### Expand ValueSet

Source: https://loinc.org/fhir/index

Retrieves the expansion of a ValueSet resource. You can specify a version number as a suffix to the URL to get details from a previous LOINC version.

```APIDOC
## GET /ValueSet/$expand

### Description
Expands a ValueSet resource to show its members. Supports versioning by appending a version suffix to the URL.

### Method
GET

### Endpoint
`https://fhir.loinc.org/ValueSet/$expand`

### Query Parameters
- **url** (string) - Required - The URL of the ValueSet to expand. Can include a version suffix (e.g., `http://loinc.org/vs/LG51018-6-2.71`).

### Request Example
```
GET https://fhir.loinc.org/ValueSet/$expand?url=http://loinc.org/vs/LG51018-6-2.70
```

### Response
#### Success Response (200)
- **resourceType** (string) - "ValueSet"
- **url** (string) - The URL of the ValueSet.
- **version** (string) - The version of the ValueSet (if specified).
- **name** (string) - The name of the ValueSet.
- **status** (string) - The status of the ValueSet (e.g., "active").
- **expansion** (object) - Contains the expanded list of concepts.
  - **identifier** (string) - Identifier for the expansion.
  - **timestamp** (string) - Timestamp of the expansion.
  - **contains** (array) - An array of ValueSet components.
    - **system** (string) - The system URL (e.g., "http://loinc.org").
    - **code** (string) - The code of the concept.
    - **display** (string) - The display name of the concept.

#### Response Example
```json
{
  "resourceType": "ValueSet",
  "url": "http://loinc.org/vs/LG51018-6-2.70",
  "version": "2.70",
  "name": "SARS-CoV-2 serology tests",
  "status": "active",
  "expansion": {
    "identifier": "http://loinc.org/vs/LG51018-6?_format=application/fhir+json&_pretty=true",
    "timestamp": "2023-10-27T10:00:00Z",
    "contains": [
      {
        "system": "http://loinc.org",
        "code": "LG51018-6",
        "display": "SARS-CoV-2 serology tests"
      }
      // ... other concepts
    ]
  }
}
```
```

--------------------------------

### Get LOINC Term Information using $lookup

Source: https://loinc.org/fhir/index

Use the $lookup operation on the CodeSystem endpoint to retrieve details about individual LOINC terms, Parts, Answer Lists, or Answer strings. This operation takes the canonical LOINC URI and code as parameters.

```HTTP
https://fhir.loinc.org/CodeSystem/$lookup?system=http://loinc.org&code=4544-3
```

```HTTP
https://fhir.loinc.org/CodeSystem/$lookup?system=http://loinc.org&code=LP31755-9
```

```HTTP
https://fhir.loinc.org/CodeSystem/$lookup?system=http://loinc.org&code=LL1162-8
```

```HTTP
https://fhir.loinc.org/CodeSystem/$lookup?system=http://loinc.org&code=LA6751-7
```

--------------------------------

### FHIR $translate operation example for LOINC code 30657-1

Source: https://loinc.org/fhir/index

This example demonstrates using the FHIR '$translate' operation to find mappings for a specific LOINC code (30657-1). It shows how to retrieve translation information from the ConceptMap resource.

```HTTP
https://fhir.loinc.org/ConceptMap/$translate?system=http://loinc.org&code=30657-1
```

--------------------------------

### Retrieve ValueSet Definition

Source: https://loinc.org/fhir/index

Obtain the complete ValueSet resource definition, including metadata and criteria, by calling the ValueSet resource directly. This is useful for understanding the composition of a value set.

```HTTP
https://fhir.loinc.org/ValueSet/?url=http://loinc.org/vs/LL1162-8
```

```HTTP
https://fhir.loinc.org/ValueSet/LL1162-8
```

--------------------------------

### FHIR $translate operation example for LOINC code 11556-8

Source: https://loinc.org/fhir/index

This example shows how to use the FHIR '$translate' operation to find mappings for another specific LOINC code (11556-8). This operation is fundamental for querying concept mappings.

```HTTP
https://fhir.loinc.org/ConceptMap/$translate?system=http://loinc.org&code=11556-8
```

--------------------------------

### Expand ValueSet to List Terms using $expand

Source: https://loinc.org/fhir/index

Use the $expand operation on the ValueSet resource to retrieve only the list of terms within a given value set (value set expansion), excluding the metadata. This provides a concise list of included codes.

```HTTP
https://fhir.loinc.org/ValueSet/$expand?url=http://loinc.org/vs/LL1162-8
```

--------------------------------

### LOINC Coding Properties for System

Source: https://loinc.org/fhir/index

Details coding properties for describing the system from which data originates. This includes the core system identifier and its super-system if applicable, important for data lineage and context.

```json
{
        "code": "system-core",
        "uri": "http://loinc.org/property/system-core",
        "description": "The primary part of the System, i.e., without the super system",
        "type": "Coding"
      }, {
        "code": "super-system",
        "uri": "http://loinc.org/property/super-system",
        "description": "The super system part of the System, if present. The super system represents the source of the specimen when the source is someone or something other than the patient whose chart the result will be stored in. For example, fetus is the super system for measurements done on obstetric ultrasounds, because the fetus is being measured and that measurement is being recorded in the patient's (mother's) chart.",
        "type": "Coding"
      }
```

--------------------------------

### Get LOINC CodeSystem Properties

Source: https://loinc.org/fhir/index

Retrieve all specialized properties available for LOINC as a CodeSystem in FHIR using its canonical URI.

```APIDOC
## GET /CodeSystem/

### Description
Retrieves specialized properties for LOINC as a CodeSystem in FHIR.

### Method
GET

### Endpoint
`https://fhir.loinc.org/CodeSystem/`

### Query Parameters
- **url** (string) - Required - The canonical URI for LOINC, which is `http://loinc.org`.

### Request Example
```bash
GET https://fhir.loinc.org/CodeSystem/?url=http://loinc.org
```

### Response
#### Success Response (200)
Returns a FHIR Bundle resource containing the CodeSystem resource for LOINC, including its properties and filters.

- **resourceType** (string) - Indicates the resource type, which is 'Bundle'.
- **id** (string) - A unique identifier for the bundle.
- **meta** (object) - Metadata about the bundle, including the last updated timestamp.
- **type** (string) - The type of the bundle, typically 'searchset'.
- **total** (integer) - The total number of entries in the bundle.
- **link** (array) - Links related to the bundle, including a self-link.
- **entry** (array) - An array of bundle entries, where each entry contains a resource.
  - **fullUrl** (string) - The full URL of the resource.
  - **resource** (object) - The actual FHIR resource, which is a CodeSystem.
    - **resourceType** (string) - 'CodeSystem'.
    - **id** (string) - The ID of the CodeSystem resource.
    - **meta** (object) - Metadata for the CodeSystem resource.
    - **url** (string) - The canonical URL of the CodeSystem.
    - **identifier** (array) - Identifiers for the CodeSystem.
    - **version** (string) - The version of the CodeSystem.
    - **name** (string) - The name of the CodeSystem.
    - **title** (string) - A human-readable title for the CodeSystem.
    - **status** (string) - The status of the CodeSystem (e.g., 'active').
    - **experimental** (boolean) - Indicates if the CodeSystem is experimental.
    - **publisher** (string) - The publisher of the CodeSystem.
    - **contact** (array) - Contact information for the publisher.
    - **description** (string) - A description of the CodeSystem.
    - **copyright** (string) - Copyright information.
    - **caseSensitive** (boolean) - Whether the CodeSystem is case-sensitive.
    - **valueSet** (string) - A URL to the associated value set.
    - **hierarchyMeaning** (string) - The meaning of the hierarchy (e.g., 'is-a').
    - **compositional** (boolean) - Whether the CodeSystem is compositional.
    - **versionNeeded** (boolean) - Whether a version is needed.
    - **content** (string) - The content type of the CodeSystem (e.g., 'not-present').
    - **filter** (array) - Filters available for the CodeSystem.
    - **property** (array) - Properties defined for the CodeSystem.

#### Response Example
```json
{
  "resourceType": "Bundle",
  "id": "c0a14ee4-7d7f-417b-9f54-cfd0079fee15",
  "meta": {
    "lastUpdated": "2025-08-13T12:59:55.944+00:00"
  },
  "type": "searchset",
  "total": 14,
  "link": [
    {
      "relation": "self",
      "url": "https://fhir.loinc.org/CodeSystem/?_format=json&url=http%3A%2F%2Floinc.org"
    }
  ],
  "entry": [
    {
      "fullUrl": "https://fhir.loinc.org/CodeSystem/loinc-2.81",
      "resource": {
        "resourceType": "CodeSystem",
        "id": "loinc-2.81",
        "meta": {
          "versionId": "1",
          "lastUpdated": "2025-08-12T13:46:47.558+00:00",
          "source": "#4qQWv5QwJaqwagAH"
        },
        "url": "http://loinc.org",
        "identifier": [
          {
            "system": "urn:ietf:rfc:3986",
            "value": "urn:oid:2.16.840.1.113883.6.1"
          }
        ],
        "version": "2.81",
        "name": "LOINC",
        "title": "LOINC Code System",
        "status": "active",
        "experimental": false,
        "publisher": "Regenstrief Institute, Inc.",
        "contact": [
          {
            "telecom": [
              {
                "system": "url",
                "value": "http://loinc.org"
              }
            ]
          }
        ],
        "description": "LOINC is a freely available international standard for tests, measurements, and observations",
        "copyright": "This material contains content from LOINC (http://loinc.org). LOINC is copyright Regenstrief Institute, Inc. and the Logical Observation Identifiers Names and Codes (LOINC) Committee and is available at no cost under the license at http://loinc.org/license. LOINC® is a registered United States trademark of Regenstrief Institute, Inc.",
        "caseSensitive": false,
        "valueSet": "http://loinc.org/vs",
        "hierarchyMeaning": "is-a",
        "compositional": false,
        "versionNeeded": false,
        "content": "not-present",
        "filter": [
          {
            "code": "parent",
            "description": "Allows for the selection of a set of codes based on their appearance in the LOINC Component Hierarchy by System. Parent selects immediate parent only. For example, the code '79190-5' has the parent 'LP379670-5'",
            "operator": [
              "="
            ],
            "value": "A Part code"
          },
          {
            "code": "child",
            "description": "Allows for the selection of a set of codes based on their appearance in the LOINC Component Hierarchy by System. Child selects immediate children only. For example, the code 'LP379670-5' has the child '79190-5'. Only LOINC Parts have children; LOINC codes do not have any children because they are leaf nodes.",
            "operator": [
              "="
            ],
            "value": "A comma separated list of Part or LOINC codes"
          },
          {
            "code": "copyright",
            "description": "Allows for the inclusion or exclusion of LOINC codes that include 3rd party copyright notices. LOINC = only codes with a sole copyright by Regenstrief. 3rdParty = only codes with a 3rd party copyright in addition to the one from Regenstrief",
            "operator": [
              "="
            ],
            "value": "LOINC | 3rdParty"
          }
        ],
        "property": [
          {
            "code": "parent",
            "uri": "http://hl7.org/fhir/concept-properties#parent",
            "description": "A parent code in the Component Hierarchy by System",
            "type": "code"
          },
          {
            "code": "child",
            "uri": "http://hl7.org/fhir/concept-properties#child",
            "description": "A child code in the Component Hierarchy by System",
            "type": "code"
          },
          {
            "code": "COMPONENT",
            "uri": "http://loinc.org/property/COMPONENT",
            "description": "First major axis-component or analyte: Analyte Name, Analyte sub-class, Challenge",
            "type": "Coding"
          },
          {
            "code": "PROPERTY",
            "uri": "http://loinc.org/property/PROPERTY",
            "description": "Second major axis-property observed: Kind of Property (also called kind of quantity)",
            "type": "Coding"
          },
          {
            "code": "TIME_ASPCT",
            "uri": "http://loinc.org/property/TIME_ASPCT",
            "description": "Third major axis-timing of the measurement: Time Aspect (Point or moment in time vs. time interval)",
            "type": "Coding"
          },
          {
            "code": "SYSTEM",
            "uri": "http://loinc.org/property/SYSTEM",
            "description": "Fourth major axis-type of specimen or system: System (Sample) Type",
            "type": "Coding"
          },
          {
            "code": "SCALE_TYP",
            "uri": "http://loinc.org/property/SCALE_TYP",
            "description": "Fifth major axis-scale of measurement: Type of Scale",
            "type": "Coding"
          },
          {
            "code": "METHOD_TYP",
            "uri": "http://loinc.org/property/METHOD_TYP",
            "description": "Sixth major axis-method of measurement: Method Type",
            "type": "Coding"
          }
        ]
      }
    }
  ]
}
```

```

--------------------------------

### Retrieve PubChem terms to LOINC Parts ConceptMap

Source: https://loinc.org/fhir/index

This URL retrieves the ConceptMap for mapping PubChem terms back to LOINC Parts. This enables the analysis of chemical data within the context of laboratory measurements.

```HTTP
https://fhir.loinc.org/ConceptMap/?url=http://loinc.org/cm/pubchem-to-loinc-parts
```

--------------------------------

### LOINC ValueSet Resource

Source: https://loinc.org/fhir/index

Retrieves the definition of a LOINC ValueSet resource, including its metadata and definition criteria. This can be used to get all terms within extensional value sets.

```APIDOC
## GET ValueSet

### Description
Retrieves the full definition of a LOINC ValueSet resource.

### Method
GET

### Endpoint
/ValueSet

### Parameters
#### Query Parameters
- **url** (string) - Required - The URL of the ValueSet to retrieve, e.g., 'http://loinc.org/vs/LL1162-8'.

### Request Example
```
https://fhir.loinc.org/ValueSet/?url=http://loinc.org/vs/LL1162-8
```

### Response
#### Success Response (200)
- **ValueSet** (object) - The ValueSet resource containing metadata and definition criteria.

#### Response Example
```json
{
  "resourceType": "ValueSet",
  "id": "LL1162-8",
  "url": "http://loinc.org/vs/LL1162-8",
  "status": "active",
  "name": "Chemistry Panel",
  "expansion": {
    "contains": [
      {
        "system": "http://loinc.org",
        "code": "4544-3",
        "display": "Glucose measurement"
      }
    ]
  }
}
```
```

--------------------------------

### Retrieve ChEBI concepts to LOINC Parts ConceptMap

Source: https://loinc.org/fhir/index

This URL retrieves the ConceptMap for mapping ChEBI concepts back to LOINC Parts. This allows for the analysis of chemical data within the context of laboratory tests.

```HTTP
https://fhir.loinc.org/ConceptMap/?url=http://loinc.org/cm/chebi-to-loinc-parts
```

--------------------------------

### LOINC CodeSystem Properties

Source: https://loinc.org/fhir/index

This section details the properties available within the LOINC CodeSystem resource, including 'rad-guidance-for-object', 'rad-subject', 'document-kind', and others.

```APIDOC
## LOINC CodeSystem Properties

### Description
This endpoint provides information about the properties associated with the LOINC CodeSystem, which are used to categorize and filter LOINC codes.

### Method
GET

### Endpoint
/CodeSystem/loinc-2.78

### Parameters
#### Query Parameters
- **url** (string) - Optional - The canonical URL of the CodeSystem (e.g., 'http://loinc.org').
- **version** (string) - Optional - The version of the CodeSystem (e.g., '2.78').

### Request Example
```json
{
  "example": "GET https://fhir.loinc.org/CodeSystem/loinc-2.78?url=http://loinc.org&version=2.78"
}
```

### Response
#### Success Response (200)
- **resourceType** (string) - The type of the resource, which is 'CodeSystem'.
- **id** (string) - The unique identifier for the CodeSystem.
- **url** (string) - The canonical URL of the CodeSystem.
- **version** (string) - The version of the CodeSystem.
- **name** (string) - The name of the CodeSystem.
- **title** (string) - The human-readable title of the CodeSystem.
- **status** (string) - The status of the CodeSystem (e.g., 'active').
- **description** (string) - A description of the CodeSystem.
- **property** (array) - An array of property objects, each describing a property with 'code', 'description', 'operator', and 'value'.

#### Response Example
```json
{
  "example": "{\n  \"resourceType\": \"CodeSystem\",\n  \"id\": \"loinc-2.78\",\n  \"url\": \"http://loinc.org\",\n  \"version\": \"2.78\",\n  \"name\": \"LOINC\",\n  \"title\": \"LOINC Code System\",\n  \"status\": \"active\",\n  \"description\": \"LOINC is a freely available international standard for tests, measurements, and observations\",\n  \"property\": [\n    {\n      \"code\": \"parent\",\n      \"description\": \"Allows for the selection of a set of codes based on their appearance in the LOINC Component Hierarchy by System. Parent selects immediate parent only. For example, the code '79190-5' has the parent 'LP379670-5'\",\n      \"operator\": [ \"=\" ],\n      \"value\": \"A Part code\"\n    },\n    {\n      \"code\": \"child\",\n      \"description\": \"Allows for the selection of a set of codes based on their appearance in the LOINC Component Hierarchy by System. Child selects immediate children only. For example, the code 'LP379670-5' has the child '79190-5'. Only LOINC Parts have children; LOINC codes do not have any children because they are leaf nodes.\"\n    },\n    {\n      \"code\": \"copyright\",\n      \"description\": \"Allows for the inclusion or exclusion of LOINC codes that include 3rd party copyright notices. LOINC = only codes with a sole copyright by Regenstrief. 3rdParty = only codes with a 3rd party copyright in addition to the one from Regenstrief\"\n    }\n  ]\n}"
}
```
```

--------------------------------

### Find LOINC Term Relationships using $lookup

Source: https://loinc.org/fhir/index

Explore relationships between LOINC terms and Parts within the LOINC Component Hierarchy by System using the $lookup operation with 'parent' and 'child' properties. LOINC Parts have a single parent and multiple children, while LOINC terms have parents but no children.

```HTTP
https://fhir.loinc.org/CodeSystem/$lookup?system=http://loinc.org&code=LP14542-2&&property=parent
```

```HTTP
https://fhir.loinc.org/CodeSystem/$lookup?system=http://loinc.org&code=LP28725-7&&property=parent
```

```HTTP
https://fhir.loinc.org/CodeSystem/$lookup?system=http://loinc.org&code=LP203649-1&&property=child
```

```HTTP
https://fhir.loinc.org/CodeSystem/$lookup?system=http://loinc.org&code=LP31448-1&&property=child
```

```HTTP
https://fhir.loinc.org/CodeSystem/$lookup?system=http://loinc.org&code=30064-0&&property=parent
```

```HTTP
https://fhir.loinc.org/CodeSystem/$lookup?system=http://loinc.org&code=79207-7&&property=parent
```

--------------------------------

### Retrieve a specific version of ConceptMap (loinc-parts-to-rxnorm 2.69)

Source: https://loinc.org/fhir/index

This URL demonstrates how to retrieve a specific version of a ConceptMap resource, in this case, 'loinc-parts-to-rxnorm' version 2.69. Versioning is crucial for maintaining historical accuracy of mappings.

```HTTP
https://fhir.loinc.org/ConceptMap/loinc-parts-to-rxnorm-2.69
```

--------------------------------

### Retrieve LOINC Parts to RxNorm terms ConceptMap

Source: https://loinc.org/fhir/index

This URL retrieves the ConceptMap for mapping LOINC Parts to RxNorm terms. This is crucial for linking detailed laboratory observations to pharmaceutical concepts.

```HTTP
https://fhir.loinc.org/ConceptMap/?url=http://loinc.org/cm/loinc-parts-to-rxnorm
```

--------------------------------

### Retrieve LOINC Parts to ChEBI concepts ConceptMap

Source: https://loinc.org/fhir/index

This URL retrieves the ConceptMap for mapping LOINC Parts to ChEBI concepts. This is useful for linking laboratory measurements to chemical entities.

```HTTP
https://fhir.loinc.org/ConceptMap/?url=http://loinc.org/cm/loinc-parts-to-chebi
```

--------------------------------

### Retrieve Specific CodeSystem Versions using $lookup

Source: https://loinc.org/fhir/index

Access previous versions of LOINC concepts by specifying a LOINC version identifier (e.g., 2.69) in the $lookup request. This is useful for historical data analysis.

```HTTP
https://fhir.loinc.org/CodeSystem/$lookup?system=http://loinc.org&code=LP14542-2&version=2.71
```

```HTTP
https://fhir.loinc.org/CodeSystem/$lookup?system=http://loinc.org&code=96595-4&version=2.69
```

```HTTP
https://fhir.loinc.org/CodeSystem/$lookup?system=http://loinc.org&code=96595-4&version=2.70
```

```HTTP
https://fhir.loinc.org/CodeSystem/$lookup?system=http://loinc.org&code=99463-2&version=2.71
```

--------------------------------

### Retrieve RxNorm terms to LOINC Parts ConceptMap

Source: https://loinc.org/fhir/index

This URL retrieves the ConceptMap for mapping RxNorm terms back to LOINC Parts. This allows for the analysis of pharmaceutical data using LOINC's detailed structure.

```HTTP
https://fhir.loinc.org/ConceptMap/?url=http://loinc.org/cm/rxnorm-to-loinc-parts
```

--------------------------------

### Versioning and Designations

Source: https://loinc.org/fhir/index

Information on how to reference specific versions of LOINC resources and the use of designations for translations and alternate names.

```APIDOC
## Versioning and Designations

### Versioning

**Description**: As of April 2022, LOINC's Terminology Service supports previous versions of `CodeSystem`, `ValueSet`, and `ConceptMap` resources. Requests without a specified version return the current version.

**Usage**: Reference a particular LOINC version as part of requests to these API endpoints. Versions 2.69 through current are available.

### Designations

**Description**: Designations within FHIR are used to provide non-English translations and alternate names for concepts. LOINC's Linguistic Variants are provided as designations.

**Availability**: Automatically returned on `CodeSystem $lookup` and `ValueSet $expand` operations. Includes translations, Consumer Names, and Short Names.

**Note**: Consumer Names have a disclaimer regarding their maturity and use.
```

--------------------------------

### Retrieve LOINC Parts to PubChem terms ConceptMap

Source: https://loinc.org/fhir/index

This URL retrieves the ConceptMap for mapping LOINC Parts to PubChem terms. This is useful for integrating laboratory data with chemical compound information.

```HTTP
https://fhir.loinc.org/ConceptMap/?url=http://loinc.org/cm/loinc-parts-to-pubchem
```

--------------------------------

### Retrieve IEEE device codes to LOINC ConceptMap

Source: https://loinc.org/fhir/index

This URL retrieves the ConceptMap resource that maps IEEE 11073-10101 device codes back to LOINC terms. This is essential for translating device-related codes into a more general clinical context.

```HTTP
https://fhir.loinc.org/ConceptMap/?url=http://loinc.org/cm/ieee-11073-10101-to-loinc
```

--------------------------------

### Retrieve LOINC to IEEE device codes ConceptMap

Source: https://loinc.org/fhir/index

This URL retrieves the ConceptMap resource that maps LOINC terms to IEEE 11073-10101 device codes. It's useful for interoperability between LOINC and device-specific terminologies.

```HTTP
https://fhir.loinc.org/ConceptMap/?url=http://loinc.org/cm/loinc-to-ieee-11073-10101
```

--------------------------------

### Retrieve PhenX concepts to LOINC ConceptMap

Source: https://loinc.org/fhir/index

This URL retrieves the ConceptMap for mapping PhenX concepts back to LOINC terms. This helps in analyzing phenotypic data within the broader LOINC framework.

```HTTP
https://fhir.loinc.org/ConceptMap/?url=http://loinc.org/cm/phenx-to-loinc
```

--------------------------------

### LOINC Properties and Filters

Source: https://loinc.org/fhir/index

Details on available properties and filters for searching and querying LOINC codes. This includes information on how to filter by parent/child relationships, copyright, and other attributes.

```APIDOC
## LOINC Properties and Filters

### Description
This section describes the properties and filters available for querying the LOINC terminology.

### Properties
- **parent** (code): A parent code in the Component Hierarchy by System.
- **child** (code): A child code in the Component Hierarchy by System.
- **COMPONENT** (Coding): Analyte Name, Analyte sub-class, Challenge.
- **PROPERTY** (Coding): Kind of Property (also called kind of quantity).
- **TIME_ASPCT** (Coding): Time Aspect (Point or moment in time vs. time interval).
- **SYSTEM** (Coding): Type of specimen or system (Sample) Type.
- **SCALE_TYP** (Coding): Type of Scale.
- **METHOD_TYP** (Coding): Type of Method.
- **CLASS** (Coding): Category of the LOINC code.
- **document-type-of-service** (Coding): Characterizes the kind of service or activity provided.
- **answers-for** (Coding): A LOINC Code for which this answer list is used.

### Filters
- **parent** (string): Allows for the selection of a set of codes based on their appearance in the LOINC Component Hierarchy by System. Parent selects immediate parent only.
  - **Operator**: =
  - **Value**: A Part code
- **child** (string): Allows for the selection of a set of codes based on their appearance in the LOINC Component Hierarchy by System. Child selects immediate children only.
  - **Operator**: =
  - **Value**: A comma separated list of Part or LOINC codes
- **copyright** (string): Allows for the inclusion or exclusion of LOINC codes that include 3rd party copyright notices.
  - **Operator**: =
  - **Value**: LOINC | 3rdParty
```

--------------------------------

### LOINC FHIR CodeSystem Resource

Source: https://loinc.org/fhir/index

Details on the LOINC CodeSystem resource, its properties, and how to access LOINC codes, parts, and answer lists.

```APIDOC
# CodeSystem

**Description**: The CodeSystem resource specifies a set of codes drawn from one or more code systems. LOINC's representation extends FHIR to include LOINC-specific features.

### LOINC Codes

**Example Identifier**: `21176-3`

### LOINC Parts

**Example Identifier**: `LP31755-9`

### LOINC Answer Lists

**Example Identifier**: `LL715-4`

### LOINC Answers

**Example Identifier**: `LA11165-0`

### Properties

**Description**: As of the March 2023 TS update, all LOINC fields exist as CodeSystem Properties. This includes general properties and LOINC-specific ones like `VersionFirstReleased`, `COMPONENT`, `ORDER_OBS`, `CLASSTYPE`.

**Endpoint**: Access via `$lookup` operation on the CodeSystem resource.
```

--------------------------------

### Retrieve LOINC Parts to NCBI ClinVar concepts ConceptMap

Source: https://loinc.org/fhir/index

This URL retrieves the ConceptMap for mapping LOINC Parts to NCBI ClinVar concepts. This is important for correlating laboratory findings with genetic variation data.

```HTTP
https://fhir.loinc.org/ConceptMap/?url=http://loinc.org/cm/loinc-parts-to-ncbi-clinvar
```

--------------------------------

### LOINC Code System Information

Source: https://loinc.org/fhir/index

Retrieves information about the LOINC CodeSystem, including its version, publisher, and copyright details. This endpoint is useful for understanding the source and licensing of LOINC codes.

```APIDOC
## GET /CodeSystem/loinc-2.80

### Description
Retrieves detailed information about the LOINC CodeSystem, including its version, publisher, and copyright information. This endpoint is essential for understanding the source and licensing of LOINC codes used within the FHIR system.

### Method
GET

### Endpoint
/CodeSystem/loinc-2.80

### Parameters
#### Path Parameters
- **id** (string) - Required - The logical ID of the CodeSystem, which is 'loinc-2.80' for the LOINC 2.80 version.

### Request Example
```json
{
  "example": "GET https://fhir.loinc.org/CodeSystem/loinc-2.80"
}
```

### Response
#### Success Response (200)
- **resourceType** (string) - The type of the resource, which is 'CodeSystem'.
- **id** (string) - The logical ID of the CodeSystem.
- **url** (string) - The canonical URL for the CodeSystem.
- **identifier** (array) - A list of business identifiers for the CodeSystem.
- **version** (string) - The version of the CodeSystem.
- **name** (string) - A machine-friendly name for the CodeSystem.
- **title** (string) - A human-friendly name for the CodeSystem.
- **status** (string) - The status of the CodeSystem (e.g., active, draft).
- **experimental** (boolean) - Indicates if the CodeSystem is for experimental use.
- **publisher** (string) - The name of the publisher of the CodeSystem.
- **contact** (array) - Contact details for the publisher.
- **description** (string) - A detailed description of the CodeSystem.
- **copyright** (string) - Information about the copyright and licensing of the CodeSystem.
- **caseSensitive** (boolean) - Indicates whether the code system is case sensitive.
- **valueSet** (string) - A link to the value set that describes the codes in this code system.
- **hierarchyMeaning** (string) - Indicates the meaning of the hierarchy relationship in the code system.
- **compositional** (boolean) - Indicates whether the code system defines codes by composition.
- **versionNeeded** (boolean) - Indicates whether a version is needed for the code system.
- **content** (string) - Indicates the content of the code system (e.g., not-present).
- **filter** (array) - A list of filters that can be applied to the code system.

#### Response Example
```json
{
  "resourceType": "CodeSystem",
  "id": "loinc-2.80",
  "meta": {
    "versionId": "1",
    "lastUpdated": "2025-02-26T18:46:28.769+00:00",
    "source": "#QM1tSoUOm3F7exkv"
  },
  "url": "http://loinc.org",
  "identifier": [
    {
      "system": "urn:ietf:rfc:3986",
      "value": "urn:oid:2.16.840.1.113883.6.1"
    }
  ],
  "version": "2.80",
  "name": "LOINC",
  "title": "LOINC Code System",
  "status": "active",
  "experimental": false,
  "publisher": "Regenstrief Institute, Inc.",
  "contact": [
    {
      "telecom": [
        {
          "system": "url",
          "value": "http://loinc.org"
        }
      ]
    }
  ],
  "description": "LOINC is a freely available international standard for tests, measurements, and observations",
  "copyright": "This material contains content from LOINC (http://loinc.org). LOINC is copyright Regenstrief Institute, Inc. and the Logical Observation Identifiers Names and Codes (LOINC) Committee and is available at no cost under the license at http://loinc.org/license. LOINC® is a registered United States trademark of Regenstrief Institute, Inc.",
  "caseSensitive": false,
  "valueSet": "http://loinc.org/vs",
  "hierarchyMeaning": "is-a",
  "compositional": false,
  "versionNeeded": false,
  "content": "not-present",
  "filter": [
    {
      "code": "parent",
      "description": "Allows for the selection of a set of codes based on their appearance in the LOINC Component Hierarchy by System. Parent selects immediate parent only. For example, the code '79190-5' has the parent 'LP379670-5'",
      "operator": [
        "="
      ],
      "value": "A Part code"
    },
    {
      "code": "child",
      "description": "Allows for the selection of a set of codes based on their appearance in the LOINC Component Hierarchy by System. Child selects immediate children only.",
      "operator": [
        "="
      ],
      "value": "A Part code"
    }
  ]
}
```
```

--------------------------------

### Retrieve NCBI ClinVar concepts to LOINC Parts ConceptMap

Source: https://loinc.org/fhir/index

This URL retrieves the ConceptMap for mapping NCBI ClinVar concepts back to LOINC Parts. This enables the analysis of genetic variant data in relation to laboratory tests.

```HTTP
https://fhir.loinc.org/ConceptMap/?url=http://loinc.org/cm/ncbi-clinvar-to-loinc-parts
```

--------------------------------

### Retrieve LOINC to PhenX concepts ConceptMap

Source: https://loinc.org/fhir/index

This URL retrieves the ConceptMap for mapping LOINC terms to PhenX concepts. This facilitates the standardization of phenotypic data.

```HTTP
https://fhir.loinc.org/ConceptMap/?url=http://loinc.org/cm/loinc-to-phenx
```

--------------------------------

### Retrieve NCBI Taxonomy concepts to LOINC Parts ConceptMap

Source: https://loinc.org/fhir/index

This URL retrieves the ConceptMap for mapping NCBI Taxonomy concepts back to LOINC Parts. This enables the analysis of taxonomic data in relation to laboratory tests.

```HTTP
https://fhir.loinc.org/ConceptMap/?url=http://loinc.org/cm/ncbi-taxonomy-to-loinc-parts
```

--------------------------------

### Retrieve CMS LT-PAC assessment concepts (OASIS) to LOINC ConceptMap

Source: https://loinc.org/fhir/index

This URL retrieves the ConceptMap for mapping CMS LT-PAC assessment concepts (OASIS) back to LOINC terms. This enables detailed analysis of OASIS data using LOINC.

```HTTP
https://fhir.loinc.org/ConceptMap/?url=http://loinc.org/cm/cms-oasis-to-loinc
```