Welcome and introductions

2

@Peter Williams

@Rob Hausam

Recording, notes & attendance.

Check questions in Zulip and SNOMED International #snomed-hl7-fhir

Previous Meetings

2

@Peter Williams

@Rob Hausam

• 2023-12-12 - SNOMED on FHIR Meeting (TS & TB)

• 2023-11-28 - SNOMED on FHIR Meeting (TS & TB)

Other Meetings

10

@Peter Williams

@Rob Hausam

Recent Events:

Future Events:

HL7 Europe : Connectathon in Athens, Greece Tuesday (16) to Thursday (18) January 2024:  https://www.hl7.eu/wgm2024/index.html

HL7 International : Virtual Event January 22 Connectathon 

Belgium January 28 Connectathon HL7 Belgium for Allergy caresets (R4). https://www.agoria.be/en, also https://www.agoria.be/en/hl7-belgium. 2024-01-09 RH Suggestion that R4 could be implemented with R5 extensions to allow compatibility with R5.  HAPI R4 + R5 compatibility implemented via MIME/Request headers.  PJ Noted breaking changes in Medication Statement, however other Medication resources are mostly backwards compatible. 

Other Regular Meetings:

HL7 Group TSMG (meeting Wed PM ET every other week) - Terminology Service Management Group (HTA Thursday AM is now a subgroup of the TSMG).   2022-05-17 RH Joint session with Vocab at last business meeting.  2022-06-14 Group has approved minimum capabilities for terminology servers.  Now looking at bigger/better HL7 Terminology Server 

New Slimline Agenda 

5

@Peter Williams 

See discussion pages for links to archived discussion:  Discussions

Snowstorm Development Question

@Peter Jordan 

Question on the future direction for Snowstorm

PWI : Potentially looking at horizontal scaling by separating out country instances on number of services.   Considering test suites eg Touchstone.   Also support for use with IG Tooling.  PJ suggests could look at Inferno (wrapper for FHIR Validator).

ALO : Snowstorm-lite would allow for quicker scaling with much reduced memory footprint, with a small number of limitations such as reduced ECL capability and restriction to single Snapshots.  See https://github.com/IHTSDO/snowstorm-lite (see Roadmap at the foot of the ReadMe.txt).  Deployment to Google "AppEngine" has been tested for horizontal scaling.  Note that snowstorm-lite only supports the FHIR API (no "native" support as per original Snowstorm) with no branch structures.

Update of the Implementation Course - Terminology Services Module

30

@Jon Zammit 

Regarding Using SNOMED CT with HL7 Standards

• "Simple Map Reference Sets" link is now dead - replace with one of the directional maps?

• Since we can do this with any maps (eg Complex/Extended), could the language in this section be made more general. 

• "Where [sctid] is a value from the table above" need not be limited to the table above, could be any map reference set SCTID.

• In Snowstorm, check how the correlation id is being translated into the 'equivalence' ICD-10 coming back as 'unmatched' due to the values in the ICD-10 map.   In the case of the historical associations, we could populate the equivalence based on the association type

• How is the CTV3 map working?  In that map the target is a SNOMED CT code.  However, might be better use of our time to remove the CTV3 map rather than get it working.  Note that NHS UK were generating CTV3 codes until 2016 (mapping until 2020) so if SI codes are out of step with UK codes, then that's dangerously misaligned.

• Do we want to include the attribute value reference sets here, as the reason  for inactivation gives an indication of which historical association is going to be used.

• Check the implicit maps returned eg https://browser.ihtsdotools.org/fhir/ConceptMap?_format=json

DK: How do we express equivalence now?  Should that be done with two complementing simple directional maps, or would we use a complex map with a correlation type of equivalence?

Alt Identifier File

15

@Peter Williams 

@Kai Kewley 

Using the Alternate Identifier File in implicit maps.

No refset is available.  Can we use the scheme id?

On non receipt of a scheme id, we discussed that all 'mapped' values could be returned?

So here for example, is the scheme &url=http://snomed.info/sct?fhir_cm=<scheme sctid> needed? It would cause issues by being looked up as a refset first, and code would have to be ready to fall back to also check scheme ids.

ML suggest we need the URL parameter to indicate that the alternate identifier file should be used.  Is there a URI for the Alternate Identifier File itself?  No.

The scheme id is more specific.  It is redundant because we already have the targetSystem URI.   Could it be used for anything else or confused with anything else if we tried to use it?  

URI suggestion:   http://snomed.info/sct?fhir_alt

This will return all scheme known in the alternate identifier map.   

So here fhir_alt follows the HL7 defined pattern as per fhir_cm

The targetSystem would need to mapped to the URI (annotation/additional relationship) which gives the URI for that scheme.  705114005 |LOINC Code System|.   The additional relationship file will need to be parsed for this metadata which is needed for the FHIR server to perform these mappings between URIs and Scheme SCTIDs.

Another Question:  the source and target imply a direction and the alt identifier file can be considered to be an equivalence (Equal in R4)

R4 (also  has Product that could be used to specify the Scheme as a return value, see https://hl7.org/fhir/R4/conceptmap.html

General discussion on work being done in EU

@Marie-Alexandra Lambot @Daniel Karlsson 

See https://build.fhir.org/ig/hl7-eu/laboratory/branches/master/index.html

https://github.com/hl7-eu/laboratory

https://confluence.hl7.org/display/HEU/Laboratory+Report+Implementation+Guide%2C+Edition+1

https://build.fhir.org/ig/hl7-eu/xpandh-hdr/

ML: https://csct.be/projects.html

https://nuva.mesvaccins.net/

2023-09-19 ML CSCT now has official "Not for Profit" status as an entity.

IG Tooling Compatibility

20

Requirements for making a Terminology Server compatible with IG Tooling

See Zulip discussion here:  https://chat.fhir.org/#narrow/stream/179202-terminology/topic/Terminology.20server.20requirements.20for.20IG.20builds.2E.2E.2E

2023-07-25

• @michael lawley is implementing the requirements in Ontoserver

• Graeme is preparing the Terminology Server registry, probably a JSON document, that would make available different terminology servers, listing the capabilities, including which code systems on each server

2023-08-22

• @michael lawley the scope has expanded, advancing on the implementation. The registry will document which terminology server meet requirements, it is a centralized resource, maintained by HL7. There is document that describes this. An implementation guide developer would use this information to choose a compatible terminology server as the backend of the IG valuesets. There is a test suite that servers can apply to demonstrate compatibility, Graeme will be the curator of the list, the submission process for a new server is under development.

2023-10-03 ML Ontoserver still a work in progress in this area.

Observables model

@michael lawley 

Question on the Observables Model - was discussed in both the MAG and the EAG.   @Yongsheng Gao currently looking at proposals and next discussion will be at all staff meeting in June.

There was an inconsistent role grouping pattern in the observables, and the question was trying to find the reason for this. This is being evaluated.

@Peter Williams There is a decision to move to the grouped pattern

@Andrew Perry looking for opportunities to contribute to the observables and LOINC modeling decisions

2023-09-19 Update:  Direction of travel here suggests moving to have all attributes in a single role group, but preparatory hierarchy movements will be required first - Evaluation Procedures moving to Observables.  Discussion expected at October MAG meeting, followed by a briefing note if no major objections raised.   AP UK have concerns about problems caused with existing counterparts between the two subhierarchies.  UK did respond to RFC last week.

2023-10-03 SI responding to briefing note feedback (including encouragement from UK to engage as a matter of priority).  Discussion expected in both MAG and EAG at October Business Meetings. Two Schools of Thought:  LOINC style single observable hierarchy (order / result) vs. procedure + observable pairs for expressing ordering and results.

Post R5 Concept Map - support for SNOMED Map features.

@michael lawley 

Concept maps and SNOMED Maps  - how to materialize as both R4 and R5.

Metadata needed:  target CodeSystem URI,  source and target ValueSets.

Do we assume that a simple map is an equivalence.

For complex maps, how are the additional fields represented?   Eg in property, dependsOn and product (these are typed).   See 5.2.3.3 Complex and Extended Map from SNOMED CT Reference Sets  

CC @Kai Kewley 

Update 2023-06-13 Now working in confluence Concept Map in R5

2023-07-11 Work being done (ML) around clarity and specification for the parameters used in implicit Concept Maps.

2023-07-25 @michael lawley and Dion had a discussion on metadata and put together a proposal of a JSON based metadata, presumably to be presented to the MAG (clarified 2023-10-03)

Expand Alliance

20

@Marie-Alexandra Lambot 

XpanDH - Expand Alliance European Project.  Interoperability in Europe, targeting providing 6 x 40 hours of medical interoperability training to 40 students to fill gaps in existing offerings.  HL7 Europe (consisting of all HL7 European country affiliates) also participating.   

2023-05-30 Submission made (SNOMED International is a co-partner).  Response expected by the end of the Summer.

2023-10-03 ML News update on course proposals expected for November.  See https://cordis.europa.eu/project/id/101095594

Language behaviour compliance in Snowstorm

10

@michael lawley 

@Kai Kewley 

BCP-47 requires a dash every 8 digits so SCTIDs need to be broken up to be compliant.

Also the "x-sctlang" is required. 

Also discussed GG's request to @Kai Kewley in the behaviour around language headers and how they interact with the displayLanguage in the HTTP GET request.

R5 changes suggested around specifying language using BCP-47 

10

@Rob Hausam 

@Daniel Karlsson 

See Tuesday meeting item #6

Changes for R5  and check on use of dialect in x form in ECL Specification Appendix C:  Appendix C - Dialect Aliases

Note that where a language reference set pulls from more than one language, the BCP-47  tag could potentially missing out the <lang> element and start directly with "x-".  Options for referring to multiple languages: could be done either with a * (see https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Accept-Language#syntax ) or with a comma separated list to indicate a priority order (although this isn't supported by the FHIR parameter (unless the server went out of it's way to allow for this), or use the accept-language header).  Use case is in the displayLanguage input parameter to a ValueSet $expand operation

2022-08-31 ML CSIRO attempting to get R5 compliant Ontoserver ready in time for HL7 Connectathon.

2022-10-04 With this page moving to terminology.hl7.org it is no longer subject to the ballot process.  Instead a "TSMG" ticket should be created.  @Daniel Karlsson and @Rob Hausam will progress this. 

Also tracking R5 changes to concept map - see http://build.fhir.org/valueset-concept-map-relationship.html.   @Peter Williams to check SI intention for R5 compliance.

2022-10-18 DK EHealth Working Group on Semantics - discussion on cross border infrastructure based on CDA.  Suggestion that it could move to FHIR for new specifications/developments eg Lab Reports.

2022-11-02 RH Rob will check the status and how we can help it move

2023-02-07 RH R5 Ballot is complete.   Deadline to complete resolutions is Feb 24th.   Expectation to publish late April / early May.

2023-03-07: RH R5 going through QA currently. Some last-minute changes in ConceptMap: RH change in relationship types, new ValueSet to remove ambiguity. Directions of maps (very) explicit. No-map situation simplification. Element name changes. Choice datatypes in more places. ML property, dependsOn and product clarification. E.g. property is used in implicit ConceptMaps based on SNOMED complex maps. http://hl7.org/fhir/5.0.0-draft-final/conceptmap.html 

2023-07-11 ML Added UP ticket - https://jira.hl7.org/browse/UP-436 (Unified Terminology Governance Project)

Language Reference Sets in FHIR

All

Mechanisms for working with Languages

Designation extension

24 August DK Added pull request to Snowstorm  here

Implementation by ML using existing fields and specifying LangRefset in displayLanguage parameter with "preferredForLanguage" code and wildcard  Eg https://r4.ontoserver.csiro.au/fhir/ValueSet/$expand?displayLanguage=*-x-sctlang-20581000-087109&_format=json&url=http://snomed.info/sct/20611000087101?fhir_vs=ecl/160303001&includeDesignations=true

Oct 5 Release of Ontoserver 6.5.0 which includes support for language reference sets as above.

Next Steps: How to promote - could we present at a Vocab call?   (1530 ET Thursdays - may clash with SI Languages call)

8 Feb 2022 DK added Designation Extension into the SNOMED on FHIR IG see http://build.fhir.org/ig/IHTSDO/snomed-ig/StructureDefinition-designation-use-context.html

MRCM in FHIR

Machine Readable Concept Model (applies to both pre and post coordinated content)

@Kai Kewley 

MRCM is needed for writing good ECL and also for writing 'good' Post coordinated expressions.

Going forward:  suggestion that PJ and RH expose both the MRCM and the capabilities of ECL 2.0 with the wider HL7 and FHIR Communities.  See slides on ECL 2.0 here.  ML more generally this is a refinement axis which is represented as two things - the attribute and the range of values that that attribute can take.

2022-11-1 ECL 2.0 can retrieve MRCM refsets content, the question is how to return them as FHIR resources (structure map?)

Using implicit concept maps may be an option to add operations such as get acceptable attributes or get range

(note SNOMED is the only CodeSystem that uses implicit concept maps, wording around that is changing, see https://jira.hl7.org/browse/FHIR-39266 )

SNOMED FHIR Implementation Guide

@Peter Williams

Implementation Guide for using SNOMED CT with FHIR.

IG Documentation: http://build.fhir.org/ig/FHIR/ig-guidance/index.html

Also look at the sample IG https://github.com/fhir/sample-ig see build http://build.fhir.org/ig/FHIR/sample-ig/

TODOS 

• Check build issues http://build.fhir.org/ig/IHTSDO/snomed-ig/qa.html    Update 2022-06-20 Tooling currently giving a null pointer, see https://build.fhir.org/ig/IHTSDO/snomed-ig/failure/build.log  asked question in Zulip  See https://chat.fhir.org/#narrow/stream/179252-IG-creation/topic/Null.20pointer.20in.20ValueSetRenderer   

• Note page to manually execute build through HL7 Tooling: https://fhir.github.io/auto-ig-builder/builds.html

• Rerun locally with latest tooling (also sushi)

• Run with local snowstorm provided as Tx

• See Mark Kramer presentation   https://www.youtube.com/watch?v=OmcSuAMf20s  Also https://fshschool.org/ 

• CONTENT! 

• Merge in DUC branch (Designation Use Context) with a view to implementing in a branch of Snowstorm and making available via connectathon.ihtsdotools.org

• Clean up other branches

• Check templates are up to date - should now be self updating, see https://github.com/FHIR/sample-ig (fsh may ask to update this structure).   Sushi sending out information about new format (PJ says leading whitespace is now significant).

• ReadMe should provide links for Publisher tooling

• Add discussion on Refset / IN (see above)

• Provide link to it in http://build.fhir.org/snomedct.html and discuss further socializing.

• TerminologyCapabilities caching is overly aggressive.

• Added 2022-08-23 Discuss ownership, hosting and copyright (joint copyright with HL7).  Source will be hosted in GitHub, pull requests will be welcome with this group acting as gatekeepers (reviewers) for that?   @Suzy Roy would the wording of our original collaboration be helpful here?

2022-11-1: No news, check in the next call.

2022-11-15  Suggestion to set page per meeting list to work through.  Setting up one or two HTML style pages that could then be copied and modified and then use meetings to tackle more difficult content and review.  Finding best publishing location, cross referenced between https://terminology.hl7.org/SNOMEDCT.html

Pairings - Kai, Peter, Marie, Daniel, Rob

Top Topics

• What are the various Resources in terms of how they relate to SNOMED CT (Link to Follow the yellow brick code presentation).  

• ECL in FHIR (intensional ValueSets being less brittle)

• Languages

• Terminology Binding (General Approaches)

• IPS (GPS)

• FAQs eg how to recover historical assertions using Map

• Post Coordination & Transformation

• Relevant changes in R5 eg Concept Map (correlation changes)

2022-11-29

Example markdown page that could be copied and modified:  https://github.com/IHTSDO/snomed-ig/blob/master/input/pagecontent/sct_specific_behaviours.md

Work to be presented for 13 December (payment will be made in Glory^tm)

Peter & Kai - ECL in FHIR  (Update:   Used https://hackmd.io/  for collaborative markdown editing. )

Daniel & Marie - Allergy & Intolerance : (Update: Menu item added for extensions, confirmed examples are useful and appropriate for the Allergy Guide. )

Rob - IPS

2022-12-13 ECL Page reviewed - MarkDown not displaying the same as it did the IDE, revisit.

Looking for some more structure that could be applied to the apparently unordered list of ValueSets (which is machine generated).  Any documentation on how to do that would be appreciated.   Other IG's we could compare to are : https://build.fhir.org/ig/HL7/US-Core/terminology.html & http://build.fhir.org/ig/HL7/fhir-ips/  ( also http://build.fhir.org/ig/HL7/fhir-ips/terminology.html )

2023-02-07 MAL work for Allergy Implementation Guide (which the SNOMED IG will link to) see SNOMED CT Clinical Implementation Guide for Allergy, Hypersensitivity and Intolerance

2023-02-21 DK Work done for languages - https://build.fhir.org/ig/danka74/snomed-ig/branches/languages/  Discussion about overloading of parameter for both display language and search language.   Checking behaviour around fall-back on displayed terms (eg context specific → national language → English).   For example, display parameter being a comma separated list (which has a defined order, unlike repeating the same parameter multiple times (also not allowed in the spec)).

2023-10-16 PWI Update:  We had a note to follow up on https://www.hl7.org/fhir/R4/valueset-animal-breeds.html as these have mostly been inactivated and moved to the Veterinary Extension.   In following up, it was determind that this valueset is no longer present in the FHIR core as of R5.

Expanding ValueSets across multiple Editions.

Discussion on * version wildcard. (relates to a Zulip discussion on expanding a ValueSet against multiple editions to give a superset?)  DK How could we specify the latest version of multiple modules.   Answer http://snomed.info/sct/*   (ie not specifying the version) or http://snomed.info/sct/*/version/*  to include concepts from previous versions.

For use in the module / version URI.   Existing workaround is to use multiple include elements for each version.

7 Sept ML Sticking point - what do we do with incompatible properties eg active/inactive between two different versions - the most recent?

Use case: primarily being able to validate codes that might exist in different editions.   Secondarily, being able to validate code received in a historical record ie where codes were valid at time of data entry.

25 Jan 2022: Snowstorm will already look across all Editions loaded when a codesystem version is not specified, eg:  https://browser.ihtsdotools.org/fhir/CodeSystem/$validate-code?coding=http://snomed.info/sct|443971000124108 only exists in the US Edition.  (See also the History proposals for ECL)

2022-05-17 ML Ontoserver supports ValueSets that draw from more than one version, so you could use that to compute the difference between one version and another.

2022-11-1: DK: Snowstorm does not yet support multiple include elements in different versions for the SNOMED code system. ML: The semantic is not yet clear, how to decide in which versions you check properties, parents, etc. Run separately for all inclusions and join the results. May need to understand better the use cases.

@Michael Chu - let's discuss.

Any Other Business

2023-10-03 ML working on registration of congenital abnormalities - is there a way to group disorders (eg as part of a syndrome), specifically in the Condition Resource to (See Condition Related Extension in R4 http://hl7.org/fhir/R4B/extension-condition-related.html / http://hl7.org/fhir/extensions/StructureDefinition-condition-related.html )   See https://hl7.org/fhir/extensions/extension-registry.html  also condition-dueto.  JC Syndrome is just a grouper name, it doesn't "cause" the manifestations as such.

SNOMED Family of Languages

@Peter Jordan

@michael lawley

Impact of proposed changes (eg text searching in ECL) on FHIR. Questions around which language reference sets to use when there are multiple, especially partial/overriding context (referred to MAG for discussion)

8 Sept The FHIR specification does not specify a particular version of ECL, so we assume the latest.  Any enhancements added to ECL will be immediately relevant and available in FHIR.   Note that these latest additions while targeting descriptions are a concept filter, so display options (language etc) will affect the output of those concepts.   How about the filter parameter though, especially since ECL wo (ld allow multiple filters in multiple/different languages.

Specify CodeSystem in FSH

@Daniel Karlsson

FSH apparently has no way of specifying the version of a CodeSystem. Daniel checking the ANTLR spec. https://github.com/FHIR/sushi/issues/473

API for FHIR Resource ↔ Post coordinated expression mapping

@Peter Williams

API for FHIR Resource to SNOMED Expression

Looking up an SCTID in an unknown module

@Peter Williams

Problems when dependencies do not align. Multiple code system resources represent multiple editions / versions.

ML: See code parameter to code system search. Should return code systems (ie versions) where that code is defined. International concepts would appear in every edition known to the server.

eg /CodeSystem?system=htp://snomed.info/sct&code=12345678&_elements=version

GPS