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 Date: 2022-04-05


0800-1130 UTC

0900 -1230 BST

Zoom Meeting Details

Topic: SNOMED Editorial Advisory Meeting
Time: Apr 5, 2022 09:00 AM London

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Password: 476343


Marie-Alexandra Lambot                Cathy Richardson

Julie M. James                                 Jaya Sonavane

Trine Angelskar                                Keng-Ling Wallin

Lotti Barlow                                     Philip Brown

Ian Spiers                                         Anna Rossander

Sarah Warren                                    Nicola Ingram

Mark Banks                                       John Snyder

Suzy Roy                                            STEFAN SCHULZ

Elaine Wooler                                    Marina Zanetti

Yongsheng Gao                                 Alistair Carr

Erica Culp                                          Michael Chu                                        


Meeting Files:

Meeting minutes:

The call recording is located here.


  • Obtain consensus on agenda items

Discussion items

1Call to order and role call

This meeting is being recorded to ensure that important discussion points are not missed in the minutes.  The recording will be available to the SNOMED International community.  Joining the meeting by accepting the Zoom prompt declares that you have no objection to your comments being recorded

  • Recording of meeting approved by participants.

Conflicts of interest and agenda review

3UK NHS Digital announcmentJeremy Rogers

Release of SNOMED Code usage statistics.


UK Primary Care data had been collected 2019-2021 and will be released publicly representing use of SNOMED CT concepts.  A description of the types of data that will be released was presented.  Precision rounded up to the closest 10 for number of uses.

Can be used to guide SNOMED in terms of inactivations and replacements.  Provides analytical support for use of SNOMED CT concepts and relationships amongst them.

3Inactivation of concepts related to legality of abortionJim Case

A request from Argentina to inactivate concepts related to the legality or illegality of "Induced termination of pregnancy" or "abortion" (disorders).  Briefing note attached.


In general, the advisory group felt that the representation of legality or illegality were not in the purview of SNOMED CT due to the differences in each country.  This is especially important in cross border interoperability.  SNOMED proposed that this be extended to all concepts mentioning "illegal" or "legal".  

These originated in ICD-9 but the notion of "illegal" has not carried over into ICD-10 and is represented as a synonym associated with "abortion" in the ICD-11 foundation.

This would not prevent NRCs from adding such content to their extensions.


Concepts related to "illegal" and "legal" abortion will be inactivated and pointed to a prent term agnostic to legality.

  • SNOMED CT content team to inactivate "Induced termination of pregnancy" concetps that specify "legal" or "illegal".
4X (person) vs. X of subject (person)Jim Case

A question from a member country on when to use "X (person)" vs. "X of subject (person)" has exposed issues with determination of equivalence in information models that either split the relationship from the condition vs. using a precoordinated Situation concept to represent the SUBJECT RELATIONSHIP CONTEXT.

3/15/2022 - Update

A report on the use of person concepts as values for the SUBJECT RELATIONSHIP CONTEXT attribute is located at:

  • Are familial relationships Roles or Persons?
  • Given "X of subject" is primarily used as the value for this attribute, should these concepts be moved out from the Person hierarchy into their own "value set"? 
  • Is Person the correct hierarchy for these to be placed?  
  • How do we handle "Fetus of subject" given the sensitivity of some members of having a (person) semantic tag? This is needed when procedures or conditions are performed/recorded in a fetal record as opposed to a maternal record.


"X of person" was introduced to support the SUBJECT_RELATIONSHIP_CONTEXT of Situations.  Monique van Berkumwill look for some history on why they were added. Suggested that the ECE might have some history on these.  Question is whether we need to separate out the relationship values from "persons" as a class?

Background -

The main distinction made in the reference paper is that between an "Entity" and the "Role" played by an Entity.  However, this distinction is not made within the person hierarchy, with << 444148008 |Person in family of subject (person)| primarily representing roles that Person entities play being in the same Person hierarchy. Since the 444148008 |Person in family of subject (person)| is primarily used as values for the SUBJECT RELATIONSHIP CONTEXT attribute, we can question why it is in the Person entity hierarchy.

A question raised by the reference provided is whether a well-established role (e.g. father) can also exist as an entity?  Can a father exist as a standalone entity without the establishment of a relationship to another entity?


We are not separating roles from entities in the current hierarchies.  Because these are classes and not instances, we are constrained in how we can represent them.  This is more challenging in the current context of changing family constructions.  Father/mother and other familial relationships need to be explicit in that what is being referred to is the hereditary/genetic relationship between the patient and the subject relationship context. Need to consider the social context in this as well.  Do we need to separate out biological from social familial structures?  

In general, there is a feeling that we need to represent both the genetic and social constructs of familial relationships.  The X of subject (person) concepts were developed to support a specific attribute and should they be separated out.  

Fetus of subject is another issue. Do we need to be more specific in the definition of the SUBJECT RELAITONSHIP CONTEXT so we define explicitly what type of relationship we are trying to represent.  Is this an entity to entity relationship or an entity to role relationship?  

A related question to fetus.  How do we distinguish between the mather and the fetus in some procedures and disorders.

This is an issue in mental health as well that crosses over the biological and social aspects of relationships.


Background will be investigated.  The person hierarchy needs some review and rationalization.

Background document posted above.  Will review for next meeting.

5Flavors of NULL; data not recorded, activity not done in Findings HierarchyJim Case

We have received a request for a concept "Patient race not recorded" as a subtype of 312863000|Patient data not recorded (finding)| along with a request to create a new Observable entity and finding value to allow for modeling of concepts related to clinical documentation not being recorded.  


INTERPRETS = Demographic detail (observable entity) as well as subtypes specifying the type of demographic information.

HAS INTERPRETATION = Not documented (qualifier value)

This type of concept appears to be a "reason" for missing data as opposed to a NULL value.  FHIR incorporates these "flavors of NULL" in many of their value sets.

Are these really findings?


There is a use case for recording the reason that data are missing.  Suggested that these be qualifiers as opposed to findings. These should be agnostic as to what data are missing but support the reason why the data are missing.  


These have been identified as useful concepts that would be added as qualifier values to represent flavors of null.  Need to reference the FHIR value set for a "starter" set of concepts to consider.

6Change to definition of 246454002 |Occurrence (attribute)|Jim Case

The current definition of the Occurrence attribute is:

"This attribute refers to the specific period of life during which a condition first presents. However, conditions may persist beyond the period of life when they first present."

In many cases, the presentation of a condition occurs after the period of life in which it is observed.  This is especially true when there is a continuum of time periods; where it can be determined that a disorder actually began prior to the time in which it is observed.  New additions to the 282032007 |Periods of life (qualifier value)| hierarchy to support maternal pregnancy and fetal development phases warrants a revision of the definition of this attribute.

A proposed new definition for the Occurrence attribute is:

"This attribute refers to the specific period of life determined to be the period of onset of a conditionThis may be prior to the actual initial observation and conditions may persist beyond the period of life when they first present."

This issue arose during a remodeling of Birth trauma, where it can be determined that the trauma occurred prior to or during delivery of the child, but is not necessarily noticed until after complete delivery.


Proposed to change the last words of the definition from "when they first present" to something representing when the condition actually started (is realized). 

4/12/2022: revised wording:

OCCURRENCE: The specific period of life determined, possible retrospectively, to be the period of onset of a condition, as opposed to the period when the condition first presents or is diagnosed.  The condition may persist beyond the period when it was first determined to have occurred. 


Definition will be reworked and sent to the EAG for review.

  • Jim Caseto reword definition and send out to EAG for review.
7Moving "at risk" Clinical findings to SituationJim Case

Based on a request from a member country, we seek advice on the potential move of << 281694009 |Finding of at risk (finding)| from the Clinical Findings hierarchy to the Situation hierarchy.


  1. "At risk" is an ambiguous term that could mean either "at low(er) or decreased risk" or "at high(er) or increased risk", although it commonly is used to represent "at increased risk"
  2. Nearly all of the current "At risk (finding)" concepts are primitive and thus difficult to maintain and of limited analytical use
  3. There are a limited number of "At risk (situation)" concepts that are all sufficiently defined using the FINDING CONTEXT = "At risk context (qualifier value)

At risk findings = 254 (5 sufficiently defined, but through multiple primitive parents)

At risk situation = 5

Given the rationale above, it is proposed to inactivate and replace the current finding concepts with new Situation concepts using the terming pattern "At increased risk of X (situation)" based on the change of meaning to be more explicit and the movement to the Situation hierarchy.


  • Should these concepts be simply moved and remodeled (retaining SCTID)?
  • Should these concepts be inactivated and replaced (preferred but potential large impact on users)?
  • If inactivated, which inactivation reason would be used given that the existing terms are ambiguous, but are most frequently used to represent only "increased risk".  It is not necessarily of benefit to add both increased and decreased risk concepts where the latter would not be of much clinical use except in a few cases.


Many of the at risk finding concepts do not have findings or disorders to use as ASSOCIATED FINDING values.

At risk is a disposition.  We have developed predispositions as findings for allergy.  This is a prototype of representation of risk.  What are the requirements for representation of risk.  Is further analysis for the use cases needed? 

There may be a difference between statements of risk that are determined ad hoc and those that are determined through the use of formal assessments.

Do we represent risk as a set of observables?  Propose that a set of modeling exercises to determine the best approach.  

Moving them would clarify the meaning and make them more explicit.  It would also allow for a "cleaning out" of risks of questionable value.  

This would only be the first step in looking at ways to represent risk moving forward.


Consensus that this would be a good first step and would help to inform later needs for risk. Terms will be inactivated and replaced based on change of meaning.


Measurement Findings:

Proposed changes to FSNs

Update on Positive/Negative findings

Paul Amos
  • Proposed changes to FSNs: Please read the attached Briefing before the meeting and if possible return your comments for discussion at the meeting.


So far, with limited input, there has been positive response to the proposal.  One area where there is an issue is where existing concepts that refer to "increased" are referencing a relative increase as opposed to an above or below reference range. 

Another concern...ambiguity based on the source of the component being measured.  E.g. increased albumin. There are a number of "agnostic" groupers (with regards to specimen) that would need to be addressed as to whether they are ambiguous or not. Should these be resolved at the same time as the remodeling and reterming or handled as a separate phase of the project.  

Consensus that the notion of "relative to last time (or time period)" should not be represented in the international release. There were some in favor of inactivating those that use "increased" or "decreased" as inherently ambiguous.    "Normal" in terms of substances/drug is also ambiguous based on the use case.  Given the many examples of how the terms can be interpreted leads the group to determine that these all need to be inactivated and replaced with more explicit.  The issue is that there is a problem with determining what the inactivation reason would be. Suggested to inactivate the entire hierarchy without replacement and create a new hierarchy with more explicit concepts.


The exposure of a number of issues around interpretation requires further evaluation of the proposed approach for reterming and revision of modeling.  Will be discussed internally and brought back to the EAG for additional review.

9Non-medicinal products/non-therapeutic roles

Proposal for initial phase to remove concepts representing non-medicinal products and non-therapeutic roles from the Substance hierarchy.


Presentation of proposal for relocation of non-substance concepts that are not medical products but are inportant in adverse reaction area.


None.  Informational only



11Next meetingEAGTentative: May 25, 2022 10:30 PDT

1 Comment

  1. Further to agenda item #3 above, I am now very pleased to report that NHS Digital has released into the public domain its data on how often each SNOMED CT code was added as a new coded EPR item within the UK Primary Care setting during each of the two consecutive periods of 12 months starting 1 August 2019. The data is annual, and quasi-national.

    It can be found at SNOMED Code Usage in Primary Care - NHS Digital.

    This published data was aggregated from more than one original mandatory data return provided by individual system suppliers under the GP IT Futures programme, as detailed here: Primary Care Clinical Terminology Usage Report - GP IT Futures Capabilities & Standards

    It is more or less as I had outlined in my presentation:

    • Each annual report lists all SNOMED CT codes from within the SNOMED International core or the UK's Extensions PROVIDED at least one new EPR entry had been made using the code
      • SNOMED codes for medications used (dm+d codes) are however mostly absent, because the original data extracts from contributing supplier systems do not include the prescribing record
      • SNOMED codes received as part of data flows from laboratories sending results are included
    • All counts are rounded to the nearest 10 (ie, an original aggregate value within the range 95-104 is published as 100), except the very small non-zero counts of 1,2,3 or 4 that are instead rendered as an asterisk
      • SNOMED codes that achieved zero usage during the reporting period are not listed at all, even if they were part of the prevailing release of the UK Edition of SNOMED during the reporting period.
    • The published counts are NOT prestandardised to a constant population. Such standardisation across annual reports would be possible by reference to the co-published metadata report, which states the number of patient records from which the counts were likely to have been aggregated (see Primary Care Clinical Terminology Usage Report - GP IT Futures Capabilities & Standards for more information on what that metadata patient count is actually reporting)
    • Two additional columns report whether or not each listed code was "active" within the UK Edition of SNOMED on the first and last days of the reporting period

    The metadata file lists the significant caveats, primarily that (as I also described in my presentation) these are counts of how often clinicians choose to record something. There is therefore only a very weak and unstable correlation between how often codes for clinical phenomena are recorded and the true incidence or prevalence in the real world of the underlying clinical phenomenon. Some clinical phenomena never get coded and others only some of the time. Some conditions may be recorded more than once for the same patient during the same reporting period. The data also displays clear evidence of miscoding (wrong code selected) and undercoding (code selected is true but underspecified). But its hopefully an intriguing start! If it raises more questions than it answers, and so stimulates further research in this area and similar data collections globally, that would be wonderful.