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2021-04-08 - SLPG Meeting

2021-04-08 - SLPG Meeting

2025-Sep-05

Date & Time

20:00 to 21:00 UTC Thursday 8th April 2021

Location

Zoom meeting link (password: 764978)

Goals

  • Consider the transformation of postcoordinated expressions to classifiable form

Attendees 

  • Chair: @Former user (Deleted)

  • Project Group: @Rob Hausam, @Anne Randorff Højen, @Peter Jordan (Unlicensed), @michael lawley, @Feikje Hielkema (Unlicensed), @Daniel Karlsson (Unlicensed), @John Snyder (Unlicensed), @Kai Kewley, @Ed Cheetham

Apologies

Agenda and Meeting Notes

Description

Owner

Notes

Description

Owner

Notes

Welcome and agenda

@Former user (Deleted)

 

Postcoordinated Expression Transformations

 

  • National Cancer Registry use case in the Netherlands

  • Brief recap of transformation process

  • Examples of expression transformation

  • Inter-attribute dependencies

    • Acute/Chronic and Inflammation - Adding a clinical course requires specializing the inflammation morphology 

      • E.g. |Pyelonephritis| : |Clinical course| = |Chronic|
        should be
        |Pyelonephritis| : |Clinical course| = |Chronic|, |Associated morphology| = |Chronic inflammation|

      • E.g. |Pyelonephritis| : |Clinical course| = |Sudden onset AND/OR short duration|
        should be
        |Pyelonephritis| : {|Clinical course| = |Sudden onset AND/OR short duration||, |Associated morphology| = |Acute inflammation|

    • Infectious Causative Agents - Adding a |causative agent| = |Domain Bacteria| or |Virus| requires adding a |Pathological process| = |Infectious process|

      • E.g. |Nephritis|: |Causative agent| = |Domain bacteria|
        should be
        |Nephritis|: |Causative agent| = |Domain bacteria|, |Pathological process| = |Infectious process|

    • Congenital and Acquired - Adding an |Occurrence| of |Congenital| to a focus concept with an abnormal morphology, requires adding a |Pathological process| of |Pathological development process|

      • E.g. |Koilonychia|: |Occurrence| = |Congenital|
        should be
        |Koilonychia|: |Occurrence| = |Congenital|, |Pathological process| = |Pathological developmental process|

    • Situations with Explicit Context 

      1. if the procedure context = |Planned|, then the temporal context should be << |Current of specified time|

      2. If the procedure context = |In progress|, then the temporal context should be << |Current|

      3. If the procedure context = |Performed| or |Done|, then the temporal context should be << |Current or past (actual)|

      • Note: for this use case (of |Procedure with explicit context|) perhaps we just recommend (or require) that the full role group is spelled out.

    • Next steps

      • Representation of the content rules

        • Who creates the complete list of rules and how?

        • What formalism?

        • Determine which are mandatory and which are optional

      • Implementation of content rules - e.g.

        • Guided data entry by pre-populating role groups in expression template based on definition of focus concepts (for design-time use, such as mapping)

        • Mandatory content rules could be added to transform process

Postcoordination Expression Processes

All

Postcoordinated expression processes

  • Generic

  • Use case specific

    • Mapping (from an interface term)

    • Terminology binding (using an expression template)

    • Natural Language processing

Postcoordination Use Case Examples

All

Example 1 - Dentistry / Odontogram

  • Requires an expression template to create expressions.

  • Resulting expression still requires a transformation to make it classifiable

Example 2 - Terminology binding

  • Uses a fixed expression template to combine codes entered into separate fields

  • The procedure+laterality example still requires a transformation to make it classifiable

Example 3 - Mapping

  • Design-time activity

  • Map targets may not be able to be fully represented using concept model attributes

  • In many cases, an extension (with primitive concepts) should be recommended where there are gaps in the mapping

  • There may be some cases in which postcoordination is helpful (e.g. LOINC to SNOMED CT map)

Example 4 - Natural Language Processing

  • Usually run-time activity.

  • May require manual confirmation of coding suggestions (unless low clinical risk, eg for suggesting relevant patient records for manual review)

Postcoordination Guidance

@Former user (Deleted) , @Anne Randorff Højen , @Kai Kewley

Practical Guide to Postcoordination

  • Proposal - Use syntax (i.e. braces) to distinguish refinement vs new role group

  • Proposal: Expression forms needed for this (see 3.4 Transforming Expressions)

    • Close to user form - e.g. 83152002 |Oophorectomy| :  405815000 |Procedure device|  =  122456005 |Laser device|

    • Canonical close to user form - e.g. 83152002:405815000=122456005

    • Classifiable form (SCG) - e.g. 83152002:{260686004=129304002,405813007=15497006,405815000=122456005}

      • PLUS Classifiable form (OWL) - e.g.  

        • EquivalentClasses(:123063
             ObjectIntersectionOf (:71388002
                 ObjectSomeValuesFrom(:609096000 ObjectIntersectionOf( ObjectSomeValuesFrom(:260686004 :129304002)
                 ObjectSomeValuesFrom(:405813007 :15497006))))

    • Necessary normal form - e.g. 83152002+416376001:{260686004=129304002,405813007=15497006,405815000=122456005}

      • PLUS Necessary normal form (tables)

        • Relationships:

          • (123063 116680003 83152002) - 0

          • (123063 260686004 129304002) - 0 

          • (123063 405813007 15497006) - 1

          • (123063 405815000 122456005) - 1

    • Primitive expressions - "<<<" (only useful in a mapping context) → .... relies on the assigned identifier (which are necessarily semantically unique).

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