FHIRPath Specification, published by Implementable Technology Specifications WG. This guide is not an authorized publication; it is the continuous build for version 2.1.0 built by the FHIR (HL7® FHIR® Standard) CI Build. This version is based on the current content of https://github.com/HL7/FHIRPath/ and changes regularly. See the Directory of published versions
{
"resourceType" : "Observation",
"id" : "example",
"text" : // the mandatory quality flags:
{
"status" : "generated",
"div" : "<div xmlns=\"http://www.w3.org/1999/xhtml\"><p><b>Generated Narrative with Details</b></p><p><b>id</b>: example</p><p><b>status</b>: final</p><p><b>category</b>: Vital Signs <span>(Details : {http://terminology.hl7.org/CodeSystem/observation-category code 'vital-signs' = 'Vital Signs', given as 'Vital Signs'})</span></p><p><b>code</b>: Body Weight <span>(Details : {LOINC code '29463-7' = 'Body weight', given as 'Body Weight'}; {LOINC code '3141-9' = 'Body weight Measured', given as 'Body weight Measured'}; {SNOMED CT code '27113001' = 'Body weight', given as 'Body weight'}; {http://acme.org/devices/clinical-codes code 'body-weight' = 'body-weight', given as 'Body Weight'})</span></p><p><b>subject</b>: <a>Patient/example</a></p><p><b>encounter</b>: <a>Encounter/example</a></p><p><b>effective</b>: 28/03/2016</p><p><b>value</b>: 185 lbs<span> (Details: UCUM code [lb_av] = 'lb_av')</span></p></div>"
},
"status" : "final",
"category" : [
// category code is A code that classifies the general type of observation being made. This is used for searching, sorting and display purposes.
{
"coding" : [
{
"system" : "http://terminology.hl7.org/CodeSystem/observation-category",
"code" : "vital-signs",
"display" : "Vital Signs"
}
]
}
],
"code" : //
Observations are often coded in multiple code systems.
- LOINC provides codes of varying granularity (though not usefully more specific in this particular case) and more generic LOINCs can be mapped to more specific codes as shown here
- snomed provides a clinically relevant code that is usually less granular than LOINC
- the source system provides its own code, which may be less or more granular than LOINC
{
"coding" : [
// LOINC - always recommended to have a LOINC code
{
"system" : "http://loinc.org",
"code" : "29463-7",
"display" : "Body Weight"
},
// more generic methodless LOINC
{
"system" : "http://loinc.org",
"code" : "3141-9",
"display" : "Body weight Measured"
},
// translation is more specific method = measured LOINC
{
"system" : "http://snomed.info/sct",
"code" : "27113001",
"display" : "Body weight"
},
{
"system" : "http://acme.org/devices/clinical-codes",
"code" : "body-weight",
"display" : "Body Weight"
}
]
},
"subject" : // SNOMED CT Codes - becoming more common
// Also, a local code specific to the source system
{
🔗 "reference" : "Patient/example"
},
"effectiveDateTime" : "2016-03-28",
"valueQuantity" : // encounter>
<reference value="Encounter/example"/>
</encounter
// In FHIR, units may be represented twice. Once in the
agreed human representation, and once in a coded form.
Both is best, since it's not always possible to infer
one from the other in code.
When a computable unit is provided, UCUM (http://unitsofmeasure.org)
is always preferred, but it doesn't provide notional units (such as
"tablet"), etc. For these, something else is required (e.g. SNOMED CT)
{
"value" : 185,
"unit" : "lbs",
"system" : "http://unitsofmeasure.org",
"code" : "[lb_av]"
}
}