This value set includes codes based on the following rules:

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

  Code	Display
  119297000	Blood
  258564008	Buccal smear
  69640009	Crust
  119342007	Saliva
  472875007	Vesicular Swab
  77601007	Tissue
  122575003	Urine
  128306009	Cataract

• Include these codes as defined in urn:oid:2.16.840.1.114222.4.5.274 version 20200526

  Code	Display
  PHC228	Macular Scraping

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

  Code	Display
  OTH	Other
  UNK	unknown