Validate Concept Definitions and Expressions

Overview

Concept Definitions

A concept definition is a set of one or more axioms that partially or sufficiently specify the meaning of a SNOMED CT concept.

Concept Definition Validation Requirements

Concept definitions must conform to the SNOMED CT Concept Model as specified by the machine readable concept model. A concept with a definition that does not conform to the concept model cannot be accurately classified.

Service Requirements for Concept Definition Validation

• Terminology services supporting SNOMED CT authoring must validate concept definitions based on concept model rules.

• Services only for terminology use do not need to meet this requirement.

SNOMED CT Expressions

An expression is a structured combination of one or more concept identifiers that represents an idea.

Example

284196006:363698007=770850006

Example (with terms)

284196006 |burn of skin| : 363698007 |finding site| = 770850006 |Skin structure of left index finger|

Expression Validation Requirements

Expressions should conform to the SNOMED CT Concept Model and be classifiable by a description logic classifier.

Transforming Invalid Expressions to Valid Expressions

• Move refining attributes into valid groups.

• Nest refinements where required.

• Move context attributes into a context wrapper.

Example Transformation (Laterality applied to body structure): Invalid:

71620000 |fracture of femur| : 272741003 |laterality| = 7771000 |left|

Valid:

=== 7523003 |Injury of thigh| +
    46866001 |Fracture of lower limb| :
        { 363698007 |Finding site| = ( 71341001 |Bone structure of femur| :
            272741003 |laterality| = 7771000 |left| ),
          116676008 |Associated morphology| = 72704001 |Fracture| }

Service Requirements for Expression Validation

Services supporting use of postcoordinated expressions should support expression validation.

Requirements and Options

Services Required

Service Name and Status	Input	Response
Validate expression RECOMMENDED	Edition and Version Expression to be validated Optional: Language/dialect1	Indication of whether the expression is valid or invalid If the expression is invalid an indication of the reason for failure of validation Syntax error including: Character position of first syntax error, and/or More specific error message(s). Concept model validation error including: Character position of start of invalid element and/or Reference to failed concept model rule(s). Terming errors including: Indication of any terms in the expression that do not match valid descriptions for the identified concept.
Transform invalid expression OPTIONAL	Edition and Version Invalid candidate expression for adjustment	Structurally adjusted valid expression An error message if it is not possible to transform to valid expression
Validate concept definition(s) ONLY REQUIRED FOR AUTHORING	Edition and Version Identifier(s) of concept(s) to be validated	Indication of validation results for one or more concepts including Nature of error If appropriate a reference to a failed concept model rule

Interdependencies

Required By

• 3.2.3 EHR Data Entry

• 3.2.2 EHR Data Entry Design

• 3.8 Support Terminology Authoring and Review

Depends On

• 4.1 Select Edition and Version

• 4.2 Get a Concept, Description or Relationship

• 4.3 Get Terms for a Concept

• 4.4 Get Definition of a Concept

• 4.5 Get and Test Concept Subtypes and Supertypes

• 4.8 Find Concepts

• 4.13 Get Concept Model Rules

Service Examples

Snowstorm API

Validate concept definition:

POST [snowstorm]/browser/{branch}/validate/concept

Response: JSON object with concept, descriptions, axioms, relationships.

Validate concept definitions (multiple):

POST [snowstorm]/browser/{branch}/validate/concepts

FHIR API

No direct SNOMED CT expression validation services.

MySQL Example Database

• No direct support for expression validation, but can validate using concept model rules and expression constraints.

Notes

• Language/dialect should be specified if service returns terms.