Netherlands - Generic Functions for data exchange Implementation Guide
0.2.0-ballot - ci-build

Netherlands - Generic Functions for data exchange Implementation Guide, published by Ministerie van Volksgezondheid, Welzijn en Sport. This guide is not an authorized publication; it is the continuous build for version 0.2.0-ballot built by the FHIR (HL7® FHIR® Standard) CI Build. This version is based on the current content of https://github.com/minvws/generiekefuncties-docs/ and changes regularly. See the Directory of published versions

## Resource Profile: NlGfOrganizationAffiliation - Detailed Descriptions

Draft as of 2026-03-24

Definitions for the nl-gf-organizationaffiliation resource profile.

- Key Elements Table
- Differential Elements Table
- Snapshot Elements Table

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

0. OrganizationAffiliation
Definition | Defines an affiliation/assotiation/relationship between 2 distinct oganizations, that is not a part-of relationship/sub-division relationship.
Short | Defines an affiliation/assotiation/relationship between 2 distinct oganizations, that is not a part-of relationship/sub-division relationship
Control | 0..*
Is Modifier | false
Complies with Profile | This profile complies with the profile mCSD Organization Affiliation
Summary | false
Invariants | dom-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. OrganizationAffiliation.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.
Short | A 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.
Control | 0..01
Type | uri
Is Modifier | true 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 Value | This primitive element may be present, or absent, or replaced by an extension
Summary | true
Invariants | ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
4. OrganizationAffiliation.extension
Definition | An Extension May be used to represent additional information that is not part of the basic definition of the resource. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.
Short | ExtensionAdditional 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.
Control | 0..*
Type | Extension
Is Modifier | false
Summary | false
Alternate Names | extensions, user content
Invariants | 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())
Slicing | This element introduces a set of slices on `OrganizationAffiliation.extension`. The slices areUnordered and Open, and can be differentiated using the following discriminators: value @ url
6. OrganizationAffiliation.extension:device
Slice Name | device
Definition | An identifier for a device, such as a software application.
Short | NL Generic Functions Device Identifier
Comments | An identifier for a device, such as a software application, that is used in the context of an affiliation between two organizations.
Control | 0..* This element is affected by the following invariants: ele-1
Type | Extension(NL Generic Functions Device Identifier) (Extension Type: Reference(NL Generic Functions Device Profile))
Is Modifier | false
Summary | false
Invariants | 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()`) ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
8. OrganizationAffiliation.modifierExtension
Definition | An Extension 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).
Short | ExtensionExtensions 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.
Control | 0..0*
Type | Extension
Is Modifier | true because Modifier extensions are expected to modify the meaning or interpretation of the resource that contains them
Summary | false
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 Names | extensions, user content
Invariants | 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())
10. OrganizationAffiliation.identifier
Definition | Business identifiers that are specific to this role.
Short | Business identifiers that are specific to this role
Note | This is a business identifier, not a resource identifier (see discussion)
Control | 10..*
Type | Identifier
Is Modifier | false
Summary | true
Requirements | Often, specific identities are assigned for the agent.
Invariants | ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
Slicing | This element introduces a set of slices on `OrganizationAffiliation.identifier`. The slices areUnordered and Open, and can be differentiated using the following discriminators: profile @ $this
12. OrganizationAffiliation.identifier:AssignedId
Slice Name | AssignedId
Definition | Business identifiers that are specific to this role.
Short | Business identifiers that are specific to this role
Note | This is a business identifier, not a resource identifier (see discussion)
Control | 10..1*
Type | Identifier(Custodian Assigned Identifier)
Is Modifier | false
Summary | true
Requirements | Often, specific identities are assigned for the agent.
Invariants | ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
14. OrganizationAffiliation.active
Definition | Whether this organization affiliation record is in active use.
Short | Whether this organization affiliation record is in active use
Comments | If this value is false, you may refer to the period to see when the role was in active use. If there is no period specified, no inference can be made about when it was active.
Control | 10..1
Type | boolean
Is Modifier | false
Primitive Value | This primitive element may be present, or absent, or replaced by an extension
Summary | true
Requirements | Need to be able to mark an organization affiliation record as not to be used because it was created in error, or otherwise no longer in active use.
Meaning if Missing | This resource is generally assumed to be active if no value is provided for the active element
Invariants | ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
16. OrganizationAffiliation.organization
Definition | Organization where the role is available (primary organization/has members).
Short | Organization where the role is available
Control | 10..1
Type | Reference(Organization)
Is Modifier | false
Summary | true
Invariants | ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
18. OrganizationAffiliation.participatingOrganization
Definition | The Participating Organization provides/performs the role(s) defined by the code to the Primary Organization (e.g. providing services or is a member of).
Short | Organization that provides/performs the role (e.g. providing services or is a member of)
Control | 10..1
Type | Reference(Organization)
Is Modifier | false
Summary | true
Invariants | ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
20. OrganizationAffiliation.network
Definition | Health insurance provider network in which the participatingOrganization provides the role's services (if defined) at the indicated locations (if defined).
Short | Health insurance provider network in which the participatingOrganization provides the role's services (if defined) at the indicated locations (if defined)
Control | 0..0*
Type | Reference(Organization)
Is Modifier | false
Summary | true
Invariants | ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
22. OrganizationAffiliation.code
Definition | Definition of the role the participatingOrganization plays in the association.
Short | Definition of the role the participatingOrganization plays
Control | 10..*
Binding | The codes SHALL be taken from For example codes, see NL GF Authorization Type ValueSet http://hl7.org/fhir/ValueSet/organization-role|4.0.1 (required to `http://minvws.github.io/generiekefuncties-docs/ValueSet/nl-gf-authorization-type-vs` )
Type | CodeableConcept
Is Modifier | false
Summary | true
Invariants | ele-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 foundhere

0. OrganizationAffiliation
Complies with Profile | This profile complies with the profile mCSD Organization Affiliation
2. OrganizationAffiliation.implicitRules
Control | 0..0
4. OrganizationAffiliation.extension
Slicing | This element introduces a set of slices on `OrganizationAffiliation.extension`. The slices areUnordered and Open, and can be differentiated using the following discriminators: value @ url
6. OrganizationAffiliation.extension:device
Slice Name | device
Comments | An identifier for a device, such as a software application, that is used in the context of an affiliation between two organizations.
Control | 0..*
Type | Extension(NL Generic Functions Device Identifier) (Extension Type: Reference(NL Generic Functions Device Profile))
8. OrganizationAffiliation.modifierExtension
Control | 0..0
10. OrganizationAffiliation.identifier
Note | This is a business identifier, not a resource identifier (see discussion)
Control | 1..?
Slicing | This element introduces a set of slices on `OrganizationAffiliation.identifier`. The slices areUnordered and Open, and can be differentiated using the following discriminators: profile @ $this
12. OrganizationAffiliation.identifier:AssignedId
Slice Name | AssignedId
Note | This is a business identifier, not a resource identifier (see discussion)
Control | 1..1
Type | Identifier(Custodian Assigned Identifier)
14. OrganizationAffiliation.active
Control | 1..?
16. OrganizationAffiliation.organization
Control | 1..?
18. OrganizationAffiliation.participatingOrganization
Control | 1..?
20. OrganizationAffiliation.network
Control | 0..0
22. OrganizationAffiliation.code
Control | 1..?
Binding | The codes SHALL be taken from NL GF Authorization Type ValueSet (required to `http://minvws.github.io/generiekefuncties-docs/ValueSet/nl-gf-authorization-type-vs` )

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

0. OrganizationAffiliation
Definition | Defines an affiliation/assotiation/relationship between 2 distinct oganizations, that is not a part-of relationship/sub-division relationship.
Short | Defines an affiliation/assotiation/relationship between 2 distinct oganizations, that is not a part-of relationship/sub-division relationship
Control | 0..*
Is Modifier | false
Complies with Profile | This profile complies with the profile mCSD Organization Affiliation
Summary | false
Invariants | dom-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. OrganizationAffiliation.id
Definition | The logical id of the resource, as used in the URL for the resource. Once assigned, this value never changes.
Short | Logical id of this artifact
Comments | The only time that a resource does not have an id is when it is being submitted to the server using a create operation.
Control | 0..1
Type | id
Is Modifier | false
Summary | true
4. OrganizationAffiliation.meta
Definition | 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.
Short | Metadata about the resource
Control | 0..1
Type | Meta
Is Modifier | false
Summary | true
Invariants | ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
6. OrganizationAffiliation.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.
Short | A 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.
Control | 0..0
Type | uri
Is Modifier | true 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 Value | This primitive element may be present, or absent, or replaced by an extension
Summary | true
Invariants | ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
8. OrganizationAffiliation.language
Definition | The base language in which the resource is written.
Short | Language of the resource content
Comments | 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).
Control | 0..1
Binding | The codes SHOULD be taken from CommonLanguages (preferred to `http://hl7.org/fhir/ValueSet/languages|4.0.1` ) A human language.
Additional Bindings | Purpose
AllLanguages | Max Binding
Type | code
Is Modifier | false
Primitive Value | This primitive element may be present, or absent, or replaced by an extension
Summary | false
Invariants | ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
10. OrganizationAffiliation.text
Definition | 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 "clinically safe" for a human to just read the narrative. Resource definitions may define what content should be represented in the narrative to ensure clinical safety.
Short | Text summary of the resource, for human interpretation
Comments | Contained resources do not have narrative. Resources that are not contained SHOULD have a narrative. In some cases, a resource may only have text with little or no additional discrete data (as long as all minOccurs=1 elements are satisfied). This may be necessary for data from legacy systems where information is captured as a "text blob" or where text is additionally entered raw or narrated and encoded information is added later.
Control | 0..1
Type | Narrative
Is Modifier | false
Summary | false
Alternate Names | narrative, html, xhtml, display
Invariants | ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
12. OrganizationAffiliation.contained
Definition | These resources do not have an independent existence apart from the resource that contains them - they cannot be identified independently, and nor can they have their own independent transaction scope.
Short | Contained, inline Resources
Comments | 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.
Control | 0..*
Type | Resource
Is Modifier | false
Summary | false
Alternate Names | inline resources, anonymous resources, contained resources
14. OrganizationAffiliation.extension
Definition | An Extension
Short | Extension
Control | 0..*
Type | Extension
Is Modifier | false
Summary | false
Invariants | 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()`)
Slicing | This element introduces a set of slices on `OrganizationAffiliation.extension`. The slices areUnordered and Open, and can be differentiated using the following discriminators: value @ url
16. OrganizationAffiliation.extension:device
Slice Name | device
Definition | An identifier for a device, such as a software application.
Short | NL Generic Functions Device Identifier
Comments | An identifier for a device, such as a software application, that is used in the context of an affiliation between two organizations.
Control | 0..* This element is affected by the following invariants: ele-1
Type | Extension(NL Generic Functions Device Identifier) (Extension Type: Reference(NL Generic Functions Device Profile))
Is Modifier | false
Summary | false
Invariants | 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()`)
18. OrganizationAffiliation.modifierExtension
Definition | An Extension
Short | Extension
Control | 0..0
Type | Extension
Is Modifier | true because Modifier extensions are expected to modify the meaning or interpretation of the resource that contains them
Summary | false
Invariants | 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()`)
20. OrganizationAffiliation.identifier
Definition | Business identifiers that are specific to this role.
Short | Business identifiers that are specific to this role
Note | This is a business identifier, not a resource identifier (see discussion)
Control | 1..*
Type | Identifier
Is Modifier | false
Summary | true
Requirements | Often, specific identities are assigned for the agent.
Invariants | ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
Slicing | This element introduces a set of slices on `OrganizationAffiliation.identifier`. The slices areUnordered and Open, and can be differentiated using the following discriminators: profile @ $this
22. OrganizationAffiliation.identifier:AssignedId
Slice Name | AssignedId
Definition | Business identifiers that are specific to this role.
Short | Business identifiers that are specific to this role
Note | This is a business identifier, not a resource identifier (see discussion)
Control | 1..1
Type | Identifier(Custodian Assigned Identifier)
Is Modifier | false
Summary | true
Requirements | Often, specific identities are assigned for the agent.
Invariants | ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
24. OrganizationAffiliation.active
Definition | Whether this organization affiliation record is in active use.
Short | Whether this organization affiliation record is in active use
Comments | If this value is false, you may refer to the period to see when the role was in active use. If there is no period specified, no inference can be made about when it was active.
Control | 1..1
Type | boolean
Is Modifier | false
Primitive Value | This primitive element may be present, or absent, or replaced by an extension
Summary | true
Requirements | Need to be able to mark an organization affiliation record as not to be used because it was created in error, or otherwise no longer in active use.
Meaning if Missing | This resource is generally assumed to be active if no value is provided for the active element
Invariants | ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
26. OrganizationAffiliation.period
Definition | The period during which the participatingOrganization is affiliated with the primary organization.
Short | The period during which the participatingOrganization is affiliated with the primary organization
Control | 0..1
Type | Period
Is Modifier | false
Summary | true
Requirements | An affiliation may be created ahead of time and only be active for a defined period of time. Once the affiliation is complete, the fact that it existed may still be required.
Invariants | ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
28. OrganizationAffiliation.organization
Definition | Organization where the role is available (primary organization/has members).
Short | Organization where the role is available
Control | 1..1
Type | Reference(Organization)
Is Modifier | false
Summary | true
Invariants | ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
30. OrganizationAffiliation.participatingOrganization
Definition | The Participating Organization provides/performs the role(s) defined by the code to the Primary Organization (e.g. providing services or is a member of).
Short | Organization that provides/performs the role (e.g. providing services or is a member of)
Control | 1..1
Type | Reference(Organization)
Is Modifier | false
Summary | true
Invariants | ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
32. OrganizationAffiliation.network
Definition | Health insurance provider network in which the participatingOrganization provides the role's services (if defined) at the indicated locations (if defined).
Short | Health insurance provider network in which the participatingOrganization provides the role's services (if defined) at the indicated locations (if defined)
Control | 0..0
Type | Reference(Organization)
Is Modifier | false
Summary | true
Invariants | ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
34. OrganizationAffiliation.code
Definition | Definition of the role the participatingOrganization plays in the association.
Short | Definition of the role the participatingOrganization plays
Control | 1..*
Binding | The codes SHALL be taken from NL GF Authorization Type ValueSet (required to `http://minvws.github.io/generiekefuncties-docs/ValueSet/nl-gf-authorization-type-vs` )
Type | CodeableConcept
Is Modifier | false
Summary | true
Invariants | ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
36. OrganizationAffiliation.specialty
Definition | Specific specialty of the participatingOrganization in the context of the role.
Short | Specific specialty of the participatingOrganization in the context of the role
Control | 0..*
Binding | The codes SHOULD be taken from PracticeSettingCodeValueSet (preferred to `http://hl7.org/fhir/ValueSet/c80-practice-codes|4.0.1` ) Specific specialty associated with the participating organization.
Type | CodeableConcept
Is Modifier | false
Summary | true
Invariants | ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
38. OrganizationAffiliation.location
Definition | The location(s) at which the role occurs.
Short | The location(s) at which the role occurs
Control | 0..*
Type | Reference(Location)
Is Modifier | false
Summary | true
Invariants | ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
40. OrganizationAffiliation.healthcareService
Definition | Healthcare services provided through the role.
Short | Healthcare services provided through the role
Control | 0..*
Type | Reference(HealthcareService)
Is Modifier | false
Summary | false
Invariants | ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
42. OrganizationAffiliation.telecom
Definition | Contact details at the participatingOrganization relevant to this Affiliation.
Short | Contact details at the participatingOrganization relevant to this Affiliation
Control | 0..*
Type | ContactPoint
Is Modifier | false
Summary | true
Requirements | Sometimes a participating organization provides dedicated contacts to handle enquiries specifically for the role provided to the affiliated organization.
Invariants | ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
44. OrganizationAffiliation.endpoint
Definition | Technical endpoints providing access to services operated for this role.
Short | Technical endpoints providing access to services operated for this role
Control | 0..*
Type | Reference(Endpoint)
Is Modifier | false
Summary | false
Invariants | ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)