Welcome and introductions

2

@Peter Williams

@Rob Hausam

Recording, notes & attendance.

Previous Meetings

5

@Peter Williams

2021-10-19 - SNOMED on FHIR Meeting (TS & TB)

Other Meetings

5

@Peter Williams

Recent events:

Upcoming events:

PJ 24 Aug  No Nov Dev Days 2021.   Next will be US Edition in June 2022 (Cleveland)

Oct 5: HL7 Jan 2022 Virtual meeting: Aim for testing ConceptMap on the Connectathon (Jan 10-12). Set up an independent Connectathon after the Jan meeting?  HL7 May 2022 Dallas   

India Connectathon - Dec 10-12 https://connectathon2021.in/

HL7 Australian/NZ FHIR Connectathon Nov 23-24 https://www.eventbrite.com.au/e/inaugural-hl7-fhir-trans-tasman-connectathon-registration-193185943357 IPS, SMART Health Cards, Provider Service Directories, SMART on FHIR

New HL7 Group TSMG - Terminology Service Management Group (relationship with HTA still being defined)

Upcoming R5 changes

10

@Rob Hausam

Discussion about proposed federation.  ML Doesn't work so well with SNOMED CT because there's not a single authoritative source due to country extensions (and multiple versions being released).  Use case for this is mainly in creation of IGs.  Agreement that what a conformant server should be able to state in Capability Statement is helpful.   ML Touchstone test script artefacts need investment.  See https://touchstone.aegis.net/touchstone/

See also https://inferno.healthit.gov/

HL7 / SNOMED Collaboration

10

@Suzy Roy

@Rob Hausam

https://www.snomed.org/news-and-events/articles/HL7-SNOMED-partnership-renewed-agreement-(1)

Includes continued support for this group for TS + TB,   FHIR SNOMED IG also mentioned and potential for engagement at HL7 events.  IPS + GPS.

FHIR Implementation Security Issues

10

@Peter Jordan (Unlicensed)

HL7 Responded via email to https://approov.io/for/playing-with-fhir/

https://www.hl7.org/documentcenter/public/newsroom/HL7%20Statement%20on%20Playing%20with%20FHIR%20Paper.pdf

MLDS send out updates for IPS, feedback received

10

@Daniel Karlsson (Unlicensed)

Potential for confusion between International Patient Set vs International Patient Summary

SR: SI calling this the "IPS Set" - check documentation with @Andrew Atkinson

Update: Andrew agreed this should be "International Patient Summary (IPS) Refset" throughout.

VCI Group questions:

10

@Rob Hausam

@Suzy Roy

VCI (Vaccine Certificate Initiative) Group questions:

• Can all the vaccine related codes (inc Extensions) be released via GPS-like licence?   SR Answer a lot of code were included in the GPS by virtue of being part of the IPS over and above COVID related to the original WHO Vaccine Certificate Initiative.   Discussed that product specific codes (eg with Brand names) would be country specific and the GPS works at the International Level

• Can a list of all the codes in :one: be released in a single place (to avoid implementers having to check different national editions)?

• What’s the process for getting new vaccine codes if needed in the int’l edition? What’s the timeline for release under a GPS-like license?

DK Discussion about different brand names in different countries (which have different codes) and whether they can be considered the same thing.  Becomes political issue.

Support for Post Coordinated Expressions

10

Heiko Waldmuller

@Peter Williams

"Using postcoordinated codes over an information model that the syntax fits the MRCM."   Question on how to post-coordinate medication plan type concepts into PCE

PWI - Well FHIR is pretty clear on this question in that - as far as the specification is concerned:  a post coordinated SNOMED code IS a SNOMED code, so they can be used interchangeably.  The syntax is well documented - SNOMED Compositional Grammar http://snomed.org/scg   What the MRCM does is tell you what attribute types can be used in a given domain (ie subhierarchy) and what attribute values can be used with each attribute type.   The constraints of the MRCM are really outside of the concerns of FHIR, but we can certainly talk around that topic this evening.   We do not have a way to express the MRCM in FHIR....that's perhaps something we could look at.

ML - recommended using existing resources or extending http://build.fhir.org/basic.html

PJ - suggested looking at http://build.fhir.org/allergyintolerance.html

DK - See also work done by this group of profiling allergy intolerance - AllergyIntolerance Binding

Please report back Heiko!

Use of SNOMED attribute concepts in FHIR Resources

15

@Elze de Groot

@Feikje Hielkema (Unlicensed)

"In the Netherlands we are struggling with the conversion of SNOMED in information models to FHIR. It seems that not all SNOMED concepts of attributes in information models can be used in the FHIR model. One example is attribute concepts in SNOMED. In an information model/dataset we (terminologists) use SNOMED attributes in combination with the context it is used in. For example in the clinical building block ‘problem’ we use as root concept ‘ Finding with explicit context’ and we use for the verification status the attribute ‘408729009|Finding context| so we can make a post coordination from the clinical building block when needed.   Another example is the clinical building block ‘drug use’. The root concept here is 228366006 | Finding relating to drug misuse behavior| and for ‘DrugOrMedicationType’ we use the attribute ‘47429007 |Associated with (attribute)|’ conform the concept model of SNOMED.

But, if we do this, this is not conform the FHIR model, because a SNOMED attribute is impossible to use in a ‘component’ of the FHIR model (according to our FHIR experts). I don’t know much about FHIR yet. That’s why I might joint the FHIR group to learn more about the SNOMED to FHIR issues that exist.  My question is, is this issue already seen/recognized before in the SNOMED on FHIR group and if yes is there a solution for it? Is there a way to find out how others dealt with it?"

Question is on converting an information model instance to become a Post Coordinated Expression.

ML - would use PC as a last resort.

DK suggested Binding patterns  ( see also here ).   Discussed mapping a SNOMED Template to the fields in a FHIR Resource.

AP - UK use just the medication itself in AllergyIntolerance if a pre-coordinated concept (allergy to X) is not available.

Update 2 Nov Implementation Support Team met with Elze's team. Observations about illicit drug use using FHIR "component" element to indicate which drug is involved.  RH offered to assist.

TRAG work item - Module Composition 

5

@Peter Williams

@michael lawley

http://build.fhir.org/terminologycapabilities.html   ( https://browser.ihtsdotools.org/fhir/metadata?mode=terminology  cf   https://r4.ontoserver.csiro.au/fhir/metadata?mode=terminology&_format=json  )

http://build.fhir.org/capabilitystatement.html

ML - this is a question about packaging rather than modules.  We can currently refer to versions of a CodeSystem which links back to the Module Dependency Reference Set.  Terminology Servers get populated with more than one release package (eg GPS).   Maps sit outside of the versioning mechanism (accessed implicitly with SNOMED).

May be scope for addition to TerminologyCapabilities resource.

IPS Terms

10

@Peter Jordan (Unlicensed)

IPS Terms - cross border use case, matching terms to context of use.

RH - general discouragement of using FSN for display.  PJ - Gets better results with ValueSet $validate when using FSNs

PWI could validate-code check all translations on the server  ML - $validate-code should be language sensitive

PWI - We should look up the displayLanguage and see if we've an extension installed that uses that language.

New change proposals for $validate-code

10

@Peter Jordan (Unlicensed)

G Grieve have created new HL7 Jira tickets: https://chat.fhir.org/#narrow/stream/179202-terminology/topic/Change.20Proposals.20for.20.24validate-code.20post.20Connectathon

Grahame Grieve: https://jira.hl7.org/browse/FHIR-33941: $validate-code should return system | version | code when display is returned

Grahame Grieve: https://jira.hl7.org/browse/FHIR-33943: $validate-code should return an operation outcome with the full details of issues found, including paths

Grahame Grieve: https://jira.hl7.org/browse/FHIR-33944: $validate-code and $expand should have a parameter for related value sets and code systems

Grahame Grieve: https://jira.hl7.org/browse/FHIR-33946: $validate-code and $expand need a session parameter (as optimisation where ValueSet may need to be uploaded for a series of calls)

Grahame Grieve: https://jira.hl7.org/browse/FHIR-33947: Clarify the use of fragment  (this is a discovered issue from the same session, relating to the first of the tasks above)

ML - general principle that services should echo back the details they've been sent to process.

PJ - CodeableConcept (with multiple codings) will require multiple responses.  ML - call multiple times with single codes as a workaround.

What is a Fragment (in a SNOMED use case) ?

@michael lawley

Incomplete CodeSystem Resource.

UCUM effectively infinite, but a finite set is used in practice so we can capture that as a fragment.

What does in mean & what do we do when we have overlapping fragments?   Similar problems exist with CodeSystem eg valid codes aren't present due to what's been loaded on a particular servers.

Review proposed changes to URI Specification to support unpublished content

@Peter Williams

2 SNOMED CT URI Space

Sorry link not visible externally until published. we'll have to screen share to view it.

7 Sept Group reviewed, no concerns expressed.

Inactive concepts in the FHIR Spec

10

@Former user (Deleted)

Laterality Reference Set documentation contains inactive conceptsFHIR-32889    ValueSet is status Draft.  Sits with the Order and Observation Workgroup.

https://github.com/mertenssander/fhirSpec_sctid_scraper

Notes:  ML Suggested giving the historical associations for these concepts.

PWI Noted:   Could you check 162023004 |No problem swallowing (situation)| ?   It looks active here:  http://snomed.info/id/162023004   Update - sheet needed filtered on "true" to indicate inactive.

RH Appreciated you doing this work @Former user (Deleted) and AP appreciated having a python example to play with!

Next Steps:   Once we've confidence in the results, RH to advise on the different HL7 Groups to contact with the various sections with a view to targeting R5 ie by September (in time for January ballot)

27/07/2021:- RH not had a chance yet. Vocabulary HL7 workgroup may be interested. Rob will also bring to Orders & Observation workgroup.

We can try our best to update what is in the specification, or propose a more useful definition that HL7 can adopt.

ML There is a flag on ValueSets showing whether inactive codes are allowed in an expansion, i.e. perfectly fine depending on use case of ValueSet. 

RH keeping terminology in specification can be painful. There's a tracker for moving forward with this. Potentially moving to terminology repository rather than a specification.

7 Sept RH to bring up at Vocab working group week of 24th.

5 Oct Which FHIR build? Ask @Former user (Deleted) to either post a ticket on HL7 Jira or send results of scraper to @Rob Hausam

AND / OR  in ValueSet Filter

@Peter Williams

Normally when a filter is applied eg "Size 12" + "green" we expect both qualities to be true at the same time and this is held true by the FHIR Spec that says "If multiple filters are specified, they SHALL all be true."  (see http://build.fhir.org/valueset-definitions.html#ValueSet.compose.include.filter)  However  http://hl7.org/fhir/R4/valueset-substance-code.json.html  has two filters that pick up substances PLUS products   and obviously they can't both be true at the same time.    So it seems like sometimes we use conjunction and sometimes disjunction?  

Snowstorm GitHub issue #285 changes behaviour from AND to OR when multiple filters are applied.

Answer is: the separate includes are disjunctive and objects within the same filter array are conjunctive.

Text here is clearer: http://build.fhir.org/valueset.html#compositions

SideNote:   Wildcard for versions in $expand, see https://jira.hl7.org/browse/FHIR-15998   Note that "version" here would mean multiple editions.

Update on Frequent Releases

@Peter Williams

Done.

PCE implications for FHIR Operations

@Peter Jordan (Unlicensed)

@michael lawley

$validate-code, obviously.   ML  Transformations of Close to User Form happen under the hood of the TS.   You might want to see normalized form, although it will be dependent on the particular edition in use.    Current Snowstorm development is WIP / experimental rather than a ratified spec.   Order of transformation is important + existing issues with negation in hierarchy subsuming in unwanted ways.   PJ Essential to have first pass attempt to bottom out issues, highly beneficial. 

$subsumes

What about ValueSet $expand - return Normalized form or original input?   Classification will be needed before membership of ValueSets can be determined.

$find-matches could be used to find / check PCEs / Normalized equivalencies.   Alternatively, deprecate this operation altogether!

$translate could return normalized forms of CTUF.  ML Syntactic differentiator needed?

Update 13 July@Former user (Deleted)has completed a multilingual tool for creating concepts based on template:   https://postco.test-nictiz.nl/#/     (source:  https://github.com/mertenssander/postco) 

TODO @Peter WilliamsCopy text out and archive.

Definition of GPS

@Rob Hausam

Request that SI make the GPS ValueSet available as an extensional definition.

SI are (I think - PWI) in agreement to do this.

Refset / IN documentation clarification

@Former user (Deleted)

Note conflict with http://build.fhir.org/snomedct.html#4.3.1.0.8.2 the filter "Reference Set" causes confusion with the "In" operator being a list of codes in other CodeSystems but when used with SNOMED we expect a single Refset concepts which is then evaluated for the active members of that refset.

15 June 2021 ML With other concepts, "IN" means a comma separated list of which the concept we want is one of those.   ValueSet is Normative and this has been the state of play since way back.   DK Would be impossible to change without breaking backwards compatibility.   PJ Could we suggest using ECL instead (as advice) to avoid ambiguity?  ML is a bit redundant since a VS could be defined with a set of codes in compose.   PW Can we highlight that SNOMED is different in this area?   See http://build.fhir.org/valueset-filter-operator.html (actually in the CodeSystem that defines the filter operators) also https://www.hl7.org/fhir/valueset-filter-operator.html#expansion.  DK There are servers that implement "IN" but not ECL eg GG's (RH thinks HAPI does the same).    The current situation of two different behaviours is problematic.

Suggest that SNOMED servers specifically reject the use of  IN when presented with comma separated list of concepts which is disallowed in 4.3.1.0.8.2 AND that it has to be a refset id.   Note that the definition for "=" is also different for SNOMED when we use ECL rather than some property of the Concept ("The specified property of the code equals the provided value.")

TODO Write up options in the IG and see if further/wider conversation develops.   Is there a tracker for this @Former user (Deleted)?  

Update 13 July - See discussion in comments below.

Topics for Terminology Binding Stream

5

@Daniel Karlsson (Unlicensed)

@Jeremy Rogers (Unlicensed)

Collecting topics for TB stream here, with a view to having a call when there's sufficient material

FamilyMemberHistory - how is "no family history of X" best represented?

FreshDesk ticket question on Allergy substance cross field validation.  DK: Mappings to other information models, is that helpful?

15 Dec 2020 DK Asking if the member forum are still keen to see engagement in this area - offer to help country implementations.   Difficult to make decisions on binding without a concrete use case.  ML We could look at / review IGs (DK As we did for COVID).

12 Jan 2021 Update: Contact planned with the MF - next call (Jan 22) is topic based, so after that one - 2 Feb (with Daniel)

9 Feb 2021 Update: Briefing note (DK) ready to be presented to MF.   Now (23 Feb) submitted for discussion, waiting for date in March or April.

9 March 2021 Update: Daniel to present to MF on 11 March (Thursday!)

23 March Update:  Presentation given, awaiting feedback.   Reminder @Suzy Roy?

06 April Update: SR There's a follow up in April business meeting (member forum meeting) for feedback. DK reading through/presenting resources may not have been the best approach; maybe presenting use cases would be better. PJ agrees as its more relatable. 

20 April:   Topic for discussion - new Resources introduced in R4B.    Also (Linn Brandt) Use case: Registries need nullFlavor-concepts in their value sets. Which code system to use?  Consider "Long COVID no longer present" as a topical example.  4 May DK: This is more of a negation issue than null flavour, also probability.   JL Distinction between unknown and uncertain.

4 May Jay Lyle - FHIR Binding, proposal review in Observations and presence of findings eg for more of an examination based context. 

1 June @Peter Williams to check in with JL.  Done, said nothing further for this group at this time.

Oct 5 Request for input from nutrition CRG.

R5 Position

5

@Rob Hausam

ML ConceptMap moving from R4 to R5.

9 March 2021: Last updates coming in, delayed due to tooling issues.   Balloting open in next few days.

06 April 2021: RH R4B went to ballot couple weeks ago.   http://hl7.org/fhir/2021Mar/ballot-intro.html   "R4B planned for late Q2 or sometime in Q3, 2021"

20 April 2021 : R5 Balloting has commenced (using Jira for the first time) until May 17. 

1 June Next Ballot Jan 2022

Update 13 July ML queried missing changes from ConceptMap.  RH says still progressing.

Update 27 July Next biggest batch to complete is ConceptMap for R5. Dependant on a terminology server supporting the changes on R5. May not be testable in September. 

Publishing SNOMED codes in IGs and licencing conditions.

1

@michael lawley

Licensing issues for IGs referring to SNOMED codes. Is this written down anywhere with some sort of rigour?

Consider the licence statement that is presented when accessing the browser. Should something similar be mandated for inclusion in any document published? What if a patient's medical record were to be published?

Update 12 Jan - "One Page Policy" to be discussed internally.   HL7 agreement indicates other parties would require affiliate licence unless they restricted their usage to the Global Patient Set.

26 Jan Question from PJ about inclusion of COVID Vaccine concepts in the GPS (advised that it is only released yearly)  FYI @Rory Davidson See also MF discussion here.  SuzyR will follow up.  See also early preview page.

06 April: SR covid vaccines have been/will be incorporated into July release. They will be in GPS when ready. 

Description Ids

1

@michael lawley

UK store description ids for historical reasons (eg Read codes using non-synonymous descriptions so must be captured and retained.  Maps are description to description) and have 3 use cases to support.    

1. Find concept id from description id (could pass description id as filter but issue of prefix matching eg 12345010 vs 123450102010)  Best Idea:  Pass a coding with the description extension element populated but NOT the code itself.  Note will require an HTTP POST call.

2. From concept get description ids of designations

3. Maps using description ids (again pass in coding with extension but not code).

The main point here is that description ids are not codes and should never appear in a code type field.   Tracker raised to allow IDs to be included in maps as "product / depends on"

UK have an extension for description Ids (and FHIR have a standard extension for same): 

The FHIR extension allows the addition of an description id to a Coding:  https://hl7.org/fhir/extension-coding-sctdescid.html  ML would prefer being able to add the id to a designation (which would meet use case 2)

27/07/2021:- ML has logged ticket for broadening scope of extension. Ticket: https://jira.hl7.org/browse/FHIR-33058 

Language Reference Sets in FHIR

2

All

Mechanisms for working with Languages

Designation extension

Update 19 May: Suggestion that we work an example for SNOMED to discuss with Regenstrief (LOINC)

Update 2 June: Started worked example Designation Extension Example

Update 17 Nov:  Proposal to add more values into designation use https://jira.hl7.org/browse/UP-107

Update 1 Dec: Latest build: http://build.fhir.org/ig/IHTSDO/snomed-ig/branches/duc/StructureDefinition-designation-use-context.html   Ticket: https://jira.hl7.org/browse/UP-155 being replaced by https://jira.hl7.org/browse/FHIR-29821   ML suggested we need an additional value for 'Not Acceptable' that would need an additional value to be explicit, rather than relying on the absence of a 'row'.   Designation Use codeset, or the infrastructure codesystem?  See also http://build.fhir.org/languages.html##term

Update 15 Dec:  Discussing cardinality - when a designation can be applied to multiple roles, do we have repeated elements in a single extension block, or multiple extension blocks?  PJ Checking use case.    Use Case:  To allow tell the client what all use contexts (roles) are available so that it can a) select one making an informed choice and b) gradual degradation where the best available terms are used where they exist, falling back to a less preferable term where they do not.  Worked example from ML: https://gist.github.com/pgwilliams/8c742d68878b1fda0638a798668e42f2    also http://build.fhir.org/ig/IHTSDO/snomed-ig/branches/lawley-patch-1/CodeSystem-CodeSystemDesignationUseExample1.html 
On question if this should be part of core spec or remain in SNOMED IG we can consider if this is of use to any other Terminology eg LOINC or RxNorm.

12 Jan Update: @Rob Hausam looking for clarity to take forward with Vocab group.   How to align this with other in-flight trackers (eg https://jira.hl7.org/browse/UP-107) that propose expanding designation use which - we think - seeks to overload designation use in a way that wouldn't ( ?) allow more than one value at the same time and these features of designations can vary independently.

12 Jan Proposal:   All 3 elements (including designation type) should be included in our proposed extension.   SNOMED implementations would then pick the most appropriate designation.use value from whatever set is offered in the spec   eg FSN where it is an FSN (because - although also considered 'preferred' - these are seldom used for user interfaces), PreferredForLanguage where we have the preferred term for a given language/dialect and Synonym for anything else.

26 Jan: RH update - is ongoing discussion.  Attempting "best of both worlds" approach.  Not on the Vocab group's agenda, won't be in R4B.    Question from ML about display vs preferredForLanguage here.  Proposed extension to list of designation use will necessitate repetition of designations where they have multiple uses.   See DK example here:  http://build.fhir.org/ig/IHTSDO/snomed-ig/branches/duc/ValueSet-DrugValueSetExample1.json.html

RH: Suggestion that Ontoserver and/or Snowstorm could try an implementation of our extension.   Clients are expected to ignore extensions that they don't understand.

9 Feb 2021 ML Experience with NL and LOINC.  Could we explore using Language tag with a private X language (eg nl-x-sctlang-87587989-78574801 BCP 47: privateuse = "x" 1*("-" (1*8alphanum)) ) and the language reference set id - ie allows for things like Patient Friendly Terms.   The preferred term would be mapped to the display element.   Language tags allows for weighted preferences (ie fall back options).  Pros:  avoids an extension and re-uses an existing part of the specification.  DK "No reason not to implement this, the two approaches are not in conflict".   Question: is "Preferred for Language" definitely happening?   RH: Yes

23 Feb 2021 RH brought up discussion with Vocab group.  Check in on tracker UP-107. DK Still a requirement to present results (eg expansion) with the language refsets visible (to know which designation was in which langrefset) - better to use extension or overload core spec?   Querying is fine, issue is making clear what is being returned. Suggested possible to use the BCP47 refset form in the language element.   Difficulty when returning fall back options as display term is that we can't say what we fell back to.

9 March 2021 DK An implementation is now needed.   DK tried out with Snowstorm:  BCP-47 works but not for extension language referencesets (also for designation)  ( note dialect alias configured in application.properties is a separate solution which could also be improved: https://github.com/IHTSDO/snowstorm/blob/master/src/main/resources/application.properties#L217 ).  SM NL BCP-47solution getting great feedback.

23 March 2021 DK Testing Snowstorm which looks at designation and language headers.   Just needs attention especially for extension content.  

20 April 2021 RH Looking to target next ballot round.   Could we host this extension ourselves in the meantime and target May connectathon? @Peter Williams

27 July RH & ML:- Still a work in progress. DK will return Aug 1; we should follow up with him next time.

ML:- Potentially fall into R5 on Ontoserver.

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.

SNOMED FHIR Implementation Guide

1

@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/