Expression Constraint Language

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Simple

...

Expression Conjunction and

...

Disjunction

Expression constraints can be built up from smaller parts using conjunction (i.e. AND) and disjunction (i.e. OR). The simplest example of this is where the conjunction or disjunction is used between two simple expressions. For example, the following expression constraint is satisfied only by clinical findings which are both a disorder of the lung and an edema of the trunk. This gives the same result as a mathematical intersection between the set of 'disorder of lung' descendants

Scg expression
ShowPartsterm
19829001|Disorder of lung|
 descendants and the set of 'edema of trunk' descendants.
< 19829001 |disorder of lung| AND < 301867009 |edema of
Scg expression
ShowPartsterm
301867009|Edema of trunk|
 descendants.
Scg expression
ShowFormatblock
   < 19829001 |Disorder of lung| AND < 301867009 |Edema of trunk|
Please note that all keywords are case insensitive, so the following two expression constraints are equivalent to the above:
Scg expression
ShowFormatblock
   < 19829001 |
disorder 
Disorder of lung| and < 301867009 |
edema 
Edema of trunk|
Scg expression
ShowFormatblock
   < 19829001 |
disorder 
Disorder of lung| And < 301867009 |
edema 
Edema of trunk|
The next expression constraint is satisfied only by clinical findings which are either a disorder of the lung or an edema of the trunk. This gives the same result as a mathematical union of the set of 'disorder of lung' descendants
Scg expression
ShowPartsterm
19829001|Disorder of lung|
 descendants and the set of 'edema of trunk' descendants
Scg expression
ShowPartsterm
301867009|Edema of trunk|
 descendants. For this reason, an OR operator will usually allow more valid clinical meanings than an AND operator.
Scg expression
ShowFormatblock
  < 19829001 |
disorder 
Disorder of lung| OR < 301867009 |
edema 
Edema of trunk|
Conjunction and disjunction operators may also be combined with the use of the 'member of' function, as shown below:
Scg expression
ShowFormatblock
   < 19829001|
disorder 
Disorder of lung| AND ^ 700043003 |
example 
Example problem list concepts reference set|
This expression constraint is satisfied only by concepts that belong to the 'disorder of lung' hierarchy
Scg expression
ShowPartsterm
19829001|Disorder of lung|
 hierarchy and are also members of the example problem list concepts reference set
Scg expression
ShowPartsterm
700043003|Example problem list concepts reference set|
.

When more than one conjunction or more than one disjunction is used, round brackets can be optionally applied. For example, the following expression constraints are all valid and equivalent to each other:

Scg expression
   < 19829001 |
disorder 
Disorder of lung| AND < 301867009 |
edema 
Edema of trunk|
AND
^ 700043003 |example problem list concepts reference set|
(< 19829001 |disorder of lung| AND < 301867009 |edema of trunk|) AND
^ 700043003 |example problem list concepts reference set|
< 19829001 |disorder of lung| AND (< 301867009 |edema of trunk| AND
^ 700043003 |example problem list concepts reference 
 AND
      ^ 700043003 |Example problem list concepts reference set|
Scg expression
   (< 19829001 |Disorder of lung| AND < 301867009 |Edema of trunk|) AND
         ^ 700043003 |Example problem list concepts reference set|
Scg expression
   < 19829001 |Disorder of lung| AND (< 301867009 |Edema of trunk| AND
         ^ 700043003 |Example problem list concepts reference set|)
However, where a conjunction and disjunction are both used together, it is mandatory to use round brackets to disambiguate the meaning of the expression constraint. For example, the following expression constraint is not valid:
Scg expression
   < 19829001 |
disorder 
Disorder of lung| AND < 301867009 |
edema 
Edema of trunk|
OR
^ 700043003 |example problem list concepts reference 
 OR
         ^ 700043003 |Example problem list concepts reference set|
And must be expressed (depending on the intended meaning) as either:
Scg expression
   (< 19829001 |
disorder 
Disorder of lung| AND < 301867009 |
edema 
Edema of trunk|)
OR
^ 700043003 |example problem list concepts reference 
 OR
         ^ 700043003 |Example problem list concepts reference set|
Or as:
Scg expression
   < 19829001 |
disorder 
Disorder of lung| AND (< 301867009 |
edema 
Edema of trunk|
OR
^ 700043003 |example problem list concepts reference 
 OR
         ^ 700043003 |Example problem list concepts reference set|)

Attribute

...

Conjunction and

...

Disjunction

Conjunction and disjunction may be used within refinements in a variety of ways. The most common way of using these operators in a refinement is to define the conjunction or disjunction of individual attributes.

For example, the expression constraint below, in which the comma between the two attributes represents conjunction, is satisfied only by clinical findings which have both a finding site of pulmonary valve structure (or subtype) and an associated morphology of stenosis (or subtype).

Scg expression
   < 404684003 |
clinical 
Clinical finding|:

363698007 |finding 

         363698007 |Finding site| = << 39057004 |
pulmonary 
Pulmonary valve structure|,

116676008 |associated 

         116676008 |Associated morphology| = << 415582006 |
stenosis
Stenosis|
This expression constraint can equivalently be expressed as:
Scg expression
   < 404684003 |
clinical 
Clinical finding|:

363698007 |finding 

         363698007 |Finding site| = << 39057004 |
pulmonary 
Pulmonary valve structure|
AND
116676008 |associated morphology| = << 415582006 |stenosis
 AND
         116676008 |Associated morphology| = << 415582006 |Stenosis|
The following example uses the disjunction operator (OR) to represent the disjunction of two attributes. This constraint is satisfied only by clinical findings which have either an associated morphology of 'infarct' (or subtype) or are due to a myocardial infarction (or subtype).
Scg expression
   < 404684003 |
clinical 
Clinical finding|:

116676008 |associated 

         116676008 |Associated morphology| = << 55641003 |
infarct
Infarct|
OR
42752001 |due to| = << 22298006 |myocardial 
 OR
         42752001 |Due to| = << 22298006 |Myocardial infarction|
When more than one conjunction or more than one disjunction is used in a refinement, round brackets can be optionally applied. For example, the following expression constraints are all valid and equivalent to each other:
Scg expression
   < 404684003 |
clinical 
Clinical finding|:

363698007 |finding 

         363698007 |Finding site| = << 39057004 |
pulmonary 
Pulmonary valve structure|
AND
116676008 |associated morphology| = << 415582006 |stenosis| AND
42752001 |due to| = << 445238008|malignant carcinoid tumor|
< 404684003 |clinical finding|:
( 363698007 |finding site| = << 39057004 |pulmonary valve structure| AND
116676008 |associated morphology| = << 415582006 |stenosis| ) AND
42752001 |due to| = << 445238008|malignant carcinoid tumor|
< 404684003 |clinical finding|:
363698007 |finding site| = << 39057004 |pulmonary valve structure| AND
( 116676008 |associated morphology| = << 415582006 |stenosis| AND
42752001 |due to| = << 445238008|malignant carcinoid tumor| 
 AND
         116676008 |Associated morphology| = << 415582006 |Stenosis| AND
         42752001 |Due to| = << 445238008|Malignant carcinoid tumor|
Scg expression
   < 404684003 |Clinical finding|:
         (363698007 |Finding site| = << 39057004 |Pulmonary valve structure| AND
          116676008 |Associated morphology| = << 415582006 |Stenosis| ) AND
          42752001 |Due to| = << 445238008|Malignant carcinoid tumor|
Scg expression
   < 404684003 |Clinical finding|:
         363698007 |Finding site| = << 39057004 |Pulmonary valve structure| AND
         (116676008 |Associated morphology| = << 415582006 |Stenosis| AND
          42752001 |Due to| = << 445238008|Malignant carcinoid tumor| )
However, where a conjunction and disjunction are both used together in a refinement, it is mandatory to use brackets to disambiguate the meaning of the expression constraint.

For example, the following expression constraint is not valid:

Scg expression
   < 404684003 |
clinical 
Clinical finding|
:
363698007 |finding site| = << 39057004 |pulmonary valve structure| AND
116676008 |associated morphology| = << 415582006 |stenosis| OR
42752001 |due to| = << 445238008|malignant carcinoid 
 :
         363698007 |Finding site| = << 39057004 |Pulmonary valve structure| AND
         116676008 |Associated morphology| = << 415582006 |Stenosis| OR
         42752001 |Due to| = << 445238008|Malignant carcinoid tumor|
And must be expressed (depending on the intended meaning) as either:
Scg expression
   < 404684003 |
clinical 
Clinical finding|
: 
 :
         (363698007 |
finding 
Finding site| = << 39057004 |
pulmonary 
Pulmonary valve structure|
AND
116676008 |associated morphology| = << 415582006 |stenosis|) OR
42752001 |due to| = << 445238008|malignant carcinoid 
 AND
          116676008 |Associated morphology| = << 415582006 |Stenosis|) OR
          42752001 |Due to| = << 445238008|Malignant carcinoid tumor|
Or as:
Scg expression
   < 404684003 |
clinical 
Clinical finding|
:
363698007 |finding site| = << 39057004 |pulmonary valve structure| AND
( 116676008 |associated morphology| = << 415582006 |stenosis| OR
42752001 |due to| = << 445238008|malignant carcinoid tumor| )

...

 :
         363698007 |Finding site| = << 39057004 |Pulmonary valve structure| AND
         (116676008 |Associated morphology| = << 415582006 |Stenosis| OR
          42752001 |Due to| = << 445238008|Malignant carcinoid tumor| )

Attribute Group Conjunction and Disjunction

Similarly, conjunction and disjunction may be defined between attribute groups. The following expression constraint is satisfied only by clinical findings which either have a finding site of pulmonary valve structure (or subtype) and an associated morphology of stenosis (or subtype), OR have a finding site of right ventricular structure (or subtype) and an associated morphology of hypertrophy (or subtype).

Scg expression
   < 404684003 |
clinical 
Clinical finding|:


         {363698007 |
finding 
Finding site| = << 39057004 |
pulmonary 
Pulmonary valve structure|,

116676008 |associated morphology| = << 415582006 |stenosis|} OR
{ 363698007 |finding site| = << 53085002 |right ventricular structure|,
116676008 |associated morphology| = << 56246009 |hypertrophy|}

...


          116676008 |Associated morphology| = << 415582006 |Stenosis|} OR
         {363698007 |Finding site| = << 53085002 |Right ventricular structure|,
          116676008 |Associated morphology| = << 56246009 |Hypertrophy|}

Attribute Value Conjunction and Disjunction

Conjunction and disjunction can also be applied to attribute values. The example below is satisfied only by members of the adverse drug reactions reference set for GP/FP health issue, which have a causative agent that is either a subtype of pharmaceutical / biologic product or a subtype of substance.

Scg expression
   ^ 450990004 |
adverse 
Adverse drug reactions reference set for GP/FP health issue|:

246075003 |causative 

         246075003 |Causative agent|
=
 =
               (< 373873005 |
pharmaceutical 
Pharmaceutical / biologic product| OR < 105590001 |
substance
Substance|)
Similarly, attribute values can also use conjunction. The following expression constraint is satisfied only by clinical findings with an associated morphology whose value is both a subtype (or self) of ulcer and a subtype (or self) of hemorrhage.
Scg expression
   < 404684003 |
clinical 
Clinical finding|: 116676008 |
associated 
Associated morphology|
=
 =
         (<< 56208002|
ulcer
Ulcer| AND << 50960005|
hemorrhage
Hemorrhage|)
 

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