Intro

• Ontology: LOINC
• Key Challenges

LOINC

• Logical Observation Identifiers Names and Codes (loinc.org)
• Ontology for labs and clinical measurements
  • Laboratory LOINC
  • Clinical LOINC
• Goal is interoperability
• Uniquely identify every possible lab

LOINC

• Component (analyte): substance or entity measured or observed
• Property: e.g., mass concentration, numeric fraction
• Time: point in time
• Specimen (system): e.g., blood, cerebrospinal fluid
• Scale: e.g., qualitative, quantitative, ordinal, nominal
• Method: optional, procedure used to make observation

LOINC - CBC

LOINC - Creatinine

LOINC - PSA

LOINC - Prostate

Lab Lifecycle

Key Challenges

• Same lab, different name
• Same test, different body fluid
• Different labs, different reference ranges
• per-hospital variation in devices used
• Consistency in units and normal ranges
• Calculated values that require other clinical data (eGFR)
• Lack of good groupers

Key Challenges

• Erroneous results
• Results change over time
  • micro: may be negative at first, but subsequently positive
  • erroneous corrected

Key Lab Tables

• LabDim: Info about the laboratories themselves
• LabComponentDim: info about the lab tests
• LabTestFact: data about the test itself
• LabComponentResultFact: actual test results
• LabTestComponentResultMappingFact: linking LabTestFact to LabComponentResultFact