String

Coding

String to Coding

The transformation into a string is lackluster when coming from a coded value. To maintain some of the content, the coding should be parsed into the String and back as system::code, e.g., http://loinc.org::LP74849-8. This way, the most important fields are contained. The double colon (::) is introduced since it represents a unique combination that rarely appears in text.

When converting back, this may cause problems. Providers need to ensure that the freetext elements do not contain a :: or even skip the back-transformation of ::.
FHIRpath Cardinality Comment openEHR Cardinality Comment

code

0..1

string

1..1

openEHR→FHIR

system::code

0..1

FHIR→openEHR

string

1..1

openEHR→ FHIR if contains ::

version

0..1

-

-

display

0..1

-

-

userSelected

0..1

-

-

Identifier

Identifier to String

The transformation into a string is lackluster when coming from an identifier. To maintain some information, the identifier uses a double colon (::) since it represents a unique combination that rarely appears in text, similar to the above.

When converting back, this may cause problems. Providers need to ensure that the identifier elements do not contain a :: or even skip the back-transformation of ::.
FHIRpath Cardinality Comment openEHR Cardinality Comment

identifier.value

0..1

string

1..1

openEHR→FHIR

identifier

0..1

FHIR→openEHR encoded as identifier.system:: identifier.value

string

1..1

openEHR→ FHIR if contains ::

use

0..1

-

-

type

0..1

-

-

system

0..1

-

-

value

0..1

-

-

period

0..1

-

-

References

String to Reference

It is recommended to resolve non-clinical data references using the demographics see FHIRReferences .

The transformation into a string is lackluster when coming from a reference. The reference has three ways of representation in FHIR, listed below.

Identifier contained

In case the FHIR reference contains a direct identifier, see Identifier.

This is the transformation to be used for reference as a default if other fields are provided in the FHIR reference or when transforming from openEHR to FHIR.

Reference contained

In case the reference URL is contained, but no identifier is provided, nor is the reference resolvable as part of the Bundle or via a GET to the FHIR server sending it. Copying over the reference string is better than copying over nothing.

Providers have to decide if they accept this sort of encoding as part of their platform.
FHIRpath Cardinality Comment openEHR Cardinality Comment

reference

0..1

string

1..1

type

0..1

-

-

identifier

0..1

-

-

display

0..1

-

-

Reference contained and resolvable

In case the reference URL is contained and resolvable due to it being contained in the Bundle or via GET. The identifier is to be accessed as part of this reference, therefore being a Identifier to String transformation.