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Standards Harmonization

Clinical Decision Support (CDS) & Electronic Clinical Quality Measures (eCQMs)

Clinical Decision Support (CDS) and electronic clinical quality measures (eCQMs) are closely related. They share many common data elements, terminology, technical specifications, and requirements, all of which support health care quality improvement. It is important to also understand the differences between them and the efforts to help them work together (harmonization). Initially developed separately, the standards for the electronic representation of CDS and eCQMs used different data models and computable expression languages. The use of different standards

  • makes re-using or sharing machine readable logic between eCQMs and CDS specifications very difficult
  • creates a burden for health information technology (IT) developers and those who provide technical support for implementation

Beginning with eCQMs specified for use in 2019, Health Level Seven International® (HL7®) Clinical Quality Language (CQL) replaced the Quality Data Model (QDM) as the eCQM expression language. CQL is an authoring language standard that provides the ability to express clinical logic that is both human-readable and machine-readable via a structured representation. Since CDS also uses CQL, this improves harmonization between CDS and eCQMs.

Clinical Quality Framework (CQF) Initiative

The CQF Initiative is an HL7 project led by the CDS and Clinical Quality Information work groups to identify, develop, and harmonize standards that promote integration and reuse of technical specifications between CDS and eCQMs.

Harmonization of CDS and eCQM standards improves the ease of implementation and makes it easier to integrate and facilitate health IT-enabled clinical quality improvement since the functions of CDS and eCQMs are complementary.  Fast Healthcare Interoperability Resources® (FHIR®), and CQL (both HL7 standards) provide a common foundation for representing CDS and eCQMs to

  • suggest care to clinicians and care teams when there are opportunities to improve care quality
  • assist with clinical workflow by gathering pertinent information before and during encounters for medication management,  pre-certification, etc. 
  • measure if appropriate care was provided

The HL7 FHIR specification is a standard for exchanging health care information electronically. The CQF Initiative has developed various FHIR resources, profiles, and implementation guidance to represent quality measures and decision support artifacts. These resources are

  • consistent with the Common Metadata Standard, and can use CQL to represent expression logic and the Quality Improvement (QI)-Core Framework profiles to represent clinical information
  • defined and introduced as part of the Clinical Reasoning Module of the Standard for Trial Use (STU) of the FHIR standard 
  • used and tested in a variety of settings, including FHIR Connectathons and ongoing pilots, to validate that these resources can effectively fulfill the need for a single set of standards to support delivery of both decision support and quality measurement artifacts

For more information about use of FHIR in quality measurement, read the informative whitepaper, HL7 FHIR® Guidance: Quality Reporting, Release 1- US Realm.

To learn more about FHIR, please visit FHIR pages.

To learn more about CQL, please visit CQL pages.

To participate in the Quality Data Implementation User Group, please visit here.

Common Shared and Differing Standards Between CDS and eCQMs

The table outlines the common areas and differing standards currently used in CDS and eCQMs.

 Patient and Clinical DataComputable Expression LogicMetadata and StructureEvaluation Model
CDSQuality Improvement (QI)-Core (for FHIR-based CDS)CQL

FHIR Clinical Reasoning

FHIR Clinical Guidelines

CDS Hooks (for FHIR-based CDS)
eCQMQDMCQLHealth Quality Measure FormatQuality Reporting Document Architecture

Common Shared Standards

The figure shows eCQM-specific standards and CDS-specific standards coming together with common standards.

Common Shared Standards

The strategy employed by the CQF Initiative is to identify the common components used by each domain and define common standards for each of the core components. Check the HL7 FHIR website for the most current versions.  

QI-Core is a US Realm Implementation Guide (IG) of the FHIR Specification that defines a uniform way for quality measurement and clinical decision support knowledge to refer to clinical data. The profiles align as much as possible with the Data Access Framework and incorporate content from the QDM and the Virtual Medical Record specifications.

The QI-Core IG defines a set of FHIR profiles with extensions and bindings needed to create interoperable, quality-focused applications. The profiles in this IG derive from and extend the US Core profiles to provide a common foundation for building, sharing, and evaluating knowledge artifacts across quality improvement efforts in the US Realm.

The HL7 Clinical Quality Information Work Group manages changes to HL7 FHIR IG and incorporates as part of the standard balloting process. Changes to the HL7 FHIR IG follow the base FHIR roadmap and the US Core IG roadmap.

CDS Hooks is an HL7-published specification for clinical decision support. This specification describes a hook-based pattern for invoking decision support from within a clinician's workflow. The application programming interface supports synchronous, workflow-triggered CDS calls returning information and suggestions and launching a user-facing SMART app when CDS requires additional interaction.

Last Updated: Oct 31, 2023