# US Core Simple Observation Profile - US Core Implementation Guide v8.0.1

* [**Table of Contents**](toc.md)
* [**Artifacts Summary**](artifacts.md)
* **US Core Simple Observation Profile**

## Resource Profile: US Core Simple Observation Profile 

| | | |
| :--- | :--- | :--- |
| *Official URL*:http://hl7.org/fhir/us/core/StructureDefinition/us-core-simple-observation | *Version*:8.0.1 | |
| * Standards status: *[Trial-use](http://hl7.org/fhir/R4/versions.html#std-process) | [Maturity Level](http://hl7.org/fhir/versions.html#maturity): 3 | *Computable Name*:USCoreSimpleObservationProfile |
| *Other Identifiers:*OID:2.16.840.1.113883.4.642.40.2.42.59 | | |
| **Copyright/Legal**: Used by permission of HL7 International, all rights reserved Creative Commons License | | |

 
The US Core Simple Observation Profile inherits from the FHIR [Observation](https://hl7.org/fhir/R4/observation.html) resource; refer to it for scope and usage definitions. This US Core FHIR Profile captures any "simple" observations not covered by other US Core Observation profiles. It represents any observation not classified as vital signs, laboratory, imaging, or other specific observation types. This profile sets minimum expectations for the Observation resource to record, search, and retrieve observations such as a clinical observation or assertion about patient health status or other general observations. It specifies which core elements, extensions, vocabularies, and value sets **SHALL** be present and constrains how the elements are used. Providing the floor for standards development for specific use cases promotes interoperability and adoption. 

**Example Usage Scenarios:**

The following are example usage scenarios for this profile:

* Query for clinical observations or assessments about a patient's health status.
* [Record or update](us-core-roadmap.md#future-candidate-requirements-under-consideration) clinical observations or assessments about a patient's health status.

### Mandatory and Must Support Data Elements

The following data elements must always be present ([Mandatory](must-support.md) definition) or must be supported if the data is present in the sending system ([Must Support](must-support.md) definition). They are presented below in a simple human-readable explanation. Profile specific guidance and examples are provided as well. The [Formal Views](#profile) below provides the formal summary, definitions, and terminology requirements.

**Each Observation Must Have:**

1. a status
1. a category code*
1. a code
1. a patient

**Each Observation Must Support:**

1. a time indicating when the observation was made
1. who answered the questions (in other words, a performer)*
1. a value

**Additional USCDI Requirements:**

This [Additional USCDI Requirements](must-support.md#additional-uscdi-requirements) element is not Mandatory or Must Support but is required for ASTP Health IT certification testing and is included in the formal definition of the profile and the Observation examples.

1. a screening and assessments category code*
1. references to an associated survey, assessment, or screening tool*

*see guidance below

**Profile Specific Implementation Guidance:**

* The codes can be from LOINC or SNOMED CT.
* The value for these types of observations may be: 
* a string
* a code
* a "qualifier" confirming or refuting a statement about findings in code. For example: **code**: Transport too expensive (SNOMED CT: 160695008)
 **value**: true
 
* *At a minimum, Certifying Systems **SHALL** support, the [US Core Screening Assessment Observation Category](ValueSet-us-core-screening-assessment-observation-category.md) codes, **SHOULD** support the other [US Core Simple Observation Category](ValueSet-us-core-simple-observation-category.md) codes, and **MAY** support other categories.
* *An Observation without a value, **SHALL** include a reason why the data is absent **unless** there are 1) component observations, or 2) reporting panel observations using `Observation.hasMember`. 
* For further guidance, see the [Observation Grouping](http://hl7.org/fhir/R4/observation.html#obsgrouping) section in FHIR Specification.
* Systems that never provide an observation without a value are not required to support `Observation.dataAbsentReason`.
 
* *An `Observation.component` without a value, **SHALL** include a reason why the data is absent. 
* Systems that never provide a component observation without a component value are not required to support `Observation.component.dataAbsentReason`.
 
* See the [Screening and Assessments](screening-and-assessments.md) guidance page for how this profile can represent "clinical judgments". 
* *Observations formally part of an assessment tool or survey **SHOULD** use the [US Core Observation Screening Assessment Profile](StructureDefinition-us-core-observation-screening-assessment.md). However, an assertion or determination derived from screening and assessment tools **SHOULD** reference them using `Observation.derivedFrom`.
 

* *The profile elements `Observation.performer and Observation.device` communicate the [individual level provenance](basic-provenance.md#individual-level-provenance) author data corresponding to the U.S. Core Data for Interoperability (USCDI) Provenance Author Data Elements.
* *Although none of the `Observation.derivedFrom` [referenced target profiles are flagged as **Must Support**](must-support.md#must-support---resource-references), Certifying System **SHALL** support at least one of them. Client Applications **SHALL** support all.

**Usages:**

* Examples for this Profile: [Observation/alcohol-use-status](Observation-alcohol-use-status.md), [Observation/alcoholic-drinks-per-day](Observation-alcoholic-drinks-per-day.md), [Observation/exercise-per-day](Observation-exercise-per-day.md), [Observation/exercise-per-week](Observation-exercise-per-week.md)... Show 5 more, [Observation/simple-observation-cognitive-status](Observation-simple-observation-cognitive-status.md), [Observation/simple-observation-disability-status](Observation-simple-observation-disability-status.md), [Observation/simple-observation-functional-status](Observation-simple-observation-functional-status.md), [Observation/simple-observation-sdoh](Observation-simple-observation-sdoh.md) and [Observation/substance-use-status](Observation-substance-use-status.md)
* CapabilityStatements using this Profile: [US Core Client CapabilityStatement](CapabilityStatement-us-core-client.md) and [US Core Server CapabilityStatement](CapabilityStatement-us-core-server.md)

You can also check for [usages in the FHIR IG Statistics](https://packages2.fhir.org/xig/hl7.fhir.us.core|current/StructureDefinition/us-core-simple-observation)

**Changes since version 7.0.0:**

* The data elements list has changed

* One or more text definitions, invariants or bindings have changed

### Formal Views of Profile Content

 [Description of Profiles, Differentials, Snapshots and how the different presentations work](http://build.fhir.org/ig/FHIR/ig-guidance/readingIgs.html#structure-definitions). 

 

Other representations of profile: [CSV](StructureDefinition-us-core-simple-observation.csv), [Excel](StructureDefinition-us-core-simple-observation.xlsx), [Schematron](StructureDefinition-us-core-simple-observation.sch) 

### Notes:

-------

**Quick Start**  

-------

Below is an overview of the required Server RESTful FHIR interactions for this profile - for example, search and read operations - when supporting the US Core interactions to access this profile's information (Profile Support + Interaction Support). Note that systems that support only US Core Profiles (Profile Only Support) are not required to support these interactions. See the [US Core Server CapabilityStatement](CapabilityStatement-us-core-server.md) for a complete list of supported RESTful interactions for this IG.

* See the [Scopes Format](scopes.md#scopes-format) section for a description of the SMART scopes syntax.
* See the [Search Syntax](general-guidance.md#search-syntax) section for a description of the US Core search syntax.
* See the [General Requirements](general-requirements.md) section for additional rules and expectations when a Server requires status parameters.
* See the [General Guidance](general-guidance.md) section for additional guidance on searching for multiple patients.

#### US Core Scopes

Servers providing access to assessment data **SHALL** support these [US Core SMART Scopes](scopes.md#smart-scopes):

* [resource level scopes](http://hl7.org/fhir/smart-app-launch/STU2.2/scopes-and-launch-context.html#scopes-for-requesting-clinical-data): `<patient|user|system>/Observation.rs`
* [granular scopes](http://hl7.org/fhir/smart-app-launch/STU2.2/scopes-and-launch-context.html#finer-grained-resource-constraints-using-search-parameters): `<patient|user|system>/Observation.rs?category=http://hl7.org/fhir/us/core/CodeSystem/us-core-category|sdoh`

#### Mandatory Search Parameters:

The following search parameters and search parameter combinations SHALL be supported:

1. **SHALL** support searching using the combination of the **[`patient`](SearchParameter-us-core-observation-patient.md)** and **[`category`](SearchParameter-us-core-observation-category.md)** search parameters:`GET [base]/Observation?patient={Type/}[id]&category=http://terminology.hl7.org/CodeSystem/observation-category|laboratory`Example:
1. GET [base]/Observation?patient=1134281&amp;category=social-history
**Implementation Notes:** Fetches a bundle of all Observation resources for the specified patient and a category code = `laboratory` ([how to search by reference](http://hl7.org/fhir/R4/search.html#reference) and [how to search by token](http://hl7.org/fhir/R4/search.html#token))
1. **SHALL**support searching using the combination of the**[`patient`](SearchParameter-us-core-observation-patient.md)**and**[`code`](SearchParameter-us-core-observation-code.md)**search parameters:
* including optional support for **OR** search on `code` (e.g.`code={system|}[code],{system|}[code],...`)
`GET [base]/Observation?patient={Type/}[id]&code={system|}[code]{,{system|}[code],...}`Example:
1. GET [base]/Observation?patient=1134281&amp;code=http://loinc.org|
**Implementation Notes:** Fetches a bundle of all Observation resources for the specified patient and observation code(s). SHOULD support search by multiple report codes. The Observation `code` parameter searches `Observation.code only. ([how to search by reference](http://hl7.org/fhir/R4/search.html#reference) and [how to search by token](http://hl7.org/fhir/R4/search.html#token))
1. **SHALL**support searching using the combination of the**[`patient`](SearchParameter-us-core-observation-patient.md)**and**[`category`](SearchParameter-us-core-observation-category.md)**and**[`date`](SearchParameter-us-core-observation-date.md)**search parameters:
* including support for these `date` comparators: `gt,lt,ge,le`
* including optional support for **AND** search on `date` (e.g.`date=[date]&date=[date]]&...`)
`GET [base]/Observation?patient={Type/}[id]&category=http://terminology.hl7.org/CodeSystem/observation-category|laboratory&date={gt|lt|ge|le}[date]{&date={gt|lt|ge|le}[date]&...}`Example:
1. GET [base]Observation?patient=555580&category=social-history&date=ge2018-03-14T00:00:00Z
**Implementation Notes:** Fetches a bundle of all Observation resources for the specified patient and date and a category code = `laboratory` ([how to search by reference](http://hl7.org/fhir/R4/search.html#reference) and [how to search by token](http://hl7.org/fhir/R4/search.html#token) and [how to search by date](http://hl7.org/fhir/R4/search.html#date))

#### Optional Search Parameters:

The following search parameter combinations **SHOULD** be supported:

1. **SHOULD**support searching using the combination of the**[`patient`](SearchParameter-us-core-observation-patient.md)**and**[`category`](SearchParameter-us-core-observation-category.md)**and**[`status`](SearchParameter-us-core-observation-status.md)**search parameters:
* including support for **OR** search on `status` (e.g.`status={system|}[code],{system|}[code],...`)
`GET [base]/Observation?patient={Type/}[id]&category=http://terminology.hl7.org/CodeSystem/observation-category|laboratory&status={system|}[code]{,{system|}[code],...}`Example:
1. GET [base]/Observation?patient=1134281&category=social-history&status=final
**Implementation Notes:** Fetches a bundle of all Observation resources for the specified patient and category = `laboratory` and status ([how to search by reference](http://hl7.org/fhir/R4/search.html#reference) and [how to search by token](http://hl7.org/fhir/R4/search.html#token))
1. **SHOULD**support searching using the combination of the**[`patient`](SearchParameter-us-core-observation-patient.md)**and**[`category`](SearchParameter-us-core-observation-category.md)**and**[`_lastUpdated`](SearchParameter-us-core-observation-lastupdated.md)**search parameters:
* including support for these `_lastUpdated` comparators: `gt,lt,ge,le`
* including optional support for **AND** search on `_lastUpdated` (e.g.`_lastUpdated=[date]&_lastUpdated=[date]]&...`)
`GET [base]/Observation?patient={Type/}[id]&category={system|}[code]&_lastUpdated={gt|lt|ge|le}[date]{&_lastUpdated={gt|lt|ge|le}[date]&...}`Example:
1. GET [base]Observation?patient=555580&social-history&_lastUpdated=ge2024-01-01T00:00:00Z
**Implementation Notes:** Fetches a bundle of all Observation resources for the specified patient and category and _lastUpdated. See the US Core General Guidance page for [Searching Using lastUpdated](general-guidance.md#searching-using-lastupdated). ([how to search by reference](http://hl7.org/fhir/R4/search.html#reference) and [how to search by token](http://hl7.org/fhir/R4/search.html#token) and [how to search by date](http://hl7.org/fhir/R4/search.html#date))
1. **SHOULD**support searching using the combination of the**[`patient`](SearchParameter-us-core-observation-patient.md)**and**[`code`](SearchParameter-us-core-observation-code.md)**and**[`date`](SearchParameter-us-core-observation-date.md)**search parameters:
* including optional support for **OR** search on `code` (e.g.`code={system|}[code],{system|}[code],...`)
* including support for these `date` comparators: `gt,lt,ge,le`
* including optional support for **AND** search on `date` (e.g.`date=[date]&date=[date]]&...`)
`GET [base]/Observation?patient={Type/}[id]&code={system|}[code]{,{system|}[code],...}&date={gt|lt|ge|le}[date]{&date={gt|lt|ge|le}[date]&...}`Example:
1. GET [base]Observation?patient=555580&code=http://loinc.org|&date=ge2019-01-01T00:00:00Z
**Implementation Notes:** Fetches a bundle of all Observation resources for the specified patient and date and report code(s). SHOULD support search by multiple report codes. ([how to search by reference](http://hl7.org/fhir/R4/search.html#reference) and [how to search by token](http://hl7.org/fhir/R4/search.html#token) and [how to search by date](http://hl7.org/fhir/R4/search.html#date))



## Resource Content

```json
{
  "resourceType" : "StructureDefinition",
  "id" : "us-core-simple-observation",
  "extension" : [{
    "url" : "http://hl7.org/fhir/StructureDefinition/structuredefinition-wg",
    "valueCode" : "cgp"
  },
  {
    "url" : "http://hl7.org/fhir/StructureDefinition/structuredefinition-fmm",
    "valueInteger" : 3,
    "_valueInteger" : {
      "extension" : [{
        "url" : "http://hl7.org/fhir/StructureDefinition/structuredefinition-conformance-derivedFrom",
        "valueCanonical" : "http://hl7.org/fhir/us/core/ImplementationGuide/hl7.fhir.us.core"
      }]
    }
  },
  {
    "url" : "http://hl7.org/fhir/StructureDefinition/structuredefinition-standards-status",
    "valueCode" : "trial-use",
    "_valueCode" : {
      "extension" : [{
        "url" : "http://hl7.org/fhir/StructureDefinition/structuredefinition-conformance-derivedFrom",
        "valueCanonical" : "http://hl7.org/fhir/us/core/ImplementationGuide/hl7.fhir.us.core"
      }]
    }
  }],
  "url" : "http://hl7.org/fhir/us/core/StructureDefinition/us-core-simple-observation",
  "identifier" : [{
    "system" : "urn:ietf:rfc:3986",
    "value" : "urn:oid:2.16.840.1.113883.4.642.40.2.42.59"
  }],
  "version" : "8.0.1",
  "name" : "USCoreSimpleObservationProfile",
  "title" : "US Core Simple Observation Profile",
  "status" : "active",
  "date" : "2024-11-16",
  "publisher" : "HL7 International / Cross-Group Projects",
  "contact" : [{
    "name" : "HL7 International / Cross-Group Projects",
    "telecom" : [{
      "system" : "url",
      "value" : "http://www.hl7.org/Special/committees/cgp"
    },
    {
      "system" : "email",
      "value" : "cgp@lists.HL7.org"
    }]
  }],
  "description" : "The US Core Simple Observation Profile inherits from the FHIR [Observation](https://hl7.org/fhir/R4/observation.html) resource; refer to it for scope and usage definitions. This US Core FHIR Profile captures any \"simple\" observations not covered by other US Core Observation profiles. It represents any observation not classified as vital signs, laboratory,  imaging, or other specific observation types. This profile sets minimum expectations for the Observation resource to record, search, and retrieve observations such as a clinical observation or assertion about patient health status or other general observations. It specifies which core elements, extensions, vocabularies, and value sets **SHALL** be present and constrains how the elements are used. Providing the floor for standards development for specific use cases promotes interoperability and adoption.",
  "jurisdiction" : [{
    "coding" : [{
      "system" : "urn:iso:std:iso:3166",
      "code" : "US"
    }]
  }],
  "copyright" : "Used by permission of HL7 International, all rights reserved Creative Commons License",
  "fhirVersion" : "4.0.1",
  "mapping" : [{
    "identity" : "workflow",
    "uri" : "http://hl7.org/fhir/workflow",
    "name" : "Workflow Pattern"
  },
  {
    "identity" : "sct-concept",
    "uri" : "http://snomed.info/conceptdomain",
    "name" : "SNOMED CT Concept Domain Binding"
  },
  {
    "identity" : "v2",
    "uri" : "http://hl7.org/v2",
    "name" : "HL7 v2 Mapping"
  },
  {
    "identity" : "rim",
    "uri" : "http://hl7.org/v3",
    "name" : "RIM Mapping"
  },
  {
    "identity" : "w5",
    "uri" : "http://hl7.org/fhir/fivews",
    "name" : "FiveWs Pattern Mapping"
  },
  {
    "identity" : "sct-attr",
    "uri" : "http://snomed.org/attributebinding",
    "name" : "SNOMED CT Attribute Binding"
  }],
  "kind" : "resource",
  "abstract" : false,
  "type" : "Observation",
  "baseDefinition" : "http://hl7.org/fhir/StructureDefinition/Observation",
  "derivation" : "constraint",
  "differential" : {
    "element" : [{
      "id" : "Observation",
      "path" : "Observation",
      "short" : "assessment observation"
    },
    {
      "id" : "Observation.status",
      "path" : "Observation.status",
      "mustSupport" : true
    },
    {
      "id" : "Observation.category",
      "path" : "Observation.category",
      "slicing" : {
        "discriminator" : [{
          "type" : "value",
          "path" : "$this"
        }],
        "rules" : "open"
      },
      "min" : 1,
      "mustSupport" : true,
      "binding" : {
        "strength" : "preferred",
        "description" : "FHIR and US Core codes for high level observation categories.",
        "valueSet" : "http://hl7.org/fhir/us/core/ValueSet/us-core-simple-observation-category"
      }
    },
    {
      "id" : "Observation.category:us-core",
      "extension" : [{
        "url" : "http://hl7.org/fhir/us/core/StructureDefinition/uscdi-requirement",
        "valueBoolean" : true
      }],
      "path" : "Observation.category",
      "sliceName" : "us-core",
      "short" : "𝗔𝗗𝗗𝗜𝗧𝗜𝗢𝗡𝗔𝗟 𝗨𝗦𝗖𝗗𝗜: US Core classification of type of observation",
      "min" : 0,
      "mustSupport" : false,
      "binding" : {
        "extension" : [{
          "url" : "http://hl7.org/fhir/StructureDefinition/elementdefinition-minValueSet",
          "valueCanonical" : "http://hl7.org/fhir/us/core/ValueSet/us-core-screening-assessment-observation-category"
        }],
        "strength" : "required",
        "description" : "Note that other codes are permitted, see [Required Bindings When Slicing by Value Sets](general-requirements.html#required-bindings-when-slicing-by-valuesets)",
        "valueSet" : "http://hl7.org/fhir/us/core/ValueSet/us-core-simple-observation-category"
      }
    },
    {
      "id" : "Observation.code",
      "path" : "Observation.code",
      "mustSupport" : true,
      "binding" : {
        "strength" : "preferred"
      }
    },
    {
      "id" : "Observation.subject",
      "path" : "Observation.subject",
      "min" : 1,
      "type" : [{
        "code" : "Reference",
        "targetProfile" : ["http://hl7.org/fhir/us/core/StructureDefinition/us-core-patient",
        "http://hl7.org/fhir/StructureDefinition/Group",
        "http://hl7.org/fhir/StructureDefinition/Device",
        "http://hl7.org/fhir/us/core/StructureDefinition/us-core-location"],
        "_targetProfile" : [{
          "extension" : [{
            "url" : "http://hl7.org/fhir/StructureDefinition/elementdefinition-type-must-support",
            "valueBoolean" : true
          }]
        },
        {
          "extension" : [{
            "url" : "http://hl7.org/fhir/StructureDefinition/elementdefinition-type-must-support",
            "valueBoolean" : false
          }]
        },
        {
          "extension" : [{
            "url" : "http://hl7.org/fhir/StructureDefinition/elementdefinition-type-must-support",
            "valueBoolean" : false
          }]
        },
        {
          "extension" : [{
            "url" : "http://hl7.org/fhir/StructureDefinition/elementdefinition-type-must-support",
            "valueBoolean" : false
          }]
        }]
      }],
      "mustSupport" : true
    },
    {
      "id" : "Observation.effective[x]",
      "path" : "Observation.effective[x]",
      "definition" : "The time or time-period the observed value is asserted as being true. For biological subjects - e.g., human patients - this is usually called the \"physiologically relevant time\".",
      "comment" : "At least a date should be present unless this observation is a historical report.",
      "type" : [{
        "extension" : [{
          "url" : "http://hl7.org/fhir/StructureDefinition/elementdefinition-type-must-support",
          "valueBoolean" : true
        }],
        "code" : "dateTime"
      },
      {
        "code" : "Period"
      },
      {
        "code" : "Timing"
      },
      {
        "code" : "instant"
      }],
      "mustSupport" : true
    },
    {
      "id" : "Observation.performer",
      "path" : "Observation.performer",
      "type" : [{
        "code" : "Reference",
        "targetProfile" : ["http://hl7.org/fhir/us/core/StructureDefinition/us-core-practitioner",
        "http://hl7.org/fhir/us/core/StructureDefinition/us-core-patient",
        "http://hl7.org/fhir/us/core/StructureDefinition/us-core-organization",
        "http://hl7.org/fhir/StructureDefinition/PractitionerRole",
        "http://hl7.org/fhir/us/core/StructureDefinition/us-core-careteam",
        "http://hl7.org/fhir/us/core/StructureDefinition/us-core-relatedperson"],
        "_targetProfile" : [{
          "extension" : [{
            "url" : "http://hl7.org/fhir/StructureDefinition/elementdefinition-type-must-support",
            "valueBoolean" : true
          }]
        },
        {
          "extension" : [{
            "url" : "http://hl7.org/fhir/StructureDefinition/elementdefinition-type-must-support",
            "valueBoolean" : true
          }]
        },
        {
          "extension" : [{
            "url" : "http://hl7.org/fhir/StructureDefinition/elementdefinition-type-must-support",
            "valueBoolean" : false
          }]
        },
        {
          "extension" : [{
            "url" : "http://hl7.org/fhir/StructureDefinition/elementdefinition-type-must-support",
            "valueBoolean" : false
          }]
        },
        {
          "extension" : [{
            "url" : "http://hl7.org/fhir/StructureDefinition/elementdefinition-type-must-support",
            "valueBoolean" : false
          }]
        },
        {
          "extension" : [{
            "url" : "http://hl7.org/fhir/StructureDefinition/elementdefinition-type-must-support",
            "valueBoolean" : false
          }]
        }]
      }],
      "mustSupport" : true
    },
    {
      "id" : "Observation.value[x]",
      "path" : "Observation.value[x]",
      "type" : [{
        "extension" : [{
          "url" : "http://hl7.org/fhir/StructureDefinition/elementdefinition-type-must-support",
          "valueBoolean" : true
        }],
        "code" : "Quantity"
      },
      {
        "extension" : [{
          "url" : "http://hl7.org/fhir/StructureDefinition/elementdefinition-type-must-support",
          "valueBoolean" : true
        }],
        "code" : "CodeableConcept"
      },
      {
        "extension" : [{
          "url" : "http://hl7.org/fhir/StructureDefinition/elementdefinition-type-must-support",
          "valueBoolean" : true
        }],
        "code" : "string"
      },
      {
        "extension" : [{
          "url" : "http://hl7.org/fhir/StructureDefinition/elementdefinition-type-must-support",
          "valueBoolean" : true
        }],
        "code" : "boolean"
      },
      {
        "code" : "integer"
      },
      {
        "code" : "Range"
      },
      {
        "code" : "Ratio"
      },
      {
        "code" : "SampledData"
      },
      {
        "code" : "time"
      },
      {
        "code" : "dateTime"
      },
      {
        "code" : "Period"
      }],
      "mustSupport" : true
    },
    {
      "id" : "Observation.derivedFrom",
      "extension" : [{
        "url" : "http://hl7.org/fhir/us/core/StructureDefinition/uscdi-requirement",
        "valueBoolean" : true
      }],
      "path" : "Observation.derivedFrom",
      "short" : "𝗔𝗗𝗗𝗜𝗧𝗜𝗢𝗡𝗔𝗟 𝗨𝗦𝗖𝗗𝗜: US Core Profiles or other resource the observation is made from",
      "definition" : "US Core Observations, DocumentReference, QuestionnaireResponse or other resource from which this observation value is derived.",
      "type" : [{
        "code" : "Reference",
        "targetProfile" : ["http://hl7.org/fhir/StructureDefinition/Observation",
        "http://hl7.org/fhir/us/core/StructureDefinition/us-core-documentreference",
        "http://hl7.org/fhir/us/core/StructureDefinition/us-core-questionnaireresponse",
        "http://hl7.org/fhir/StructureDefinition/ImagingStudy",
        "http://hl7.org/fhir/StructureDefinition/Media",
        "http://hl7.org/fhir/StructureDefinition/MolecularSequence"],
        "_targetProfile" : [{
          "extension" : [{
            "url" : "http://hl7.org/fhir/StructureDefinition/elementdefinition-type-must-support",
            "valueBoolean" : false
          }]
        },
        {
          "extension" : [{
            "url" : "http://hl7.org/fhir/StructureDefinition/elementdefinition-type-must-support",
            "valueBoolean" : false
          }]
        },
        {
          "extension" : [{
            "url" : "http://hl7.org/fhir/StructureDefinition/elementdefinition-type-must-support",
            "valueBoolean" : false
          }]
        },
        {
          "extension" : [{
            "url" : "http://hl7.org/fhir/StructureDefinition/elementdefinition-type-must-support",
            "valueBoolean" : false
          }]
        },
        {
          "extension" : [{
            "url" : "http://hl7.org/fhir/StructureDefinition/elementdefinition-type-must-support",
            "valueBoolean" : false
          }]
        },
        {
          "extension" : [{
            "url" : "http://hl7.org/fhir/StructureDefinition/elementdefinition-type-must-support",
            "valueBoolean" : false
          }]
        }]
      }],
      "mustSupport" : false
    }]
  }
}

```
