Observation Reference Range
The guidance used to interpret the value by comparison to a normal or recommended range. Multiple reference ranges are interpreted as an "OR". Target population(s) may be associated with a reference range.
Constraints
Unique key(s)
- XOR(Observation, Observation Component), XOR(Reference Range Value, Reference Age Range Code)
Stereotype(s)
n/a
Attributes
| Attribute | Type | Multiplicity | Attribute note |
|---|---|---|---|
| Reference Range Value | Range | 0..1 | The actual value of the reference range (as a range interval, not as a coded concept).
Range Value.Unit of Measure Code, for both low end and high end, is optional, and not applicable when the associated observation code or observation component code already states or presupposes a specific unit of measure.
Unit of Measure Code
Value Set:
https://ui.terminologystandardsservice.ca/ui/deeplink?iss=https://terminologystandardsservice.ca/fhir&type=ValueSet&canonicalUrl=https://fhir.infoway-inforoute.ca/ValueSet/x_timeunitsofmeasure
|
| Reference Range Age Code | Codeable Concept | 0..1 | Uniquely specifies the reference used for an age range (as a code from a code system in a value set).
Value Set: To be developed.
Year is a unit of measure in this value set: https://ui.terminologystandardsservice.ca/ui/deeplink?iss=https://terminologystandardsservice.ca/fhir&type=ValueSet&canonicalUrl=https://fhir.infoway-inforoute.ca/ValueSet/x_timeunitsofmeasure
|
| Reference Range Type Code | Codeable Concept | 0..1 | Uniquely specifies which part of the targeted reference population an observation applies to (e.g., normal, recommended, therapeutic, treatment).
Value Set:
https://fhir.infoway-inforoute.ca/ValueSet/observationreferencerangemeaningcodes |
| Reference Range Description | String | 0..1 | Textual description of a reference range in an observation, which may be used when a quantitative range is not appropriate for said observation. An example would be a reference value of "negative" or a list or table of "normals". |
| Target Population Code | Codeable Concept | 0..* | Uniquely specifies the target population(s) to which the reference range applies (e.g., male, female, pregnancy not delivered, American Indian, Alaska Native).
Value Set: To be developed. |
Relationships
| From class | From multiplicity | Relationship | To class | To multiplicity |
|---|---|---|---|---|
| Observation | 0..* | has (composition) | Observation Reference Range | 0..* |
| Observation Component | 0..* | has (composition) | Observation Reference Range | 0..* |
Contact us
If you have questions about this initiative, would like to be added to our stakeholder notification list or would like to participate in our consultations, please email us.
How to cite:
Canadian Institute for Health Information. Observation Reference Range. Accessed November 02, 2026.
