Overview

The US Core Observation Clinical Test Result Profile is based upon the core FHIR Observation Resource, and, along with the US Core DiagnosticReport Profile for Report and Note exchange, meets the US Core Data for Interoperability (USCDI) v2 ‘Clinical Tests’ requirements. Clinical tests includes non-imaging and non-laboratory tests performed on a patient that results in structured or unstructured (narrative) findings specific to the patient, such as electrocardiogram (ECG), visual acuity exam, macular exam, or graded exercise testing (GXT), to facilitate the diagnosis and management of conditions.

The following are example usage scenarios for the this profile:

Example Usage Scenarios:

The following are example usage scenarios for the this profile:

Query for non-imaging and non-laboratory tests results for a patient
Record or update clinical tests results belonging to a Patient

Each Observation has next elements:

a status
a category code of clinical-test
a LOINC code, if available, which tells you what is being measured
a patient

Each Observation supports next elements:

a time indicating when the measurement was taken
a result value or a reason why the data is absent
- if the result value is a numeric quantity, a standard UCUM unit

Profile specific implementation guidance:

This profile defines a Valueset based on a starter set of example clinical test LOINC codes identified in the Appendix B in US Core Data for Interoperability (USCDI) Task Force 2021 HITAC Phase 3 Recommendations Report Letter. It is not intended to be complete and implementers are expected include other LOINC or other codes to meet their business needs.
The Observation.category element provides an efficient way of restricting search on observations to “clinical-test” observations. 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 LOINC code
- providing a more specific code , a SNOMED CT concept, or system specific codes in addition to the ‘clinical-test’ category code.
Systems SHOULD support Observation.effectivePeriod to accurately represent procedure tests that are collected over a period of time .
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.
See the General Guidance Section for further guidance on using UCUM
For imaging and laboratory tests the corresponding US Core Diagnostic Imaging Result Observation Profile and US Core Laboratory Result Observation Profile should be used instead.

This resource conforms to USCDI V2 profile for Observation - refers to US Core Observation Profile for Report and Note Exchange. Observation response will be provided in JSON (refers to Capability Statement) format as per FHIR standard R4 version.

Must support elements, mandatory and optional search parameters

Observationmust support these elements:

status
Slices for category
-category:clinical-test
code
subject
effectiveDateTime
valueQuantity
valueCodeableConcept
valueString
dataAbsentReason

The syntax used to describe the interactions is described here.

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

SHALL support searching using the combination of the patient and category search parameters:

GET [base]/Observation?patient={Type/}[id]&category={system|}[code]&category=http://terminology.hl7.org/CodeSystem/observation-category|clinical-test

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],...}

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={system|}[code]&date={gt|lt|ge|le}[date]{&date={gt|lt|ge|le}[date]&...}

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

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|clinical-test&status={system|}[code]{,{system|}[code],...}

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]&...}

The response to any search operation is always a list of resources in a Bundle or an Operation Outcome.

Diagnostic Report by Patient and Category

Search for ObservaDiagnosticReportstion by combination patient and category.

METHOD GET

[base url]/Observation?patient={Type/}[id]&category=http://terminology.hl7.org/CodeSystem/observation-category|clinical-test

PARAMS
[base url] - FHIR base url
{Type/} - optional reference type
[id] - Id for the Patient

HEADERS

The Authorization token SHALL be obtained during Authentication and Authorization process. Go to Authentication and Authorization for further details.

Header	Type	Required/Optional	Value
Authorization	string	required	`Bearer <token>`

RESPONSES

Code	Description	Comment
200	OK	The request was processed successfully
400	Bad request	Invalid request parameters or FHIR operation outcome resource returned
401	Unauthorized	This code indicates that the client request has not been completed because it lacks valid authentication credentials for the requested resource
404	no Route matched with those values	The request was able to communicate with a given server, but the server could not find what was requested
500	Internal Server Error	The server has encountered a situation it doesn't know how to handle

EXAMPLE:

curl --location --request GET 'https://sandbox.fhir.elationemr.com/fhir/Observation?patient=Patient/c5137fa5-3216-b12a-cbbc-a0c6bef361g7&category=http://terminology.hl7.org/CodeSystem/observation-category|laboratory' \
--header 'Authorization: Bearer fe1cd986-1ac7-4c26-b8b3-d632a48408fd'

Observation by Patient and Code

Search for Observation by combination patient and code.

METHOD GET

[base url]/Observation?patient={Type/}[id]&code={system|}[code]

PARAMS
[base url] - FHIR base url
{Type/} - optional reference type
[id] - Id for the Patient
{system|} - The system for the category, e.g. http://loinc.org
{code} - code for observation in the system, e.g. 44974-4

HEADERS

The Authorization token SHALL be obtained during Authentication and Authorization process. Goto Authentication and Authorization for further details.

Header	Type	Required/Optional	Value
Authorization	string	required	`Bearer <token>`

RESPONSES

Code	Description	Comment
200	OK	The request was processed successfully
400	Bad request	Invalid request parameters or FHIR operation outcome resource returned
401	Unauthorized	This code indicates that the client request has not been completed because it lacks valid authentication credentials for the requested resource
404	no Route matched with those values	The request was able to communicate with a given server, but the server could not find what was requested
500	Internal Server Error	The server has encountered a situation it doesn't know how to handle

EXAMPLE:

curl --location --request GET 'https://sandbox.fhir.elationemr.com/fhir/Observation?patient=Patient/c5137fa5-3216-b12a-cbbc-a0c6bef361g7&code=http://loinc.org|44974-4,http://loinc.org|44963-7,http://loinc.org|8601-7' \
--header 'Authorization: Bearer fe1cd986-1ac7-4c26-b8b3-d632a48408fd'

Observation by Patient and Category and Date

Search for Observations by combination patient and category and date.

METHOD GET

[base url]/Observation?patient={Type/}[id]&category=http://terminology.hl7.org/CodeSystem/observation-category|clinical-test&date={gt|lt|ge|le}[date]{&date={gt|lt|ge|le}[date]&...}

PARAMS
[base url] - FHIR base url
{Type/} - optional reference type
[id] - Id for the Patient
{system|} - The system for the category, e.g. http://loinc.org
{code} - Code for observation in the system, e.g. 24323-8
[date] - Filter's date
{gt|lt|ge|le} - Search modifier gr or lt or ge or le. Specification how to search by date in FHIR

HEADERS

The Authorization token SHALL be obtained during Authentication and Authorization process. Go to Authentication and Authorization for further details.

Header	Type	Required/Optional	Value
Authorization	string	required	`Bearer <token>`

RESPONSES

Code	Description	Comment
200	OK	The request was processed successfully
400	Bad request	Invalid request parameters or FHIR operation outcome resource returned
401	Unauthorized	This code indicates that the client request has not been completed because it lacks valid authentication credentials for the requested resource
404	no Route matched with those values	The request was able to communicate with a given server, but the server could not find what was requested
500	Internal Server Error	The server has encountered a situation it doesn't know how to handle

EXAMPLE:

curl --location --request GET 'https://sandbox.fhir.elationemr.com/fhir/Observation?patient=Patient/c5137fa5-3216-b12a-cbbc-a0c6bef361g7&category=http://terminology.hl7.org/CodeSystem/observation-category|clinical-test&date=ge2010-01-14T00:00:00Z' \
--header 'Authorization: Bearer fe1cd986-1ac7-4c26-b8b3-d632a48408fd'

Observation by Patient and Category and Status

Search for Observations by combination patient and Category and Status.

METHOD GET

[base url]/Observation?patient={Type/}[id]&category=http://terminology.hl7.org/CodeSystem/observation-category|clinical-test&status={system|}[code]{,{system|}[code],...}

PARAMS
[base url] - FHIR base url
{Type/} - optional reference type
[id] - Id for the Patient
{system|} - The system for the category, e.g. http://loinc.org
{code} - code for observation in the system, e.g. final

HEADERS

The Authorization token SHALL be obtained during Authentication and Authorization process. Go to Authentication and Authorization for further details.

Header	Type	Required/Optional	Value
Authorization	string	required	`Bearer <token>`

RESPONSES

Code	Description	Comment
200	OK	The request was processed successfully
400	Bad request	Invalid request parameters or FHIR operation outcome resource returned
401	Unauthorized	This code indicates that the client request has not been completed because it lacks valid authentication credentials for the requested resource
404	no Route matched with those values	The request was able to communicate with a given server, but the server could not find what was requested
500	Internal Server Error	The server has encountered a situation it doesn't know how to handle

EXAMPLE:

curl --location --request GET 'https://sandbox.fhir.elationemr.com/fhir/Observation?patient=Patient/c5137fa5-3216-b12a-cbbc-a0c6bef361g7&category=http://terminology.hl7.org/CodeSystem/observation-category|clinical-test&status=final' \
--header 'Authorization: Bearer fe1cd986-1ac7-4c26-b8b3-d632a48408fd'

Observation by Patient and Code and Date

Search for Observations by combination patient and code and date.

METHOD GET

[base url]/ObsDiagnosticReportervation?patient={Type/}[id]&code={system|}[code]{,{system|}[code],...}&date={gt|lt|ge|le}[date]{&date={gt|lt|ge|le}[date]&...}

PARAMS
[base url] - FHIR base url
{Type/} - optional reference type
[id] - Id for the Patient
{system|} - The system for the category, e.g. http://loinc.org
{code} - code for observation in the system, e.g. 2339-0
[date] - Filter's date
{gt|lt|ge|le} - Search modifier gr or lt or ge or le. Specification how to search by date in FHIR

HEADERS

The Authorization token SHALL be obtained during Authentication and Authorization process. Goto Authentication and Authorization for further details.

Header	Type	Required/Optional	Value
Authorization	string	required	`Bearer <token>`

RESPONSES

Code	Description	Comment
200	OK	The request was processed successfully
400	Bad request	Invalid request parameters or FHIR operation outcome resource returned
401	Unauthorized	This code indicates that the client request has not been completed because it lacks valid authentication credentials for the requested resource
404	no Route matched with those values	The request was able to communicate with a given server, but the server could not find what was requested
500	Internal Server Error	The server has encountered a situation it doesn't know how to handle

EXAMPLE:

curl --location --request GET 'https://sandbox.fhir.elationemr.com/fhir/Observation?patient=Patient/c5137fa5-3216-b12a-cbbc-a0c6bef361g7&code=http://loinc.org|2339-0&date=ge2019-01-14T00:00:00Z' \
--header 'Authorization: Bearer fe1cd986-1ac7-4c26-b8b3-d632a48408fd'