Common CQL Artifacts for FHIR (US-Based), published by HL7 International / Clinical Decision Support. This guide is not an authorized publication; it is the continuous build for version 1.0.0-ballot built by the FHIR (HL7® FHIR® Standard) CI Build. This version is based on the current content of https://github.com/HL7/us-cql-ig/ and changes regularly. 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