Attention-Weighted Retrieval-Augmented Data Engineering for ADR Severity Classification

David Guo, Nishant Vishwamitra, Kim-Kwang Raymond Choo


Abstract
Adverse drug reaction (ADR) severity prediction is a key task in pharmacovigilance and post-market drug safety surveillance, but is of- ten challenged by noisy and heterogeneous clinical data. We propose a retrieval-augmented learning framework that leverages historical FAERS reports to construct evidence-enriched training instances for ADR severity prediction. Each ADR query, including patient demographics, drug exposure, and indications, is encoded using a fine-tuned BGE-M3 embedding model. We retrieve the top five relevant cases using BM25 lexical search and the top five semantically similar cases using dense vector search, and fuse them via an attention-based aggregation mechanism to produce retrieval-aware representations. These representations are evaluated using machine learning, deep learning, transformer, and fine-tuned large language model approaches for binary severity prediction. Results show that a tree-based ensemble achieves the best performance with an AUC of 82.3%, outperforming the strongest deep learning baseline by 2.3 percentage points and fine-tuned LLMs by 17 percentage points. Overall, the findings demonstrate that retrieval-enhanced data preprocessing can improve representation quality for ADR severity prediction, while the proposed upstream data engineering approach enables classical ensemble methods to remain highly effective for large-scale pharmacovigilance risk prediction.
Anthology ID:
2026.emnlp-industry.131
Volume:
Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing: Industry Track
Month:
October
Year:
2026
Address:
Budapest, Hungary
Editors:
Pepa Atanasova, Gholamreza Haffari, Minghan Wang
Venue:
EMNLP
SIG:
SIGDAT
Publisher:
Association for Computational Linguistics
Note:
Pages:
2234–2243
Language:
URL:
https://aclanthology.org/2026.emnlp-industry.131/
DOI:
Bibkey:
Cite (ACL):
David Guo, Nishant Vishwamitra, and Kim-Kwang Raymond Choo. 2026. Attention-Weighted Retrieval-Augmented Data Engineering for ADR Severity Classification. In Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing: Industry Track, pages 2234–2243, Budapest, Hungary. Association for Computational Linguistics.
Cite (Informal):
Attention-Weighted Retrieval-Augmented Data Engineering for ADR Severity Classification (Guo et al., EMNLP 2026)
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PDF:
https://aclanthology.org/2026.emnlp-industry.131.pdf