Hybrid Large Language Model and Rule-Based Framework for Automated PHI De-Identification in Clinical Notes
Research Article  ·  Published: 12 November 2025
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ICCK Transactions on Emerging Topics in Artificial Intelligence
Volume 3, Issue 1, 2026: 1-8
Research Article Open Access

Hybrid Large Language Model and Rule-Based Framework for Automated PHI De-Identification in Clinical Notes

1 School of Mathematics and Computer Science, Hezhou University, Hezhou 542899, China
* Corresponding Author: Kai Ye, [email protected]
Volume 3, Issue 1

Abstract

The growing demand for secondary use of electronic health records (EHRs) in clinical research has amplified the importance of effective de-identification of protected health information (PHI) to comply with privacy regulations such as HIPAA. Manual annotation remains error-prone, time-consuming, and inconsistent across healthcare institutions, while existing automated systems often face trade-offs between accuracy, interpretability, and computational cost. This study proposes a novel hybrid de-identification framework that integrates neural, statistical, and rule-based approaches to achieve high recall, operational efficiency, and deployment feasibility in real-world healthcare settings.

Graphical Abstract

Hybrid Large Language Model and Rule-Based Framework for Automated PHI De-Identification in Clinical Notes

Keywords

PHI de-identification clinical NLP large language models hybrid systems parameter-efficient fine-tuning (PEFT) electronic health records privacy preservation retrieval-augmented generation (RAG) rule-based NLP biomedical text processing

Data Availability Statement

Data will be made available on request.

Funding

This work was supported without any funding.

Conflicts of Interest

The author declares no conflicts of interest.

Ethical Approval and Consent to Participate

This study involves the secondary analysis of de-identified clinical notes from the Lifespan Health Network (20,000 notes) and the publicly available MIMIC-III v1.4 dataset (1,200 ICU notes), with no direct interaction with human subjects or access to identifiable private information. All data were processed in accordance with HIPAA regulations and IRB-approved data governance protocols at the originating institutions, ensuring compliance with data minimization principles. As this research qualifies as exempt secondary research using de-identified data under 45 CFR 46.104(d)(4), no additional Institutional Review Board (IRB) approval or informed consent was required.

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Cite This Article

APA Style
Ye, K. (2025). Hybrid Large Language Model and Rule-Based Framework for Automated PHI De-Identification in Clinical Notes. ICCK Transactions on Emerging Topics in Artificial Intelligence, 3(1), 1-8. https://doi.org/10.62762/TETAI.2025.518010
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TY  - JOUR
AU  - Ye, Kai
PY  - 2025
DA  - 2025/11/12
TI  - Hybrid Large Language Model and Rule-Based Framework for Automated PHI De-Identification in Clinical Notes
JO  - ICCK Transactions on Emerging Topics in Artificial Intelligence
T2  - ICCK Transactions on Emerging Topics in Artificial Intelligence
JF  - ICCK Transactions on Emerging Topics in Artificial Intelligence
VL  - 3
IS  - 1
SP  - 1
EP  - 8
DO  - 10.62762/TETAI.2025.518010
UR  - https://www.icck.org/article/abs/TETAI.2025.518010
KW  - PHI de-identification
KW  - clinical NLP
KW  - large language models
KW  - hybrid systems
KW  - parameter-efficient fine-tuning (PEFT)
KW  - electronic health records
KW  - privacy preservation
KW  - retrieval-augmented generation (RAG)
KW  - rule-based NLP
KW  - biomedical text processing
AB  - The growing demand for secondary use of electronic health records (EHRs) in clinical research has amplified the importance of effective de-identification of protected health information (PHI) to comply with privacy regulations such as HIPAA. Manual annotation remains error-prone, time-consuming, and inconsistent across healthcare institutions, while existing automated systems often face trade-offs between accuracy, interpretability, and computational cost. This study proposes a novel hybrid de-identification framework that integrates neural, statistical, and rule-based approaches to achieve high recall, operational efficiency, and deployment feasibility in real-world healthcare settings.
SN  - 3068-6652
PB  - Institute of Central Computation and Knowledge
LA  - English
ER  - 
BibTeX Format
Compatible with LaTeX, BibTeX, and other reference managers
@article{Ye2025Hybrid,
  author = {Kai Ye},
  title = {Hybrid Large Language Model and Rule-Based Framework for Automated PHI De-Identification in Clinical Notes},
  journal = {ICCK Transactions on Emerging Topics in Artificial Intelligence},
  year = {2025},
  volume = {3},
  number = {1},
  pages = {1-8},
  doi = {10.62762/TETAI.2025.518010},
  url = {https://www.icck.org/article/abs/TETAI.2025.518010},
  abstract = {The growing demand for secondary use of electronic health records (EHRs) in clinical research has amplified the importance of effective de-identification of protected health information (PHI) to comply with privacy regulations such as HIPAA. Manual annotation remains error-prone, time-consuming, and inconsistent across healthcare institutions, while existing automated systems often face trade-offs between accuracy, interpretability, and computational cost. This study proposes a novel hybrid de-identification framework that integrates neural, statistical, and rule-based approaches to achieve high recall, operational efficiency, and deployment feasibility in real-world healthcare settings.},
  keywords = {PHI de-identification, clinical NLP, large language models, hybrid systems, parameter-efficient fine-tuning (PEFT), electronic health records, privacy preservation, retrieval-augmented generation (RAG), rule-based NLP, biomedical text processing},
  issn = {3068-6652},
  publisher = {Institute of Central Computation and Knowledge}
}

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