Convergence: CEDD, CIMI, IHE, FHIR, hData, HL7, mHealh and ONC

@motorcycle_guy @Fridsma RE "How do all the (CEDD, CIMI etc) models fit together?" < looking 4 an answer - do we have 1 yet? #siframework
— Thomas Lukasik (@Sparkenstein) June 8, 2012

How does it all fit together? If you've been following CIMI, HL7's CDA Release 3, FHIR, and mHealth Workgroup initiative, ONC's many S&I Framework projects, IHE's mHealth profile and all the other standards activity going on, surely you've run into the problem shown below:

The volume of the information stream coming out of these projects is huge.  Keeping up with all of these projects requires a staff and budget that is much bigger than I have available to me, so I haven't been to all of the meetings, attended all of the calls, or paid attention to all that is going on. But I have managed to understand enough about what is going on to sort of figure out how some of it COULD fit together.

Content
Knowing the history behind things helps.  The S&I Framework CEDD is based in part on the HITSP C154 Data Elements, with a slightly different twist.  That set of data elements comes from various CDA  documents created by HITSP and based on HL7 CCD, and IHE PCC profiles.  Coming out of that same body of work is the CDA Consolidation Guide.  And a good bit of it hearkens back to the HL7 Claims Attachments.

The CIMI work is informed by work in HL7 on Detailed Clinical Models, as well as work in ISO, and in OpenEHR.  Those communities have cross-pollinated pretty well, although you'll find some observers indicate otherwise.  A lot of the CIMI work will, I expect, also be informed by the Intermountain Clinical Element Models, which show a marked influence from CCD and HL7 Patient Care Models.

FHIR will be creating resources for many of the very things that CIMI will be creating "detailed clinical models" for.  What FHIR doesn't cover directly can be covered by it's built-in extension mechanism.  And unlike CIMI and an attention to all the detail, FHIR will only be addressing the most commonly needed or implemented data elements.

Documents
On the CDA Release 3 front, Structured Documents has moved away from defining clinical content, in deference to allowing clinically related workgroups in HL7 to use their own models in RIM-based healthcare statements.  They are also moving towards XHTML in content, something which FHIR has already adopted.  An FHIR has a resource aggregation model that supports documents as well as messages and services.  The actual XML for CDA Release 3 is defined by the HL7 XML ITS, but it could be readily transformed to the FHIR format if the R3 Document was sufficiently well-defined.  I expect the most significant efforts of Structured Documents as related to FHIR will be on defining the "document" resource.

Transport
On the transport side, we have the IHE mHealth Profile based in part on, and being harmonized with hData.  This profile builds on the IHE XDS Metadata which is presently part of Direct and Exchange.  ONC's RHEx Project also seems to be building from hData.  And finally, FHIR has a RESTful protocol which is also being harmonized with hData.

Fitting it all Together
So we have three streams in which convergence could occur.  On the content side, is how we model clinical information.  CIMI and OpenEHR are building models for that that go into great detail, probably much more detail than many systems know how to deal with today.  This can readily fit into FHIR over time, and is largely compatible with CDA Consolidation efforts given the great deal of cross pollination and common ancestry that has appeared.  I see CDA Consolidation templates being dominant in the near and mid-range future, with movement towards FHIR Resources over the mid- to long-term.

On the document side, it isn't clear whether CDA or FHIR will win out.  I suspect that FHIR will become dominant in the messaging and service space first, before eclipsing CDA in the longer term.

Finally, the RESTful transport will become some variant of hData, with the document model possibly evolving from the IHE mHealth profile and XDS Metadata (being restated a bit more RESTfully).

It's a way it COULD happen.  Your mileage may vary.  However, if we do manage to converge these streams, it could be very powerful.

Clinical Information Modelling Initiative

There's been a lot of discussion about the Clinical Information Modeling Initiative (CIMI) on the web recently.  You can find several posts from Heather Leslie (@omowizard) on CIMI at her blog site.  Wes Rishel (@wrishel) also wrote about an announcement the group made recently (as did Heather), and offers some advice to HL7.  Sam Heard, chair of openEHR also writes about it recently from the openEHR perspective.  It has also come up on the last couple of HIT Standards Committee meetings, and John Halamka has talked about it a couple of times on his blog in November and December.

I've heard CIMI mentioned by some as the "HL7 buster", by others as being extremely "disruptive" to the existing SDO structures.  Others are afraid that CIMI could replace all of the work that has been done (especially in the US) with CCD and CDA Consolidation, and that it would "completely revamp" Meaningful Use.  I don't think any of those outcomes will happen.  My reasons have to do with what CIMI is doing, and the way that HL7 is structured.  Before I get into that, let's take a look at some of the history.

HL7 and openEHR have been dancing around each other for years.  The two organizations are in many ways competitors for mindshare in the Healthcare Standards space.  Some of their standards overlap, but in other places they are quite complementary.  In fact, during the development of CDA Release 2.0, there was a great deal of harmonization between the HL7 RIM and the openEHR models so that CDA Release 2.0 could be treated as an openEHR "EHR Extract".


Members of HL7, openEHR and ISO have all been working on something called detailed clinical models (in HL7/ISO parlance, in openEHR, you'd call it an archetype) for the past few years (or longer in the openEHR case).  Some folks (like Heather and Hugh Leslie) have been participating across any and all organizations where this work occurs, while others have been tightly focused within smaller circles.  A detailed clinical model addresses, in some ways like a LOINC panel, the information needed to model clinical concepts in all their glory.

DCMs address (in detail), all the information needed to capture something like a blood pressure measurement, as Wes references in his post.  The level of detail can be variable in implementation, but not in the model design.  The model can get to the type of device used to make the measurement, the position of the patient, et cetera. This is the level of detail that is needed to move the interoperability needle forward past the first big chunk, and is also necessary to advance the science of medicine.  I like to think about the model of a problem or allergy, rather than the model for a blood pressure.  In allergies, you have the notion of the allergy, the allergen, reactions, severity of the reaction, incidents of manifestation, et cetera.  All of this is representable today in an HL7 RIM-based model, but what is missing globally is a formal, clinically validated, detailed model of the information, and that is what CIMI hopes to provide.

Large organizations like HL7 which have been established in a particular field, often get "stuck" in a particular kind of thinking, which is hard to break away from.  If you've read any Clayton Christiansen's books on Innovation (Innovator's Dilemma, or Innovator's Prescription), you probably can understand a few good reasons why.  Shortly after I started as an HL7 Board member, the board created the "Fresh Look Task Force", and appointed Stan Huff as chair.  The function of the Fresh Look task force was to see how HL7 could partner with, and foster innovation from outside the HL7 working group.

At the HL7 Australia Working group meeting, the dance between HL7 and openEHR moved into a new stage, no longer just exhibitionary and competetive, but more like a cautious courting stage.  There was a great deal of discussion going on in the Care Provision work group meetings about detailed clinical models.  Stan presented the idea of CIMI to the Fresh Look task force at the HL7 January meeting.  It was agreed by the task force that while CIMI was a good idea, it probably needed to occur outside of HL7 circles, and Stan and others present at that January meeting took it to the next stage with CIMI.

I have to laugh a little at Wes Rishel's advice to HL7, because of the history that I just mentioned.  It's actually pretty good advice for individual members, but as far as the organization goes, it's sort of like telling a mother not to hold back her child (BTW: HL7 is just one of many organizations that can claim some level of intellectual parentage here).  I expect that HL7 will embrace the efforts, especially when you consider the number of HL7 members already engaged.


I haven't been one of the International experts participating in the CIMI efforts for the same reason that I haven't been participating in the DCM discussions in HL7.

1. The work is more clinical that technical, and I'm not a clinician.
2. The modeling that they are doing is compatible with (and can be layered above) existing information models (including the RIM) that I'm already familiar with.

Recently, the HL7 board began deliberation about how it might make HL7 domain analysis models available to the CIMI group, so that it could take advantage of existing work.  The outgoing chair, Bob Dolin, is very supportive of these activities, and raised this issue for consideration on the last board call.

I don't think HL7 has anything to fear about CIMI.  Nor do I believe that the outputs of CIMI will render the existing work in HL7, or already in Meaningful Use Stage 1 obsolete.  Instead, CIMI will advance the industry forward a big step.  There will be a need to coordinate and "harmonize" between the CIMI models and HL7 standards, like CDA.  For that, I expect other approaches, such as the one I espoused for CDA R3 using HTML + Microdata, would enable HL7 to harmonize quite readily with CIMI.

My one and only concern about CIMI is that the extensive modeling that has already been done by IHE on perinatal care be considered.  I don't have the bandwidth (or clinical expertise as I mentioned previously) to take that on, but I do hope that some of my IHE colleagues do.

   Keith