Open Clinical Decision Support

Tools and Resources

A consortium effort, connecting collaborators together across the healthcare continuum to improve patient outcomes through the effective use of standards-based, open source clinical decision support.


OpenCDS is a multi-institutional, collaborative effort to develop open-source, standards-based clinical decision support (CDS) tools and resources that can be widely adopted to enable CDS at scale. OpenCDS software is licensed under the Apache 2 license.

The project supports a Java-based engine and tools providing standards-based support for Clinical Decision Support software

OpenCDS was initially envisioned in 2010 by Dr. Kensaku Kawamoto, as a generic design to apply lessons learned in the use of an earlier CDS system he had developed. His approach is to create software that will:

  • transform proprietary source data from the EHR into a standard data structure
  • evaluate the data using a set of rules based on the latest researched medical knowledge, and
  • return appropriate treatment suggestions for an individual patient.

While the above items sound simple, there are many complexities in practice, and the software has grown to a substantial level of maturity, with capability for a variety of use cases and operating environments.

OpenCDS features support for HL7 standards, but can be customized for any desired API and data standards.

OpenCDS clients currently have the following options to communicate with the software: Rules may be written in any of the following:
  • Java
  • Drools
  • HL7 CQL (future support)
  • any existing or custom rules language (requires development of an adapter)

If you would like to access the software and documentation, please Join the Community.

If you have further questions about OpenCDS, please Contact Us.

2022-09-30 By: Phillip Warner

Registration No Longer Required

Greetings. We are pleased to announce that OpenCDS no longer requires registration. The OpenCDS Bitbucket (Git) repository, Documentation (Confluence) and Issue Tracker (Jira) are now generally available.

Please see the Resources page for details.

As always, please feel free to ask questions in the opencds-users or the opencds-dev Google Groups, or you can also Contact Us.