description: To promote interoperability and adoption through common implementation, this profile sets minimum expectations for the Observation resource to record, search, and fetch head circumference observations with a standard LOINC code and UCUM units of measure. It is based on the US Core Vital Signs Profile and identifies which *additional* core elements, extensions, vocabularies, and value sets **SHALL** be present and constrains the way the elements are used when using the profile. It provides the floor for standards development for specific use cases.
package_name: hl7.fhir.us.core
derivation: constraint
name: USCoreHeadCircumferenceProfile
type: Observation
elements:
  code:
    type: CodeableConcept
    short: (USCDI) Head Circumference
    mustSupport: true
    pattern:
      type: CodeableConcept
      value:
        coding:
        - {code: 9843-4, system: 'http://loinc.org'}
    index: 0
  valueQuantity:
    short: (USCDI) Vital Signs Value
    mustSupport: true
    index: 1
    elements:
      value: {type: decimal, short: (USCDI) Numerical value (with implicit precision), mustSupport: true, index: 2}
      unit: {type: string, short: (USCDI) Unit representation, mustSupport: true, index: 3}
      system:
        short: (USCDI) System that defines coded unit form
        pattern: {type: Uri, value: 'http://unitsofmeasure.org'}
        type: uri
        mustSupport: true
        index: 4
      code:
        short: (USCDI) Coded responses from the common UCUM units for vital signs value set.
        type: code
        mustSupport: true
        binding: {strength: required, valueSet: 'http://hl7.org/fhir/ValueSet/ucum-bodylength|4.0.1'}
        index: 5
    required: [value, unit, system, code]
package_version: 6.1.0
class: profile
kind: resource
url: http://hl7.org/fhir/us/core/StructureDefinition/us-core-head-circumference
base: http://hl7.org/fhir/us/core/StructureDefinition/us-core-vital-signs
version: 6.1.0