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Formatting and Usage Topics

Bryn Rhodes edited this page Jan 8, 2019 · 8 revisions

Wiki Index


Authoring Measures in CQL

Composite Measure Development

Cooking with CQL Examples

Cooking with CQL Q&A All Categories
Additional Q&A Examples

CQL 1.3 Impact Guidance

CQL Error Messages

Developers Introduction to CQL

Discussion Items

Example Measures

Formatting and Usage Topics

Formatting Conventions

Library Versioning

Negation in QDM

QDM Known Issues

Specific Occurrences

Specifying Population Criteria

Supplemental Data Elements

Terminology in CQL

Translator Options For Measure Development

Unions in CQL

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Formatting and Usage Topics

The Clinical Quality Language Specification (CQL) defines a high-level authoring language designed to be usable by clinical domain experts to express the reasoning aspects of clinical quality artifacts in the quality measurement and decision support domains. The language is a general purpose query language extended with specific functionality to support constructs and functionality common in these domains.

Because of the flexibility and broad applicability of CQL, it necessarily covers a breadth of topics. This guide provides recommendations and guidance to ensure consistent and appropriate use of CQL, especially in the context of expressing clinical quality measures using Quality Data Model (QDM) to represent patient information.

In addition, several of the topics in this guide discuss issues related to the use of CQL within Health Quality Measures Format (HQMF) to represent electronic Clinical Quality Measures (eCQMs).


  1. Formatting Conventions
  2. QDM-Related Formatting Conventions
  3. Terminology in CQL
  4. Negation in QDM
  5. Specifying Population Criteria
  6. Supplemental Data Elements
  7. Composite Measure Development
  8. Library Versioning
  9. Authoring Measures in CQL
  10. Representing QDM Specific Occurrences
  11. Unions in CQL
  12. CQL Error Messages
  13. CQL 1.3 Impact Guidance