It is also possible to nest nest, one inside the other. Any valid may validmay be enclosed in a pair of brackets, and included as the value of an attribute in another another. For example, the following describes followingdescribes a medication product that has a single dose form, which is both a spray and a suspension:
| Scg expression |
|---|
| Border | ridge |
|---|
| ShowFormat | block |
|---|
|
373873005 | |
pharmaceutical Pharmaceutical / biologic product|: |
has spray 7946007 |drug 7946007 |Drug suspension|) |
In the example above, note the use of round brackets (i.e. "( )") to identify a
nested nested, as opposed to braces (i.e. "{ }"), which is used to identify attribute groups.
The following examples show how complex may complexmay be build up from simple ones, a layer at a time. This first describes firstdescribes a left hip structure:
| Scg expression |
|---|
| Border | ridge |
|---|
| ShowFormat | block |
|---|
|
24136001| |
hip laterality leftThis next expression uses the "left hip"
above above to describe a procedure to replace it:
| Scg expression |
|---|
| Border | ridge |
|---|
| ShowFormat | block |
|---|
|
397956004| |
prosthetic Prosthetic arthroplasty of the hip|: |
procedure hip laterality 7771000leftApplying a further
grouped to groupedto the above describes a procedure to replace a left hip by inserting a prosthesis. Note that this example mixes an ungrouped qualification and a grouped qualification. Where this is done, the canonical representation of the expression includes all ungrouped attributes before the grouped ones (
section 7.8.2.4.4.4.2 of the SNOMED CT Technical Implementation Guide [6]see Terminology Services Guide for more details). Please also note that in the previous version of this standard a comma was not permitted between the last ungrouped attribute and the first attribute group – however this comma is now optional to avoid unexpected syntax errors.
| Scg expression |
|---|
| Border | ridge |
|---|
| ShowFormat | block |
|---|
|
397956004| |
prosthetic Prosthetic arthroplasty of the hip|: |
procedure Procedure site - indirect| |
hip laterality left { 363699004|direct device| = 304120007|total hip replacement prosthesis|, 260686004|method| = 425362007|surgical insertion -
{ 363699004|Direct device| = 304120007|Total hip replacement prosthesis|,
260686004|Method| = 425362007|Surgical insertion - action|} |
Finally, the
above may abovemay be included within a contextual wrapper, to describe a procedure that has been performed on a patient to replace a left hip by inserting a prosthesis.
| Scg expression |
|---|
| Border | ridge |
|---|
| ShowFormat | block |
|---|
|
243796009| |
situation Situation with explicit context|: |
procedure done temporal current subject Subject relationship context| |
subject associated = ( 397956004|prosthetic arthroplasty of the hip|: 405814001|procedure site - indirect| = (24136001|hip joint structure|:272741003|laterality| = 7771000|left|){ 363699004|direct device| = 304120007|total hip replacement prosthesis|,260686004|method| = 425362007|surgical insertion - action|}) =
( 397956004|Prosthetic arthroplasty of the hip|:
405814001|Procedure site - indirect| = (24136001|Hip joint structure|:
272741003|Laterality| = 7771000|Left|)
{ 363699004|Direct device| = 304120007|Total hip replacement prosthesis|,
260686004|Method| = 425362007|Surgical insertion - action|} ) } |