2021-05-06 - SLPG Meeting

2021-05-06 - SLPG Meeting

Date & Time

20:00 to 21:00 UTC Thursday 6th May 2021

Location

Zoom meeting link (password: 764978)

Goals

  • Discuss feedback on transformation implementation

  • Introduce the process for sharing expression examples

  • Continue discussion on dynamic templates

Attendees 

  • Chair: @Former user (Deleted)

  • Project Group: @Anne Randorff Højen@Ed Cheetham@michael lawley@Feikje Hielkema (Unlicensed)@Jon Zammit

Agenda and Meeting Notes

Description

Owner

Notes

Description

Owner

Notes

Welcome and agenda

@Former user (Deleted)

 

Postcoordination Transformations

 

  • Discuss feedback on transformation implementation

    • Chat comment: "I think it would be useful to be able to syntactically distinguish between certain forms, specifically CTU and the other forms (CF and NNF)"

    • Expected result when expression equivalent to a precoordinated concept: "=== 195967001 |Asthma (disorder)| +
                  111273006 |Acute respiratory disease (disorder)| :
                  { 263502005 |Clinical course (attribute)| = 424124008 |Sudden onset AND/OR short duration (qualifier value)| }
                  { 363698007 |Finding site (attribute)| = 89187006 |Airway structure (body structure)| }"

    • Expected result when an expression is equivalent to an existing expression (that you've already classified)

      • When are two expressions the same?

    • Expected result What would the NNF look like if one expression classifies as a subtype of another expression?

      • E.g. Expression 1 - 363443007 |Malignant tumor of ovary| : 272741003 |Laterality| = 24028007 |Right|

      • E.g. Expression 2 - 363443007 |Malignant tumor of ovary| :
        272741003 |Laterality| = 24028007 |Right|,
        42752001 |Due to| = 218190002 |Exposure to radiation|

      • How should the term be constructed? E.g. based on close-to-user-form

        • 12345061 | Malignant tumor of ovary: Laterality = Right | : { 42752001 |Due to| = 218190002 |Exposure to radiation| }

    • Testing more examples

Dynamic Templates

 

  • Continue discussion on dynamic templates

    • 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|

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

        2. 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 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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