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: DDCCQuestionnaireResponse - Detailed Descriptions

Draft as of 2025-03-10

Definitions for the DDCCQuestionnaireResponse resource profile.

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

0. QuestionnaireResponse
Definition

Sets expectations for supported capabilities for questionnaire responses for SDC-conformant systems.


A structured set of questions and their answers. The questions are ordered and grouped into coherent subsets, corresponding to the structure of the grouping of the questionnaire being responded to.

ShortSDC Questionnaire ResponseA structured set of questions and their answers
Comments

The QuestionnaireResponse contains enough information about the questions asked and their organization that it can be interpreted somewhat independently from the Questionnaire it is based on. I.e. You don't need access to the Questionnaire in order to extract basic information from a QuestionnaireResponse.

Control0..*
Is Modifierfalse
Must Supportfalse
Summaryfalse
Alternate NamesForm, QuestionnaireAnswers, Form Data
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())
sdcqr-1: Subject SHOULD be present (searching is difficult without subject). Almost all QuestionnaireResponses should be with respect to some sort of subject. (subject.exists())
sdcqr-2: When repeats=true for a group, it'll be represented with multiple items with the same linkId in the QuestionnaireResponse. For a question, it'll be represented by a single item with that linkId with multiple answers. ((QuestionnaireResponse|repeat(answer|item)).select(item.where(answer.value.exists()).linkId.isDistinct()).allTrue())
2. QuestionnaireResponse.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. QuestionnaireResponse.extension:signature
Slice Namesignature
Definition

Represents a wet or electronic signature for either the form overall or for the question or item it's associated with.

ShortA signature attesting to the content
Control0..*
TypeExtension(QuestionnaireResponse Signature) (Extension Type: Signature)
Is Modifierfalse
Must Supportfalse
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())
ele-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. QuestionnaireResponse.extension:completionMode
Slice NamecompletionMode
Definition

Indicates how the individual completing the QuestionnaireResponse provided their responses.

ShortE.g. Verbal, written, electronic
Control0..1
TypeExtension(QuestionnaireResponse Completion Mode) (Extension Type: CodeableConcept)
Is Modifierfalse
Must Supportfalse
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())
ele-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())
8. QuestionnaireResponse.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())
10. QuestionnaireResponse.identifier
Definition

A business identifier assigned to a particular completed (or partially completed) questionnaire.

ShortUnique id for this set of answers
NoteThis is a business identifier, not a resource identifier (see discussion)
Control0..1
TypeIdentifier
Is Modifierfalse
Must Supporttrue
Summarytrue
Requirements

Used for tracking, registration and other business purposes.

Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
12. QuestionnaireResponse.questionnaire
Definition

The Questionnaire that defines and organizes the questions for which answers are being provided.

ShortForm being answered
Comments

For SDC, this SHALL be the version-specific URL of the form as hosted on the Form Manager.


If a QuestionnaireResponse references a Questionnaire, then the QuestionnaireResponse structure must be consistent with the Questionnaire (i.e. questions must be organized into the same groups, nested questions must still be nested, etc.).

Control10..1
Typecanonical(SDCBaseQuestionnaire, Questionnaire)
Is Modifierfalse
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Must Supporttrue
Summarytrue
Requirements

Needed to allow editing of the questionnaire response in a manner that enforces the constraints of the original form.

Alternate NamesForm
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
14. QuestionnaireResponse.questionnaire.extension:questionnaireDisplay
Slice NamequestionnaireDisplay
Definition

The title or other name to display when referencing a resource by canonical URL.

ShortDisplay name for canonical reference
Comments

This SHALL be the title of the Questionnaire at the time the QuestionnaireResponse was originally authored.

Control0..1
TypeExtension(Display Name) (Extension Type: string)
Is Modifierfalse
Must Supporttrue
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())
ele-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())
16. QuestionnaireResponse.status
Definition

The position of the questionnaire response within its overall lifecycle.

Shortin-progress | completed | amended | entered-in-error | stopped
Comments

This element is labeled as a modifier because the status contains codes that mark the resource as not currently valid.

Control1..1
BindingThe codes SHALL be taken from QuestionnaireResponseStatushttp://hl7.org/fhir/ValueSet/questionnaire-answers-status|4.0.1
(required to http://hl7.org/fhir/ValueSet/questionnaire-answers-status|4.0.1)

Lifecycle status of the questionnaire response.

Typecode
Is Modifiertrue because This element is labelled as a modifier because it is a status element that contains status entered-in-error which means that the resource should not be treated as valid
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Must Supporttrue
Summarytrue
Requirements

The information on Questionnaire resources may possibly be gathered during multiple sessions and altered after considered being finished.

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

The subject of the questionnaire response. This could be a patient, organization, practitioner, device, etc. This is who/what the answers apply to, but is not necessarily the source of information.

ShortThe subject of the questions
Comments

If the Questionnaire declared a subjectType, the resource pointed to by this element must be an instance of one of the listed types. If subject is omitted - because the QuestionnaireResponse is not associated with a specific subject, ensure that QuestionnaireRsponse.identifier is present or the QuestionnaireResponse is referenced somewhere (e.g. Task.output, Composition.section.entry, etc.) to allow tracking and retrieval of the QuestionnaireResponse


If the Questionnaire declared a subjectType, the resource pointed to by this element must be an instance of one of the listed types.

Control0..1
TypeReference(Resource)
Is Modifierfalse
Must Supporttrue
Summarytrue
Requirements

Allows linking the answers to the individual the answers describe. May also affect access control.

Alternate NamesPatient, Focus
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
20. QuestionnaireResponse.authored
Definition

Identifies when this version of the answer set was created. Changes whenever the answers are updated.


The date and/or time that this set of answers were last changed.

ShortDate the answers were gathered
Comments

May be different from the lastUpdateTime of the resource itself, because that reflects when the data was known to the server, not when the data was captured.

This element is optional to allow for systems that might not know the value, however it SHOULD be populated if possible.

Control10..1
TypedateTime
Is Modifierfalse
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Must Supporttrue
Summarytrue
Requirements

Clinicians need to be able to check the date that the information in the questionnaire was collected, to derive the context of the answers.

Alternate NamesDate Created, Date published, Date Issued, Date updated
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
22. QuestionnaireResponse.author
Definition

Person who received the answers to the questions in the QuestionnaireResponse and recorded them in the system.

ShortPerson who received and recorded the answers
Comments

Mapping a subject's answers to multiple choice options and determining what to put in the textual answer is a matter of interpretation. Authoring by device would indicate that some portion of the questionnaire had been auto-populated.

Control0..1
TypeReference(Device, Practitioner, PractitionerRole, Patient, RelatedPerson, Organization)
Is Modifierfalse
Must Supporttrue
Must Support TypesNo must-support rules about the choice of types/profiles
Summarytrue
Requirements

Need to know who interpreted the subject's answers to the questions in the questionnaire, and selected the appropriate options for answers.

Alternate NamesLaboratory, Service, Practitioner, Department, Company, Performer
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
24. QuestionnaireResponse.item
Definition

A group or question item from the original questionnaire for which answers are provided.

ShortGroups and questions
Comments

Groups cannot have answers and therefore must nest directly within item. When dealing with questions, nesting must occur within each answer because some questions may have multiple answers (and the nesting occurs for each answer).

Control0..*
TypeBackboneElement
Is Modifierfalse
Must Supporttrue
Summaryfalse
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
qrs-1: Nested item can't be beneath both item and answer ((answer.exists() and item.exists()).not())
qrs-1: Nested item can't be beneath both item and answer ((answer.exists() and item.exists()).not())
26. QuestionnaireResponse.item.extension:itemMedia
Slice NameitemMedia
Definition

Media to render/make available as an accompaniment to the question being asked

ShortMedia to display
Control0..1
This element is affected by the following invariants: ele-1
TypeExtension(Item Media) (Extension Type: Attachment)
Is Modifierfalse
Must Supportfalse
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())
ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
28. QuestionnaireResponse.item.extension:ItemSignature
Slice NameItemSignature
Definition

Represents a wet or electronic signature for either the form overall or for the question or item it's associated with.

ShortA signature attesting to the content
Control0..*
TypeExtension(QuestionnaireResponse Signature) (Extension Type: Signature)
Is Modifierfalse
Must Supportfalse
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())
ele-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())
30. QuestionnaireResponse.item.modifierExtension
Definition

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

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

ShortExtensions that cannot be ignored even if unrecognized
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 element that contains them
Summarytrue
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, modifiers
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())
32. QuestionnaireResponse.item.linkId
Definition

The item from the Questionnaire that corresponds to this item in the QuestionnaireResponse resource.

ShortPointer to specific item from Questionnaire
Control1..1
Typestring
Is Modifierfalse
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Must Supporttrue
Summaryfalse
Requirements

Items can repeat in the answers, so a direct 1..1 correspondence by position might not exist - requiring correspondence by identifier.

Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
34. QuestionnaireResponse.item.text
Definition

Text that is displayed above the contents of the group or as the text of the question being answered.

ShortName for group or question text
Control0..1
Typestring
Is Modifierfalse
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Must Supporttrue
Summaryfalse
Requirements

Allows the questionnaire response to be read without access to the questionnaire.

Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
36. QuestionnaireResponse.item.answer
Definition

The respondent's answer(s) to the question.

ShortThe response(s) to the question
Comments

The value is nested because we cannot have a repeating structure that has variable type.

Control0..*
TypeBackboneElement
Is Modifierfalse
Must Supporttrue
Summaryfalse
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
38. QuestionnaireResponse.item.answer.extension:itemAnswerMedia
Slice NameitemAnswerMedia
Definition

Media to render/make available as an accompaniment to a specific answer option

ShortAnswer Media to display
Control0..1
This element is affected by the following invariants: ele-1
TypeExtension(Item Answer Media) (Extension Type: Attachment)
Is Modifierfalse
Must Supportfalse
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())
ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
40. QuestionnaireResponse.item.answer.extension:ordinalValue
Slice NameordinalValue
Definition

A numeric value that allows the comparison (less than, greater than) or other numerical manipulation of a concept (e.g. Adding up components of a score). Scores are usually a whole number, but occasionally decimals are encountered in scores.

ShortAssigned Ordinal Value
Comments

Scores are commonly encountered in various clinical assessment scales. Assigning a value to a concept should generally be done in a formal code system that defines the value, or in an applicable value set for the concept, but some concepts do not have a formal definition (or are not even represented as a concept formally, especially in Questionnaires, so this extension is allowed to appear ouside those preferred contexts. Scores may even be assigned arbitrarily during use (hence, on Coding). The value may be constrained to an integer in some contexts of use. Todo: Scoring algorithms may also be defined directly, but how this is done is not yet defined.

Control0..1
TypeExtension(Ordinal Value) (Extension Type: decimal)
Is Modifierfalse
Must Supportfalse
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())
ele-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())
42. QuestionnaireResponse.item.answer.modifierExtension
Definition

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

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

ShortExtensions that cannot be ignored even if unrecognized
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 element that contains them
Summarytrue
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, modifiers
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())
44. QuestionnaireResponse.item.answer.value[x]
Definition

The answer (or one of the answers) provided by the respondent to the question.

ShortSingle-valued answer to the question
Comments

More complex structures (Attachment, Resource and Quantity) will typically be limited to electronic forms that can expose an appropriate user interface to capture the components and enforce the constraints of a complex data type. Additional complex types can be introduced through extensions. Must match the datatype specified by Questionnaire.item.type in the corresponding Questionnaire.

Control0..1
BindingFor example codes, see QuestionnaireAnswerCodeshttp://hl7.org/fhir/ValueSet/questionnaire-answers
(example to http://hl7.org/fhir/ValueSet/questionnaire-answers)

Code indicating the response provided for a question.

TypeChoice of: boolean, date, dateTime, time, decimal, integer, string, Coding, uri, Quantity, Attachment, Reference(Resource)
[x] NoteSeeChoice of Data Typesfor further information about how to use [x]
Is Modifierfalse
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Must Supporttrue
Must Support TypesNo must-support rules about the choice of types/profiles
Summaryfalse
Requirements

Ability to retain a single-valued answer to a question.

Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
46. QuestionnaireResponse.item.answer.item
Definition

Nested groups and/or questions found within this particular answer.

ShortNested groups and questions
Control0..*
TypeSeettp://hl7.org/fhir/StructureDefinition/QuestionnaireResponse#QuestionnaireResponse.item
Is Modifierfalse
Must Supporttrue
Summaryfalse
Requirements

It is useful to have "sub-questions", questions which normally appear when certain answers are given and which collect additional details.

Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
48. QuestionnaireResponse.item.item
Definition

Questions or sub-groups nested beneath a question or group.

ShortNested questionnaire response items
Control0..*
TypeSeettp://hl7.org/fhir/StructureDefinition/QuestionnaireResponse#QuestionnaireResponse.item
Is Modifierfalse
Must Supporttrue
Summaryfalse
Requirements

Reports can consist of complex nested groups.

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