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SMASH: A Data-driven Informatics Method to Assist Experts in Characterizing Semantic Heterogeneity among Data
William Brown1, Chunhua Weng2, David K Vawdrey3
1Department of Biomedical Informatics, Columbia University, New York, NY; HIV Center for Clinical and Behavioral Studies, NY State Psychiatric Institute & Columbia University, New York, NY.
Semantic heterogeneity (SH) in healthcare data hinders interoperability. A new method, SMASH, combined with expert review, effectively identified SH in HIV data, revealing most issues stem from differing terms for the same concept.
Area of Science:
- Health Informatics
- Data Science
- Biomedical Data Standards
Background:
- Semantic heterogeneity (SH) poses significant challenges to data interoperability and integration within healthcare systems.
- Accurate assessment of SH is crucial for developing effective strategies to improve data consistency and usability.
- HIV-associated data elements (DEs) present a complex case for assessing SH due to variations in terminology and meaning.
Purpose of the Study:
- To assess semantic heterogeneity among HIV-associated data elements using both expert-based and data-driven approaches.
- To introduce and evaluate a novel method, String Metric-assisted Assessment of Semantic Heterogeneity (SMASH), for identifying SH.
- To compare the effectiveness of expert review and data-driven methods in identifying and characterizing SH.
Main Methods:
- Extracted eight data dictionaries from Clinicaltrials.gov to create a comprehensive inventory of HIV-associated data elements (DEs).
- Developed and applied the SMASH method to vectorize DEs and identify semantic similarities and differences between studies.
- Utilized an HIV expert to assess semantic equivalence of data element pairs and contextualize usage.
Main Results:
- Out of 1,175 data element pairs analyzed, 1,048 (87%) exhibited semantic heterogeneity, while 127 (13%) were homogeneous.
- The majority of heterogeneous pairs (97%) were characterized by semantically equivalent but syntactically different terms (e.g., 'HIV-positive' vs. 'HIV+' vs. 'Seropositive').
- SMASH effectively aided in the identification of SH, particularly highlighting semantically equivalent/syntactically different DEs.
Conclusions:
- Combining expert-based and data-driven methods, including the novel SMASH approach, is highly effective for assessing semantic heterogeneity in healthcare data.
- Semantic equivalence with syntactic differences represents the most common form of SH in HIV-associated data.
- The study recommends the adoption of complementary expert-driven and data-driven solutions to resolve semantic heterogeneity issues.
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