<Observation xmlns="http://hl7.org/fhir">
    <id value="demo-vitalsign-bw-5" />
    <status value="final" />
    <category>
        <coding>
            <system value="http://hl7.org/fhir/observation-category" />
            <code value="vital-signs" />
        </coding>
    </category>
    <code>
        <coding>
            <system value="http://loinc.org" />
            <code value="29463-7" />
            <display value="Body weight" />
        </coding>
    </code>
    <subject>
        <reference value="Patient/demo-patient-1" />
    </subject>
    <effectiveDateTime value="2018-03-12" />
    <valueQuantity>
        <value value="69.3" />
        <system value="http://unitsofmeasure.org" />
        <code value="kg" />
    </valueQuantity>
</Observation>