Three different approaches to automatically creating display terms for postcoordinated expressions are presented, ranging from the simplest to the more complex.
- Replace concept identifiers with terms
- Apply simple term rules
- Apply description templates and rules
Please note that alternative, and more advanced approaches are possible.
When deciding what approach to apply, the following questions need to be considered:
- How close does the term need to match the spoken clinical language?
- Are resources available to develop and maintain the transformation rules and templates?
Replace Concept Identifiers with Terms
The simplest approach to generating display terms for a postcoordinated expression is to simply replace the concept identifiers with a term or description associated with the concept (preferably the preferred term of the applied language reference set). The result of this transformation leads to an expression that doesn't match the clinical language, but it may still be sufficient for the end-users to correctly interpret the semantics of the expression. The table below shows examples of this approach.
| Expression | Approach | Display term |
|---|---|---|
| 397181002:363698007=23416004 |
| "|Open fracture|:|Finding site|=|Bone structure of ulna|" |
336863008:272741003=7771000 | “|Excision of cyst of lung|:|Laterality|=|Left|” |
Simple Term Rules
To increase the human readability of the expressions, simple term rules can be applied in conjunction with the replacement of concept identifiers. Part of this involves avoiding the use of compositional grammar symbols in the terms, which can be achieved in different ways, e.g.
- Replace symbols with predefined terms
- Remove symbols and replace attributes with a ","
The table below exemplifies the transformation rules that can be used to replace compositional grammar symbols.
| Symbol | Term |
|---|---|
| : | with a / with an |
| = | of |
| , | and |
| + | and |
Examples of this approach are illustrated in the table below:
Expression | Approach | Display term |
|---|---|---|
397181002:363698007=23416004 |
| "open fracture with a finding site of bone structure of ulna" |
336863008:272741003=7771000 | “excision of cyst of lung with a laterality of left” | |
| 397181002:363698007=23416004 |
| "open fracture, ulna" |
| 336863008:272741003=7771000 | “excision of cyst of lung, left” |
Description Templates
In some situations, description templates may be applied to ensure that the display terms of the expressions match the clinically spoken language more closely. This approach may be particularly appropriate to consider in situations where the postcoordinated expressions were originally generated using an expression template. In these cases, a corresponding description template and associated term rules may be developed more easily than when the expression was built by another method.
Table Appendix A:-1 illustrates the expression template, description template and term rules for creating expressions that represent a disorder with a fracture morphology and a finding site of some bone structure. The description template specifies that the term associated with the morphology concept is always followed by the term associated with the bone structure concept, and these two terms should be separated by the term ‘of’. Associated with this description template is a set of term rules, but please note that in a real implementation, additional rules may be included to refine the transformation and ensure a proper transformation in all cases (for more information, see general rules for generating descriptions for templates).
| Expression template | Description template | Example term rules |
|---|---|---|
[[+id(<< 64572001 |Disease| @disorder]]: [[1..*]] { [[1..1]] 116676008 |Associated morphology| = [[1..1]] 363698007 |Finding site| = | [[$fractureMorphology]] of [[$boneStructure]] | $boneStructure
|
$fractureMorphology
|
Table Appendix A:-1: Example of Expression template, description template and transformation rules for expressions representing fractures.
Table Appendix A:-2 provides two examples of how a description template and a few term transformation rules can lead to human-readable display terms.
| # | Expression slots | Description template | Term transformation | Display term | |
|---|---|---|---|---|---|
| 1 | @fractureMorphology | |fracture, open (morphologic abnormality)| | [[$fractureMorphology]] of [[$boneStructure]] | fracture | "open fracture of ulna" |
| @boneStructure | |bone structure of ulna (body structure)| |
→ ulna | |||
| 2 | @fractureMorphology | |fracture, closed (morphologic abnormality)| | fracture → closed fracture | “closed fracture of distal ulnar epiphysis“ | |
| @boneStructure | |structure of distal ulnar epiphysis (body structure)| |
→ distal ulnar epiphysis | |||
Table Appendix A:-2: Examples of description templates applied in conjunction with term transformation rules
Feedback
Overview
Content Tools
Apps