Federated Self-Paced Learning Signals Enhanced LLM Training For Long-Context Adverse Drug Events Detection In Clinical Text

Authors

  • Poonam Kashtriya National Institute of Technology, Hamirpur, India
  • Pardeep Singh National Institute of Technology, Hamirpur, India

DOI:

https://doi.org/10.29284/538mtv24

Keywords:

Biomedical Informatics, Federated Learning, LLM, Self-Paced Learning, Bioinformatics, Adverse Drug Events, EHR, PEFT, Qwen 2.5

Abstract

Detecting adverse drug events (ADEs) in free-text clinical notes is important for patient safety yet challenging because mentions of ADEs are rare and many paragraphs contain language that can be confusing, for example negated or historical statements. We study paragraph-level ADE detection with a compact large language model, Qwen2.5-1.5B, trained using self-paced learning that starts with clearer, easier paragraphs and gradually introduces harder, more ambiguous ones. We build a paragraph-level dataset from n2c2 notes and simulate a multi-hospital setting by partitioning the corpus into non-identical silos for federated learning. The model fine-tunes only LoRA adapters while keeping the backbone frozen, which keeps memory and communication low. In centralised training the system reaches 88.92 macro-F1 on n2c2, about 17 points higher than the strongest prior transformer baseline in our compilation. In federated training across five silos the main schedule achieves 88.59 macro-F1 with client participation 0.60 over 50 rounds, and a compute-capped schedule with 20 rounds and two local epochs attains 88.41 macro-F1. A no-differential-privacy ablation reaches 88.68 macro-F1. Communication is modest, with approximately 12.1 MB uplink and 10.9 MB downlink per participating round, which totals about 0.69 GB per client for the main schedule and 0.27 GB for the compute-capped schedule. Client-level Gaussian noise with σ≈0.41 yields ε≈2.4 at δ=10⁻⁶ in our accounting. These results show that a small LLM with self-paced learning delivers strong ADE screening and that the gains carry over to a federated setting with practical bandwidth and privacy budgets.

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Published

2025-12-10

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Section

Articles

How to Cite

[1]
P. Kashtriya and P. Singh, “Federated Self-Paced Learning Signals Enhanced LLM Training For Long-Context Adverse Drug Events Detection In Clinical Text”, IJASIS, pp. 96–109, Dec. 2025, doi: 10.29284/538mtv24.

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