# NDH Extensions - National Directory of Healthcare Providers & Services (NDH) Implementation Guide v2.0.0-current

## NDH Extensions

To address the particular use case requirements of the NDH, a set of extensions are defined:

[NDH Accessibility](StructureDefinition-base-ext-accessibility.md)

This extension enables NDH to communicate accessibility accommodations for practitioners and locations in a consistent, computable form, using a coded value with extensible binding to AccessibilityVS for interoperable discovery and filtering; it is used in Location and Practitioner.

[NDH Aligned with CMS Data Network](StructureDefinition-base-ext-aligned-with-cms-data-network.md)

This extension enables NDH to assert alignment with the CMS data network using a required boolean indicator for straightforward policy and participation checks; it is used in Practitioner and Organization.

[NDH Associated Servers](StructureDefinition-base-ext-associatedServers.md)

This extension enables NDH to represent endpoint-to-server associations so implementers can publish alternate or companion server routes for operational flexibility, with structured sub-extensions for server type and server URL and an extensible binding to NdhAssociatedServersTypeVS for consistent classification; it is used in Endpoint.

[NDH CMS Enrollment In Good Standing](StructureDefinition-base-ext-cms-enrollment-in-good-standing.md)

This extension enables NDH to assert whether an artifact is enrolled with CMS and currently in good standing, using a required boolean for unambiguous compliance signaling; it is used in Practitioner, Organization, and VerificationResult.

[NDH CMS IAL2 Verified](StructureDefinition-base-ext-cms-ial2-verified.md)

This extension enables NDH to assert CMS IAL2 identity assurance verification status for an artifact using a required boolean indicator; it is used in Practitioner, Organization, and VerificationResult.

[NDH Communication Proficiency](StructureDefinition-base-ext-communication-proficiency.md)

This extension enables NDH to encode a practitioner's language proficiency level for a declared communication language, using a CodeableConcept bound extensibly to ILRReadingScaleVS to support consistent language-access matching; it is used in Practitioner.communication.

[NDH Delivery Method](StructureDefinition-base-ext-delivery-method.md)

This extension enables NDH to declare how a service is delivered and, when virtual, which modalities are supported, using structured sub-extensions and ValueSet bindings to DeliveryMethodVS and VirtualModalitiesVS for predictable service-access routing; it is used in HealthcareService.

[NDH Dynamic Registration](StructureDefinition-base-ext-dynamicRegistration.md)

This extension enables NDH to convey dynamic client-registration capabilities for trust-framework participation, using sub-extensions for trust profile and version and an extensible binding to TrustProfileVS to standardize runtime registration signaling; it is used in Endpoint.

[NDH Endpoint EnvironmentType](StructureDefinition-base-ext-endpoint-environment-type.md)

This extension enables NDH to classify endpoint environment context, using a CodeableConcept with extensible binding to NdhEndpointEnvironmentVS so consumers can distinguish operational deployment targets consistently; it is used in Endpoint.

[NDH Endpoint IHE Specific Connection Type](StructureDefinition-base-ext-endpoint-ihe-specific-connection-type.md)

This extension enables NDH to represent IHE-specific endpoint connection semantics when base connectionType coding is insufficiently granular, using a preferred binding to EndpointIheSpecificConnectionTypeVS for more precise interoperability declarations; it is used in Endpoint.

[NDH Endpoint Rank](StructureDefinition-base-ext-endpoint-rank.md)

This extension enables NDH to express preferred ordering among functionally equivalent endpoints, using a required positive integer so clients can deterministically select connection priority; it is used in Endpoint.

[NDH Endpoint Reference](StructureDefinition-base-ext-endpoint-reference.md)

This extension enables NDH to attach a direct reference to an NDH Endpoint resource so technical exchange capabilities can be resolved from practitioner-facing directory data; it is used in Practitioner.

[NDH Endpoint Testing Certification](StructureDefinition-base-ext-endpoint-testing-certification.md)

This extension enables NDH to document endpoint testing and certification evidence, including tester, method, certificate artifact, and relevant timestamps, using structured sub-extensions and an extensible binding to EndpointTestingMethodVS for harmonized test-method representation; it is used in Endpoint.

[NDH Endpoint Access Control Mechanism](StructureDefinition-base-ext-endpointAccessControlMechanism.md)

This extension enables NDH to declare endpoint access-control approach for secure and scalable exchange, using an extensible binding to EndpointAccessControlMechanismVS so clients can align connection behavior with expected authorization patterns; it is used in Endpoint.

[NDH Funding Source](StructureDefinition-base-ext-fundingSource.md)

This extension enables NDH to identify funding provenance for services and organizations, using structured sub-extensions for funding identifiers, funding organizations, and source text to support financial-context transparency in directory records; it is used in HealthcareService and Organization.

[NDH Identifier Status](StructureDefinition-base-ext-identifier-status.md)

This extension enables NDH to assert lifecycle status for identifiers in a normalized way, using required code binding to IdentifierStatusVS so consumers can consistently interpret identifier validity and operational state; it is used in Identifier.

[NDH Implementation Guide Supported](StructureDefinition-base-ext-implementation-guide.md)

This extension enables NDH to declare implementation-guide compatibility for endpoints when standard connection-type coding does not fully describe behavior, using structured sub-extensions for IG URI, name, use case, version, actor, and options with extensible use-case binding to NdhImplementationGuideVS; it is used in Endpoint.

[NDH InsurancePlan Reference](StructureDefinition-base-ext-insuranceplan-reference.md)

This extension enables NDH to link organizations to accepted NDH InsurancePlan resources, providing explicit plan participation references for accurate plan-organization discovery; it is used in Organization.

[NDH Language Speak](StructureDefinition-base-ext-language-speak.md)

This extension enables NDH to represent spoken language capability at telecom contact points, using extensible binding to LanguagesVS to improve language-concordant access and communication routing; it is used in HealthcareService.telecom, Location.telecom, and Organization.telecom.

[NDH Location Reference](StructureDefinition-base-ext-location-reference.md)

This extension enables NDH to declare NDH Location-based coverage areas, supporting clear network and organizational service-geography linkage for downstream eligibility and routing decisions; it is used in Organization.

[NDH Logo](StructureDefinition-base-ext-logo.md)

This extension enables NDH to attach a canonical visual identity artifact for services and organizations using an Attachment value, supporting recognizable presentation across directory consumers; it is used in HealthcareService, Organization, and OrganizationAffiliation.

[NDH Age Group](StructureDefinition-base-ext-ndh-age-group.md)

This extension enables NDH to represent age-based eligibility categories as coded concepts with extensible binding to AgeGroupVS for consistent age-group filtering; it is used as a nested extension within base-ext-service-or-program-requirement.

[NDH Age Range](StructureDefinition-base-ext-ndh-age-range.md)

This extension enables NDH to represent age-based eligibility as a structured Range value for service and program requirement evaluation; it is used as a nested extension within base-ext-service-or-program-requirement.

[NDH Network Reference](StructureDefinition-base-ext-network-reference.md)

This extension enables NDH to explicitly link practitioner roles and services to participating NDH Network resources, improving network participation discovery and filtering; it is used in PractitionerRole and HealthcareService.

[NDH New Patients Characteristics](StructureDefinition-base-ext-newpatients-characteristics.md)

This extension enables NDH to capture additional qualifiers about accepted new-patient populations as textual characteristics, complementing structured acceptance indicators in NewPatients workflows; it is used as a nested extension within base-ext-newpatients.

[NDH New Patients](StructureDefinition-base-ext-newpatients.md)

This extension enables NDH to represent new-patient acceptance policy with optional network specificity and contextual characteristics, using structured sub-extensions and required binding to AcceptingPatientsVS so access status can be compared consistently across roles, services, and locations; it is used in HealthcareService, Location, and PractitionerRole.

[NDH Organization Alias Period](StructureDefinition-base-ext-org-alias-period.md)

This extension enables NDH to time-bound organization alias validity with a Period value so consumers can distinguish current from historical alternate names; it is used in Organization.alias.

[NDH Organization Alias Type](StructureDefinition-base-ext-org-alias-type.md)

This extension enables NDH to classify organization aliases by usage type, using a CodeableConcept bound by example to OrgAliasTypeVS to support clearer interpretation of alternate naming; it is used in Organization.alias.

[NDH Org Description](StructureDefinition-base-ext-org-description.md)

This extension enables NDH to provide a concise human-readable narrative describing an organization's purpose or scope, improving directory comprehension beyond coded attributes; it is used in Organization.

[NDH Payment Accepted](StructureDefinition-base-ext-paymentAccepted.md)

This extension enables NDH to state accepted payment methods for services or organizations, using required binding to paymentTypeVS for interoperable financial-access signaling; it is used in HealthcareService and Organization.

[NDH Practitioner Qualification Scope where valid and status](StructureDefinition-base-ext-practitioner-qualification-scope.md)

This extension enables NDH to qualify practitioner credentials with explicit status and jurisdictional validity, using structured sub-extensions with required bindings to QualificationStatusVS and US-core state semantics for computable credential governance; it is used in Practitioner.qualification.

[NDH Rating Details](StructureDefinition-base-ext-rating-details.md)

This extension enables NDH to carry supplemental rating metadata, including rating system, rating type, and rating value, so implementer-defined scoring models can be represented with clearer provenance and meaning; it is used as a nested extension within base-ext-rating.

[NDH Rating](StructureDefinition-base-ext-rating.md)

This extension enables NDH to represent ratings for services, organizations, practitioners, and roles, with structured support for rating type, quantitative or textual values, and optional nested RatingDetails for richer comparative quality signals; it is used in HealthcareService, Organization, Practitioner, and PractitionerRole.

[NDH Required Document](StructureDefinition-base-ext-requiredDocument.md)

This extension enables NDH to enumerate documents required to access or use a service, using structured identifier and document sub-extensions to support intake readiness and pre-visit transparency; it is used in HealthcareService.

[NDH Secure Exchange Artifacts](StructureDefinition-base-ext-secureExchangeArtifacts.md)

This extension enables NDH to publish key secure-exchange artifacts needed for trust establishment, including artifact type, certificate payload, and expiration, with extensible binding to NdhSecureExchangeArtifactsVS for interoperable certificate-discovery workflows; it is used in Endpoint.

[NDH Security Details](StructureDefinition-base-ext-security-details.md)

This extension enables NDH to communicate endpoint trust-framework security context, including framework type, qualifiers, signed artifacts, and public certificates, with extensible TrustFrameworkTypeVS binding to support consistent policy interpretation across trust communities; it is used in Endpoint.

[Service Offered for a Group](StructureDefinition-base-ext-service-offered.md)

This extension represents a service offered by a group, which can be used to describe the types of services provided by a multidisciplinary provider group in the context of coordinated care delivery. It allows for the inclusion of multiple services, each represented as a CodeableConcept, to capture the range of services that a group may offer to patients or clients.

[NDH HealthcareService or Program Requirement](StructureDefinition-base-ext-service-or-program-requirement.md)

This extension enables NDH to encode participation criteria for services and programs using structured demographic and coverage-related sub-extensions, including age range/group, birth sex, employment, insurance, veteran status, and preferred language, with ValueSet bindings that support consistent eligibility interpretation; it is used in HealthcareService.

[NDH Verification Status](StructureDefinition-base-ext-verification-status.md)

This extension enables NDH to communicate verification standing for directory resources in a consistent coded format, using an extensible binding to NdhVerificationStatusVS for trust-state interoperability; it is used in Endpoint, HealthcareService, InsurancePlan, Location, Organization, OrganizationAffiliation, Practitioner, PractitionerRole, and Group.