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 (

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

...

   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 

...

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 

...