{
  "resourceType": "StructureDefinition",
  "id": "Extension-England-TypedPeriod",
  "url": "https://fhir.nhs.uk/England/StructureDefinition/Extension-England-TypedPeriod",
  "version": "1.1.0",
  "name": "ExtensionEnglandTypedPeriod",
  "title": "Extension England Typed Period",
  "status": "active",
  "date": "2025-06-25",
  "publisher": "NHS England",
  "contact": [
    {
      "name": "NHS England",
      "telecom": [
        {
          "system": "email",
          "value": "interoperabilityteam@nhs.net",
          "use": "work",
          "rank": 1
        }
      ]
    }
  ],
  "description": "This supports the exchange of time periods. The extension time period is carried along with a code to identify whether the data is recorded for legal, operational, or system effective periods",
  "purpose": "This extension has been created from an ODS use-case in which there is a requirement to hold data for Legal and Operational dates, an additional code value of system-effective period, is now added to enable the use of this extension in RelatedPerson network use case.",
  "copyright": "Copyright © 2023+ NHS England Licensed under the Apache License, Version 2.0 (the \\\"License\\\"); you may not use this file except in compliance with the License. You may obtain a copy of the License at  http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an \\\"AS IS\\\" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. HL7® FHIR® standard Copyright © 2011+ HL7 The HL7® FHIR® standard is used under the FHIR license. You may obtain a copy of the FHIR license at  https://www.hl7.org/fhir/license.html.",
  "fhirVersion": "4.0.1",
  "mapping": [
    {
      "identity": "rim",
      "uri": "http://hl7.org/v3",
      "name": "RIM Mapping"
    }
  ],
  "kind": "complex-type",
  "abstract": false,
  "context": [
    {
      "type": "element",
      "expression": "Organization"
    },
    {
      "type": "element",
      "expression": "OrganizationAffiliation"
    },
    {
      "type": "extension",
      "expression": "https://fhir.nhs.uk/England/StructureDefinition/Extension-England-OrganisationRole"
    },
    {
      "type": "element",
      "expression": "RelatedPerson"
    }
  ],
  "type": "Extension",
  "baseDefinition": "http://hl7.org/fhir/StructureDefinition/Extension",
  "derivation": "constraint",
  "snapshot": {
    "element": [
      {
        "id": "Extension",
        "path": "Extension",
        "short": "This supports the recording of a period related to the specified date type.",
        "definition": "This supports the recording of a period related to the specified date type. The date/time period is carried along with a code to identify the type of period.",
        "min": 0,
        "max": "*",
        "base": {
          "path": "Extension",
          "min": 0,
          "max": "*"
        },
        "condition": [
          "ele-1"
        ],
        "constraint": [
          {
            "key": "ele-1",
            "severity": "error",
            "human": "All FHIR elements must have a @value or children",
            "expression": "hasValue() or (children().count() > id.count())",
            "xpath": "@value|f:*|h:div",
            "source": "http://hl7.org/fhir/StructureDefinition/Element"
          },
          {
            "key": "ext-1",
            "severity": "error",
            "human": "Must have either extensions or value[x], not both",
            "expression": "extension.exists() != value.exists()",
            "xpath": "exists(f:extension)!=exists(f:*[starts-with(local-name(.), 'value')])",
            "source": "http://hl7.org/fhir/StructureDefinition/Extension"
          }
        ],
        "mapping": [
          {
            "identity": "rim",
            "map": "n/a"
          },
          {
            "identity": "rim",
            "map": "N/A"
          }
        ]
      },
      {
        "id": "Extension.id",
        "path": "Extension.id",
        "representation": [
          "xmlAttr"
        ],
        "short": "Unique id for inter-element referencing",
        "definition": "Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.",
        "min": 0,
        "max": "1",
        "base": {
          "path": "Element.id",
          "min": 0,
          "max": "1"
        },
        "type": [
          {
            "extension": [
              {
                "url": "http://hl7.org/fhir/StructureDefinition/structuredefinition-fhir-type",
                "valueUrl": "string"
              }
            ],
            "code": "http://hl7.org/fhirpath/System.String"
          }
        ],
        "mapping": [
          {
            "identity": "rim",
            "map": "n/a"
          }
        ]
      },
      {
        "id": "Extension.extension",
        "path": "Extension.extension",
        "slicing": {
          "discriminator": [
            {
              "type": "value",
              "path": "url"
            }
          ],
          "description": "Extensions are always sliced by (at least) url",
          "rules": "open"
        },
        "short": "Additional content defined by implementations",
        "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.",
        "comment": "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.",
        "alias": [
          "extensions",
          "user content"
        ],
        "min": 2,
        "max": "*",
        "base": {
          "path": "Element.extension",
          "min": 0,
          "max": "*"
        },
        "type": [
          {
            "code": "Extension"
          }
        ],
        "condition": [
          "ele-1"
        ],
        "constraint": [
          {
            "key": "ele-1",
            "severity": "error",
            "human": "All FHIR elements must have a @value or children",
            "expression": "hasValue() or (children().count() > id.count())",
            "xpath": "@value|f:*|h:div",
            "source": "http://hl7.org/fhir/StructureDefinition/Element"
          },
          {
            "key": "ext-1",
            "severity": "error",
            "human": "Must have either extensions or value[x], not both",
            "expression": "extension.exists() != value.exists()",
            "xpath": "exists(f:extension)!=exists(f:*[starts-with(local-name(.), 'value')])",
            "source": "http://hl7.org/fhir/StructureDefinition/Extension"
          }
        ],
        "mapping": [
          {
            "identity": "rim",
            "map": "n/a"
          },
          {
            "identity": "rim",
            "map": "N/A"
          }
        ]
      },
      {
        "id": "Extension.extension:dateType",
        "path": "Extension.extension",
        "sliceName": "dateType",
        "short": "Whether the Date Period is 'Legal' , 'Operational' or 'System-Effective'",
        "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.",
        "comment": "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.",
        "alias": [
          "extensions",
          "user content"
        ],
        "min": 1,
        "max": "1",
        "base": {
          "path": "Element.extension",
          "min": 0,
          "max": "*"
        },
        "type": [
          {
            "code": "Extension"
          }
        ],
        "condition": [
          "ele-1"
        ],
        "constraint": [
          {
            "key": "ele-1",
            "severity": "error",
            "human": "All FHIR elements must have a @value or children",
            "expression": "hasValue() or (children().count() > id.count())",
            "xpath": "@value|f:*|h:div",
            "source": "http://hl7.org/fhir/StructureDefinition/Element"
          },
          {
            "key": "ext-1",
            "severity": "error",
            "human": "Must have either extensions or value[x], not both",
            "expression": "extension.exists() != value.exists()",
            "xpath": "exists(f:extension)!=exists(f:*[starts-with(local-name(.), 'value')])",
            "source": "http://hl7.org/fhir/StructureDefinition/Extension"
          }
        ],
        "mapping": [
          {
            "identity": "rim",
            "map": "n/a"
          },
          {
            "identity": "rim",
            "map": "N/A"
          }
        ]
      },
      {
        "id": "Extension.extension:dateType.id",
        "path": "Extension.extension.id",
        "representation": [
          "xmlAttr"
        ],
        "short": "Unique id for inter-element referencing",
        "definition": "Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.",
        "min": 0,
        "max": "1",
        "base": {
          "path": "Element.id",
          "min": 0,
          "max": "1"
        },
        "type": [
          {
            "extension": [
              {
                "url": "http://hl7.org/fhir/StructureDefinition/structuredefinition-fhir-type",
                "valueUrl": "string"
              }
            ],
            "code": "http://hl7.org/fhirpath/System.String"
          }
        ],
        "mapping": [
          {
            "identity": "rim",
            "map": "n/a"
          }
        ]
      },
      {
        "id": "Extension.extension:dateType.extension",
        "path": "Extension.extension.extension",
        "slicing": {
          "discriminator": [
            {
              "type": "value",
              "path": "url"
            }
          ],
          "description": "Extensions are always sliced by (at least) url",
          "rules": "open"
        },
        "short": "Additional content defined by implementations",
        "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.",
        "comment": "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.",
        "alias": [
          "extensions",
          "user content"
        ],
        "min": 0,
        "max": "0",
        "base": {
          "path": "Element.extension",
          "min": 0,
          "max": "*"
        },
        "type": [
          {
            "code": "Extension"
          }
        ],
        "condition": [
          "ele-1"
        ],
        "constraint": [
          {
            "key": "ele-1",
            "severity": "error",
            "human": "All FHIR elements must have a @value or children",
            "expression": "hasValue() or (children().count() > id.count())",
            "xpath": "@value|f:*|h:div",
            "source": "http://hl7.org/fhir/StructureDefinition/Element"
          },
          {
            "key": "ext-1",
            "severity": "error",
            "human": "Must have either extensions or value[x], not both",
            "expression": "extension.exists() != value.exists()",
            "xpath": "exists(f:extension)!=exists(f:*[starts-with(local-name(.), 'value')])",
            "source": "http://hl7.org/fhir/StructureDefinition/Extension"
          }
        ],
        "mapping": [
          {
            "identity": "rim",
            "map": "n/a"
          },
          {
            "identity": "rim",
            "map": "N/A"
          }
        ]
      },
      {
        "id": "Extension.extension:dateType.url",
        "path": "Extension.extension.url",
        "representation": [
          "xmlAttr"
        ],
        "short": "identifies the meaning of the extension",
        "definition": "Source of the definition for the extension code - a logical name or a URL.",
        "comment": "The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.",
        "min": 1,
        "max": "1",
        "base": {
          "path": "Extension.url",
          "min": 1,
          "max": "1"
        },
        "type": [
          {
            "extension": [
              {
                "url": "http://hl7.org/fhir/StructureDefinition/structuredefinition-fhir-type",
                "valueUrl": "uri"
              }
            ],
            "code": "http://hl7.org/fhirpath/System.String"
          }
        ],
        "fixedUri": "dateType",
        "mapping": [
          {
            "identity": "rim",
            "map": "N/A"
          }
        ]
      },
      {
        "id": "Extension.extension:dateType.value[x]",
        "path": "Extension.extension.value[x]",
        "short": "A ValueSet to identify the type of period.",
        "definition": "Value of extension - must be one of a constrained set of the data types (see [Extensibility](extensibility.html) for a list).",
        "min": 1,
        "max": "1",
        "base": {
          "path": "Extension.value[x]",
          "min": 0,
          "max": "1"
        },
        "type": [
          {
            "code": "Coding"
          }
        ],
        "condition": [
          "ele-1"
        ],
        "constraint": [
          {
            "key": "ele-1",
            "severity": "error",
            "human": "All FHIR elements must have a @value or children",
            "expression": "hasValue() or (children().count() > id.count())",
            "xpath": "@value|f:*|h:div",
            "source": "http://hl7.org/fhir/StructureDefinition/Element"
          }
        ],
        "binding": {
          "strength": "extensible",
          "description": "The type of period data.",
          "valueSet": "https://fhir.nhs.uk/England/ValueSet/England-PeriodType"
        },
        "mapping": [
          {
            "identity": "rim",
            "map": "n/a"
          },
          {
            "identity": "rim",
            "map": "N/A"
          }
        ]
      },
      {
        "id": "Extension.extension:period",
        "path": "Extension.extension",
        "sliceName": "period",
        "short": "The specific business related date or time period.",
        "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.",
        "comment": "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.",
        "alias": [
          "extensions",
          "user content"
        ],
        "min": 1,
        "max": "1",
        "base": {
          "path": "Element.extension",
          "min": 0,
          "max": "*"
        },
        "type": [
          {
            "code": "Extension"
          }
        ],
        "condition": [
          "ele-1"
        ],
        "constraint": [
          {
            "key": "ele-1",
            "severity": "error",
            "human": "All FHIR elements must have a @value or children",
            "expression": "hasValue() or (children().count() > id.count())",
            "xpath": "@value|f:*|h:div",
            "source": "http://hl7.org/fhir/StructureDefinition/Element"
          },
          {
            "key": "ext-1",
            "severity": "error",
            "human": "Must have either extensions or value[x], not both",
            "expression": "extension.exists() != value.exists()",
            "xpath": "exists(f:extension)!=exists(f:*[starts-with(local-name(.), 'value')])",
            "source": "http://hl7.org/fhir/StructureDefinition/Extension"
          }
        ],
        "mapping": [
          {
            "identity": "rim",
            "map": "n/a"
          },
          {
            "identity": "rim",
            "map": "N/A"
          }
        ]
      },
      {
        "id": "Extension.extension:period.id",
        "path": "Extension.extension.id",
        "representation": [
          "xmlAttr"
        ],
        "short": "Unique id for inter-element referencing",
        "definition": "Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.",
        "min": 0,
        "max": "1",
        "base": {
          "path": "Element.id",
          "min": 0,
          "max": "1"
        },
        "type": [
          {
            "extension": [
              {
                "url": "http://hl7.org/fhir/StructureDefinition/structuredefinition-fhir-type",
                "valueUrl": "string"
              }
            ],
            "code": "http://hl7.org/fhirpath/System.String"
          }
        ],
        "mapping": [
          {
            "identity": "rim",
            "map": "n/a"
          }
        ]
      },
      {
        "id": "Extension.extension:period.extension",
        "path": "Extension.extension.extension",
        "slicing": {
          "discriminator": [
            {
              "type": "value",
              "path": "url"
            }
          ],
          "description": "Extensions are always sliced by (at least) url",
          "rules": "open"
        },
        "short": "Additional content defined by implementations",
        "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.",
        "comment": "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.",
        "alias": [
          "extensions",
          "user content"
        ],
        "min": 0,
        "max": "0",
        "base": {
          "path": "Element.extension",
          "min": 0,
          "max": "*"
        },
        "type": [
          {
            "code": "Extension"
          }
        ],
        "condition": [
          "ele-1"
        ],
        "constraint": [
          {
            "key": "ele-1",
            "severity": "error",
            "human": "All FHIR elements must have a @value or children",
            "expression": "hasValue() or (children().count() > id.count())",
            "xpath": "@value|f:*|h:div",
            "source": "http://hl7.org/fhir/StructureDefinition/Element"
          },
          {
            "key": "ext-1",
            "severity": "error",
            "human": "Must have either extensions or value[x], not both",
            "expression": "extension.exists() != value.exists()",
            "xpath": "exists(f:extension)!=exists(f:*[starts-with(local-name(.), 'value')])",
            "source": "http://hl7.org/fhir/StructureDefinition/Extension"
          }
        ],
        "mapping": [
          {
            "identity": "rim",
            "map": "n/a"
          },
          {
            "identity": "rim",
            "map": "N/A"
          }
        ]
      },
      {
        "id": "Extension.extension:period.url",
        "path": "Extension.extension.url",
        "representation": [
          "xmlAttr"
        ],
        "short": "identifies the meaning of the extension",
        "definition": "Source of the definition for the extension code - a logical name or a URL.",
        "comment": "The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.",
        "min": 1,
        "max": "1",
        "base": {
          "path": "Extension.url",
          "min": 1,
          "max": "1"
        },
        "type": [
          {
            "extension": [
              {
                "url": "http://hl7.org/fhir/StructureDefinition/structuredefinition-fhir-type",
                "valueUrl": "uri"
              }
            ],
            "code": "http://hl7.org/fhirpath/System.String"
          }
        ],
        "fixedUri": "period",
        "mapping": [
          {
            "identity": "rim",
            "map": "N/A"
          }
        ]
      },
      {
        "id": "Extension.extension:period.value[x]",
        "path": "Extension.extension.value[x]",
        "short": "The date or time period.",
        "definition": "Value of extension - must be one of a constrained set of the data types (see [Extensibility](extensibility.html) for a list).",
        "min": 1,
        "max": "1",
        "base": {
          "path": "Extension.value[x]",
          "min": 0,
          "max": "1"
        },
        "type": [
          {
            "code": "Period"
          }
        ],
        "condition": [
          "ele-1"
        ],
        "constraint": [
          {
            "key": "ele-1",
            "severity": "error",
            "human": "All FHIR elements must have a @value or children",
            "expression": "hasValue() or (children().count() > id.count())",
            "xpath": "@value|f:*|h:div",
            "source": "http://hl7.org/fhir/StructureDefinition/Element"
          }
        ],
        "mapping": [
          {
            "identity": "rim",
            "map": "n/a"
          },
          {
            "identity": "rim",
            "map": "N/A"
          }
        ]
      },
      {
        "id": "Extension.url",
        "path": "Extension.url",
        "representation": [
          "xmlAttr"
        ],
        "short": "identifies the meaning of the extension",
        "definition": "Source of the definition for the extension code - a logical name or a URL.",
        "comment": "The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.",
        "min": 1,
        "max": "1",
        "base": {
          "path": "Extension.url",
          "min": 1,
          "max": "1"
        },
        "type": [
          {
            "extension": [
              {
                "url": "http://hl7.org/fhir/StructureDefinition/structuredefinition-fhir-type",
                "valueUrl": "uri"
              }
            ],
            "code": "http://hl7.org/fhirpath/System.String"
          }
        ],
        "fixedUri": "https://fhir.nhs.uk/England/StructureDefinition/Extension-England-TypedPeriod",
        "mapping": [
          {
            "identity": "rim",
            "map": "N/A"
          }
        ]
      },
      {
        "id": "Extension.value[x]",
        "path": "Extension.value[x]",
        "short": "Value of extension",
        "definition": "Value of extension - must be one of a constrained set of the data types (see [Extensibility](extensibility.html) for a list).",
        "min": 0,
        "max": "0",
        "base": {
          "path": "Extension.value[x]",
          "min": 0,
          "max": "1"
        },
        "type": [
          {
            "code": "base64Binary"
          },
          {
            "code": "boolean"
          },
          {
            "code": "canonical"
          },
          {
            "code": "code"
          },
          {
            "code": "date"
          },
          {
            "code": "dateTime"
          },
          {
            "code": "decimal"
          },
          {
            "code": "id"
          },
          {
            "code": "instant"
          },
          {
            "code": "integer"
          },
          {
            "code": "markdown"
          },
          {
            "code": "oid"
          },
          {
            "code": "positiveInt"
          },
          {
            "code": "string"
          },
          {
            "code": "time"
          },
          {
            "code": "unsignedInt"
          },
          {
            "code": "uri"
          },
          {
            "code": "url"
          },
          {
            "code": "uuid"
          },
          {
            "code": "Address"
          },
          {
            "code": "Age"
          },
          {
            "code": "Annotation"
          },
          {
            "code": "Attachment"
          },
          {
            "code": "CodeableConcept"
          },
          {
            "code": "Coding"
          },
          {
            "code": "ContactPoint"
          },
          {
            "code": "Count"
          },
          {
            "code": "Distance"
          },
          {
            "code": "Duration"
          },
          {
            "code": "HumanName"
          },
          {
            "code": "Identifier"
          },
          {
            "code": "Money"
          },
          {
            "code": "Period"
          },
          {
            "code": "Quantity"
          },
          {
            "code": "Range"
          },
          {
            "code": "Ratio"
          },
          {
            "code": "Reference"
          },
          {
            "code": "SampledData"
          },
          {
            "code": "Signature"
          },
          {
            "code": "Timing"
          },
          {
            "code": "ContactDetail"
          },
          {
            "code": "Contributor"
          },
          {
            "code": "DataRequirement"
          },
          {
            "code": "Expression"
          },
          {
            "code": "ParameterDefinition"
          },
          {
            "code": "RelatedArtifact"
          },
          {
            "code": "TriggerDefinition"
          },
          {
            "code": "UsageContext"
          },
          {
            "code": "Dosage"
          },
          {
            "code": "Meta"
          }
        ],
        "condition": [
          "ele-1"
        ],
        "constraint": [
          {
            "key": "ele-1",
            "severity": "error",
            "human": "All FHIR elements must have a @value or children",
            "expression": "hasValue() or (children().count() > id.count())",
            "xpath": "@value|f:*|h:div",
            "source": "http://hl7.org/fhir/StructureDefinition/Element"
          }
        ],
        "mapping": [
          {
            "identity": "rim",
            "map": "n/a"
          },
          {
            "identity": "rim",
            "map": "N/A"
          }
        ]
      }
    ]
  },
  "differential": {
    "element": [
      {
        "id": "Extension",
        "path": "Extension",
        "short": "This supports the recording of a period related to the specified date type.",
        "definition": "This supports the recording of a period related to the specified date type. The date/time period is carried along with a code to identify the type of period."
      },
      {
        "id": "Extension.extension",
        "path": "Extension.extension",
        "min": 2
      },
      {
        "id": "Extension.extension:dateType",
        "path": "Extension.extension",
        "sliceName": "dateType",
        "short": "Whether the Date Period is 'Legal' , 'Operational' or 'System-Effective'",
        "min": 1,
        "max": "1"
      },
      {
        "id": "Extension.extension:dateType.extension",
        "path": "Extension.extension.extension",
        "max": "0"
      },
      {
        "id": "Extension.extension:dateType.url",
        "path": "Extension.extension.url",
        "fixedUri": "dateType"
      },
      {
        "id": "Extension.extension:dateType.value[x]",
        "path": "Extension.extension.value[x]",
        "short": "A ValueSet to identify the type of period.",
        "min": 1,
        "type": [
          {
            "code": "Coding"
          }
        ],
        "binding": {
          "strength": "extensible",
          "description": "The type of period data.",
          "valueSet": "https://fhir.nhs.uk/England/ValueSet/England-PeriodType"
        }
      },
      {
        "id": "Extension.extension:period",
        "path": "Extension.extension",
        "sliceName": "period",
        "short": "The specific business related date or time period.",
        "min": 1,
        "max": "1"
      },
      {
        "id": "Extension.extension:period.extension",
        "path": "Extension.extension.extension",
        "max": "0"
      },
      {
        "id": "Extension.extension:period.url",
        "path": "Extension.extension.url",
        "fixedUri": "period"
      },
      {
        "id": "Extension.extension:period.value[x]",
        "path": "Extension.extension.value[x]",
        "short": "The date or time period.",
        "min": 1,
        "type": [
          {
            "code": "Period"
          }
        ]
      },
      {
        "id": "Extension.url",
        "path": "Extension.url",
        "fixedUri": "https://fhir.nhs.uk/England/StructureDefinition/Extension-England-TypedPeriod"
      },
      {
        "id": "Extension.value[x]",
        "path": "Extension.value[x]",
        "max": "0"
      }
    ]
  }
}