FaMeSumm: Investigating and Improving Faithfulness of Medical Summarization

Nan Zhang, Yusen Zhang, Wu Guo, Prasenjit Mitra, Rui Zhang


Abstract
Summaries of medical text shall be faithful by being consistent and factual with source inputs, which is an important but understudied topic for safety and efficiency in healthcare. In this paper, we investigate and improve faithfulness in summarization on a broad range of medical summarization tasks. Our investigation reveals that current summarization models often produce unfaithful outputs for medical input text. We then introduce FaMeSumm, a framework to improve faithfulness by fine-tuning pre-trained language models based on medical knowledge. FaMeSumm performs contrastive learning on designed sets of faithful and unfaithful summaries, and it incorporates medical terms and their contexts to encourage faithful generation of medical terms. We conduct comprehensive experiments on three datasets in two languages: health question and radiology report summarization datasets in English, and a patient-doctor dialogue dataset in Chinese. Results demonstrate that FaMeSumm is flexible and effective by delivering consistent improvements over mainstream language models such as BART, T5, mT5, and PEGASUS, yielding state-of-the-art performances on metrics for faithfulness and general quality. Human evaluation by doctors also shows that FaMeSumm generates more faithful outputs. Our code is available at https://github.com/psunlpgroup/FaMeSumm.
Anthology ID:
2023.emnlp-main.673
Volume:
Proceedings of the 2023 Conference on Empirical Methods in Natural Language Processing
Month:
December
Year:
2023
Address:
Singapore
Editors:
Houda Bouamor, Juan Pino, Kalika Bali
Venue:
EMNLP
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
10915–10931
Language:
URL:
https://aclanthology.org/2023.emnlp-main.673
DOI:
10.18653/v1/2023.emnlp-main.673
Bibkey:
Cite (ACL):
Nan Zhang, Yusen Zhang, Wu Guo, Prasenjit Mitra, and Rui Zhang. 2023. FaMeSumm: Investigating and Improving Faithfulness of Medical Summarization. In Proceedings of the 2023 Conference on Empirical Methods in Natural Language Processing, pages 10915–10931, Singapore. Association for Computational Linguistics.
Cite (Informal):
FaMeSumm: Investigating and Improving Faithfulness of Medical Summarization (Zhang et al., EMNLP 2023)
Copy Citation:
PDF:
https://aclanthology.org/2023.emnlp-main.673.pdf
Video:
 https://aclanthology.org/2023.emnlp-main.673.mp4