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Validation of a Major and Clinically Relevant Nonmajor Bleeding Phenotyping Algorithm on Electronic Health Records
Aaron Jun Yi Yap1, Desmond Chun Hwee Teo1, Pei San Ang1
1Vigilance & Compliance Branch, Health Products Regulation Group, Health Sciences Authority, Singapore.
We developed algorithms to identify major bleeding events in electronic health records. These algorithms, using hemoglobin patterns and diagnosis codes, offer higher sensitivity than diagnosis codes alone for epidemiological studies.
Area of Science:
- Medical Informatics
- Epidemiology
- Health Data Science
Background:
- Bleeding events are critical health outcomes in epidemiological research.
- Accurate identification of bleeding in electronic healthcare data is essential for population studies.
Purpose of the Study:
- To develop and validate rule-based algorithms for identifying major bleeding and all clinically relevant bleeding (CRB) in real-world electronic healthcare data.
- To compare algorithm performance against diagnosis codes alone.
Main Methods:
- Utilized a random sample of 1630 inpatient admissions from Singapore public healthcare institutions (2019-2020).
- Ascertained major bleeding and CRB through chart review by two annotators.
- Developed and validated sensitivity- and positive predictive value (PPV)-optimized algorithms combining hemoglobin test patterns and diagnosis codes.
Main Results:
- Diagnosis codes alone showed low sensitivity (0.16 for major bleeding, 0.24 for CRB) but high specificity and PPV (>0.97).
- Sensitivity-optimized algorithm for major bleeding achieved high sensitivity (0.94) and NPV (1.00) but lower PPV (0.34).
- PPV-optimized algorithm for major bleeding improved specificity (0.96) and PPV (0.52) with minimal impact on sensitivity (0.88).
- Algorithms for CRB events demonstrated lower sensitivities (0.50-0.56).
Conclusions:
- Diagnosis codes alone are insufficient for accurately identifying major bleeding events in electronic health records.
- Developed major bleeding algorithms demonstrate high sensitivity, enabling better ascertainment of bleeding events in large populations.
- These algorithms are valuable tools for epidemiological studies requiring accurate bleeding event identification.
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