Compositional Grammar

Search

SNOMED CT Document Library

    Loading...

You are viewing an old version of this page. View the current version.

Compare with Current View Page History

« Previous Version 3 Next »


It is also possible to nest, one inside the other. Any validmay be enclosed in a pair of brackets, and included as the value of an attribute in another. For example, the followingdescribes a medication product that has a single dose form, which is both a spray and a suspension:

In the example above, note the use of round brackets (i.e. "( )") to identify a nested, as opposed to braces (i.e. "{ }"), which is used to identify attribute groups.

The following examples show how complexmay be build up from simple ones, a layer at a time. This firstdescribes a left hip structure:

This next expression uses the "left hip"above to describe a procedure to replace it:
Applying a further 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 (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.
Finally, the 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.

Feedback
  • No labels