Issues in mapping LOINC laboratory tests to SNOMED CT

Area of Science:

• Medical Informatics
• Clinical Terminology
• Health Data Standards

Background:

• Clinical terminologies like SNOMED CT and LOINC have overlapping domains, particularly for laboratory procedures.
• The Unified Medical Language System (UMLS) is used to integrate different terminologies, but LOINC integration remains suboptimal.
• Existing methods for mapping between SNOMED CT and LOINC face challenges due to differences in granularity and concept definition.

Purpose of the Study:

• To investigate the feasibility and challenges of mapping laboratory test concepts from LOINC to SNOMED CT.
• To identify limitations in SNOMED CT that hinder comprehensive integration with LOINC.
• To improve the interoperability of clinical and laboratory terminologies.

Main Methods:

• Mapping of laboratory test concepts from LOINC to pre-coordinated SNOMED CT concepts.
• Utilizing shared relations between concepts as the basis for mapping.
• Analysis of mapping success rates and reasons for mapping failures.

Main Results:

• A significant portion of LOINC codes could be mapped to SNOMED CT concepts.
• Due to LOINC's finer granularity, multiple LOINC codes often mapped to a single SNOMED CT concept.
• A substantial number of LOINC codes could not be mapped due to underspecified SNOMED CT definitions and a lack of fine-grained concepts.

Conclusions:

• Direct mapping of LOINC to SNOMED CT is limited by SNOMED CT's structural and definitional characteristics.
• Enhancements to SNOMED CT, such as increased granularity and pre-coordinated concepts, are needed for better integration.
• Improved mapping strategies and terminology development are crucial for seamless clinical and laboratory data exchange.