Online Narrative and Codified feature Search Engine (ONCE)

What is it?

For a target disease with its name as input, the ONCE system can generate a list of related EHR features:
  • Narrative features:
    • Standardized clinical concepts represented by concept unique identifiers (CUIs) according to the unified medical language system (UMLS)
  • Codified features:
    • PheCodes mapped from ICD codes;
    • Ingredient-level RxNorm codes mapped from Medication prescriptions;
    • Grouped CPT procedure codes according to the Clinical Classifications Software;
    • LOINC codes mapped from laboratory tests.
The output of ONCE can be used as input features for predictive modeling of a target disease phenotype (see a paired phenotyping app - KOMAP ;

Why does it work?

  • Representative learning: The key component that powers the ONCE feature selection engine is the semantic representations of all EHR codified and NLP concepts, trained via multi-source knowledge graph representation learning.
  • Online article knowledge: To identify an initial set of clinical concepts important to a target disease, the ONCE system additionally leverages a large knowledge base of medical articles that describe the relatedness between narrative features and the disease at a higher level. The current article corpus comprises data from seven online sources including Wikipedia, Medscape, and Merck Manuals.
  • A composite feature score: The final ONCE selection criteria are based on a composite score that integrates information on:
    • Relatedness of a candidate concept to the target concept as quantified by the semantic embeddings;
    • Frequency of the candidate concept in the EHR;
    • Weighted frequency of the concept in the disease-related knowledge source articles.

How does it work?

  • Step 1: Type in your disease of interest;
  • Step 2: Choose the main CUI(s) and the main PheCode corresponding to the disease. ONCE already select several candidates for you. You can select multiple main CUIs and a single main PheCode among them.
  • Step 3: Just click the "Search" button and you are ready to go!