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arXiv · 2508.02556

Automated SNOMED CT Concept Annotation in Clinical Text Using Bi-GRU Neural Networks

Ali Noori·Pratik Devkota·Somya Mohanty·Prashanti Manda
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Abstract

Automated annotation of clinical text with standardized medical concepts is critical for enabling structured data extraction and decision support. SNOMED CT provides a rich ontology for labeling clinical entities, but manual annotation is labor-intensive and impractical at scale. This study introduces a neural sequence labeling approach for SNOMED CT concept recognition using a Bidirectional GRU model. Leveraging a subset of MIMIC-IV, we preprocess text with domain-adapted SpaCy and SciBERT-based tokenization, segmenting sentences into overlapping 19-token chunks enriched with contextual, syntactic, and morphological features. The Bi-GRU model assigns IOB tags to identify concept spans and achieves strong performance with a 90 percent F1-score on the validation set. These results surpass traditional rule-based systems and match or exceed existing neural models. Qualitative analysis shows effective handling of ambiguous terms and misspellings. Our findings highlight that lightweight RNN-based architectures can deliver high-quality clinical concept annotation with significantly lower computational cost than transformer-based models, making them well-suited for real-world deployment.

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Ali Noori, Pratik Devkota, Somya Mohanty, Prashanti Manda. 2025-08-04. Automated SNOMED CT Concept Annotation in Clinical Text Using Bi-GRU Neural Networks. https://arxiv.org/abs/2508.02556

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