1

Welcome & apologies

@Daniel Karlsson

Remember recording!

2

Conflicts of interest

@Daniel Karlsson

Non stated!

3

Minutes from previous meeting

@Daniel Karlsson

4

Process observables

@Daniel Karlsson

In the Editorial Guide there is a note/warning that "Some areas of the observable entity hierarchy need clarification and remodeling." See Observable Entity

This work is now scheduled in the area of processes/process observables.

2021-12-20:

415178003 |Process (observable entity)| is a joint superconcept with 246464006 |Function (observable entity)| for some concepts. Further, there is some possible duplication between 415178003 |Process (observable entity)| concepts such as 129003000 |Dressing (observable entity)| and 284967006 |Ability to perform dressing activity (observable entity)|.

5

SDH observables

@Jim Campbell

Slides: 

6

Aggregation and time aspect

@Daniel Karlsson

Slides: https://docs.google.com/presentation/d/1TFU-rqnzNd6x0gizjO_h3CVfaXgQ6uEdlV_zeWoSA3I/edit?usp=sharing

314459004 | Maximum 24 hour diastolic blood pressure (observable entity) | was used as an example and there were concerns about the usefulness of this and similar concepts. Also a discussion of what constituted an "aggregation".

The current model of representing "aggregated" observables (average, min, max, highest, lowest, etc. etc.) using a time aspect distinct from | Single point in time | was considered appropriate with the implication that observables which could conceivably be aggregated would need this attribute specified.

2021-12-20:

Updated slides (above) with a (clearer) definition of "aggregation" and some concept statistics from SNOMED CT and LOINC. Note that the current slides does not include parameters (e.g. max device setting). There is a need for guidance when (and when not) aggregate Observables and non-aggregate Observables should subsume.

7

E2O

@Daniel Karlsson 

@Jim Campbell

@Former user (Deleted)

A number of topics have been identified in the E2O project for discussion in the Observables PG (see presentation here):

• Observables and aggregation - how to represent average, mean, maximum etc. Previously, for the vital signs Observables, aggregation have been represented using primitive stated parents. What subsumption is expected? Examples: "Mean corpuscular volume", 314449000 | Average 24 hour systolic blood pressure (observable entity) |, 8879006 | Creatinine measurement, 24 hour urine (procedure) |

• Precondition time spans, for example 313719006 | 120 minute plasma cortisol measurement (procedure) | - to model or not to model

  • When there are established, international protocols for measurement and the number of variations is relatively small, scalability might be an issue.

  • Representation within SNOMED CT would not be computable beyond identifying distinct time intervals.

  • Present examples for real-world use for next meeting.

• What are the properties:

  • 413064004 | Anti mitochondrial antibody pattern (procedure) |

  • 413066002 | Antinuclear factor titer (procedure) |

  • 51106007 | Leukocyte alkaline phosphatase score (procedure) |

2021-10-18:

For discussion:

• Groupers for lab observables

  • of proposal for grouper concepts to organize hierarchy based on Nebraska Lexicon and X-eHealth survey of EU lab specialties.

  • Some skepticism towards the introduction of primitive intermediates in the Observable hierarchy. Likely difficult-impossible to standardize internationally

  • Provide examples of what can and cannot be achieved with fully defined groupers, particularly using GCIs.

  • Is solutions to this problem better left to the IT-system vendors?

• Results for Evaluation Procedures - E2O differential

  • Results attached .

• Other topics

  • Panels - when is the E2O project to provide guidance for panels. There is a need to collect the yet unsolved issues.

2021-12-20:

Report from E2O call 2021-12-15. Plan for proceeding with project and potential transition is being created.

8

Scale Observables

X

• Scale/score Observables for anesthesia and clinical medicine

• The Anesthesia CRG has submitted a paper to the EAG describing some of the problems of SNOMED in relation to modeling of assessment scales (see )

• See attached presentation for discussion this date: "Clinical Scale Scores20210301"

• Deliverables: 

  1) Anesthesia CRG will proceed with proposing FSN/PT for ASA scale scores as qualifier, including definitions of each value, and proceed with obtaining permission from ASA for publication

• 2) Anesthesia CRG will proceed with proposing FSN/PT for Mallampati scale scores as qualifiers, including definitions of each value, and proceed with obtaining permission from authoritative source for publication

• More complicated use case of Glasgow Coma Scale was discussed briefly to prepare for detailed discussion next meeting.

• Deliverable:  3) Meeting attendees to consider special use case of supporting calculations for Glasgow Coma Scale Total Score from three Ordinal component scores for discussion next meeting

2021-04-19:

Assessment scale hierarchy requirements https://docs.google.com/presentation/d/1b_vmIY7IFjfYuaXd6H-c5GxijEyaFj75wbvreZ4_fkA/edit?usp=sharing

@Former user (Deleted) provided background to the use cases provided by the Anesthesia CRG.

A requirement to represent the scale points of the assessment scales when they correspond to findings, but question is who is responsible for the association between clinical findings in general and scale points. 

There are two use cases which are slightly different: (1) the requirement to be able to use SNOMED CT to encode contents of the EHR and then use that to "populate" assessment scale components, and (2) the requirement to be able to store and communicate results of application of the assessment scales per se using SNOMED CT concepts. Moving from (1) (i.e. a SNOMED CT encoded EHR) to (2) (SNOMED CT encoded assessment scale representation) is non-trivial. There is a discrepancy between the recording of clinical findings (more granular) and the recording of values for assessment instruments (discrete buckets). The challenge is matching the clinical findings to the appropriate value in the assessment. This is not (necessarily) something that is handled within SNOMED. However, assessment scales are also sometimes used as the primary documentation.

2021-05-17:

Some example existing scale observables were discussed in relation to the subsumption expected from any work done to define scale observables. E.g. the Apgar component observables are not subsumed by any observables related to heart rate, respiration, skin color etc. To contrast, pain score observables are subsumed by other pain observables. The group agreed that being able to group scale observables by what the scales assess is a desireable feature of any solution.

2021-06-21:

@Jim Campbell made a presentation at the Anesthesia CRG call about representing assessment scale observables. A key missing piece is the representation of scale points (ordinals) beyond their scale value (e.g. 1, 2, 3, ... for GCS) to include the actual clinical meaning. For GCS, neurologists' input will be sought. Experimentation with the CRG include more complex scales will help produce a decision paper for the EAG.

2021-08-02:

Slides

Scale observables could, when they correspond to e.g. physiological or otherwise established observations, be represented as <base observable> : | Technique | = <the assessment scale>, | Scale type | = | Ordinal|. See example in slides.

IP issues might prohibit the representation of some assessment scale components: Proprietary Names and Works

2021-08-16:

There's been a meeting of the Clinical Reference Group leads about assessment scales and SNOMED CT. A more general discussion about the requirements for assessment scale content is planned for a new meeting September 8. @Former user (Deleted) will present the work done in the Anesthesia CRG with Observables and Findings. Will discuss this presentation with @Jim Campbell and @Daniel Karlsson.

The preferred representation of scale values/points/ordinals was discussed. Currently some concepts for scale values for some assessment scales, or parts thereof, exist in SNOMED CT, e.g. <<386557006 | Glasgow coma scale finding (finding) | but only for the total score, not its components. 

2021-11-15:

Waiting for input from CRGs.

From Anesthesia: "...we would like to see the observables team produce a full set of terms using observable entities for one or two of the scales we have discussed such as GCS and SOFA so we could review suitability for clinical use."

2022-01-24:

Assessment scales for sleep apnea screening: STOP-BANG and Epworth Sleepiness screen.

The STOP-BANG score https://www.mdcalc.com/stop-bang-score-obstructive-sleep-apnea assesses the risk of Obstructive Sleep Apnea. Going back to previous discussions about representations of likelihood, risk and probability, it is proposed to represent these (and similar risk scores) using the following pattern/example:

Additional scores exist in SNOMED CT, 41 <<273249006 |Assessment scales| has the word "risk" in a description. 80943009 |Risk factor (observable entity)| (which is a misnomer) has 28 descendants.

@Jim Campbell to model risk score concepts/sleep scale observables.

9

London meeting

@Daniel Karlsson

Potentially a face-to-face meeting in London April 2-7 2022 https://www.snomed.org/news-and-events/events/business-meeting 

• More focused meeting

  • E.g. E2O and scale observables

  • Could be time to set a more detailed plan for E2O transition

10

Gender observables

Nex discussion page set up:

Gender observables

11

Next meeting

@Daniel Karlsson

Next meeting is Feb 21 2022 20.00 UTC.

Agenda:

• Risk score observables

• Gender (assignment, identity) observables @Jim Campbell

• Interpretation (ordinal scale) observables and ratios @Karim Nashar

@Daniel Karlssonto set up Gender observables page