CH EMED (R4), published by HL7 Switzerland. This guide is not an authorized publication; it is the continuous build for version 5.0.0-ci-build built by the FHIR (HL7® FHIR® Standard) CI Build. This version is based on the current content of https://github.com/hl7ch/ch-emed/ and changes regularly. See the Directory of published versions

Relationship Between Documents

In order to represent the relationship between the individual eMedication documents and their resources (MedicationStatement, MedicationDispense, MedicationAdministration, MedicationRequest, Observation), extensions referencing the document and its resources are defined. These referencing mechanism is based on the usage of the identifiers from the document its resources.

The following figure illustrates the documents from the use case (DE, FR) and schematically shows this referencing, which depicts the relationship between the documents.

Note on the colors:
The background color of the resources reflects the medication (Triatec: orange, Beloc Zok: purple, Norvasc: blue).
The colors of the identifiers and the resource box should reflect the relationships/origins. Note that from use case step 2-3 onwards, the colors are repeated without a reference to the previous steps.

Fig.: Schematic overview of the relationship between the documents from the use case.

Identifiers

Identifier Format

In CH EMED it is specified to use an UUID as identifier, for both the document and resource identifiers.
For representing UUIDs the system needs to be urn:ietf:rfc:3986 as described here. The value has to start with urn:uuid:.

Document Identifier

Document identifier in 1-1 Medication Treatment Plan document:
Bundle.identifier/Composition.identifier

  "identifier" : {
    "system" : "urn:ietf:rfc:3986",
    "value" : "urn:uuid:7aa20b27-eac0-4fef-a7b9-b10196718b9f"
  }

Resource Identifier

Resource identifier in 1-1 Medication Treatment Plan document:
MedicationStatement.identifier (in this example the resource identifier has the same value as the document identifier, but it does not have to be that way)

  "identifier" : {
    "system" : "urn:ietf:rfc:3986",
    "value" : "urn:uuid:7aa20b27-eac0-4fef-a7b9-b10196718b9f"
  }

Referencing Extensions

Extension pairs are used in all the extensions (shown below) which are used to reference the documents and its resources.

Extension in 1-2 Medication Dispense document to reference the 1-1 Medication Treatment Plan document (externalDocumentId) and its MedicationStatement (id):
MedicationDispense.extension:treatmentPlan

  {
    "extension" : [
      {
        "url" : "id",
        "valueIdentifier" : {
            "system" : "urn:ietf:rfc:3986",
            "value" : "urn:uuid:7aa20b27-eac0-4fef-a7b9-b10196718b9f"
        }
      },
      {
        "url" : "externalDocumentId",
        "valueIdentifier" : {
            "system" : "urn:ietf:rfc:3986",
            "value" : "urn:uuid:7aa20b27-eac0-4fef-a7b9-b10196718b9f"
        }
      }
    ],
    "url" : "http://fhir.ch/ig/ch-emed/StructureDefinition/ch-emed-ext-treatmentplan"
  }

Extensions

The following table shows which extension can be used in which document. It shows which resource refers to which document (with its resource).