SNOMED CT Diagramming Specification

This document defines the recommended diagramming specification for representing SNOMED CT concepts, expressions, and relationships in a clear, consistent, and unambiguous way. It establishes a standard visual language to support effective communication, reduce interpretation errors, and improve efficiency when creating and reading diagrams.

By providing common notation, layout rules, and templates for widely used tools, this guideline ensures that diagrams across SNOMED International publications share a consistent style and structure. It is intended for all members of the SNOMED CT community of practice who need to represent clinical concepts, definitions, or expression relationships visually, and serves as a foundation for precise, high-quality documentation.

Introduction

Diagram Types

Diagram Elements

Layout

Examples

Appendix

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