description: This profile represents the constraint applied to the Ratio data type by the PS-ON project to use UCUM as the code system for units in a way that is informed by the constraints of the [Ratio-UV-IPS profile](http://hl7.org/fhir/uv/ips/StructureDefinition-Ratio-uv-ips.html). package_name: ca.on.oh.patient-summary derivation: constraint name: RatioPSON type: Ratio elements: numerator: {type: Quantity, mustSupport: true, index: 0} denominator: {type: Quantity, mustSupport: true, index: 1} package_version: 0.11.0 class: complex-type kind: complex-type url: http://ontariohealth.ca/fhir/StructureDefinition/ca-on-ps-profile-ratio base: http://hl7.org/fhir/StructureDefinition/Ratio version: 0.10.0