#FHIR, CDS-Hooks, and Clinical Decision Support

Feb 7, 2017

This is a guest post written by Kevin Shekleton from Cerner, and first posted to the HL7 CDS email list. Reproduced here for wider availability by agreement with Kevin ——-

TL;DR: CDS Hooks will be working with the HL7 Clinical Reasoning team to make sure our approaches are complementary, and to ensure that CDS Hooks is on a path to standardization. The CDS Hooks implementation community should expect no changes to our open, community-based development process (but should expect to see increased interest and engagement from the community).

As briefly mentioned a few days ago on an earlier thread, there is some news to share from the HL7 WGM a couple weeks ago. I didn’t share this immediately at that time because frankly, I wasn’t sure as to the details yet. Rather than posting a vague post I was waiting until we had a few more discussions before communicating this out. :-)

During the WGM, I attended a joint meeting between the CDS, CQI, and FHIR-I working groups. During this meeting, one of the topics of discussion was a new project scope statement (PSS) to semantically align Clinical Reasoning to CDS Hooks. There was an acknowledgement by the HL7 working group of the support and interest CDS Hooks has within the EHR and CDS vendor communities, so ensuring Clinical Reasoning aligns (where/when possible) to CDS Hooks is beneficial to those planning to support both projects.

The CDS working group has been working on a model for clinical decision support within FHIR called Clinical Reasoning (formerly known as CDS on FHIR). I’ve fielded many questions from folks all asking the same thing: “What is the difference between Clinical Reasoning and CDS Hooks?”

At the end of the joint meeting, several of us stuck around afterwards to discuss the two projects in further detail. Specifically, we began to directly address that aforementioned question: “What is the difference between Clinical Reasoning and CDS Hooks?”. We all agreed that none of us have ever had a very clear response to that question, mainly because each of us have been focused on our respective projects and have not sat down recently to compare/contrast the specifics of our approaches and goals.

Bryn Rhodes (primary architect of Clinical Reasoning), Isaac Vetter (Epic), and I proceeded to work for the next 6 hours or so on educating each other on architecture specifics, projects goals, and design constraints of each project. In doing so, we came away with the following high level takeaways:

  • CDS Hooks is designed solely around the execution of external clinical decision support.
  • Clinical Reasoning was designed primarily around the definition, sharing, and execution of local clinical decision support. However, the project also defines capabilities for external decision support that are based on older specifications, resulting in the overlap with CDS Hooks.

Based upon our initial work that afternoon/night, we all agreed on several things:

  • Continuing our conversations was in the best interest of both projects.
  • Both projects should be complementary
  • The sweet spot of Clinical Reasoning is in the space of local CDS
  • The sweet spot of CDS Hooks is in the space of external CDS

To reflect this, we modified the aforementioned project scope statement to commit to continuing these discussions in 2017 with the goal of more directly aligning the projects. Specifically, we agreed to explore moving CDS Hooks as an independent entity within the HL7 CDS community to solve the problem of external CDS, leaving the current Clinical Reasoning project to focus on the problem of local CDS.

What does this mean to all of you who are implementing CDS Hooks?

Not much, actually. We’re not changing our focus or design. The simplicity and focus of CDS Hooks has been one of its best strengths which is evident in the broad support, interest, and ease of development within the community. We will not compromise that.

What does this mean for how the project is managed?

Again, not much. CDS Hooks will remain a consensus driven open source project using modern development practices and tooling and following its own independent release process. I think this has worked well for other projects like SMART. I am working on a more formal project governance (more on this later) that should allow us to continue operating as-is while simultaneously satisfying HL7’s requirements.

Additionally, all of the conversations and work we’re just now starting will be done in full view of the community. Any proposed changes to CDS Hooks will continue to be logged as Github Issues and discussed with those interested, we’ll still run Connectathon tracks to get implementer feedback, and we’ll continue to use this mailing list and Zulip for discussions.

How does this benefit CDS Hooks, Clinical Reasoning, and the community?

First, the entire CDS community will have a clear understanding of Clinical Reasoning and CDS Hooks as well as when it’s appropriate to use each approach.

Second, both projects are going to be strengthened by our continued joint work to align on shared needs, identify gaps, and work in complementary directions rather than potentially pulling in opposing directions.

Finally, having CDS Hooks published under HL7 will benefit organizations that are constrained to recommending or implementing HL7 standards.

I’m excited for the work we’re all going to do within the CDS standards communities and specifically, CDS Hooks. The community support around CDS Hooks has been outstanding and I’m looking forward to working towards a 1.0 releases of a CDS Hooks spec this year as well as our first production implementations.