Deciding a Context Representation Strategy
SNOMED CT implementers must develop a clear strategy for representing clinical context, taking into account:
The structure and constraints of existing data models
Cultural preferences and local workflows for data entry
Alignment with national or organizational standards
This strategy must define the division of responsibility between the information model and the terminology model, i.e., which context elements are represented by system fields and which are encoded directly within SNOMED CT concepts.
These decisions impact:
The design of terminology bindings
The structure of user interfaces
The consistency of clinical data interpretation
Context Representation Options
Two general approaches can be used to represent clinical context in SNOMED CT implementations:
Representing context in the information model
Representing context in the terminology
Representing Context in the Information Model
In this approach, only context-free concepts from SNOMED CT are bound to data elements. Contextual details are stored in separate fields in the information model.
Example Terminology Bindings
Diagnosis/Problems:
<< 404684003 |Clinical finding (finding)|Procedures:
<< 71388002 |Procedure (procedure)|Context Fields in the Information Model
These fields may be populated with SNOMED CT concepts representing:
Finding context
Describes the nature of the finding (e.g., suspected, confirmed)
Subject relationship context
Indicates the relationship of the subject to the patient (e.g., family member)
Temporal context
Specifies the time frame (e.g., past, present)
Representing Context in the Terminology
This approach binds to SNOMED CT concepts that include both the clinical meaning and its context, using either:
Pre-coordinated concepts
Postcoordinated expressions
Example Terminology Bindings
Diagnosis/Problems:
<< 404684003 |Clinical finding (finding)|
<< 413350009 |Finding with explicit context (situation)|Procedures:
<< 71388002 |Procedure (procedure)|
<< 129125009 |Procedure with explicit context (situation)|This approach minimizes reliance on custom or ad-hoc fields by using SNOMED CT’s built-in context modeling features.
Pros and Cons of Each Strategy
Representing Context in the Information Model
Pros:
Greater coverage
Not all context combinations are represented in SNOMED CT—this method fills that gap.
Flexibility
Allows systems to dynamically combine findings/procedures with context values.
Cons:
Higher development effort
Requires more complex UI and backend design to manage contextual fields.
Increased user burden
Without thoughtful UI design, clinicians may face longer workflows.
Representing Context in the Terminology
Pros:
Simplified text search
Pre-coordinated concepts (e.g., “History of asthma”) are easier to find.
Efficient data entry
Eliminates the need for separate context fields.
Expandability
New context combinations can be represented via new concepts or post-coordinated expressions.
Cons:
Limited context coverage
Only a subset of possible context variations are pre-coordinated in SNOMED CT.
Terminology maintenance overhead
Requires ongoing updates and careful management.
Reduced alignment with standard models
May not map cleanly to information models like FHIR, which expect discrete context fields.
Choosing the Right Approach
There is no one-size-fits-all solution. The choice between representing context in the information model or in the terminology should be based on:
Implementation goals
Data model architecture
Tooling capabilities
User needs and workflow requirements
A balanced strategy, combining the flexibility of the information model with the efficiency of terminology-based context, often yields the best results.
Careful design ensures that context is represented accurately, consistently, and efficiently throughout the health information system.
Last updated