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Leveraging Hybrid Natural Language Processing Techniques for Large-Scale Pulmonary Embolism Identification.
Syed Moin Hassan1, Ruben Mylvaganam2, Tekle Didebulidze3
1Division of Pulmonary and Critical Care, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA.
A hybrid natural language processing (NLP) approach accurately identifies pulmonary embolism (PE) in radiology reports. This method combines machine learning and rules, improving diagnostic efficiency and clinical surveillance.
Area of Science:
- Medical Informatics
- Natural Language Processing
- Health Data Analysis
Background:
- Pulmonary embolism (PE) diagnosis and management remain challenging despite medical advancements.
- Large-scale electronic health record analysis is crucial for understanding PE pathophysiology and optimizing treatment.
- Hybrid natural language processing (NLP) offers a promising methodology for this analysis.
Purpose of the Study:
- To develop and validate a hybrid NLP pipeline for accurate PE case identification.
- The pipeline combines machine learning (ML) and rule-based techniques.
- The goal is to process large-scale radiology report datasets.
Main Methods:
- A ML algorithm was trained on 1,040 computed tomography pulmonary angiogram reports.
- The pipeline was validated on 49,611 radiology reports from the Mass General Brigham (MGB) healthcare system.
- Performance metrics included accuracy, sensitivity, specificity, PPV, and NPV.
Main Results:
- The initial ML model achieved 91% accuracy on test data.
- Deployment on the MGB dataset showed 85% accuracy, which improved to 94.8% after applying the rule-based algorithm.
- The final hybrid model demonstrated high sensitivity (96.4%) and specificity (93.2%) on the MGB dataset.
Conclusions:
- The hybrid NLP approach requires less training data than pure ML models.
- It demonstrated high performance across diverse healthcare settings.
- This pipeline can efficiently identify PE cases for research and clinical surveillance.
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