C-CDA on FHIR, published by HL7 International / Cross-Group Projects. This guide is not an authorized publication; it is the continuous build for version 2.0.0-ballot built by the FHIR (HL7® FHIR® Standard) CI Build. This version is based on the current content of https://github.com/HL7/ccda-on-fhir/ and changes regularly. See the Directory of published versions
 FHIR US Core → C-CDA Mapping
  FHIR US Core → C-CDA Mapping
  While multiple vendors participated in CDA → FHIR mappings at a connectathon, only a single vendor (Cerner/Oracle) has participated in the FHIR → CDA mapping. We welcome feedback on these mappings which represent less than a multi-vendor consensus at this time.
This page provides a mapping from FHIR to CDA. For the CDA to FHIR mapping, please refer to Allergies CDA → FHIR. For guidance on how to read the table below, see Reading the C-CDA ↔ FHIR Mapping Pages
| FHIR AllergyIntolerance | C-CDA¹ Allergy Intolerance observation | Transform Steps | 
|---|---|---|
| .identifier | /id | CDA id ↔ FHIR identifier | 
| .clinicalStatus | (act parent to observation) ../../statusCode & Allergy Status /entryRelationship/observation[code/@code="33999-4"]/value | FHIR clinicalStatus → CDA Allergy Status Observation value For more information on how status is managed in Allergy Concern Act wrapper, refer to C-CDA guidance, see 5.2.7.1 | 
| .type & .category | /value | FHIR type → CDA value FHIR category → CDA value | 
| .criticality | Criticality /entryRelationship/observation[code/@code="82606-5"]/value | CDA coding ↔ FHIR CodeableConcept FHIR criticality → CDA Criticality value | 
| .code | /participant/participantRole/playingEntity/code | Constraint: When FHIR concept is not a negated concept CDA coding ↔ FHIR CodeableConcept | 
| .code | /participant/participantRole/playingEntity/code or /value & set @negationInd="true" | Constraint: When FHIR concept represents general negated concept (e.g. no known allergy) FHIR code → CDA No Known Allergy In case where a specific refutation is coded (no latex allergy), use text or a mapped concept. | 
| .encounter | /entryRelationship[@typeCode="REFR"]/act/id | |
| .onsetDateTime | /effectiveTime/low | CDA ↔ FHIR Time/Dates | 
| .onsetPeriod.start | /effectiveTime/low | effectiveTime/high should not be mapped from onsetPeriod | 
| .recordedDate | /assignedAuthor/time | These are not necessarily the same author | 
| .recorder | /assignedAuthor | CDA ↔ FHIR Provenance Time and author are not necessarily the same | 
| Annotation .note | Comment Activity /entryRelationship/act[code/@code="48767-8"]/text | |
| .reaction.manifestation | Reaction /entryRelationship[@typeCode="MFST"]/observation/value | Both use SNOMED clinical findings with minor valueSet definition differences | 
| .reaction.onset | /effectiveTime/low | Constraint: This should only be used in event that AlleryIntolerance.onset was not available | 
| .reaction.severity | Severity /entryRelationship[@typeCode="MFST"]/observation/entryRelationship/observation[code/@code="SEV"]/value | FHIR severity → CDA severity value This should be nested in CDA within the respective allergic reaction observation | 
1. XPath abbrievated for C-CDA Allergy Intolerance as: 
 ClinicalDocument/component/structuredBody/component/section[code/@code="48765-2"]/entry/act/entryRelationship/observation
Note that these mappings have only been implemented by a single vendor to date.
As reviewed in the methodology, a more comprehensive review was performed via spreadsheets. These spreadsheets have been consolidated and further revised in the tables above but are provided for reference here