Replacement slots serve as a placeholder for a value that is not known at the time of authoring, but which can be completed at a subsequent time using data recorded elsewhere (such as in an information model or entered into a data entry form). A slot indicates that it may be replaced by a value by including a plus sign (
) as the first symbol within the slot. Replacement slots may be used in an expression template wherever a concept, expression or symbol may appear within an expression. Focus concept
A replacement slot may be used to delay the selection of a focus concept in an expression. For example, the expression template below uses a slot to indicate that the focus concept in the expression can be replaced with any appropriate SNOMED CT expression. This expression template represents any expression with a single refinement in which the
| Concept |
|---|
| ShowParts | term |
|---|
| t | 272741003|Laterality| |
|---|
|
equals | Concept |
|---|
| ShowParts | term |
|---|
| t | 24028007|Right| |
|---|
|
.| Scg expression |
|---|
| Border | ridge |
|---|
| ShowFormat | block |
|---|
|
[[+]]: 272741003 |Laterality| = 24028007 |Right| |
If the following values are provided to complete the slot:
| Scg expression |
|---|
|
182245002 |Entire upper limb|
182281004 |Entire lower limb|
244486005 |Entire eye|
1910005 |Entire ear| |
then the expressions that result from processing the template would be:
| Scg expression |
|---|
|
182245002 |Entire upper limb|: 272741003 |Laterality| = 24028007 |Right|
182281004 |Entire lower limb|: 272741003 |Laterality| = 24028007 |Right|
244486005 |Entire eye|: 272741003 |Laterality| = 24028007 |Right|
1910005 |Entire ear|: 272741003 |Laterality| = 24028007 |Right| |
Attribute Value
A replacement slot may also be used to replace an attribute value in an expression. For example, the expression template below represents any expression with a focus concept of
| Concept |
|---|
| ShowParts | term |
|---|
| t | 404684003 |Clinical finding| |
|---|
|
and a refinement which uses the attribute
| Concept |
|---|
| ShowParts | term |
|---|
| t | 363698007 |Finding site|. |
|---|
| ShowFormat | inline |
|---|
|
The value of the
| Concept |
|---|
| ShowParts | term |
|---|
| t | 363698007 |Finding site| |
|---|
|
attribute may be replaced by any valid value at a future time.
| Scg expression |
|---|
| Border | ridge |
|---|
| ShowFormat | block |
|---|
|
404684003 |Clinical finding|: 363698007 |Finding site| = [[+]] |
...
| Scg expression |
|---|
| Border | ridge |
|---|
| ShowFormat | block |
|---|
|
53120007 |Upper limb structure| |
...
| Scg expression |
|---|
| Border | ridge |
|---|
| ShowFormat | block |
|---|
|
404684003 |Clinical finding|: 363698007 |Finding site| = 53120007 |Upper limb structure| |
...
| Scg expression |
|---|
| Border | ridge |
|---|
| ShowFormat | block |
|---|
|
53120007 |Upper limb structure|: 272741003|Laterality| = 7771000 |Left| |
...
| Scg expression |
|---|
| Border | ridge |
|---|
| ShowFormat | block |
|---|
|
404684003 |Clinical finding|: 363698007 |Finding site| = (53120007 |Upper limb structure|: 272741003|Laterality| = 7771000 |Left|) |
Please note that the template processor must add round brackets around the subexpression to ensure that the resulting expression is syntactically valid.
Attribute Name
A replacement slot may also be used to replace an attribute name in an expression. For example, the expression template below represents any expression with a focus concept of
| Concept |
|---|
| ShowParts | term |
|---|
| t | 404684003 |Clinical finding| |
|---|
|
and a refinement whose value equals
| Concept |
|---|
| ShowParts | term |
|---|
| t | 58718002 |Rheumatic fever| |
|---|
| ShowFormat | inline |
|---|
|
The attribute name in the expression may be replaced by any valid attribute concept at a future time.
| Scg expression |
|---|
| Border | ridge |
|---|
| ShowFormat | block |
|---|
|
404684003 |Clinical finding|: [[+]] = 80166006 |Streptococcus pyogenes| |
...
| Scg expression |
|---|
| Border | ridge |
|---|
| ShowFormat | block |
|---|
|
42752001 |Due to|
255234002 |After| |
then the expressions that result from processing the template would be:
| Scg expression |
|---|
| Border | ridge |
|---|
| ShowFormat | block |
|---|
|
404684003 |Clinical finding|: 42752001 |Due to| = 80166006 |Streptococcus pyogenes|
404684003 |Clinical finding|: 255234002 |After| = 80166006 |Streptococcus pyogenes| |
...