US Core Implementation Guide
8.0.1 - STU 8 US

US Core Implementation Guide, published by HL7 International / Cross-Group Projects. This guide is not an authorized publication; it is the continuous build for version 8.0.1 built by the FHIR (HL7® FHIR® Standard) CI Build. This version is based on the current content of https://github.com/HL7/US-Core/ and changes regularly. See the Directory of published versions

## Resource Profile: US Core Laboratory Result Observation Profile

Official URL: http://hl7.org/fhir/us/core/StructureDefinition/us-core-observation-lab | Version: 8.0.1
Standards status: Trial-use | Maturity Level: 3 | Computable Name: USCoreLaboratoryResultObservationProfile
Other Identifiers: OID:2.16.840.1.113883.4.642.40.2.42.42
Copyright/Legal: Used by permission of HL7 International, all rights reserved Creative Commons License

The US Core Laboratory Result Observation Profile is based upon the US Core Observation Clinical Result Profile and, along with the US Core DiagnosticReport Profile for Laboratory Results Reporting, meets the U.S. Core Data for Interoperability (USCDI) Laboratory requirements. Laboratory results are grouped and summarized using the DiagnosticReport resource, which references Observation resources. Each Observation resource represents an individual laboratory test and result value, a “nested” panel (such as a microbial susceptibility panel) that references other observations, or rarely a laboratory test with component result values. The US Core Laboratory Result Observation Profile sets minimum expectations for the Observation resource to record, search, and fetch laboratory test results associated with a patient to promote interoperability and adoption through common implementation. It identifies which core elements, extensions, vocabularies, and value sets SHALL be present in the resource and constrains the way the elements are used when using this profile. It provides the floor for standards development for specific use cases.

Example Usage Scenarios:

The following are example usage scenarios for this profile:

- Query for lab results belonging to a Patient
- Record or update lab results belonging to a Patient

### Mandatory and Must Support Data Elements

In addition to the Mandatory and Must Support data elements in the US Core Observation Clinical Result Profile, the following data elements must always be present (Mandatory definition) or must be supported if the data is present in the sending system (Must Support definition). They are presented below in a simple human-readable explanation. Profile specific guidance and examples are provided as well. The Formal Views section below provides the formal summary, definitions, and terminology requirements. Note that the "Differential Table" displays elements unique to this profile and the "Key Elements Table” displays a combined view of elements for this profile and the US Core Observation Clinical Result Profile.

Each Observation Must Have:

1. a category code of 'laboratory'
2. a laboratory LOINC code, if available, which tells you what is being measured

Each Observation Must Support:

1. a timestamp when the resource last changed*
2. a result value*
   - if the result value is a numeric quantity, a standard UCUM unit
   - if the result value is a coded quantity, a standard SNOMED CT
3. result interpretation
   - if the result value is a numeric quantity, a standard UCUM unit
4. result reference range
5. a specimen type (e.g., blood, serum, urine)*

Additional USCDI Requirements:

This 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 ServiceRequest examples.

1. the name of the test that was performed

* see guidance below

Profile Specific Implementation Guidance:

- For USCDI, systems are required to use SNOMED CT for coded results if the SCT code exists.
- The CLIA/USCDI/HL7 Elements Crossmapping Table provides a crosswalk of Clinical Laboratory Improvement Amendments (CLIA) data elements to corresponding FHIR fields, terminology standards, and naming conventions used in HL7 CDA and HL7 V2 standards. Implementers can use this mapping to help comply with CLIA requirements when using the US Core Laboratory Result Observation Profile.

- The `Observation.category` element provides an efficient way of restricting search on observations to a given context such as laboratory observations. Example searches are shown in the Quick Start section below. However, Clients need to understand that data categorization is somewhat subjective. The categorization applied by the source may not align with the Client's expectations. Clients may find it more useful to use queries based on a specific code or set of codes or to perform additional Client-side filtering of query results.
- Additional codes that translate or map to the Observation code or category codes are allowed. For example:
  - providing both a local code and a LOINC code
  - providing a more specific code such as 'chemistry', a SNOMED CT concept, or a system-specific code
- Systems SHOULD support `Observation.effectivePeriod` to accurately represent measurements over time (for example, a 24-Hour Urine Collection test).
- *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 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 General Guidance page for further guidance on SNOMED and UCUM.
- See the LOINC scale type to FHIR data type mapping for guidance on which `Observation.value[x]` data type to use based on the LOINC Type of Scale.

- *This profile inherits the invariant "us-core-3" from the US Core Observation Clinical Result Profile that requires UCUM to be used as a unit type for `Observation.valueQuantity.code`.
- *Even when the specimen type is already implied by the LOINC code used in `Observation.code` (e.g., a LOINC code for Blood Glucose), the `Observation.specimen` element SHOULD also be populated with the referenced Specimen resource to explicitly communicate the collected specimen type. The type of specimen SHOULD not conflict with the LOINC code.
- * See the US Core General Guidance page for Searching Using lastUpdated. Updates to `.meta.lastUpdated` SHOULD reflect:
  - New laboratory observations
  - Changes in the status of laboratory observations, including events that trigger the same status (e.g., amended → amended).

Usages:

- Refer to this Profile: US Core DiagnosticReport Profile for Laboratory Results Reporting and US Core DiagnosticReport Profile for Report and Note Exchange
- Examples for this Profile: Observation/at-home-in-vitro-test, Observation/cbc-erythrocytes, Observation/cbc-hematocrit, Observation/cbc-hemoglobin... Show 14 more, Observation/cbc-leukocytes, Observation/cbc-mch, Observation/cbc-mchc, Observation/cbc-mcv, Observation/cbc-platelets, Observation/serum-bun, Observation/serum-calcium, Observation/serum-chloride, Observation/serum-co2, Observation/serum-creatinine, Observation/serum-glucose, Observation/serum-potassium, Observation/serum-sodium and Observation/urobilinogen
- CapabilityStatements using this Profile: US Core Client CapabilityStatement and US Core Server CapabilityStatement

You can also check for usages in the FHIR IG Statistics

Changes since version 7.0.0:

- New Content

### Formal Views of Profile Content

Description of Profiles, Differentials, Snapshots and how the different presentations work.

- Key Elements Table
- Differential Table
- Snapshot Table
- Statistics/References
- All

Name | Flags | Card. | Type | Description & Constraints Filter: Bindings Constraints Obligations
--- | --- | --- | --- | ---
Observation | C | 0..* | USCoreObservationClinicalResultProfile | Measurements and simple assertions Constraints: obs-6, obs-7, us-core-2
meta | S Σ | 0..1 | Meta | Metadata about the resource
lastUpdated | S Σ | 0..1 | instant | When the resource last changed
implicitRules | ?!Σ | 0..1 | uri | A set of rules under which this content was created
modifierExtension | ?! | 0..* | Extension | Extensions that cannot be ignored
status | ?!S Σ | 1..1 | code | registered | preliminary | final | amended + Binding: ObservationStatus (required): Codes providing the status of an observation.
Slices for category | S | 1..* | CodeableConcept | Classification of type of observation Slice: Unordered, Open by value:$this Binding: ObservationCategoryCodes (preferred): Codes for high level observation categories.
category:us-core | S | 1..1 | CodeableConcept | Classification of type of observation Binding: US Core Clinical Result Observation Category (required): Note that other codes are permitted, see Required Bindings When Slicing by Value Sets Required Pattern: At least the following
id |  | 0..1 | string | Unique id for inter-element referencing
extension |  | 0..* | Extension | Additional content defined by implementations
coding |  | 1..* | Coding | Code defined by a terminology system Fixed Value: (Complex)
id |  | 0..1 | string | Unique id for inter-element referencing
extension |  | 0..* | Extension | Additional content defined by implementations
system |  | 1..1 | uri | Identity of the terminology system Fixed Value: http://terminology.hl7.org/CodeSystem/observation-category
version |  | 0..1 | string | Version of the system - if relevant
code |  | 1..1 | code | Symbol in syntax defined by the system Fixed Value: laboratory
display |  | 0..1 | string | Representation defined by the system
userSelected |  | 0..1 | boolean | If this coding was chosen directly by the user
text |  | 0..1 | string | Plain text representation of the concept
code | S Σ | 1..1 | CodeableConcept | Laboratory Test Name Binding: US Core Laboratory Test Codes (extensible): Laboratory LOINC Codes
text | Σ | 0..1 | string | 𝗔𝗗𝗗𝗜𝗧𝗜𝗢𝗡𝗔𝗟 𝗨𝗦𝗖𝗗𝗜: The name of the test that was performed.
subject | S Σ | 1..1 | Reference(US Core Patient Profile S | Group | Device | US Core Location Profile) | Who and/or what the observation is about
encounter | S Σ | 0..1 | Reference(US Core Encounter Profile) | Encounter associated with Observation
effective[x] | S Σ C | 0..1 |  | Clinically relevant time/time-period for observation Constraints: us-core-1
effectiveDateTime |  |  | dateTime S |
effectivePeriod |  |  | Period |
effectiveTiming |  |  | Timing |
effectiveInstant |  |  | instant |
performer | S Σ | 0..* | Reference(US Core Practitioner Profile S | US Core Organization Profile | US Core Patient Profile | PractitionerRole | US Core CareTeam Profile | US Core RelatedPerson Profile) | Who is responsible for the observation
value[x] | S Σ C | 0..1 |  | Result Value Constraints: us-core-3, us-core-4
valueQuantity |  |  | Quantity S |
valueCodeableConcept |  |  | CodeableConcept S |
valueString |  |  | string S |
valueBoolean |  |  | boolean |
valueInteger |  |  | integer |
valueRange |  |  | Range |
valueRatio |  |  | Ratio |
valueSampledData |  |  | SampledData |
valueTime |  |  | time |
valueDateTime |  |  | dateTime |
valuePeriod |  |  | Period |
dataAbsentReason | S C | 0..1 | CodeableConcept | Why the result is missing Binding: DataAbsentReason (extensible): Codes specifying why the result (Observation.value[x]) is missing.
interpretation | S | 0..* | CodeableConcept | Result interpretation Binding: ObservationInterpretationCodes (extensible): Observation Interpretation Codes
specimen | S | 0..1 | Reference(US Core Specimen Profile) | Specimen used for this observation
referenceRange | S C | 0..* | BackboneElement | Result reference range Constraints: obs-3, us-core-22
modifierExtension | ?!Σ | 0..* | Extension | Extensions that cannot be ignored even if unrecognized
Documentation for this format

#### Terminology Bindings

Path | Status | Usage | ValueSet | Version | Source
Observation.status | Base | required | ObservationStatus | 📍4.0.1 | FHIR Std.
Observation.category | Base | preferred | Observation Category Codes | 📍4.0.1 | FHIR Std.
Observation.category:us-core | Base | required | US Core Clinical Result Observation Category | 📦8.0.1 | This IG
Observation.code | Base | extensible | US Core Laboratory Test Codes | 📦8.0.1 | This IG
Observation.dataAbsentReason | Base | extensible | DataAbsentReason | 📍4.0.1 | FHIR Std.
Observation.interpretation | Base | extensible | Observation Interpretation Codes | 📦4.0.1 | FHIR Std.

#### Constraints

Id | Grade | Path(s) | Description | Expression
dom-2 | error | Observation | If the resource is contained in another resource, it SHALL NOT contain nested Resources | `contained.contained.empty()`
dom-3 | error | Observation | If the resource is contained in another resource, it SHALL be referred to from elsewhere in the resource or SHALL refer to the containing resource | `contained.where((('#'+id in (%resource.descendants().reference | %resource.descendants().as(canonical) | %resource.descendants().as(uri) | %resource.descendants().as(url))) or descendants().where(reference = '#').exists() or descendants().where(as(canonical) = '#').exists() or descendants().where(as(canonical) = '#').exists()).not()).trace('unmatched', id).empty()`
dom-4 | error | Observation | If a resource is contained in another resource, it SHALL NOT have a meta.versionId or a meta.lastUpdated | `contained.meta.versionId.empty() and contained.meta.lastUpdated.empty()`
dom-5 | error | Observation | If a resource is contained in another resource, it SHALL NOT have a security label | `contained.meta.security.empty()`
dom-6 | best practice | Observation | A resource should have narrative for robust management | `text.`div`.exists()`
ele-1 | error | **ALL** elements | All FHIR elements must have a @value or children | `hasValue() or (children().count() > id.count())`
ext-1 | error | **ALL** extensions | Must have either extensions or value[x], not both | `extension.exists() != value.exists()`
obs-3 | error | Observation.referenceRange | Must have at least a low or a high or text | `low.exists() or high.exists() or text.exists()`
obs-6 | error | Observation | dataAbsentReason SHALL only be present if Observation.value[x] is not present | `dataAbsentReason.empty() or value.empty()`
obs-7 | error | Observation | If Observation.code is the same as an Observation.component.code then the value element associated with the code SHALL NOT be present | `value.empty() or component.code.where(coding.intersect(%resource.code.coding).exists()).empty()`
us-core-1 | error | Observation.effective[x] | Datetime must be at least to day. | `$this is dateTime implies $this.toString().length() >= 10`
us-core-2 | error | Observation | If there is no component or hasMember element then either a value[x] or a data absent reason must be present | `(component.empty() and hasMember.empty()) implies (dataAbsentReason.exists() or value.exists())`
us-core-3 | error | Observation.value[x] | SHALL use UCUM for coded quantity units. | `ofType(Quantity).system.empty() or ofType(Quantity).system = 'http://unitsofmeasure.org'`
us-core-4 | best practice | Observation.value[x] | SHOULD use Snomed CT for coded Results | `ofType(CodeableConcept).coding.system.empty() or (ofType(CodeableConcept).coding.system contains 'http://snomed.info/sct')`
us-core-22 | error | Observation.referenceRange | SHALL use UCUM for coded quantity units. | `(low.system.empty() or low.system = 'http://unitsofmeasure.org') and (high.system.empty() or high.system = 'http://unitsofmeasure.org')`

This structure is derived from USCoreObservationClinicalResultProfile

Name | Flags | Card. | Type | Description & Constraints Filter: Bindings Constraints Obligations
--- | --- | --- | --- | ---
Observation |  | 0..* | USCoreObservationClinicalResultProfile | Measurements and simple assertions
meta | S | 0..1 | Meta | Metadata about the resource
lastUpdated | S | 0..1 | instant | When the resource last changed
Slices for category |  |  |  | Content/Rules for all slices
category:us-core | S | 1..1 | CodeableConcept | Classification of type of observation Required Pattern: At least the following
coding |  | 1..* | Coding | Code defined by a terminology system Fixed Value: (Complex)
system |  | 1..1 | uri | Identity of the terminology system Fixed Value: http://terminology.hl7.org/CodeSystem/observation-category
code |  | 1..1 | code | Symbol in syntax defined by the system Fixed Value: laboratory
code | S | 1..1 | CodeableConcept | Laboratory Test Name Binding: US Core Laboratory Test Codes (extensible): Laboratory LOINC Codes
text |  | 0..1 | string | 𝗔𝗗𝗗𝗜𝗧𝗜𝗢𝗡𝗔𝗟 𝗨𝗦𝗖𝗗𝗜: The name of the test that was performed.
value[x] | S C | 0..1 |  | Result Value Constraints: us-core-4
valueQuantity |  |  | Quantity S |
valueCodeableConcept |  |  | CodeableConcept S |
valueString |  |  | string S |
valueBoolean |  |  | boolean |
valueInteger |  |  | integer |
valueRange |  |  | Range |
valueRatio |  |  | Ratio |
valueSampledData |  |  | SampledData |
valueTime |  |  | time |
valueDateTime |  |  | dateTime |
valuePeriod |  |  | Period |
interpretation | S | 0..* | CodeableConcept | Result interpretation Binding: ObservationInterpretationCodes (extensible): Observation Interpretation Codes
specimen | S | 0..1 | Reference(US Core Specimen Profile) | Specimen used for this observation
referenceRange | S C | 0..* | BackboneElement | Result reference range Constraints: us-core-22
Documentation for this format

#### Terminology Bindings (Differential)

Path | Status | Usage | ValueSet | Version | Source
Observation.code | Base | extensible | US Core Laboratory Test Codes | 📦8.0.1 | This IG
Observation.interpretation | Base | extensible | Observation Interpretation Codes | 📦4.0.1 | FHIR Std.

#### Constraints

Id | Grade | Path(s) | Description | Expression
us-core-4 | best practice | Observation.value[x] | SHOULD use Snomed CT for coded Results | `ofType(CodeableConcept).coding.system.empty() or (ofType(CodeableConcept).coding.system contains 'http://snomed.info/sct')`
us-core-22 | error | Observation.referenceRange | SHALL use UCUM for coded quantity units. | `(low.system.empty() or low.system = 'http://unitsofmeasure.org') and (high.system.empty() or high.system = 'http://unitsofmeasure.org')`

Name | Flags | Card. | Type | Description & Constraints Filter: Bindings Constraints Obligations
--- | --- | --- | --- | ---
Observation | C | 0..* | USCoreObservationClinicalResultProfile | Measurements and simple assertions Constraints: obs-6, obs-7, us-core-2
id | Σ | 0..1 | id | Logical id of this artifact
meta | S Σ | 0..1 | Meta | Metadata about the resource
id |  | 0..1 | string | Unique id for inter-element referencing
extension |  | 0..* | Extension | Additional content defined by implementations Slice: Unordered, Open by value:url
versionId | Σ | 0..1 | id | Version specific identifier
lastUpdated | S Σ | 0..1 | instant | When the resource last changed
source | Σ | 0..1 | uri | Identifies where the resource comes from
profile | Σ | 0..* | canonical(StructureDefinition) | Profiles this resource claims to conform to
security | Σ | 0..* | Coding | Security Labels applied to this resource Binding: All Security Labels (extensible): Security Labels from the Healthcare Privacy and Security Classification System.
tag | Σ | 0..* | Coding | Tags applied to this resource Binding: CommonTags (example): Codes that represent various types of tags, commonly workflow-related; e.g. "Needs review by Dr. Jones".
implicitRules | ?!Σ | 0..1 | uri | A set of rules under which this content was created
language |  | 0..1 | code | Language of the resource content Binding: CommonLanguages (preferred): A human language.
Additional Bindings | Purpose
AllLanguages | Max Binding
text |  | 0..1 | Narrative | Text summary of the resource, for human interpretation This profile does not constrain the narrative in regard to content, language, or traceability to data elements
contained |  | 0..* | Resource | Contained, inline Resources
extension |  | 0..* | Extension | Additional content defined by implementations
modifierExtension | ?! | 0..* | Extension | Extensions that cannot be ignored
identifier | Σ | 0..* | Identifier | Business Identifier for observation
basedOn | Σ | 0..* | Reference(CarePlan | DeviceRequest | ImmunizationRecommendation | MedicationRequest | NutritionOrder | ServiceRequest) | Fulfills plan, proposal or order
partOf | Σ | 0..* | Reference(MedicationAdministration | MedicationDispense | MedicationStatement | Procedure | Immunization | ImagingStudy) | Part of referenced event
status | ?!S Σ | 1..1 | code | registered | preliminary | final | amended + Binding: ObservationStatus (required): Codes providing the status of an observation.
Slices for category | S | 1..* | CodeableConcept | Classification of type of observation Slice: Unordered, Open by value:$this Binding: ObservationCategoryCodes (preferred): Codes for high level observation categories.
category:us-core | S | 1..1 | CodeableConcept | Classification of type of observation Binding: US Core Clinical Result Observation Category (required): Note that other codes are permitted, see Required Bindings When Slicing by Value Sets Required Pattern: At least the following
id |  | 0..1 | string | Unique id for inter-element referencing
extension |  | 0..* | Extension | Additional content defined by implementations
coding |  | 1..* | Coding | Code defined by a terminology system Fixed Value: (Complex)
id |  | 0..1 | string | Unique id for inter-element referencing
extension |  | 0..* | Extension | Additional content defined by implementations
system |  | 1..1 | uri | Identity of the terminology system Fixed Value: http://terminology.hl7.org/CodeSystem/observation-category
version |  | 0..1 | string | Version of the system - if relevant
code |  | 1..1 | code | Symbol in syntax defined by the system Fixed Value: laboratory
display |  | 0..1 | string | Representation defined by the system
userSelected |  | 0..1 | boolean | If this coding was chosen directly by the user
text |  | 0..1 | string | Plain text representation of the concept
code | S Σ | 1..1 | CodeableConcept | Laboratory Test Name Binding: US Core Laboratory Test Codes (extensible): Laboratory LOINC Codes
id |  | 0..1 | string | Unique id for inter-element referencing
extension |  | 0..* | Extension | Additional content defined by implementations Slice: Unordered, Open by value:url
coding | Σ | 0..* | Coding | Code defined by a terminology system
text | Σ | 0..1 | string | 𝗔𝗗𝗗𝗜𝗧𝗜𝗢𝗡𝗔𝗟 𝗨𝗦𝗖𝗗𝗜: The name of the test that was performed.
subject | S Σ | 1..1 | Reference(US Core Patient Profile S | Group | Device | US Core Location Profile) | Who and/or what the observation is about
focus | Σ | 0..* | Reference(Resource) | What the observation is about, when it is not about the subject of record
encounter | S Σ | 0..1 | Reference(US Core Encounter Profile) | Encounter associated with Observation
effective[x] | S Σ C | 0..1 |  | Clinically relevant time/time-period for observation Constraints: us-core-1
effectiveDateTime |  |  | dateTime S |
effectivePeriod |  |  | Period |
effectiveTiming |  |  | Timing |
effectiveInstant |  |  | instant |
issued | Σ | 0..1 | instant | Date/Time this version was made available
performer | S Σ | 0..* | Reference(US Core Practitioner Profile S | US Core Organization Profile | US Core Patient Profile | PractitionerRole | US Core CareTeam Profile | US Core RelatedPerson Profile) | Who is responsible for the observation
value[x] | S Σ C | 0..1 |  | Result Value Constraints: us-core-3, us-core-4
valueQuantity |  |  | Quantity S |
valueCodeableConcept |  |  | CodeableConcept S |
valueString |  |  | string S |
valueBoolean |  |  | boolean |
valueInteger |  |  | integer |
valueRange |  |  | Range |
valueRatio |  |  | Ratio |
valueSampledData |  |  | SampledData |
valueTime |  |  | time |
valueDateTime |  |  | dateTime |
valuePeriod |  |  | Period |
dataAbsentReason | S C | 0..1 | CodeableConcept | Why the result is missing Binding: DataAbsentReason (extensible): Codes specifying why the result (Observation.value[x]) is missing.
interpretation | S | 0..* | CodeableConcept | Result interpretation Binding: ObservationInterpretationCodes (extensible): Observation Interpretation Codes
note |  | 0..* | Annotation | Comments about the observation
bodySite |  | 0..1 | CodeableConcept | Observed body part Binding: SNOMEDCTBodyStructures (example): Codes describing anatomical locations. May include laterality.
method |  | 0..1 | CodeableConcept | How it was done Binding: ObservationMethods (example): Methods for simple observations.
specimen | S | 0..1 | Reference(US Core Specimen Profile) | Specimen used for this observation
device |  | 0..1 | Reference(Device | DeviceMetric) | (Measurement) Device
referenceRange | S C | 0..* | BackboneElement | Result reference range Constraints: obs-3, us-core-22
id |  | 0..1 | string | Unique id for inter-element referencing
extension |  | 0..* | Extension | Additional content defined by implementations
modifierExtension | ?!Σ | 0..* | Extension | Extensions that cannot be ignored even if unrecognized
low | C | 0..1 | SimpleQuantity(4.0.1) | Low Range, if relevant
high | C | 0..1 | SimpleQuantity(4.0.1) | High Range, if relevant
type |  | 0..1 | CodeableConcept | Reference range qualifier Binding: ObservationReferenceRangeMeaningCodes (preferred): Code for the meaning of a reference range.
appliesTo |  | 0..* | CodeableConcept | Reference range population Binding: ObservationReferenceRangeAppliesToCodes (example): Codes identifying the population the reference range applies to.
age |  | 0..1 | Range | Applicable age range, if relevant
text |  | 0..1 | string | Text based reference range in an observation
hasMember | Σ | 0..* | Reference(Observation | QuestionnaireResponse | MolecularSequence) | Related resource that belongs to the Observation group
derivedFrom | Σ | 0..* | Reference(DocumentReference | ImagingStudy | Media | QuestionnaireResponse | Observation | MolecularSequence) | Related measurements the observation is made from
component | Σ | 0..* | BackboneElement | Component results
id |  | 0..1 | string | Unique id for inter-element referencing
extension |  | 0..* | Extension | Additional content defined by implementations
modifierExtension | ?!Σ | 0..* | Extension | Extensions that cannot be ignored even if unrecognized
code | Σ | 1..1 | CodeableConcept | Type of component observation (code / type) Binding: LOINCCodes (example): Codes identifying names of simple observations.
value[x] | Σ | 0..1 |  | Actual component result
valueQuantity |  |  | Quantity |
valueCodeableConcept |  |  | CodeableConcept |
valueString |  |  | string |
valueBoolean |  |  | boolean |
valueInteger |  |  | integer |
valueRange |  |  | Range |
valueRatio |  |  | Ratio |
valueSampledData |  |  | SampledData |
valueTime |  |  | time |
valueDateTime |  |  | dateTime |
valuePeriod |  |  | Period |
dataAbsentReason | C | 0..1 | CodeableConcept | Why the component result is missing Binding: DataAbsentReason (extensible): Codes specifying why the result (Observation.value[x]) is missing.
interpretation |  | 0..* | CodeableConcept | High, low, normal, etc. Binding: ObservationInterpretationCodes (extensible): Codes identifying interpretations of observations.
referenceRange |  | 0..* | See referenceRange (Observation) | Provides guide for interpretation of component result
Documentation for this format

#### Terminology Bindings

Path | Status | Usage | ValueSet | Version | Source
Observation.meta.security | Base | extensible | SecurityLabels | 📍4.0.1 | FHIR Std.
Observation.meta.tag | Base | example | Common Tags | 📍4.0.1 | FHIR Std.
Observation.language | Base | preferred | Common Languages | 📍4.0.1 | FHIR Std.
Observation.status | Base | required | ObservationStatus | 📍4.0.1 | FHIR Std.
Observation.category | Base | preferred | Observation Category Codes | 📍4.0.1 | FHIR Std.
Observation.category:us-core | Base | required | US Core Clinical Result Observation Category | 📦8.0.1 | This IG
Observation.code | Base | extensible | US Core Laboratory Test Codes | 📦8.0.1 | This IG
Observation.dataAbsentReason | Base | extensible | DataAbsentReason | 📍4.0.1 | FHIR Std.
Observation.interpretation | Base | extensible | Observation Interpretation Codes | 📦4.0.1 | FHIR Std.
Observation.bodySite | Base | example | SNOMED CT Body Structures | 📍4.0.1 | FHIR Std.
Observation.method | Base | example | Observation Methods | 📍4.0.1 | FHIR Std.
Observation.referenceRange.​type | Base | preferred | Observation Reference Range Meaning Codes | 📍4.0.1 | FHIR Std.
Observation.referenceRange.​appliesTo | Base | example | Observation Reference Range Applies To Codes | 📍4.0.1 | FHIR Std.
Observation.component.​code | Base | example | LOINC Codes | 📍4.0.1 | FHIR Std.
Observation.component.​dataAbsentReason | Base | extensible | DataAbsentReason | 📍4.0.1 | FHIR Std.
Observation.component.​interpretation | Base | extensible | Observation Interpretation Codes | 📍4.0.1 | FHIR Std.

#### Constraints

Id | Grade | Path(s) | Description | Expression
dom-2 | error | Observation | If the resource is contained in another resource, it SHALL NOT contain nested Resources | `contained.contained.empty()`
dom-3 | error | Observation | If the resource is contained in another resource, it SHALL be referred to from elsewhere in the resource or SHALL refer to the containing resource | `contained.where((('#'+id in (%resource.descendants().reference | %resource.descendants().as(canonical) | %resource.descendants().as(uri) | %resource.descendants().as(url))) or descendants().where(reference = '#').exists() or descendants().where(as(canonical) = '#').exists() or descendants().where(as(canonical) = '#').exists()).not()).trace('unmatched', id).empty()`
dom-4 | error | Observation | If a resource is contained in another resource, it SHALL NOT have a meta.versionId or a meta.lastUpdated | `contained.meta.versionId.empty() and contained.meta.lastUpdated.empty()`
dom-5 | error | Observation | If a resource is contained in another resource, it SHALL NOT have a security label | `contained.meta.security.empty()`
dom-6 | best practice | Observation | A resource should have narrative for robust management | `text.`div`.exists()`
ele-1 | error | **ALL** elements | All FHIR elements must have a @value or children | `hasValue() or (children().count() > id.count())`
ext-1 | error | **ALL** extensions | Must have either extensions or value[x], not both | `extension.exists() != value.exists()`
obs-3 | error | Observation.referenceRange | Must have at least a low or a high or text | `low.exists() or high.exists() or text.exists()`
obs-6 | error | Observation | dataAbsentReason SHALL only be present if Observation.value[x] is not present | `dataAbsentReason.empty() or value.empty()`
obs-7 | error | Observation | If Observation.code is the same as an Observation.component.code then the value element associated with the code SHALL NOT be present | `value.empty() or component.code.where(coding.intersect(%resource.code.coding).exists()).empty()`
us-core-1 | error | Observation.effective[x] | Datetime must be at least to day. | `$this is dateTime implies $this.toString().length() >= 10`
us-core-2 | error | Observation | If there is no component or hasMember element then either a value[x] or a data absent reason must be present | `(component.empty() and hasMember.empty()) implies (dataAbsentReason.exists() or value.exists())`
us-core-3 | error | Observation.value[x] | SHALL use UCUM for coded quantity units. | `ofType(Quantity).system.empty() or ofType(Quantity).system = 'http://unitsofmeasure.org'`
us-core-4 | best practice | Observation.value[x] | SHOULD use Snomed CT for coded Results | `ofType(CodeableConcept).coding.system.empty() or (ofType(CodeableConcept).coding.system contains 'http://snomed.info/sct')`
us-core-22 | error | Observation.referenceRange | SHALL use UCUM for coded quantity units. | `(low.system.empty() or low.system = 'http://unitsofmeasure.org') and (high.system.empty() or high.system = 'http://unitsofmeasure.org')`

This structure is derived from USCoreObservationClinicalResultProfile

Summary

Mandatory: 1 element
Must-Support: 8 elements

Structures

This structure refers to these other structures:

- US Core Specimen Profile (http://hl7.org/fhir/us/core/StructureDefinition/us-core-specimen)

Maturity: 3

Key Elements View

Name | Flags | Card. | Type | Description & Constraints Filter: Bindings Constraints Obligations
--- | --- | --- | --- | ---
Observation | C | 0..* | USCoreObservationClinicalResultProfile | Measurements and simple assertions Constraints: obs-6, obs-7, us-core-2
meta | S Σ | 0..1 | Meta | Metadata about the resource
lastUpdated | S Σ | 0..1 | instant | When the resource last changed
implicitRules | ?!Σ | 0..1 | uri | A set of rules under which this content was created
modifierExtension | ?! | 0..* | Extension | Extensions that cannot be ignored
status | ?!S Σ | 1..1 | code | registered | preliminary | final | amended + Binding: ObservationStatus (required): Codes providing the status of an observation.
Slices for category | S | 1..* | CodeableConcept | Classification of type of observation Slice: Unordered, Open by value:$this Binding: ObservationCategoryCodes (preferred): Codes for high level observation categories.
category:us-core | S | 1..1 | CodeableConcept | Classification of type of observation Binding: US Core Clinical Result Observation Category (required): Note that other codes are permitted, see Required Bindings When Slicing by Value Sets Required Pattern: At least the following
id |  | 0..1 | string | Unique id for inter-element referencing
extension |  | 0..* | Extension | Additional content defined by implementations
coding |  | 1..* | Coding | Code defined by a terminology system Fixed Value: (Complex)
id |  | 0..1 | string | Unique id for inter-element referencing
extension |  | 0..* | Extension | Additional content defined by implementations
system |  | 1..1 | uri | Identity of the terminology system Fixed Value: http://terminology.hl7.org/CodeSystem/observation-category
version |  | 0..1 | string | Version of the system - if relevant
code |  | 1..1 | code | Symbol in syntax defined by the system Fixed Value: laboratory
display |  | 0..1 | string | Representation defined by the system
userSelected |  | 0..1 | boolean | If this coding was chosen directly by the user
text |  | 0..1 | string | Plain text representation of the concept
code | S Σ | 1..1 | CodeableConcept | Laboratory Test Name Binding: US Core Laboratory Test Codes (extensible): Laboratory LOINC Codes
text | Σ | 0..1 | string | 𝗔𝗗𝗗𝗜𝗧𝗜𝗢𝗡𝗔𝗟 𝗨𝗦𝗖𝗗𝗜: The name of the test that was performed.
subject | S Σ | 1..1 | Reference(US Core Patient Profile S | Group | Device | US Core Location Profile) | Who and/or what the observation is about
encounter | S Σ | 0..1 | Reference(US Core Encounter Profile) | Encounter associated with Observation
effective[x] | S Σ C | 0..1 |  | Clinically relevant time/time-period for observation Constraints: us-core-1
effectiveDateTime |  |  | dateTime S |
effectivePeriod |  |  | Period |
effectiveTiming |  |  | Timing |
effectiveInstant |  |  | instant |
performer | S Σ | 0..* | Reference(US Core Practitioner Profile S | US Core Organization Profile | US Core Patient Profile | PractitionerRole | US Core CareTeam Profile | US Core RelatedPerson Profile) | Who is responsible for the observation
value[x] | S Σ C | 0..1 |  | Result Value Constraints: us-core-3, us-core-4
valueQuantity |  |  | Quantity S |
valueCodeableConcept |  |  | CodeableConcept S |
valueString |  |  | string S |
valueBoolean |  |  | boolean |
valueInteger |  |  | integer |
valueRange |  |  | Range |
valueRatio |  |  | Ratio |
valueSampledData |  |  | SampledData |
valueTime |  |  | time |
valueDateTime |  |  | dateTime |
valuePeriod |  |  | Period |
dataAbsentReason | S C | 0..1 | CodeableConcept | Why the result is missing Binding: DataAbsentReason (extensible): Codes specifying why the result (Observation.value[x]) is missing.
interpretation | S | 0..* | CodeableConcept | Result interpretation Binding: ObservationInterpretationCodes (extensible): Observation Interpretation Codes
specimen | S | 0..1 | Reference(US Core Specimen Profile) | Specimen used for this observation
referenceRange | S C | 0..* | BackboneElement | Result reference range Constraints: obs-3, us-core-22
modifierExtension | ?!Σ | 0..* | Extension | Extensions that cannot be ignored even if unrecognized
Documentation for this format

#### Terminology Bindings

Path | Status | Usage | ValueSet | Version | Source
Observation.status | Base | required | ObservationStatus | 📍4.0.1 | FHIR Std.
Observation.category | Base | preferred | Observation Category Codes | 📍4.0.1 | FHIR Std.
Observation.category:us-core | Base | required | US Core Clinical Result Observation Category | 📦8.0.1 | This IG
Observation.code | Base | extensible | US Core Laboratory Test Codes | 📦8.0.1 | This IG
Observation.dataAbsentReason | Base | extensible | DataAbsentReason | 📍4.0.1 | FHIR Std.
Observation.interpretation | Base | extensible | Observation Interpretation Codes | 📦4.0.1 | FHIR Std.

#### Constraints

Id | Grade | Path(s) | Description | Expression
dom-2 | error | Observation | If the resource is contained in another resource, it SHALL NOT contain nested Resources | `contained.contained.empty()`
dom-3 | error | Observation | If the resource is contained in another resource, it SHALL be referred to from elsewhere in the resource or SHALL refer to the containing resource | `contained.where((('#'+id in (%resource.descendants().reference | %resource.descendants().as(canonical) | %resource.descendants().as(uri) | %resource.descendants().as(url))) or descendants().where(reference = '#').exists() or descendants().where(as(canonical) = '#').exists() or descendants().where(as(canonical) = '#').exists()).not()).trace('unmatched', id).empty()`
dom-4 | error | Observation | If a resource is contained in another resource, it SHALL NOT have a meta.versionId or a meta.lastUpdated | `contained.meta.versionId.empty() and contained.meta.lastUpdated.empty()`
dom-5 | error | Observation | If a resource is contained in another resource, it SHALL NOT have a security label | `contained.meta.security.empty()`
dom-6 | best practice | Observation | A resource should have narrative for robust management | `text.`div`.exists()`
ele-1 | error | **ALL** elements | All FHIR elements must have a @value or children | `hasValue() or (children().count() > id.count())`
ext-1 | error | **ALL** extensions | Must have either extensions or value[x], not both | `extension.exists() != value.exists()`
obs-3 | error | Observation.referenceRange | Must have at least a low or a high or text | `low.exists() or high.exists() or text.exists()`
obs-6 | error | Observation | dataAbsentReason SHALL only be present if Observation.value[x] is not present | `dataAbsentReason.empty() or value.empty()`
obs-7 | error | Observation | If Observation.code is the same as an Observation.component.code then the value element associated with the code SHALL NOT be present | `value.empty() or component.code.where(coding.intersect(%resource.code.coding).exists()).empty()`
us-core-1 | error | Observation.effective[x] | Datetime must be at least to day. | `$this is dateTime implies $this.toString().length() >= 10`
us-core-2 | error | Observation | If there is no component or hasMember element then either a value[x] or a data absent reason must be present | `(component.empty() and hasMember.empty()) implies (dataAbsentReason.exists() or value.exists())`
us-core-3 | error | Observation.value[x] | SHALL use UCUM for coded quantity units. | `ofType(Quantity).system.empty() or ofType(Quantity).system = 'http://unitsofmeasure.org'`
us-core-4 | best practice | Observation.value[x] | SHOULD use Snomed CT for coded Results | `ofType(CodeableConcept).coding.system.empty() or (ofType(CodeableConcept).coding.system contains 'http://snomed.info/sct')`
us-core-22 | error | Observation.referenceRange | SHALL use UCUM for coded quantity units. | `(low.system.empty() or low.system = 'http://unitsofmeasure.org') and (high.system.empty() or high.system = 'http://unitsofmeasure.org')`

Differential View

This structure is derived from USCoreObservationClinicalResultProfile

Name | Flags | Card. | Type | Description & Constraints Filter: Bindings Constraints Obligations
--- | --- | --- | --- | ---
Observation |  | 0..* | USCoreObservationClinicalResultProfile | Measurements and simple assertions
meta | S | 0..1 | Meta | Metadata about the resource
lastUpdated | S | 0..1 | instant | When the resource last changed
Slices for category |  |  |  | Content/Rules for all slices
category:us-core | S | 1..1 | CodeableConcept | Classification of type of observation Required Pattern: At least the following
coding |  | 1..* | Coding | Code defined by a terminology system Fixed Value: (Complex)
system |  | 1..1 | uri | Identity of the terminology system Fixed Value: http://terminology.hl7.org/CodeSystem/observation-category
code |  | 1..1 | code | Symbol in syntax defined by the system Fixed Value: laboratory
code | S | 1..1 | CodeableConcept | Laboratory Test Name Binding: US Core Laboratory Test Codes (extensible): Laboratory LOINC Codes
text |  | 0..1 | string | 𝗔𝗗𝗗𝗜𝗧𝗜𝗢𝗡𝗔𝗟 𝗨𝗦𝗖𝗗𝗜: The name of the test that was performed.
value[x] | S C | 0..1 |  | Result Value Constraints: us-core-4
valueQuantity |  |  | Quantity S |
valueCodeableConcept |  |  | CodeableConcept S |
valueString |  |  | string S |
valueBoolean |  |  | boolean |
valueInteger |  |  | integer |
valueRange |  |  | Range |
valueRatio |  |  | Ratio |
valueSampledData |  |  | SampledData |
valueTime |  |  | time |
valueDateTime |  |  | dateTime |
valuePeriod |  |  | Period |
interpretation | S | 0..* | CodeableConcept | Result interpretation Binding: ObservationInterpretationCodes (extensible): Observation Interpretation Codes
specimen | S | 0..1 | Reference(US Core Specimen Profile) | Specimen used for this observation
referenceRange | S C | 0..* | BackboneElement | Result reference range Constraints: us-core-22
Documentation for this format

#### Terminology Bindings (Differential)

Path | Status | Usage | ValueSet | Version | Source
Observation.code | Base | extensible | US Core Laboratory Test Codes | 📦8.0.1 | This IG
Observation.interpretation | Base | extensible | Observation Interpretation Codes | 📦4.0.1 | FHIR Std.

#### Constraints

Id | Grade | Path(s) | Description | Expression
us-core-4 | best practice | Observation.value[x] | SHOULD use Snomed CT for coded Results | `ofType(CodeableConcept).coding.system.empty() or (ofType(CodeableConcept).coding.system contains 'http://snomed.info/sct')`
us-core-22 | error | Observation.referenceRange | SHALL use UCUM for coded quantity units. | `(low.system.empty() or low.system = 'http://unitsofmeasure.org') and (high.system.empty() or high.system = 'http://unitsofmeasure.org')`

Snapshot View

Name | Flags | Card. | Type | Description & Constraints Filter: Bindings Constraints Obligations
--- | --- | --- | --- | ---
Observation | C | 0..* | USCoreObservationClinicalResultProfile | Measurements and simple assertions Constraints: obs-6, obs-7, us-core-2
id | Σ | 0..1 | id | Logical id of this artifact
meta | S Σ | 0..1 | Meta | Metadata about the resource
id |  | 0..1 | string | Unique id for inter-element referencing
extension |  | 0..* | Extension | Additional content defined by implementations Slice: Unordered, Open by value:url
versionId | Σ | 0..1 | id | Version specific identifier
lastUpdated | S Σ | 0..1 | instant | When the resource last changed
source | Σ | 0..1 | uri | Identifies where the resource comes from
profile | Σ | 0..* | canonical(StructureDefinition) | Profiles this resource claims to conform to
security | Σ | 0..* | Coding | Security Labels applied to this resource Binding: All Security Labels (extensible): Security Labels from the Healthcare Privacy and Security Classification System.
tag | Σ | 0..* | Coding | Tags applied to this resource Binding: CommonTags (example): Codes that represent various types of tags, commonly workflow-related; e.g. "Needs review by Dr. Jones".
implicitRules | ?!Σ | 0..1 | uri | A set of rules under which this content was created
language |  | 0..1 | code | Language of the resource content Binding: CommonLanguages (preferred): A human language.
Additional Bindings | Purpose
AllLanguages | Max Binding
text |  | 0..1 | Narrative | Text summary of the resource, for human interpretation This profile does not constrain the narrative in regard to content, language, or traceability to data elements
contained |  | 0..* | Resource | Contained, inline Resources
extension |  | 0..* | Extension | Additional content defined by implementations
modifierExtension | ?! | 0..* | Extension | Extensions that cannot be ignored
identifier | Σ | 0..* | Identifier | Business Identifier for observation
basedOn | Σ | 0..* | Reference(CarePlan | DeviceRequest | ImmunizationRecommendation | MedicationRequest | NutritionOrder | ServiceRequest) | Fulfills plan, proposal or order
partOf | Σ | 0..* | Reference(MedicationAdministration | MedicationDispense | MedicationStatement | Procedure | Immunization | ImagingStudy) | Part of referenced event
status | ?!S Σ | 1..1 | code | registered | preliminary | final | amended + Binding: ObservationStatus (required): Codes providing the status of an observation.
Slices for category | S | 1..* | CodeableConcept | Classification of type of observation Slice: Unordered, Open by value:$this Binding: ObservationCategoryCodes (preferred): Codes for high level observation categories.
category:us-core | S | 1..1 | CodeableConcept | Classification of type of observation Binding: US Core Clinical Result Observation Category (required): Note that other codes are permitted, see Required Bindings When Slicing by Value Sets Required Pattern: At least the following
id |  | 0..1 | string | Unique id for inter-element referencing
extension |  | 0..* | Extension | Additional content defined by implementations
coding |  | 1..* | Coding | Code defined by a terminology system Fixed Value: (Complex)
id |  | 0..1 | string | Unique id for inter-element referencing
extension |  | 0..* | Extension | Additional content defined by implementations
system |  | 1..1 | uri | Identity of the terminology system Fixed Value: http://terminology.hl7.org/CodeSystem/observation-category
version |  | 0..1 | string | Version of the system - if relevant
code |  | 1..1 | code | Symbol in syntax defined by the system Fixed Value: laboratory
display |  | 0..1 | string | Representation defined by the system
userSelected |  | 0..1 | boolean | If this coding was chosen directly by the user
text |  | 0..1 | string | Plain text representation of the concept
code | S Σ | 1..1 | CodeableConcept | Laboratory Test Name Binding: US Core Laboratory Test Codes (extensible): Laboratory LOINC Codes
id |  | 0..1 | string | Unique id for inter-element referencing
extension |  | 0..* | Extension | Additional content defined by implementations Slice: Unordered, Open by value:url
coding | Σ | 0..* | Coding | Code defined by a terminology system
text | Σ | 0..1 | string | 𝗔𝗗𝗗𝗜𝗧𝗜𝗢𝗡𝗔𝗟 𝗨𝗦𝗖𝗗𝗜: The name of the test that was performed.
subject | S Σ | 1..1 | Reference(US Core Patient Profile S | Group | Device | US Core Location Profile) | Who and/or what the observation is about
focus | Σ | 0..* | Reference(Resource) | What the observation is about, when it is not about the subject of record
encounter | S Σ | 0..1 | Reference(US Core Encounter Profile) | Encounter associated with Observation
effective[x] | S Σ C | 0..1 |  | Clinically relevant time/time-period for observation Constraints: us-core-1
effectiveDateTime |  |  | dateTime S |
effectivePeriod |  |  | Period |
effectiveTiming |  |  | Timing |
effectiveInstant |  |  | instant |
issued | Σ | 0..1 | instant | Date/Time this version was made available
performer | S Σ | 0..* | Reference(US Core Practitioner Profile S | US Core Organization Profile | US Core Patient Profile | PractitionerRole | US Core CareTeam Profile | US Core RelatedPerson Profile) | Who is responsible for the observation
value[x] | S Σ C | 0..1 |  | Result Value Constraints: us-core-3, us-core-4
valueQuantity |  |  | Quantity S |
valueCodeableConcept |  |  | CodeableConcept S |
valueString |  |  | string S |
valueBoolean |  |  | boolean |
valueInteger |  |  | integer |
valueRange |  |  | Range |
valueRatio |  |  | Ratio |
valueSampledData |  |  | SampledData |
valueTime |  |  | time |
valueDateTime |  |  | dateTime |
valuePeriod |  |  | Period |
dataAbsentReason | S C | 0..1 | CodeableConcept | Why the result is missing Binding: DataAbsentReason (extensible): Codes specifying why the result (Observation.value[x]) is missing.
interpretation | S | 0..* | CodeableConcept | Result interpretation Binding: ObservationInterpretationCodes (extensible): Observation Interpretation Codes
note |  | 0..* | Annotation | Comments about the observation
bodySite |  | 0..1 | CodeableConcept | Observed body part Binding: SNOMEDCTBodyStructures (example): Codes describing anatomical locations. May include laterality.
method |  | 0..1 | CodeableConcept | How it was done Binding: ObservationMethods (example): Methods for simple observations.
specimen | S | 0..1 | Reference(US Core Specimen Profile) | Specimen used for this observation
device |  | 0..1 | Reference(Device | DeviceMetric) | (Measurement) Device
referenceRange | S C | 0..* | BackboneElement | Result reference range Constraints: obs-3, us-core-22
id |  | 0..1 | string | Unique id for inter-element referencing
extension |  | 0..* | Extension | Additional content defined by implementations
modifierExtension | ?!Σ | 0..* | Extension | Extensions that cannot be ignored even if unrecognized
low | C | 0..1 | SimpleQuantity(4.0.1) | Low Range, if relevant
high | C | 0..1 | SimpleQuantity(4.0.1) | High Range, if relevant
type |  | 0..1 | CodeableConcept | Reference range qualifier Binding: ObservationReferenceRangeMeaningCodes (preferred): Code for the meaning of a reference range.
appliesTo |  | 0..* | CodeableConcept | Reference range population Binding: ObservationReferenceRangeAppliesToCodes (example): Codes identifying the population the reference range applies to.
age |  | 0..1 | Range | Applicable age range, if relevant
text |  | 0..1 | string | Text based reference range in an observation
hasMember | Σ | 0..* | Reference(Observation | QuestionnaireResponse | MolecularSequence) | Related resource that belongs to the Observation group
derivedFrom | Σ | 0..* | Reference(DocumentReference | ImagingStudy | Media | QuestionnaireResponse | Observation | MolecularSequence) | Related measurements the observation is made from
component | Σ | 0..* | BackboneElement | Component results
id |  | 0..1 | string | Unique id for inter-element referencing
extension |  | 0..* | Extension | Additional content defined by implementations
modifierExtension | ?!Σ | 0..* | Extension | Extensions that cannot be ignored even if unrecognized
code | Σ | 1..1 | CodeableConcept | Type of component observation (code / type) Binding: LOINCCodes (example): Codes identifying names of simple observations.
value[x] | Σ | 0..1 |  | Actual component result
valueQuantity |  |  | Quantity |
valueCodeableConcept |  |  | CodeableConcept |
valueString |  |  | string |
valueBoolean |  |  | boolean |
valueInteger |  |  | integer |
valueRange |  |  | Range |
valueRatio |  |  | Ratio |
valueSampledData |  |  | SampledData |
valueTime |  |  | time |
valueDateTime |  |  | dateTime |
valuePeriod |  |  | Period |
dataAbsentReason | C | 0..1 | CodeableConcept | Why the component result is missing Binding: DataAbsentReason (extensible): Codes specifying why the result (Observation.value[x]) is missing.
interpretation |  | 0..* | CodeableConcept | High, low, normal, etc. Binding: ObservationInterpretationCodes (extensible): Codes identifying interpretations of observations.
referenceRange |  | 0..* | See referenceRange (Observation) | Provides guide for interpretation of component result
Documentation for this format

#### Terminology Bindings

Path | Status | Usage | ValueSet | Version | Source
Observation.meta.security | Base | extensible | SecurityLabels | 📍4.0.1 | FHIR Std.
Observation.meta.tag | Base | example | Common Tags | 📍4.0.1 | FHIR Std.
Observation.language | Base | preferred | Common Languages | 📍4.0.1 | FHIR Std.
Observation.status | Base | required | ObservationStatus | 📍4.0.1 | FHIR Std.
Observation.category | Base | preferred | Observation Category Codes | 📍4.0.1 | FHIR Std.
Observation.category:us-core | Base | required | US Core Clinical Result Observation Category | 📦8.0.1 | This IG
Observation.code | Base | extensible | US Core Laboratory Test Codes | 📦8.0.1 | This IG
Observation.dataAbsentReason | Base | extensible | DataAbsentReason | 📍4.0.1 | FHIR Std.
Observation.interpretation | Base | extensible | Observation Interpretation Codes | 📦4.0.1 | FHIR Std.
Observation.bodySite | Base | example | SNOMED CT Body Structures | 📍4.0.1 | FHIR Std.
Observation.method | Base | example | Observation Methods | 📍4.0.1 | FHIR Std.
Observation.referenceRange.​type | Base | preferred | Observation Reference Range Meaning Codes | 📍4.0.1 | FHIR Std.
Observation.referenceRange.​appliesTo | Base | example | Observation Reference Range Applies To Codes | 📍4.0.1 | FHIR Std.
Observation.component.​code | Base | example | LOINC Codes | 📍4.0.1 | FHIR Std.
Observation.component.​dataAbsentReason | Base | extensible | DataAbsentReason | 📍4.0.1 | FHIR Std.
Observation.component.​interpretation | Base | extensible | Observation Interpretation Codes | 📍4.0.1 | FHIR Std.

#### Constraints

Id | Grade | Path(s) | Description | Expression
dom-2 | error | Observation | If the resource is contained in another resource, it SHALL NOT contain nested Resources | `contained.contained.empty()`
dom-3 | error | Observation | If the resource is contained in another resource, it SHALL be referred to from elsewhere in the resource or SHALL refer to the containing resource | `contained.where((('#'+id in (%resource.descendants().reference | %resource.descendants().as(canonical) | %resource.descendants().as(uri) | %resource.descendants().as(url))) or descendants().where(reference = '#').exists() or descendants().where(as(canonical) = '#').exists() or descendants().where(as(canonical) = '#').exists()).not()).trace('unmatched', id).empty()`
dom-4 | error | Observation | If a resource is contained in another resource, it SHALL NOT have a meta.versionId or a meta.lastUpdated | `contained.meta.versionId.empty() and contained.meta.lastUpdated.empty()`
dom-5 | error | Observation | If a resource is contained in another resource, it SHALL NOT have a security label | `contained.meta.security.empty()`
dom-6 | best practice | Observation | A resource should have narrative for robust management | `text.`div`.exists()`
ele-1 | error | **ALL** elements | All FHIR elements must have a @value or children | `hasValue() or (children().count() > id.count())`
ext-1 | error | **ALL** extensions | Must have either extensions or value[x], not both | `extension.exists() != value.exists()`
obs-3 | error | Observation.referenceRange | Must have at least a low or a high or text | `low.exists() or high.exists() or text.exists()`
obs-6 | error | Observation | dataAbsentReason SHALL only be present if Observation.value[x] is not present | `dataAbsentReason.empty() or value.empty()`
obs-7 | error | Observation | If Observation.code is the same as an Observation.component.code then the value element associated with the code SHALL NOT be present | `value.empty() or component.code.where(coding.intersect(%resource.code.coding).exists()).empty()`
us-core-1 | error | Observation.effective[x] | Datetime must be at least to day. | `$this is dateTime implies $this.toString().length() >= 10`
us-core-2 | error | Observation | If there is no component or hasMember element then either a value[x] or a data absent reason must be present | `(component.empty() and hasMember.empty()) implies (dataAbsentReason.exists() or value.exists())`
us-core-3 | error | Observation.value[x] | SHALL use UCUM for coded quantity units. | `ofType(Quantity).system.empty() or ofType(Quantity).system = 'http://unitsofmeasure.org'`
us-core-4 | best practice | Observation.value[x] | SHOULD use Snomed CT for coded Results | `ofType(CodeableConcept).coding.system.empty() or (ofType(CodeableConcept).coding.system contains 'http://snomed.info/sct')`
us-core-22 | error | Observation.referenceRange | SHALL use UCUM for coded quantity units. | `(low.system.empty() or low.system = 'http://unitsofmeasure.org') and (high.system.empty() or high.system = 'http://unitsofmeasure.org')`

This structure is derived from USCoreObservationClinicalResultProfile

Summary

Mandatory: 1 element
Must-Support: 8 elements

Structures

This structure refers to these other structures:

- US Core Specimen Profile (http://hl7.org/fhir/us/core/StructureDefinition/us-core-specimen)

Maturity: 3

Other representations of profile: CSV, Excel, Schematron

### 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 for a complete list of supported RESTful interactions for this IG.

- See the Scopes Format section for a description of the SMART scopes syntax.
- See the Search Syntax section for a description of the US Core search syntax.
- See the General Requirements section for additional rules and expectations when a Server requires status parameters.
- See the General Guidance section for additional guidance on searching for multiple patients.

#### US Core Scopes

Servers providing access to laboratory data SHALL support these US Core SMART Scopes:

- resource level scopes: `<patient|user|system>/Observation.rs`

- granular scopes: `<patient|user|system>/Observation.rs?category=http://terminology.hl7.org/CodeSystem/observation-category|laboratory`

#### Mandatory Search Parameters:

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

1. SHALL support searching using the combination of the `patient` and `category` 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=http://terminology.hl7.org/CodeSystem/observation-category|laboratory

   Implementation Notes: Fetches a bundle of all Observation resources for the specified patient and a category code = `laboratory` (how to search by reference and how to search by token)

2. SHALL support searching using the combination of the `patient` and `code` 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|2339-0
   2. GET [base]/Observation?patient=1134281&amp;code=http://loinc.org|2339-0,http://loinc.org|25428-4,http://loinc.org|2514-8

   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 and how to search by token)

3. SHALL support searching using the combination of the `patient` and `category` and `date` 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=http://terminology.hl7.org/CodeSystem/observation-category|laboratory&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 and how to search by token and how to search by date)

#### Optional Search Parameters:

The following search parameter combinations SHOULD be supported:

1. SHOULD support searching using the combination of the `patient` and `category` and `status` 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=http://terminology.hl7.org/CodeSystem/observation-category|laboratory&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 and how to search by token)

2. SHOULD support searching using the combination of the `patient` and `category` and `_lastUpdated` 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&http://terminology.hl7.org/CodeSystem/observation-category|laboratory&_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. (how to search by reference and how to search by token and how to search by date)

3. SHOULD support searching using the combination of the `patient` and `code` and `date` 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|2339-0&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 and how to search by token and how to search by date)