<?xml version="1.0" encoding="UTF-8"?>

  <!--  
 This is an example of a simple weight measurement.
  -->
<Observation xmlns="http://hl7.org/fhir">
  <id value="example"/>
  <!--   the mandatory quality flags:   -->
  <status value="final"/>
  <!--  category code is A code that classifies the general type of observation being made. This is used for searching, sorting and display purposes. -->
  <category>
    <coding>
      <system value="http://terminology.hl7.org/CodeSystem/observation-category"/>
      <code value="vital-signs"/>
      <display value="Vital Signs"/>
    </coding>
  </category>
  <category>
    <coding>
      <system value="http://loinc.org"/>
      <code value="29463-7"/>
      <!--  methodless LOINC "interoperability category" code  -->
      <display value="Body Weight"/>
    </coding>
  </category>
  <!--  
    Observations are often coded in multiple code systems.
      - LOINC provides codes of varying granularity (though not usefully more specific in this particular case) and more generic LOINCs  can be mapped to more specific codes as shown here
      - snomed provides a clinically relevant code that is usually less granular than LOINC
      - the source system provides its own code, which may be less or more granular than LOINC
    -->
  <code>
    <!--   LOINC - always recommended to have a LOINC code   -->
    <coding>
      <system value="http://loinc.org"/>
      <code value="29463-7"/>
      <display value="Body weight"/>
    </coding>
    <!--   SNOMED CT Codes - becoming more common   -->
    <coding>
      <system value="http://snomed.info/sct"/>
      <code value="27113001"/>
      <display value="Body weight"/>
    </coding>
    <!--   Also, a local code specific to the source system   -->
    <coding>
      <system value="http://acme.org/devices/clinical-codes"/>
      <code value="body-weight"/>
      <display value="Body Weight"/>
    </coding>
  </code>
  <subject>
    <reference value="Patient/example"/>
  </subject>
  <encounter>
    <reference value="Encounter/example"/>
  </encounter>
  <effectiveDateTime value="2016-03-28"/>
  <!--   In FHIR, units may be represented twice. Once in the
    agreed human representation, and once in a coded form.
    Both is best, since it's not always possible to infer
    one from the other in code.

    When a computable unit is provided, UCUM (http://unitsofmeasure.org)
    is always preferred, but it doesn't provide notional units (such as
    "tablet"), etc. For these, something else is required (e.g. SNOMED CT)
     -->
  <valueQuantity>
    <value value="185"/>
    <unit value="lbs"/>
    <system value="http://unitsofmeasure.org"/>
    <code value="[lb_av]"/>
  </valueQuantity>
  <component>
    <code>
      <coding>
        <system value="http://loinc.org"/>
        <code value="8361-8"/>
        <display value="Body position with respect to gravity"/>
      </coding>
    </code>
    <valueCodeableConcept>
      <coding>
        <system value="http://snomed.info/sct"/>
        <code value="10904000"/>
        <display value="Standing position"/>
      </coding>
    </valueCodeableConcept>
  </component>
</Observation>