WHO Digital Documentation of COVID-19 Certificates (DDCC)
1.0.0 - CI Build International flag

WHO Digital Documentation of COVID-19 Certificates (DDCC), published by WHO. This guide is not an authorized publication; it is the continuous build for version 1.0.0 built by the FHIR (HL7® FHIR® Standard) CI Build. This version is based on the current content of https://github.com/WorldHealthOrganization/ddcc/tree/main and changes regularly. See the Directory of published versions

Resource Profile: DDCCPractitioner - Detailed Descriptions

Draft as of 2025-03-10

Definitions for the DDCCPractitioner resource profile.

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

0. Practitioner
Definition

A person who is directly or indirectly involved in the provisioning of healthcare.

ShortA person with a formal responsibility in the provisioning of healthcare or related services
Control0..*
Is Modifierfalse
Summaryfalse
Invariantsdom-2: If the resource is contained in another resource, it SHALL NOT contain nested Resources (contained.contained.empty())
dom-3: 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 (contained.where((('#'+id in (%resource.descendants().reference | %resource.descendants().as(canonical) | %resource.descendants().as(uri) | %resource.descendants().as(url))) or descendants().where(reference = '#').exists() or descendants().where(as(canonical) = '#').exists() or descendants().where(as(canonical) = '#').exists()).not()).trace('unmatched', id).empty())
dom-4: If a resource is contained in another resource, it SHALL NOT have a meta.versionId or a meta.lastUpdated (contained.meta.versionId.empty() and contained.meta.lastUpdated.empty())
dom-5: If a resource is contained in another resource, it SHALL NOT have a security label (contained.meta.security.empty())
dom-6: A resource should have narrative for robust management (text.`div`.exists())
2. Practitioner.implicitRules
Definition

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.

ShortA set of rules under which this content was created
Comments

Asserting this rule set restricts the content to be only understood by a limited set of trading partners. This inherently limits the usefulness of the data in the long term. However, the existing health eco-system is highly fractured, and not yet ready to define, collect, and exchange data in a generally computable sense. Wherever possible, implementers and/or specification writers should avoid using this element. Often, when used, the URL is a reference to an implementation guide that defines these special rules as part of it's narrative along with other profiles, value sets, etc.

Control0..1
Typeuri
Is Modifiertrue because This element is labeled as a modifier because the implicit rules may provide additional knowledge about the resource that modifies it's meaning or interpretation
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()))
4. Practitioner.modifierExtension
Definition

May be used to represent additional information that is not part of the basic definition of the resource and that modifies the understanding of the element that contains it and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer is allowed to define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions.

Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself).

ShortExtensions that cannot be ignored
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 Modifiertrue because Modifier extensions are expected to modify the meaning or interpretation of the resource that contains them
Summaryfalse
Requirements

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.

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())
6. Practitioner.identifier
Definition

An identifier that applies to this person in this role.

ShortAn identifier for the person as this agent
NoteThis is a business identifier, not a resource identifier (see discussion)
Control10..*
TypeIdentifier
Is Modifierfalse
Must Supporttrue
Summarytrue
Requirements

Often, specific identities are assigned for the agent.

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 Practitioner.identifier. The slices areOrdered and Open, and can be differentiated using the following discriminators:
  • value @ use
  • profile @ assigner.resolve()
  • 8. Practitioner.identifier:ddccIdentifier
    Slice NameddccIdentifier
    Definition

    An identifier that applies to this person in this role.

    ShortAn identifier for the person as this agent
    NoteThis is a business identifier, not a resource identifier (see discussion)
    Control10..*
    TypeIdentifier
    Is Modifierfalse
    Summarytrue
    Requirements

    Often, specific identities are assigned for the agent.

    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    10. Practitioner.identifier:ddccIdentifier.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.

    Control10..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
    Must Supporttrue
    Summarytrue
    Requirements

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

    Pattern Valueofficial
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    12. Practitioner.identifier:ddccIdentifier.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.

    Control10..1
    Typeuri
    Is Modifierfalse
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Must Supporttrue
    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()))
    14. Practitioner.identifier:ddccIdentifier.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()))
    16. Practitioner.identifier:ddccIdentifier.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.

    Control10..1
    TypeReference(DDCC Organization, Organization)
    Is Modifierfalse
    Must Supporttrue
    Summarytrue
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))