hl7.org/fhir/R4

Query a FHIR R4 server using GraphQL to retrieve a patient with selected fields from nested resources in a single request, reducing over-fetching compared to REST

Implement FHIR Measure and MeasureReport resources to compute a quality measure (e.g., proportion of diabetic patients with HbA1c tested) and report results programmatically

Implement FHIR NamingSystem resources to manage identifier namespaces and resolve patient identifiers across health systems using the $translate operation

Build a FHIR EpisodeOfCare resource to model a longitudinal care episode for a patient with a chronic condition, linking it to Encounters and tracking the episode lifecycle

Implement FHIR Group resource management to define a patient cohort for population health queries and use the Group as the subject of a Bulk Data $export

Use the FHIR $convert operation to transform a resource from one format or version to another, and handle version-specific differences between FHIR R4 and R4B resources

Validate a LOINC code against a FHIR ValueSet using the terminology $validate-code operation

Retrieve a complete patient clinical summary using the $everything operation

Perform conditional create and conditional update to avoid duplicate FHIR resources

Distinguish transaction vs batch Bundle semantics for atomic vs independent operations

Use _include and _revinclude to retrieve referenced resources in a single search request

Record FHIR Provenance and AuditEvent resources for data lineage and access logging

Enforce patient Consent resource policies for data sharing restrictions in a FHIR server