This page is part of the Common CQL Assets for FHIR (US-Based) (v1.0.0: Informative 1 - Informative) based on FHIR (HL7® FHIR® Standard) R4. This is the current published version in its permanent home (it will always be available at this URL). For a full list of available versions, see the Directory of published versions

Query Management

Page standards status: Informative

This topic provides query management guidance for implementers to support the use of CQL within FHIR artifacts such as questionnaires, typically from a DTR application. The functions and guidance provided here facilitate:

• Manage optional server-side parameters
• Check for modifier elements and extensions
• Manage optional _include and _revInclude situations
• Manage _element filtering
• Manage version differences among servers
• Provide simpler functions with typical search parameter filters (e.g. including only final and amended observations)
• Manage extension retrieval for extensions expected to be present (e.g. USCore and CRD extensions)

• Complex element retrieval such as "Cumulative Medication Duration" and "Body Surface Area"

• Authoring
• Patterns
• Libraries
  • USCoreCommon
  • USCoreElements
  • USCoreTests