Interactions with the Terminology Service
Determining the proper code, system and unit for Quantity
Given an observation code
and corresponding system
from the ValueSet ehealth-observation-codes, how does one then determine how to specify an observed quantity or reference range? The following describes how to obtain values to set inQuantity.code
, .system
and .unit
.
To get values forQuantity.code
andQuantity.system
use the ConceptMap conceptmap-obs-code-to-ucum as follows:
Call
$translate
on the givencode
andsystem
:GET <base-url>/fhir/ConceptMap/$translate?system=<system>&code=<code>
On match found, the values to use in
Quantity.code
andQuantity.system
are the matching concept’scode
andsystem
, respectively, where the source ConceptMap is “http://ehealth.sundhed.dk/ConceptMap/conceptmap-obs-code-to-ucum” (see example response below):
Example request and response on $translate on conceptmap-obs-code-to-ucum
Request:
GET <base-url>/fhir/ConceptMap/$translate?system=urn:oid:1.2.208.176.2.1&code=NPU03804
Response:
{ "resourceType": "Parameters", "parameter": [ { "name": "result", "valueBoolean": true }, { "name": "message", "valueString": "Matches found!" }, { "name": "match", "part": [ { "name": "equivalence", "valueCode": "specializes" }, { "name": "concept", "valueCoding": { "system": "http://unitsofmeasure.org", "code": "kg", "display": "kilogram" } }, { "name": "source", "valueUri": "http://ehealth.sundhed.dk/ConceptMap/conceptmap-obs-code-to-ucum" } ] } ] }
To get the corresponding and printable value for Quantity.unit
, use the ConceptMap conceptmap-ucum-to-printsymbol as follows:
Call
$translate
on the givensystem
andcode
determined in the response above:GET <base-url>/fhir/ConceptMap/$translate?target=http://ehealth.sundhed.dk/vs/ehealth-ucum-printsymbol-supplement&code=<code>&system=<system>
On match found, extract the matching concept (see example response below).
Call
$lookup
on the matching (CodeSystem)system
andcode
:GET <base-url>/fhir/CodeSystem/$lookup?system=http://ehealth.sundhed.dk/cs/ehealth-ucum-printsymbol-supplement&code=<code>
On match found, the value to use in
Quantity.unit
is the matching concept’sdesignation.value
where thedesignation.language=da
(see example response below). If there is no such designation, the printable value inQuantity.unit
shall be left empty.
The $lookup does not return designation on eHealth Infrastructure Release 4 and other releases prior to Release 5.
Example request and response on $translate on conceptmap-ucum-to-printsymbol
Request (Note that URL-encoding of percent as code is used):
GET <base-url>/fhir/ConceptMap/$translate?target=http://ehealth.sundhed.dk/vs/ehealth-ucum-printsymbol-supplement&code=%25&system=http://unitsofmeasure.org
Response:
{ "resourceType": "Parameters", "parameter": [ { "name": "result", "valueBoolean": true }, { "name": "message", "valueString": "Matches found!" }, { "name": "match", "part": [ { "name": "equivalence", "valueCode": "specializes" }, { "name": "concept", "valueCoding": { "system": "http://ehealth.sundhed.dk/cs/ehealth-ucum-printsymbol-supplement", "code": "%", "display": "percent" } }, { "name": "source", "valueUri": "http://ehealth.sundhed.dk/ConceptMap/conceptmap-ucum-to-printsymbol" } ] } ] }
Example request and response on $lookup on ehealth-ucum-printsymbol-supplement
Request (Note that URL-encoding of percent as code is used):
GET <base-url>/fhir/CodeSystem/$lookup?system=http://ehealth.sundhed.dk/cs/ehealth-ucum-printsymbol-supplement&code=%25
Response:
{ "resourceType": "Parameters", "parameter": [ { "name": "name", "valueString": "UCUMPrintSymbolSupplement" }, { "name": "version", "valueString": "0.6.0" }, { "name": "display", "valueString": "percent" }, { "name": "abstract", "valueBoolean": false }, { "name": "designation", "part": [ { "name": "language", "valueCode": "da" }, { "name": "use" }, { "name": "value", "valueString": "%" } ] } ] }
Determining whether to provide measurement as integer or decimal
This section is under construction
The approach described in this section is pending customer’s approval and is possibly subject to change.
Given an observation code
and corresponding system
from the ValueSet ehealth-observation-codes, how does one determine whether an observed quantity or reference range shall be stated as an integer or decimal? While a particular device might produce a decimal with a given precision for a measure, it is up to the client/solution to convert to the form expected by the infrastructure. Whether integer or decimal, the value is set inQuantity.value
.
To determine whether to use integer or decimal, use the ConceptMap conceptmap-obs-code-to-type as follows:
Call
$translate
on the givencode
andsystem
:GET <base-url>/fhir/ConceptMap/$translate?system=<system>&code=<code>&target=TBD TBD TBD TBD
On match found, indication of whether to use integer or decimal are the matching concept’s
code
andsystem
, respectively, where the source ConceptMap is “http://ehealth.sundhed.dk/ConceptMap/conceptmap-obs-code-to-type” (see example response below).The codes
integer
anddecimal
insystem http://hl7.org/fhir/data-types
signify that the observed value or reference range shall be given as integer and decimal, respectively.
Example request and response on $translate on conceptmap-obs-code-to-type
Request:
GET <base-url>/fhir/ConceptMap/$translate?system=urn:oid:1.2.208.176.2.1&code=NPU03804&target=
Response:
TBD