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

<Observation xmlns="http://hl7.org/fhir">
  <id value="f205"/>
  <identifier>
    <system value="https://intranet.aumc.nl/labvalues"/>
    <!--   Does not exist   -->
    <value value="1304-03720-eGFR"/>
  </identifier>
  <!--   eGFR was measured on April fourth   -->
  <status value="final"/>
  <code>
    <!--   Kind of observation = eGFR   -->
    <coding>
      <system value="http://loinc.org"/>
      <code value="33914-3"/>
      <display value="Glomerular filtration rate [Volume Rate/Area] in Serum or Plasma by Creatinine-based formula (MDRD)/1.73 sq M"/>
    </coding>
  </code>
  <subject>
    <reference value="Patient/f201"/>
    <display value="Roel"/>
  </subject>
  <issued value="2013-04-04T14:34:00+01:00"/>
  <performer>
    <reference value="Practitioner/f202"/>
    <display value="Luigi Maas"/>
  </performer>
  <!--  no value element since have only component values and unable to interpret results needs clinical interpretation  -->
  <interpretation>
    <text value="interpretation of results should be assigned based upon the level of kindey function"/>
  </interpretation>
  <note>
    <text value="GFR estimating equations developed by the Modification of Diet in Renal Disease (MDRD) Study Group and the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI)...."/>
  </note>
  <!--   The observation is complete   -->
  <!--   No reliability concerns   -->
  <method>
    <!--   Method was MDRD   -->
    <coding>
      <system value="http://snomed.info/sct"/>
      <code value="702668005"/>
      <display value="MDRD"/>
    </coding>
  </method>
  <!--   The MDRD equation does require race (African American or non-African American), which also might not be readily available. For this reason, eGFR values for both African Americans and non-African Americans are reported. so use component elements here  -->
  <component>
    <code>
      <!--   Kind of observation = eGFR for AA   -->
      <coding>
        <system value="http://loinc.org"/>
        <code value="48643-1"/>
        <display value="Glomerular filtration rate [Volume Rate/Area] in Serum, Plasma or Blood by Creatinine-based formula (MDRD)/1.73 sq M among black population"/>
      </coding>
    </code>
    <valueQuantity>
      <!--   eGFR=54mL/min/1.73m2   -->
      <value value="60"/>
      <comparator value="&gt;"/>
      <unit value="mL/min/1.73m2"/>
      <system value="http://unitsofmeasure.org"/>
      <code value="mL/min/{1.73_m2}"/>
    </valueQuantity>
    <referenceRange>
      <low>
        <value value="60"/>
        <unit value="mL/min/1.73m2"/>
        <system value="http://unitsofmeasure.org"/>
        <code value="mL/min/{1.73_m2}"/>
      </low>
      <appliesTo>
        <text value="non-black/african-american"/>
      </appliesTo>
      <age>
        <low>
          <value value="18"/>
          <unit value="yrs"/>
          <system value="http://unitsofmeasure.org"/>
          <code value="a"/>
        </low>
      </age>
    </referenceRange>
  </component>
  <component>
    <code>
      <!--   Kind of observation = eGFR for non AA   -->
      <coding>
        <system value="http://loinc.org"/>
        <code value="48642-3"/>
        <display value="GFR/BSA pr.non blk SerPlBld MDRD-ArV"/>
      </coding>
    </code>
    <valueQuantity>
      <!--   eGFR=54mL/min/1.73m2   -->
      <value value="60"/>
      <unit value="mL/min/1.73m2"/>
      <system value="http://unitsofmeasure.org"/>
      <code value="mL/min/{1.73_m2}"/>
    </valueQuantity>
    <referenceRange>
      <low>
        <value value="60"/>
        <unit value="mL/min/1.73m2"/>
        <system value="http://unitsofmeasure.org"/>
        <code value="mL/min/{1.73_m2}"/>
      </low>
      <age>
        <low>
          <value value="18"/>
          <unit value="yrs"/>
          <system value="http://unitsofmeasure.org"/>
          <code value="a"/>
        </low>
      </age>
    </referenceRange>
  </component>
</Observation>