This value set includes codes based on the following rules:

• Include these codes as defined in http://terminology.hl7.org/CodeSystem/v2-0532 version HL7 v2.5

  Code	Display
  N	No
  Y	Yes

• Include these codes as defined in http://snomed.info/sct version http://snomed.info/sct/731000124108/version/20200901

  Code	Display
  373121007	Test not done

• Include these codes as defined in http://terminology.hl7.org/CodeSystem/v3-NullFlavor version 20090501

  Code	Display
  UNK	Unknown