2021-03-25 - SLPG Meeting

2021-03-25 - SLPG Meeting

Date & Time

20:00 to 21:00 UTC Thursday 25th March 2021

Location

Zoom meeting link (password: 764978)

Goals

  • Consider the processes required for data entry, display, query and exchange of a postcoordinated expression

Attendees 

  • Chair: @Former user (Deleted)

  • Project Group: @Daniel Karlsson (Unlicensed)@Rob Hausam@Ed Cheetham@michael lawley@Kai Kewley@Anne Randorff Højen

Apologies

  • @Peter Jordan (Unlicensed)

Agenda and Meeting Notes

Description

Owner

Notes

Description

Owner

Notes

Welcome and agenda

@Former user (Deleted)

 

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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