New attributes that are added to the SNOMED CT concept model (or to a SNOMED CT extension) may require their value to be concrete. Concrete values include integers (e.g. 500), decimals (e.g. 2.75), strings (e.g. "PANADOL"), and booleans (e.g. TRUE).
The expression shown below uses both concept values and concrete values to represent a capsule that contains 500 mg of amoxicillin1 . In this case, the dose form, the active ingredient, the basis of strength substance and the strength unit all use a concept as their value, while the strength magnitude is represented using a numeric value. The numeric value is indicated in the expression by the preceding '#' symbol (e.g. #500).
|1||Please note that these example expressions are based on a hypothetical drug concept model, and are not intended to reflect any specific drug model. In these expressions, the SNOMED CT identifiers created with the '9999999' namespace are for example only, and should not be used in a production environment.|
|2||Concrete values of type string are case sensitive and compared using the Unicode Collation Algorithm (http://www.unicode.org/reports/tr10/).|