Da Vinci Clinical Data Exchange (CDex)
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Da Vinci Clinical Data Exchange (CDex), published by HL7 International / Payer/Provider Information Exchange Work Group. This guide is not an authorized publication; it is the continuous build for version 2.1.0-preview built by the FHIR (HL7® FHIR® Standard) CI Build. This version is based on the current content of https://github.com/HL7/davinci-ecdx/ and changes regularly. See the Directory of published versions

Data Type Profile: CDexSignature - Detailed Descriptions

Page standards status: Trial-use Maturity Level: 2

Definitions for the cdex-signature data type profile.

Guidance on how to interpret the contents of this table can be found here

0. Signature
Definition

A JWS digital signature along with supporting context.

ShortJWS Digital Signature
Invariantscdex-13: The signature element must have either reference to the signer or the signer's identifier and name. (who.reference.exists() or (who.identifier.exists() and who.display.exists()))
2. Signature.type
Control1..?
Must Supporttrue
SlicingThis element introduces a set of slices on Signature.type. The slices are unordered and Open, and can be differentiated using the following discriminators:
  • pattern @ $this
  • 4. Signature.type:verify
    Slice Nameverify
    ShortVerification Signature
    Control1..1
    Must Supporttrue
    Pattern Value{
      "system" : "urn:iso-astm:E1762-95:2013",
      "code" : "1.2.840.10065.1.12.1.5",
      "display" : "Verification Signature"
    }
    6. Signature.when
    Must Supporttrue
    8. Signature.who
    ShortOrganization or practitioner who signed the Bundle
    TypeReference(US Core Practitioner Profile, US Core Organization Profile, US Core PractitionerRole Profile)
    Must Supporttrue
    Must Support TypesReference(US Core Practitioner Profile, US Core Organization Profile)
    10. Signature.who.reference
    Must Supporttrue
    12. Signature.who.identifier
    Definition

    NPI or Tax ID representing the Provider or Organization

    ShortNPI or US Tax ID
    NoteThis is a business identifier, not a resource identifier (see discussion)
    Must Supporttrue
    14. Signature.who.identifier.type
    Control1..?
    BindingThe codes SHALL be taken from CDex Identifier Types Value Set
    (required to http://hl7.org/fhir/us/davinci-cdex/ValueSet/cdex-identifier-types)
    Must Supporttrue
    16. Signature.who.identifier.value
    Control1..?
    Must Supporttrue
    18. Signature.who.display
    Must Supporttrue
    20. Signature.data
    Shortbase64 encoded JWS-Signature
    Control1..?
    Must Supporttrue

    Guidance on how to interpret the contents of this table can be found here

    0. Signature
    Definition

    A JWS digital signature along with supporting context.


    A signature along with supporting context. The signature may be a digital signature that is cryptographic in nature, or some other signature acceptable to the domain. This other signature may be as simple as a graphical image representing a hand-written signature, or a signature ceremony Different signature approaches have different utilities.

    ShortJWS Digital SignatureA Signature - XML DigSig, JWS, Graphical image of signature, etc.
    Comments

    The elements of the Signature Resource are for ease of access of these elements. For digital signatures (Xml DigSig, JWS), the non-repudiation proof comes from the Signature validation, which includes validation of the referenced objects (e.g. Resources) (a.k.a., Content) in the XML-Signature Detached form.

    Control0..*
    This element is affected by the following invariants: ele-1
    Is Modifierfalse
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    cdex-13: The signature element must have either reference to the signer or the signer's identifier and name. (who.reference.exists() or (who.identifier.exists() and who.display.exists()))
    2. Signature.type
    Definition

    An indication of the reason that the entity signed this document. This may be explicitly included as part of the signature information and can be used when determining accountability for various actions concerning the document.

    ShortIndication of the reason the entity signed the object(s)
    Comments

    Examples include attesting to: authorship, correct transcription, and witness of specific event. Also known as a "Commitment Type Indication".

    Control1..*
    BindingThe codes SHOULD be taken from SignatureTypeCodeshttp://hl7.org/fhir/ValueSet/signature-type
    (preferred to http://hl7.org/fhir/ValueSet/signature-type)

    An indication of the reason that an entity signed the object.

    TypeCoding
    Is Modifierfalse
    Must Supporttrue
    Summarytrue
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    SlicingThis element introduces a set of slices on Signature.type. The slices are unordered and Open, and can be differentiated using the following discriminators:
    • pattern @ $this
    • 4. Signature.type:verify
      Slice Nameverify
      Definition

      An indication of the reason that the entity signed this document. This may be explicitly included as part of the signature information and can be used when determining accountability for various actions concerning the document.

      ShortVerification SignatureIndication of the reason the entity signed the object(s)
      Comments

      Examples include attesting to: authorship, correct transcription, and witness of specific event. Also known as a "Commitment Type Indication".

      Control1..1*
      BindingThe codes SHOULD be taken from SignatureTypeCodeshttp://hl7.org/fhir/ValueSet/signature-type
      (preferred to http://hl7.org/fhir/ValueSet/signature-type)

      An indication of the reason that an entity signed the object.

      TypeCoding
      Is Modifierfalse
      Must Supporttrue
      Summarytrue
      Pattern Value{
        "system" : "urn:iso-astm:E1762-95:2013",
        "code" : "1.2.840.10065.1.12.1.5",
        "display" : "Verification Signature"
      }
      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      6. Signature.when
      Definition

      When the digital signature was signed.

      ShortWhen the signature was created
      Comments

      This should agree with the information in the signature.

      Control1..1
      Typeinstant
      Is Modifierfalse
      Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
      Must Supporttrue
      Summarytrue
      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      8. Signature.who
      Definition

      A reference to an application-usable description of the identity that signed (e.g. the signature used their private key).

      ShortOrganization or practitioner who signed the BundleWho signed
      Comments

      This should agree with the information in the signature.

      Control1..1
      TypeReference(US Core Practitioner Profile, US Core Organization Profile, US Core PractitionerRole Profile, Practitioner, PractitionerRole, RelatedPerson, Patient, Device, Organization)
      Is Modifierfalse
      Must Supporttrue
      Must Support TypesReference(US Core Practitioner Profile, US Core Organization Profile)
      Summarytrue
      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      10. Signature.who.reference
      Definition

      A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources.

      ShortLiteral reference, Relative, internal or absolute URL
      Comments

      Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server.

      Control0..1
      This element is affected by the following invariants: ref-1, cdex-13
      Typestring
      Is Modifierfalse
      Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
      Must Supporttrue
      Summarytrue
      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      12. Signature.who.identifier
      Definition

      NPI or Tax ID representing the Provider or Organization


      An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference.

      ShortNPI or US Tax IDLogical reference, when literal reference is not known
      Comments

      When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy.

      When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference

      Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it.

      Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any).

      NoteThis is a business identifier, not a resource identifier (see discussion)
      Control0..1
      This element is affected by the following invariants: cdex-13
      TypeIdentifier
      Is Modifierfalse
      Must Supporttrue
      Summarytrue
      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      14. Signature.who.identifier.use
      Definition

      The purpose of this identifier.

      Shortusual | official | temp | secondary | old (If known)
      Comments

      Applications can assume that an identifier is permanent unless it explicitly says that it is temporary.

      Control0..1
      BindingThe codes SHALL be taken from IdentifierUsehttp://hl7.org/fhir/ValueSet/identifier-use|4.0.1
      (required to http://hl7.org/fhir/ValueSet/identifier-use|4.0.1)

      Identifies the purpose for this identifier, if known .

      Typecode
      Is Modifiertrue because This is labeled as "Is Modifier" because applications should not mistake a temporary id for a permanent one.
      Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
      Summarytrue
      Requirements

      Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers.

      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      16. Signature.who.identifier.type
      Definition

      A coded type for the identifier that can be used to determine which identifier to use for a specific purpose.

      ShortDescription of identifier
      Comments

      This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type.

      Control10..1
      BindingThe codes SHALL be taken from Unless not suitable, these codes SHALL be taken from CDex Identifier Types Value Sethttp://hl7.org/fhir/ValueSet/identifier-type
      (required to http://hl7.org/fhir/us/davinci-cdex/ValueSet/cdex-identifier-types)
      TypeCodeableConcept
      Is Modifierfalse
      Must Supporttrue
      Summarytrue
      Requirements

      Allows users to make use of identifiers when the identifier system is not known.

      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      18. Signature.who.identifier.value
      Definition

      The portion of the identifier typically relevant to the user and which is unique within the context of the system.

      ShortThe value that is unique
      Comments

      If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe.

      Control10..1
      Typestring
      Is Modifierfalse
      Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
      Must Supporttrue
      Summarytrue
      Example<br/><b>General</b>:123456
      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      20. Signature.who.display
      Definition

      Plain text narrative that identifies the resource in addition to the resource reference.

      ShortText alternative for the resource
      Comments

      This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it.

      Control0..1
      This element is affected by the following invariants: cdex-13
      Typestring
      Is Modifierfalse
      Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
      Must Supporttrue
      Summarytrue
      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      22. Signature.data
      Definition

      The base64 encoding of the Signature content. When signature is not recorded electronically this element would be empty.

      Shortbase64 encoded JWS-SignatureThe actual signature content (XML DigSig. JWS, picture, etc.)
      Comments

      Where the signature type is an XML DigSig, the signed content is a FHIR Resource(s), the signature is of the XML form of the Resource(s) using XML-Signature (XMLDIG) "Detached Signature" form.

      Control10..1
      Typebase64Binary
      Is Modifierfalse
      Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
      Must Supporttrue
      Summaryfalse
      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))

      Guidance on how to interpret the contents of this table can be found here

      0. Signature
      Definition

      A JWS digital signature along with supporting context.

      ShortJWS Digital Signature
      Comments

      The elements of the Signature Resource are for ease of access of these elements. For digital signatures (Xml DigSig, JWS), the non-repudiation proof comes from the Signature validation, which includes validation of the referenced objects (e.g. Resources) (a.k.a., Content) in the XML-Signature Detached form.

      Control0..*
      This element is affected by the following invariants: ele-1
      Is Modifierfalse
      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      cdex-13: The signature element must have either reference to the signer or the signer's identifier and name. (who.reference.exists() or (who.identifier.exists() and who.display.exists()))
      2. Signature.id
      Definition

      Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

      ShortUnique id for inter-element referencing
      Control0..1
      Typestring
      Is Modifierfalse
      XML FormatIn the XML format, this property is represented as an attribute.
      Summaryfalse
      4. Signature.extension
      Definition

      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.

      ShortAdditional content defined by implementations
      Comments

      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.

      Control0..*
      TypeExtension
      Is Modifierfalse
      Summaryfalse
      Alternate Namesextensions, user content
      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
      SlicingThis element introduces a set of slices on Signature.extension. The slices are unordered and Open, and can be differentiated using the following discriminators:
      • value @ url
      • 6. Signature.type
        Definition

        An indication of the reason that the entity signed this document. This may be explicitly included as part of the signature information and can be used when determining accountability for various actions concerning the document.

        ShortIndication of the reason the entity signed the object(s)
        Comments

        Examples include attesting to: authorship, correct transcription, and witness of specific event. Also known as a "Commitment Type Indication".

        Control1..*
        BindingThe codes SHOULD be taken from SignatureTypeCodes
        (preferred to http://hl7.org/fhir/ValueSet/signature-type)

        An indication of the reason that an entity signed the object.

        TypeCoding
        Is Modifierfalse
        Must Supporttrue
        Summarytrue
        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
        SlicingThis element introduces a set of slices on Signature.type. The slices are unordered and Open, and can be differentiated using the following discriminators:
        • pattern @ $this
        • 8. Signature.type:verify
          Slice Nameverify
          Definition

          An indication of the reason that the entity signed this document. This may be explicitly included as part of the signature information and can be used when determining accountability for various actions concerning the document.

          ShortVerification Signature
          Comments

          Examples include attesting to: authorship, correct transcription, and witness of specific event. Also known as a "Commitment Type Indication".

          Control1..1
          BindingThe codes SHOULD be taken from SignatureTypeCodes
          (preferred to http://hl7.org/fhir/ValueSet/signature-type)

          An indication of the reason that an entity signed the object.

          TypeCoding
          Is Modifierfalse
          Must Supporttrue
          Summarytrue
          Pattern Value{
            "system" : "urn:iso-astm:E1762-95:2013",
            "code" : "1.2.840.10065.1.12.1.5",
            "display" : "Verification Signature"
          }
          Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
          10. Signature.when
          Definition

          When the digital signature was signed.

          ShortWhen the signature was created
          Comments

          This should agree with the information in the signature.

          Control1..1
          Typeinstant
          Is Modifierfalse
          Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
          Must Supporttrue
          Summarytrue
          Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
          12. Signature.who
          Definition

          A reference to an application-usable description of the identity that signed (e.g. the signature used their private key).

          ShortOrganization or practitioner who signed the Bundle
          Comments

          This should agree with the information in the signature.

          Control1..1
          TypeReference(US Core Practitioner Profile, US Core Organization Profile, US Core PractitionerRole Profile)
          Is Modifierfalse
          Must Supporttrue
          Must Support TypesReference(US Core Practitioner Profile, US Core Organization Profile)
          Summarytrue
          Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
          14. Signature.who.id
          Definition

          Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

          ShortUnique id for inter-element referencing
          Control0..1
          Typestring
          Is Modifierfalse
          XML FormatIn the XML format, this property is represented as an attribute.
          Summaryfalse
          16. Signature.who.extension
          Definition

          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.

          ShortAdditional content defined by implementations
          Comments

          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.

          Control0..*
          TypeExtension
          Is Modifierfalse
          Summaryfalse
          Alternate Namesextensions, user content
          Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
          ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
          SlicingThis element introduces a set of slices on Signature.who.extension. The slices are unordered and Open, and can be differentiated using the following discriminators:
          • value @ url
          • 18. Signature.who.reference
            Definition

            A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources.

            ShortLiteral reference, Relative, internal or absolute URL
            Comments

            Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server.

            Control0..1
            This element is affected by the following invariants: ref-1, cdex-13
            Typestring
            Is Modifierfalse
            Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
            Must Supporttrue
            Summarytrue
            Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
            20. Signature.who.type
            Definition

            The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent.

            The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources).

            ShortType the reference refers to (e.g. "Patient")
            Comments

            This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified.

            Control0..1
            BindingUnless not suitable, these codes SHALL be taken from ResourceType
            (extensible to http://hl7.org/fhir/ValueSet/resource-types)

            Aa resource (or, for logical models, the URI of the logical model).

            Typeuri
            Is Modifierfalse
            Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
            Summarytrue
            Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
            22. Signature.who.identifier
            Definition

            NPI or Tax ID representing the Provider or Organization

            ShortNPI or US Tax ID
            Comments

            When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy.

            When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference

            Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it.

            Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any).

            NoteThis is a business identifier, not a resource identifier (see discussion)
            Control0..1
            This element is affected by the following invariants: cdex-13
            TypeIdentifier
            Is Modifierfalse
            Must Supporttrue
            Summarytrue
            Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
            24. Signature.who.identifier.id
            Definition

            Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

            ShortUnique id for inter-element referencing
            Control0..1
            Typestring
            Is Modifierfalse
            XML FormatIn the XML format, this property is represented as an attribute.
            Summaryfalse
            26. Signature.who.identifier.extension
            Definition

            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.

            ShortAdditional content defined by implementations
            Comments

            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.

            Control0..*
            TypeExtension
            Is Modifierfalse
            Summaryfalse
            Alternate Namesextensions, user content
            Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
            ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
            SlicingThis element introduces a set of slices on Signature.who.identifier.extension. The slices are unordered and Open, and can be differentiated using the following discriminators:
            • value @ url
            • 28. Signature.who.identifier.use
              Definition

              The purpose of this identifier.

              Shortusual | official | temp | secondary | old (If known)
              Comments

              Applications can assume that an identifier is permanent unless it explicitly says that it is temporary.

              Control0..1
              BindingThe codes SHALL be taken from IdentifierUse
              (required to http://hl7.org/fhir/ValueSet/identifier-use|4.0.1)

              Identifies the purpose for this identifier, if known .

              Typecode
              Is Modifiertrue because This is labeled as "Is Modifier" because applications should not mistake a temporary id for a permanent one.
              Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
              Summarytrue
              Requirements

              Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers.

              Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
              30. Signature.who.identifier.type
              Definition

              A coded type for the identifier that can be used to determine which identifier to use for a specific purpose.

              ShortDescription of identifier
              Comments

              This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type.

              Control1..1
              BindingThe codes SHALL be taken from CDex Identifier Types Value Set
              (required to http://hl7.org/fhir/us/davinci-cdex/ValueSet/cdex-identifier-types)
              TypeCodeableConcept
              Is Modifierfalse
              Must Supporttrue
              Summarytrue
              Requirements

              Allows users to make use of identifiers when the identifier system is not known.

              Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
              32. Signature.who.identifier.system
              Definition

              Establishes the namespace for the value - that is, a URL that describes a set values that are unique.

              ShortThe namespace for the identifier value
              Comments

              Identifier.system is always case sensitive.

              Control0..1
              Typeuri
              Is Modifierfalse
              Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
              Summarytrue
              Requirements

              There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers.

              Example<br/><b>General</b>:http://www.acme.com/identifiers/patient
              Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
              34. Signature.who.identifier.value
              Definition

              The portion of the identifier typically relevant to the user and which is unique within the context of the system.

              ShortThe value that is unique
              Comments

              If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe.

              Control1..1
              Typestring
              Is Modifierfalse
              Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
              Must Supporttrue
              Summarytrue
              Example<br/><b>General</b>:123456
              Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
              36. Signature.who.identifier.period
              Definition

              Time period during which identifier is/was valid for use.

              ShortTime period when id is/was valid for use
              Control0..1
              TypePeriod
              Is Modifierfalse
              Summarytrue
              Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
              38. Signature.who.identifier.assigner
              Definition

              Organization that issued/manages the identifier.

              ShortOrganization that issued id (may be just text)
              Comments

              The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization.

              Control0..1
              TypeReference(Organization)
              Is Modifierfalse
              Summarytrue
              Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
              40. Signature.who.display
              Definition

              Plain text narrative that identifies the resource in addition to the resource reference.

              ShortText alternative for the resource
              Comments

              This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it.

              Control0..1
              This element is affected by the following invariants: cdex-13
              Typestring
              Is Modifierfalse
              Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
              Must Supporttrue
              Summarytrue
              Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
              42. Signature.onBehalfOf
              Definition

              A reference to an application-usable description of the identity that is represented by the signature.

              ShortThe party represented
              Comments

              The party that can't sign. For example a child.

              Control0..1
              TypeReference(Practitioner, PractitionerRole, RelatedPerson, Patient, Device, Organization)
              Is Modifierfalse
              Summarytrue
              Requirements

              used when the signature is on behalf of a non-signer.

              Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
              44. Signature.targetFormat
              Definition

              A mime type that indicates the technical format of the target resources signed by the signature.

              ShortThe technical format of the signed resources
              Comments

              "xml", "json" and "ttl" are allowed, which describe the simple encodings described in the specification (and imply appropriate bundle support). Otherwise, mime types are legal here.

              Control0..1
              BindingThe codes SHALL be taken from Mime Types
              (required to http://hl7.org/fhir/ValueSet/mimetypes|4.0.1)

              The mime type of an attachment. Any valid mime type is allowed.

              Typecode
              Is Modifierfalse
              Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
              Summaryfalse
              Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
              46. Signature.sigFormat
              Definition

              A mime type that indicates the technical format of the signature. Important mime types are application/signature+xml for X ML DigSig, application/jose for JWS, and image/* for a graphical image of a signature, etc.

              ShortThe technical format of the signature
              Control0..1
              BindingThe codes SHALL be taken from Mime Types
              (required to http://hl7.org/fhir/ValueSet/mimetypes|4.0.1)

              The mime type of an attachment. Any valid mime type is allowed.

              Typecode
              Is Modifierfalse
              Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
              Summaryfalse
              Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
              48. Signature.data
              Definition

              The base64 encoding of the Signature content. When signature is not recorded electronically this element would be empty.

              Shortbase64 encoded JWS-Signature
              Comments

              Where the signature type is an XML DigSig, the signed content is a FHIR Resource(s), the signature is of the XML form of the Resource(s) using XML-Signature (XMLDIG) "Detached Signature" form.

              Control1..1
              Typebase64Binary
              Is Modifierfalse
              Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
              Must Supporttrue
              Summaryfalse
              Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))