requirements value="Identifies what type of resources the group is made up of."/> 
      <min value="1"/> 
      <max value="1"/> 
      <base> 
        <path value="Group.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())"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <mustSupport value="false"/> 
      <isModifier value="false"/> 
      <isSummary value="true"/> 
      <binding> 
        <extension url="http://hl7.org/fhir/StructureDefinition/elementdefinition-bindingName">
          <valueString value="GroupType"/> 
        </extension> 
        <strength value="required"/> 
        <description value="Types of resources that are part of group."/> 
        <valueSet value="http://hl7.org/fhir/ValueSet/group-type|5.0.0"/> 
      </binding> 
      <mapping> 
        <identity value="w5"/> 
        <map value="FiveWs.class"/> 
      </mapping> 
      <mapping> 
        <identity value="rim"/> 
        <map value="person: ./classCode=&quot;PSN&quot;  animal: ./classCode=&quot;ANM&quot;  device:
         ./classCode=&quot;DEV&quot;  medication: ./classCode=&quot;MMAT&quot; and ./playedRole[isNorm
        alRole() and classCode=&quot;THER&quot;]  food: ./classCode=&quot;FOOD&quot;"/> 
      </mapping> 
    </element> 
    <element id="Group.membership">
      <path value="Group.membership"/> 
      <short value="definitional | enumerated"/> 
      <definition value="Basis for membership in the Group:

* 'definitional': The Group.characteristics specified are both necessary and sufficient
       to determine membership. All entities that meet the criteria are considered to
       be members of the group, whether referenced by the group or not. If members are
       present, they are individuals that happen to be known as meeting the Group.characteristics.
       The list cannot be presumed to be complete.
* 'enumerated': The Group.characteristics are necessary but not sufficient to determine
       membership. Membership is determined by being listed as one of the Group.member."/> 
      <requirements value="There are use-cases for groups that define specific collections of individuals,
       and other groups that define &quot;types&quot; of intended individuals.  The requirements
       for both kinds of groups are similar, so we use a single resource, distinguished
       by this element."/> 
      <min value="1"/> 
      <max value="1"/> 
      <base> 
        <path value="Group.membership"/> 
        <min value="1"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="code"/> 
      </type> 
      <fixedCode value="enumerated"/> 
      <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())"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <mustSupport value="false"/> 
      <isModifier value="false"/> 
      <isSummary value="true"/> 
      <binding> 
        <strength value="required"/> 
        <description value="The basis for membership in a group"/> 
        <valueSet value="http://hl7.org/fhir/ValueSet/group-membership-basis|5.0.0"/> 
      </binding> 
    </element> 
    <element id="Group.code">
      <path value="Group.code"/> 
      <short value="Kind of Group members"/> 
      <definition value="Provides a specific type of resource the group includes; e.g. &quot;cow&quot;,
       &quot;syringe&quot;, etc."/> 
      <comment value="This would generally be omitted for Person resources."/> 
      <min value="0"/> 
      <max value="1"/> 
      <base> 
        <path value="Group.code"/> 
        <min value="0"/> 
        <max value="1"/> 
      </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())"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <mustSupport value="false"/> 
      <isModifier value="false"/> 
      <isSummary value="true"/> 
      <binding> 
        <extension url="http://hl7.org/fhir/StructureDefinition/elementdefinition-bindingName">
          <valueString value="GroupKind"/> 
        </extension> 
        <strength value="example"/> 
        <description value="Kind of particular resource; e.g. cow, syringe, lake, etc."/> 
      </binding> 
      <mapping> 
        <identity value="w5"/> 
        <map value="FiveWs.what[x]"/> 
      </mapping> 
      <mapping> 
        <identity value="rim"/> 
        <map value="./code"/> 
      </mapping> 
    </element> 
    <element id="Group.name">
      <path value="Group.name"/> 
      <short value="Label for Group"/> 
      <definition value="A label assigned to the group for human identification and communication."/> 
      <requirements value="Used to identify the group in human communication."/> 
      <min value="0"/> 
      <max value="1"/> 
      <base> 
        <path value="Group.name"/> 
        <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())"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <mustSupport value="false"/> 
      <isModifier value="false"/> 
      <isSummary value="true"/> 
      <mapping> 
        <identity value="rim"/> 
        <map value="./name[type=&quot;ST&quot;]"/> 
      </mapping> 
      <mapping> 
        <identity value="interface"/> 
        <map value="Participant.name"/> 
      </mapping> 
    </element> 
    <element id="Group.description">
      <path value="Group.description"/> 
      <short value="Natural language description of the group"/> 
      <definition value="Explanation of what the group represents and how it is intended to be used."/> 
      <min value="0"/> 
      <max value="1"/> 
      <base> 
        <path value="Group.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())"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <mustSupport value="false"/> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
    </element> 
    <element id="Group.quantity">
      <path value="Group.quantity"/> 
      <short value="Number of members"/> 
      <definition value="A count of the number of resource instances that are part of the group."/> 
      <comment value="Note that the quantity may be less than the number of members if some of the members
       are not active."/> 
      <requirements value="Group size is a common defining characteristic."/> 
      <min value="0"/> 
      <max value="1"/> 
      <base> 
        <path value="Group.quantity"/> 
        <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())"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <mustSupport value="false"/> 
      <isModifier value="false"/> 
      <isSummary value="true"/> 
      <mapping> 
        <identity value="rim"/> 
        <map value="./quantity"/> 
      </mapping> 
    </element> 
    <element id="Group.managingEntity">
      <path value="Group.managingEntity"/> 
      <short value="Entity that is the custodian of the Group's definition"/> 
      <definition value="Entity responsible for defining and maintaining Group characteristics and/or registered
       members."/> 
      <comment value="This does not strictly align with ownership of a herd or flock, but may suffice
       to represent that relationship in simple cases. More complex cases will require
       an extension."/> 
      <min value="0"/> 
      <max value="1"/> 
      <base> 
        <path value="Group.managingEntity"/> 
        <min value="0"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="Reference"/> 
        <targetProfile value="http://hl7.org/fhir/StructureDefinition/Organization"/> 
        <targetProfile value="http://hl7.org/fhir/StructureDefinition/RelatedPerson"/> 
        <targetProfile value="http://hl7.org/fhir/StructureDefinition/Practitioner"/> 
        <targetProfile value="http://hl7.org/fhir/StructureDefinition/PractitionerRole"/> 
      </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())"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <mustSupport value="false"/> 
      <isModifier value="false"/> 
      <isSummary value="true"/> 
      <mapping> 
        <identity value="w5"/> 
        <map value="FiveWs.witness"/> 
      </mapping> 
    </element> 
    <element id="Group.characteristic">
      <path value="Group.characteristic"/> 
      <short value="Include / Exclude group members by Trait"/> 
      <definition value="Identifies traits whose presence r absence is shared by members of the group."/> 
      <comment value="All the identified characteristics must be true for an entity to a member of the
       group."/> 
      <requirements value="Needs to be a generic mechanism for identifying what individuals can be part of
       a group."/> 
      <min value="0"/> 
      <max value="*"/> 
      <base> 
        <path value="Group.characteristic"/> 
        <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())"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <mustSupport value="false"/> 
      <isModifier value="false"/> 
      <isSummary value="true"/> 
      <mapping> 
        <identity value="rim"/> 
        <map value="./playedRole[isNormalRole()]/participation[isNormalParticipation() and typeCode=&quot;SBJ&quo
        t;]/act[isNormalAct and classCode=&quot;OBS&quot; and moodCode=&quot;EVN&quot;]"/> 
      </mapping> 
    </element> 
    <element id="Group.characteristic.id">
      <path value="Group.characteristic.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> 
      <condition value="ele-1"/> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
      <mapping> 
        <identity value="rim"/> 
        <map value="n/a"/> 
      </mapping> 
    </element> 
    <element id="Group.characteristic.extension">
      <path value="Group.characteristic.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 managable, 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())"/> 
        <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()"/> 
        <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="Group.characteristic.modifierExtension">
      <path value="Group.characteristic.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 managable, 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](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())"/> 
        <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()"/> 
        <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="Group.characteristic.code">
      <path value="Group.characteristic.code"/> 
      <short value="Kind of characteristic"/> 
      <definition value="A code that identifies the kind of trait being asserted."/> 
      <requirements value="Need a formal way of identifying the characteristic being described."/> 
      <min value="1"/> 
      <max value="1"/> 
      <base> 
        <path value="Group.characteristic.code"/> 
        <min value="1"/> 
        <max value="1"/> 
      </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())"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <mustSupport value="false"/> 
      <isModifier value="false"/> 
      <isSummary value="true"/> 
      <binding> 
        <extension url="http://hl7.org/fhir/StructureDefinition/elementdefinition-bindingName">
          <valueString value="GroupCharacteristicKind"/> 
        </extension> 
        <strength value="example"/> 
        <description value="List of characteristics used to describe group members; e.g. gender, age, owner,
         location, etc."/> 
      </binding> 
      <mapping> 
        <identity value="rim"/> 
        <map value="./code"/> 
      </mapping> 
    </element> 
    <element id="Group.characteristic.value[x]">
      <path value="Group.characteristic.value[x]"/> 
      <short value="Value held by characteristic"/> 
      <definition value="The value of the trait that holds (or does not hold - see 'exclude') for members
       of the group."/> 
      <comment value="For Range, it means members of the group have a value that falls somewhere within
       the specified range."/> 
      <requirements value="The value of the characteristic is what determines group membership."/> 
      <min value="1"/> 
      <max value="1"/> 
      <base> 
        <path value="Group.characteristic.value[x]"/> 
        <min value="1"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="CodeableConcept"/> 
      </type> 
      <type> 
        <code value="boolean"/> 
      </type> 
      <type> 
        <code value="Quantity"/> 
      </type> 
      <type> 
        <code value="Range"/> 
      </type> 
      <type> 
        <code value="Reference"/> 
      </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())"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <mustSupport value="false"/> 
      <isModifier value="false"/> 
      <isSummary value="true"/> 
      <binding> 
        <extension url="http://hl7.org/fhir/StructureDefinition/elementdefinition-bindingName">
          <valueString value="GroupCharacteristicValue"/> 
        </extension> 
        <strength value="example"/> 
        <description value="Value of descriptive member characteristic; e.g. red, male, pneumonia, Caucasian,
         etc."/> 
      </binding> 
      <mapping> 
        <identity value="rim"/> 
        <map value="./value"/> 
      </mapping> 
    </element> 
    <element id="Group.characteristic.exclude">
      <path value="Group.characteristic.exclude"/> 
      <short value="Group includes or excludes"/> 
      <definition value="If true, indicates the characteristic is one that is NOT held by members of the
       group."/> 
      <comment value="This is labeled as &quot;Is Modifier&quot; because applications cannot wrongly
       include excluded members as included or vice versa."/> 
      <requirements value="Sometimes group membership is determined by characteristics not possessed."/> 
      <min value="1"/> 
      <max value="1"/> 
      <base> 
        <path value="Group.characteristic.exclude"/> 
        <min value="1"/> 
        <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())"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <mustSupport value="false"/> 
      <isModifier value="false"/> 
      <isSummary value="true"/> 
      <mapping> 
        <identity value="rim"/> 
        <map value="./valueNegationInd"/> 
      </mapping> 
    </element> 
    <element id="Group.characteristic.period">
      <path value="Group.characteristic.period"/> 
      <short value="Period over which characteristic is tested"/> 
      <definition value="The period over which the characteristic is tested; e.g. the patient had an operation
       during the month of June."/> 
      <min value="0"/> 
      <max value="1"/> 
      <base> 
        <path value="Group.characteristic.period"/> 
        <min value="0"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="Period"/> 
      </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())"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <mustSupport value="false"/> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
    </element> 
    <element id="Group.member">
      <path value="Group.member"/> 
      <short value="Who or what is in group"/> 
      <definition value="Identifies the resource instances that are members of the group."/> 
      <requirements value="Often the only thing of interest about a group is &quot;who's in it&quot;."/> 
      <min value="0"/> 
      <max value="*"/> 
      <base> 
        <path value="Group.member"/> 
        <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())"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <mustSupport value="false"/> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
      <mapping> 
        <identity value="w5"/> 
        <map value="FiveWs.subject[x]"/> 
      </mapping> 
      <mapping> 
        <identity value="rim"/> 
        <map value="./scopedRole[isNormalRole() and classCode=&quot;MBR&quot;]/player"/> 
      </mapping> 
    </element> 
    <element id="Group.member.id">
      <path value="Group.member.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> 
      <condition value="ele-1"/> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
      <mapping> 
        <identity value="rim"/> 
        <map value="n/a"/> 
      </mapping> 
    </element> 
    <element id="Group.member.extension">
      <path value="Group.member.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 managable, 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())"/> 
        <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()"/> 
        <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="Group.member.modifierExtension">
      <path value="Group.member.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 managable, 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](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())"/> 
        <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()"/> 
        <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="Group.member.entity">
      <path value="Group.member.entity"/> 
      <short value="Reference to the group member"/> 
      <definition value="A reference to the entity that is a member of the group. Must be consistent with
       Group.type. If the entity is another group, then the type must be the same."/> 
      <min value="1"/> 
      <max value="1"/> 
      <base> 
        <path value="Group.member.entity"/> 
        <min value="1"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="Reference"/> 
        <targetProfile value="http://hl7.org/fhir/StructureDefinition/CareTeam"/> 
        <targetProfile value="http://hl7.org/fhir/StructureDefinition/Device"/> 
        <targetProfile value="http://hl7.org/fhir/StructureDefinition/Group"/> 
        <targetProfile value="http://hl7.org/fhir/StructureDefinition/HealthcareService"/> 
        <targetProfile value="http://hl7.org/fhir/StructureDefinition/Location"/> 
        <targetProfile value="http://hl7.org/fhir/StructureDefinition/Organization"/> 
        <targetProfile value="http://hl7.org/fhir/StructureDefinition/Patient"/> 
        <targetProfile value="http://hl7.org/fhir/StructureDefinition/Practitioner"/> 
        <targetProfile value="http://hl7.org/fhir/StructureDefinition/PractitionerRole"/> 
        <targetProfile value="http://hl7.org/fhir/StructureDefinition/RelatedPerson"/> 
        <targetProfile value="http://hl7.org/fhir/StructureDefinition/Specimen"/> 
      </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())"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <mustSupport value="false"/> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
    </element> 
    <element id="Group.member.period">
      <path value="Group.member.period"/> 
      <short value="Period member belonged to the group"/> 
      <definition value="The period that the member was in the group, if known."/> 
      <requirements value="Need to track who was in a group at a  particular time."/> 
      <min value="0"/> 
      <max value="1"/> 
      <base> 
        <path value="Group.member.period"/> 
        <min value="0"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="Period"/> 
      </type> 
      <meaningWhenMissing value="The member is in the group at this time"/> 
      <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())"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <mustSupport value="false"/> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
    </element> 
    <element id="Group.member.inactive">
      <path value="Group.member.inactive"/> 
      <short value="If member is no longer in group"/> 
      <definition value="A flag to indicate that the member is no longer in the group, but previously may
       have been a member."/> 
      <requirements value="Sometimes you don't know when someone stopped being in a group, but not when."/> 
      <min value="0"/> 
      <max value="1"/> 
      <base> 
        <path value="Group.member.inactive"/> 
        <min value="0"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="boolean"/> 
      </type> 
      <meaningWhenMissing value="Members are considered active unless explicitly specified otherwise"/> 
      <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())"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <mustSupport value="false"/> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
    </element> 
  </snapshot> 
  <differential> 
    <element id="Group">
      <path value="Group"/> 
      <min value="1"/> 
      <max value="1"/> 
    </element> 
    <element id="Group.membership">
      <path value="Group.membership"/> 
      <min value="1"/> 
      <max value="1"/> 
      <type> 
        <code value="code"/> 
      </type> 
      <fixedCode value="enumerated"/> 
    </element> 
  </differential> 
</StructureDefinition>