Conflicts of interest

Notice of recording

•  Members to review edited transcripts and suggest changes.

• Issues from the vital signs modelling

Usage of observables by UKTC:

2018-08-20 - OBSERVABLE Meeting

Discuss this paper in light of the new drug model. Specifically how the new model resolves many of the issues with incorrect inferences related to the IS A hierarchy in substances.

Smashing the strict hierarchy

In spite of not being a strict hierarchy, SNOMED still doesn't have the types of relationships needed to support CDS in specific use cases.

Modularity is an approach that should be evaluated as a potential solution to domain specific use cases. Advantages over refsets: standarization the representation of needed content, a structured approach.

What is SNOMED's policy on addition of content to meet domain specific requirements?

Concerns about patient safety to make corrections being delayed by the release cycle need to be addressed. JTC mentioned the discussions about more frequent releases and would update the EAG when decisions have been made.

JPI mentioned the concern that comes with daily releases. These will be addressed with the final proposal for release schedule. Also mentioned the proposal to convert releases to a service-oriented approach and the potential for continuous release.

•  Develop a policy on the addition of domain specific process content to SNOMED international.

• Batch editing of the disorder/findings hierarchy to transform it into a representation with a "naked kernel" clinical entities hierarchy (no soft defaults)
• Additional auxiliary hierarchies supporting better modeling patterns
• An observation/statement/assertion/phenomena hierarchy that would explicitly represent context (e.g. presence/absence) while supporting correct aggregation of some absence patterns. 

GRE demonstrated a simple representation of the us eof Clinical entities and a resolution of the current Situation artifact of the inverted hierarchy when using "Known absent".

KCA reaffirmed his objection to the use of logical negation in the context of presence/absence findings and the use of a measurement approach that would represent presence/absence without the need for logical negation.

The current Situation model does not correctly represent absence in the hierarchy and this is the primary problem that needs to be resolved.

KCA proposes that the Situation with explicit context hierarchy would be the first subset of content to be placed into a module that is dependent on the Clinical entities (phenomenon) hierarchy. We need to support the need for absence content as used by most large scale EHR systems.

The current released content for absence findings in the Situation hierarchy is incorrect because of the inverted hierarchy.

Revisit the intended meaning and operational consequences of the nine subflavours of 900000000000522004|Historical association reference set (foundation metadata concept)|

• ‘historical associations’ are to be declared between inactive concepts and their candidate active (and so taxonomically reportable) substitute(s).
• Sections within the RefSets Practical and Terminology Services guide mention that such associations exist - though they’re rather silent on what you can or should do with them.
• No obviously visible guidance (e.g. in the new Editorial Guide) on how and why authors should decide what makes a ‘good association’
• Not a lot of understanding of the possible consequences of a bad or missing one.

Summary of discussion from F2F meeting

1. The distinction between Finding and Disease has been and is a cause of confusion for modelers and implementers.
2. The use of implied context for the Clinical findings/Disease hierarchy causes issues for implementers in that other context-types are located in a separate top-level hierarchy.
3. We are currently using the Clinical findings hierarchy as both “Clinical entities” and “Assertions”.
4. It is desirable to have a “pure” clinical entities hierarchy that can be used to populate assertions (clinical statements). Potential names proposed:
a. “Findables”
b. Phenomena
c. Clinical entity
5. A number of the attributes of the Clinical findings concept model are context-type relationships.
6. It was generally agreed that SNOMED should evolve to include a “context-less” set of defined clinical entities that would support the population of a more robust and comprehensive “clinical statement” model.
7. A review of the various extant (and useful) clinical statement models should be undertaken to inform the structure of a SNOMED CT clinical statement model.
8. The current Situation with explicit context model is viewed as a starting point for the development of the SNOMED Clinical statement model.
9. A clear statement regarding the removal of support for the “Soft context” for Clinical findings and Procedures must be communicated to the implementation community.
a. Removal references to soft context from the Editorial guide.
b. Recommended that clinical entities would not be used directly, but only as a component of a clinical statement.
10. Post-coordinated expressions have a number of issues related to construction, determination of equivalence and reusability that make them less appealing as a solution to context.
a. Most large EHR systems implementations do not support post-coordination.
11. The current Situation model simply provided a way to move concepts that were context-laden, out of the ostensibly context-free Clinical findings hierarchy.
12. Logical negation is out of scope.
a. Does not conform with non-binary representations of presence or absence.
13. Any solution should be developed in conjunction with information model developers.
14. We need to develop an incremental approach to this change as it may be viewed as to dramatic for some users.

Potential Actions

•  Write a project charter. Should outline what the end goal of the project is and what the perceived benefits and potential detriments there might be.
•  Propose the creation of a formal project group (Clinical statement project?). The initial though is to create two types of groups, a small, formal work group and a larger project group. These would be modeled after the groups in the drugs project.
•  Write the Terms of Reference for the Project Work Group and the overall Project Group
•  Identify potential members. What is the proposed size of the group. The bigger the group, the more difficult it will be to get consensus. However, without adequate representation, the more chance we will have of getting pushback.
•  Develop a draft strategy and the critical path for addressing the issues that we identify

a. Identification of the specific issues.
b. Predict the potential impact of the terminology
c. Outline that potential issues that might impact users and implementers
d. Develop mitigating strategies for minimizing impact.

•  Notify the Community of practice about the project group and its objectives

a. Solicit feedback from the CoP. That will be our consultation process.
b. Change or revise the terms of reference as needed from input.

•  Begin environmental scan for clinical statement models that can be used as starting points for comparison. Candidates include:

a. HL7 Clinical Statement model: (https://www.hl7.org/implement/standards/product_brief.cfm?product_id=40)
b. FHIR resources: (https://www.hl7.org/fhir/resourcelist.html)
c. CIMI?