Explore these resources to get an overview of CQL and learn how to develop, test, and implement CQL.
- Visit the CQL Frequently Asked Questions (FAQs) page to review common questions and answers.
- Find the QDM versions for use with Clinical Quality Language (CQL) on the QDM page.
- Visit the Connect tab to find out how to connect to various CQL resources and register for upcoming CQL sessions.
CQL Tools and Resources for Implementers and Authors
| Tool/Resource | Description |
|---|---|
| CDS Connect | Clinical Decision Support (CDS) Connect is a freely available web-based platform, including an authoring tool and a repository, enabling the CDS community to identify evidence-based care, translate and codify information into an interoperable health information technology standard, and leverage tooling to promote a collaborative model of CDS development. *Note: On April 28th, 2025, AHRQ’s CDS Connect went offline. An updated, likely final version of its authoring tool has been developed by the HL7® community as CDS Connect Community Edition. A newer set of tools, the open source CQL Studio, is an integrated web application suite for developing, testing, and publication of CQL- and FHIR-based artifacts that can be developed into computable guidelines, CDS, or dQMs, providing a functional superset of capabilities. |
| Clinical Quality Framework | The Clinical Quality Framework is a joint effort by the Clinical Decision Support and Clinical Quality Information Work Groups to identify, develop, and harmonize standards that promote integration and reuse between Clinical Decision Support (CDS) and Clinical Quality Measurement (CQM). |
| CQL Formatting and Usage Wiki | The Clinical Quality Language (CQL) Formatting and Usage Wiki is a collaborative, community-driven workspace dedicated to the development and sharing of CQL formatting conventions, coding patterns, and best practices. It serves as a central resource for measure developers, health information technology (IT) implementers, and clinical informaticists to standardize how CQL logic is represented within electronic clinical quality measures (eCQMs) and other clinical decision support artifacts. The Wiki provides practical guidance on writing clear, consistent, and maintainable CQL, including examples, templates, and usage recommendations, helping ensure that quality measure logic is accurately interpreted, interoperable, and easier to implement across different health IT systems. |
| CQL GitHub Repository | This repository contains documentation, examples, and tooling in support of the CQL specification, including a CQL compiler and ELM runtime, including:
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| CQL-to-ELM Translator Reference Implementation | The CQL-to-ELM Translator is an open-source reference implementation that translates the high-level Clinical Quality Language (CQL) source into the Expression Logical Model (ELM), a machine-readable representation of CQL logic. The translator supports syntactic and semantic validation of CQL and can generate ELM in XML or JavaScript Object Notation (JSON) format. Developed as part of the Clinical Quality Framework (CQF) effort, it supports consistent implementation of CQL-based artifacts by providing a standardized intermediate representation that can be used by authoring tools, validation tools, and CQL execution engines. For more information or to get involved, visit the Clinical Quality Framework initiative page. |
| HL7 FHIR Quality Measure IG | The Quality Measure Implementation Guide (QM IG) is intended to provide guidance on the representation of quality measures including digital quality measures (dQMs) using Fast Healthcare Interoperability Resources® (FHIR®) Clinical Reasoning Module. It defines the required structure, metadata, terminology, definitions, and logic needed to author, package, and evaluate dQMs in a consistent and computable way. |
| MADiE | Measure Authoring Development Integrated Environment (MADiE) is a software tool that makes creating and testing electronic clinical quality measures (eCQMs)/digital quality measures (dQMs) easier by combining both steps in one application. MADiE allows eCQM developers to author eCQMs using Quality Improvement (QI)-Core, the Quality Data Model (QDM), and Fast Healthcare Interoperability Resources® (FHIR®) to test and verify eCQM behavior. MADiE helps eCQM developers execute eCQM logic against the constructed test cases to provide users with information to evaluate if the eCQM logic aligns with the intent of the eCQM. |
| QDM-based CQL Style Guide | The Quality Data Model (QDM)-based Clinical Quality Language (CQL) Style Guide provides standardized expressions of electronic clinical quality measure (eCQM) concepts across eCQMs and defines a uniform “look and feel” to eCQM logic. The QDM-based CQL Style Guide focuses on a set of common best practices that have been implemented across QDM-based eCQMs in CMS quality reporting programs. The QDM-based CQL Style Guide also promotes the use of consistent language within the framework of CQL, including libraries, aliases, definitions, and functions, and provides guidance on other conventions, such as operator precedence. eCQM stewards or developers who are developing or specifying eCQMs for potential inclusion in CMS reporting programs should follow these best practices. |