description: This profile sets minimum expectations for an Observation resource to record, search, and fetch body mass index observations with standard coding and units of measure. It is based on the [FHIR Body Mass Index (BMI) Profile](http://hl7.org/fhir/R4/bmi.html) and identifies the *additional* mandatory core elements, extensions, vocabularies and value sets that **SHALL** be present in the Observation resource when conforming to this profile. It provides the floor for standards development for specific uses cases in an Australian context.
package_name: hl7.fhir.au.core
derivation: constraint
name: AUCoreBMI
type: Observation
elements:
  status:
    pattern: {type: Code, value: final}
    index: 0
  code:
    elements:
      coding:
        array: true
        min: 2
        index: 1
        slicing:
          slices:
            snomedBMICode:
              match: {}
              schema:
                short: SNOMED CT Body Mass Index
                _required: true
                index: 2
                elements:
                  system:
                    pattern: {type: Uri, value: 'http://snomed.info/sct'}
                    index: 3
                  code:
                    pattern: {type: Code, value: '60621009'}
                    index: 4
                required: [system, code]
  subject:
    type: Reference
    refers: ['http://hl7.org.au/fhir/core/StructureDefinition/au-core-patient']
    index: 5
  encounter:
    type: Reference
    mustSupport: true
    refers: ['http://hl7.org.au/fhir/core/StructureDefinition/au-core-encounter']
    index: 6
  effective:
    short: Date, and optionally time, the observation was performed
    constraint:
      au-core-obs-01: {human: Date shall be at least to day, source: 'http://hl7.org.au/fhir/core/StructureDefinition/au-core-bmi', severity: error, expression: $this is DateTime implies $this.toString().length() >= 10}
    choices: [effectiveDateTime]
    index: 8
  effectiveDateTime:
    type: dateTime
    short: Date, and optionally time, the observation was performed
    constraint:
      au-core-obs-01: {human: Date shall be at least to day, source: 'http://hl7.org.au/fhir/core/StructureDefinition/au-core-bmi', severity: error, expression: $this is DateTime implies $this.toString().length() >= 10}
    choiceOf: effective
    index: 9
  performer:
    type: Reference
    mustSupport: true
    refers: ['http://hl7.org.au/fhir/core/StructureDefinition/au-core-organization', 'http://hl7.org.au/fhir/core/StructureDefinition/au-core-patient', 'http://hl7.org.au/fhir/core/StructureDefinition/au-core-practitioner', 'http://hl7.org.au/fhir/core/StructureDefinition/au-core-practitionerrole', 'http://hl7.org.au/fhir/core/StructureDefinition/au-core-relatedperson']
    index: 10
  value:
    short: Body mass index
    choices: []
    index: 12
    slicing:
      slices:
        valueQuantity:
          match: {}
          schema:
            short: Body mass index
            choices: []
            index: 12
package_version: 0.2.2-preview
class: profile
kind: resource
url: http://hl7.org.au/fhir/core/StructureDefinition/au-core-bmi
base: http://hl7.org/fhir/StructureDefinition/bmi
version: 0.2.2-preview