This code system http://hl7.org/fhir/filter-operator defines the following codes:
\n \n \n \n \n \n \n \n \n \n \n \n Code\n \n \n \n | \n \n \n \n \n \n \n \n Display\n \n \n \n | \n \n \n \n \n \n \n \n Definition\n \n \n \n | \n \n \n \n \n \n \n \n Comments\n \n \n \n | \n \n \n \n
\n \n \n \n \n \n \n \n =\n \n \n \n \n \n \n \n | \n \n \n \n Equals | \n \n \n \n The specified property of the code equals the provided value. | \n \n \n \n | \n \n \n \n
\n \n \n \n \n \n \n \n is-a\n \n \n \n \n \n \n \n | \n \n \n \n Is A (by subsumption) | \n \n \n \n Includes all concept ids that have a transitive is-a relationship with the concept Id provided as the value, including the provided concept itself (include descendant codes and self). | \n \n \n \n The definition of is-a is that all the properties of the value are true for the specified property of the code, which means that a code has an is-a relationship with itself. To exclude the root code, use descendent-of | \n \n \n \n
\n \n \n \n \n \n \n \n descendent-of\n \n \n \n \n \n \n \n | \n \n \n \n Descendent Of (by subsumption) | \n \n \n \n Includes all concept ids that have a transitive is-a relationship with the concept Id provided as the value, excluding the provided concept itself i.e. include descendant codes only). | \n \n \n \n The definition of is-a is that all the properties of the value are true for the specified property of the code. \n\nSpelling note: "descendant" is a more correct spelling, but the spelling "descendent" is maintained in the code for backwards compatibility reasons | \n \n \n \n
\n \n \n \n \n \n \n \n is-not-a\n \n \n \n \n \n \n \n | \n \n \n \n Not (Is A) (by subsumption) | \n \n \n \n The specified property of the code does not have an is-a relationship with the provided value. | \n \n \n \n | \n \n \n \n
\n \n \n \n \n \n \n \n regex\n \n \n \n \n \n \n \n | \n \n \n \n Regular Expression | \n \n \n \n The specified property of the code matches the regex specified in the provided value. | \n \n \n \n | \n \n \n \n
\n \n \n \n \n \n \n \n in\n \n \n \n \n \n \n \n | \n \n \n \n In Set | \n \n \n \n The specified property of the code is in the set of codes or concepts specified in the provided value (comma-separated list). | \n \n \n \n | \n \n \n \n
\n \n \n \n \n \n \n \n not-in\n \n \n \n \n \n \n \n | \n \n \n \n Not in Set | \n \n \n \n The specified property of the code is not in the set of codes or concepts specified in the provided value (comma-separated list). | \n \n \n \n | \n \n \n \n
\n \n \n \n \n \n \n \n generalizes\n \n \n \n \n \n \n \n | \n \n \n \n Generalizes (by Subsumption) | \n \n \n \n Includes all concept ids that have a transitive is-a relationship from the concept Id provided as the value, including the provided concept itself (i.e. include ancestor codes and self). | \n \n \n \n The definition of is-a is that all the properties of the value are true for the specified property of the code, which means that a code has an is-a relationship with itself. To exclude the root code, add it explicitly to as an exclude | \n \n \n \n
\n \n \n \n \n \n \n \n exists\n \n \n \n \n \n \n \n | \n \n \n \n Exists | \n \n \n \n The specified property of the code has at least one value (if the specified value is true; if the specified value is false, then matches when the specified property of the code has no values). | \n \n \n \n | \n \n \n \n
\n\t\t\n\t\t\n \n \n \n \n \n child-of\n \n \n \n \n \n \n \n | \n \n \n \n Child Of | \n \n \n \n Only concepts with a direct hierarchical relationship to the index code and no other concepts. This does not include the index code in the output. | \n \n \n \n | \n \n \n \n
\n\t\t\n\t\t\n \n \n \n \n \n descendent-leaf\n \n \n \n \n \n \n \n | \n \n \n \n Descendent Leaf | \n \n \n \n Includes concept ids that have a transitive is-a relationship with the concept Id provided as the value, but which do not have any concept ids with transitive is-a relationships with themselves. | \n \n \n \n | \n \n \n \n
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