LTRC-Medicom at MEDIQA-SYNUR 2026: Schema-Guided Clinical Information Extraction with Hybrid Clustering-SFT-Verification

Pasumarthy Deepak, Sushvin Marimuthu, Parameswari Krishnamurthy


Abstract
Extracting structured clinical data from unstructured patient transcripts is challenging due to large target schemas and inherent linguistic ambiguity. We address the extraction of 193 heterogeneous clinical attributes from nursing notes and clinician–patient dialogues, and demonstrate that zero-shot large language models (LLMs) are ineffective in this setting, achieving an F1 score below 0.15 due to context window saturation and hallucination. We propose a four-stage framework that combines semantic schema clustering, role-based chain-of-thought prompting, supervised fine-tuning of Llama-3.1-8B, and transcript-verified post-processing. Our approach achieves an F1 score of 0.66, representing a 4.4x improvement over the baseline, by balancing high recall from generative models with high precision from verification. These results highlight the effectiveness of hybrid pipelines for high-stakes clinical information extraction.
Anthology ID:
2026.clinicalnlp-1.25
Volume:
Proceedings of the 8th Workshop on Clinical Natural Language Processing (Clinical NLP) @ LREC 2026
Month:
May
Year:
2026
Address:
Palma, Mallorca (Spain)
Editors:
Asma Ben Abacha, Steven Bethard, Danielle Bitterman, Tristan Naumann, Kirk Roberts
Venues:
ClinicalNLP | WS
SIG:
Publisher:
ELRA Language Resources Association (ELRA)
Note:
Pages:
228–234
Language:
External URL:
https://lrec.elra.info/lrec2026-ws-clinicalnlp-25
DOI:
10.63317/4oou5ss2efr6
Bibkey:
Cite (ACL):
Pasumarthy Deepak, Sushvin Marimuthu, and Parameswari Krishnamurthy. 2026. LTRC-Medicom at MEDIQA-SYNUR 2026: Schema-Guided Clinical Information Extraction with Hybrid Clustering-SFT-Verification. In Proceedings of the 8th Workshop on Clinical Natural Language Processing (Clinical NLP) @ LREC 2026, pages 228–234, Palma, Mallorca (Spain). ELRA Language Resources Association (ELRA).
Cite (Informal):
LTRC-Medicom at MEDIQA-SYNUR 2026: Schema-Guided Clinical Information Extraction with Hybrid Clustering-SFT-Verification (Deepak et al., ClinicalNLP 2026)
Copy Citation: