LOINC Ontology Content Adjustments

This section last updated: 2025-02-18 (4 days ago)

The list below contains all the individual changes that LOINC terminology applied in order to support computer readability of LOINC Parts, to apply post-coordination, and to clean up where needed to avoid redundancy, duplication, and consistency in expression or meaning.

Changes from previous releases:

• There are 2 similar systems in LOINC: 1. Respiratory system, 2. Respiratory specimen. Due to an applied logic, the display in the System axis for (1) is Respiratory (adjective) without specification of sample, specimen, or other specific noun, while (2) is displayed fully as Respiratory specimen. Therefore we replaced "Respiratory" with "Respiratory system specimen" (LOINC v2.75).
  • Note: As result of this change, LOINC parts “Respiratory.lower” and “Respiratory.upper” were updated to “Respiratory System Specimen.lower” and “Respiratory System Specimen.upper” respectively (LOINC v2.77).
• Allergy codes IgE with RAST in the Component (post-coordinated concept). We added RAST as Method part, and removed it from Component (LOINC v2.75).

Changes to LOINC Parts that are included in Release 2.79. You will find all the details in the CSV accessory files related to the release:

• The understanding is that the word "Identified" has the same meaning as Property: "PRID", its presence in the component is redundant to the property. Therefore we remove "identified" from the Component.
• Component where the description is property like as in Color, Appearance, Osmolality have changed to Component: Observation, and Property: Color, or Appearance, or Osmolality, and so forth, keeping the challenge and/ or adjustment in the Component description.
• eGFR measurement representation in LOINC has changed:
  • Component: Glomerular filtration rate, Method: .../1.73 sq.M among non-black population or …/1.73 sq.M among black population, and similarly extended to other part of the Component descriptions.
• Polymorphonuclear cells is an old term, and not in use anymore. Therefore we replaced polymorphonuclear cells with Granulocytes.
• Pre-coordination of the component with Property: Mean concentration; the decision was to post coordinate and separate current Component to Component and Property;
• Removing NOS from Component Part
• Replacing the component description with the scientific name;
• Screen should be omitted from Component. It should be in Method.
• Specimen source is more of System, not a Component. hence we removed Source from the expression to be more appropriate of a Component description.
• This is a specific fraction case where the denominator is percentage or /100. Because the logic is that the fraction is captured by Property: NFr (Numeric Fraction), and by Unit: % (percentile), therefore, it is redundant to include "100" in the component, and the fraction is represented without prefix "100" in the denominator.
• Hematocrit as a Component is not an expressive description for a ratio. Hematocrit is kept as a synonym, and the actual component is expressed as: Erythrocyte/Specimen.