Critical Challenges and Research Gaps in Blockchain-Based Federated Learning for Healthcare: A Comprehensive Review

Saad Ahmed Sazan; Mahdi Miraz; Iftekhar Salam

doi:10.35377/saucis...1827765

Critical Challenges and Research Gaps in Blockchain-Based Federated Learning for Healthcare: A Comprehensive Review

Abstract

The incorporation of federated learning (FL) and blockchain has appeared as a transformative approach for privacy-preserving, decentralised healthcare data sharing. This literature review examines recent advancements in FL-blockchain frameworks applied to healthcare, focusing on critical challenges including data privacy, security, collaboration barriers, centralisation issues and scalability concerns. The findings reveal that blockchain enhances data integrity, access control and trust, while FL enables collaborative model training without sharing raw patient data. Despite these advantages, significant challenges persist such as vulnerabilities to adversarial attacks, regulatory compliance gaps with General Data Protection Regulation (GDPR) and Health Insurance Portability and Accountability Act (HIPAA), handling heterogeneous, non-independent, and identically distributed (non-IID) medical datasets that degrade model performance. The review highlights emerging solutions including secure multi-party computation, smart contract-based aggregation, and incentive mechanisms, while emphasizing the need for future research to develop regulatory-aligned, scalable, and anomaly-resilient FL-blockchain architectures specific to healthcare. Addressing these challenges is essential to establish a trustworthy, efficient, and legally compliant AI-driven healthcare systems.

Keywords

Supporting Institution

Xiamen University Malaysia

Project Number

XMUMRF/2021‐C8/IECE/0025 and XMUMRF/2022‐C10/IECE/0043

References

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Details

Primary Language

English

Subjects

Artificial Intelligence (Other)

Journal Section

Review

Authors

Saad Ahmed Sazan
0009-0000-7669-5919
Malaysia

Mahdi Miraz ^*
0000-0002-6795-7048
Malaysia

Iftekhar Salam
0000-0003-1395-4623
Malaysia

Early Pub Date

June 25, 2026

Publication Date

June 30, 2026

Submission Date

December 3, 2025

Acceptance Date

March 6, 2026

Published in Issue

Year 2026 Volume: 9 Number: 3

DOI

https://doi.org/10.35377/saucis...1827765

IZ

https://izlik.org/JA55SL38TG

Cite

RIS / Bibtex

APA

Sazan, S. A., Miraz, M., & Salam, I. (2026). Critical Challenges and Research Gaps in Blockchain-Based Federated Learning for Healthcare: A Comprehensive Review. Sakarya University Journal of Computer and Information Sciences, 9(3), 995-1003. https://doi.org/10.35377/saucis...1827765

AMA

1.Sazan SA, Miraz M, Salam I. Critical Challenges and Research Gaps in Blockchain-Based Federated Learning for Healthcare: A Comprehensive Review. SAUCIS. 2026;9(3):995-1003. doi:10.35377/saucis.1827765

Chicago

Sazan, Saad Ahmed, Mahdi Miraz, and Iftekhar Salam. 2026. “Critical Challenges and Research Gaps in Blockchain-Based Federated Learning for Healthcare: A Comprehensive Review”. Sakarya University Journal of Computer and Information Sciences 9 (3): 995-1003. https://doi.org/10.35377/saucis. 1827765.

EndNote

Sazan SA, Miraz M, Salam I (June 1, 2026) Critical Challenges and Research Gaps in Blockchain-Based Federated Learning for Healthcare: A Comprehensive Review. Sakarya University Journal of Computer and Information Sciences 9 3 995–1003.

IEEE

[1]S. A. Sazan, M. Miraz, and I. Salam, “Critical Challenges and Research Gaps in Blockchain-Based Federated Learning for Healthcare: A Comprehensive Review”, SAUCIS, vol. 9, no. 3, pp. 995–1003, June 2026, doi: 10.35377/saucis...1827765.

ISNAD

Sazan, Saad Ahmed - Miraz, Mahdi - Salam, Iftekhar. “Critical Challenges and Research Gaps in Blockchain-Based Federated Learning for Healthcare: A Comprehensive Review”. Sakarya University Journal of Computer and Information Sciences 9/3 (June 1, 2026): 995-1003. https://doi.org/10.35377/saucis. 1827765.

JAMA

1.Sazan SA, Miraz M, Salam I. Critical Challenges and Research Gaps in Blockchain-Based Federated Learning for Healthcare: A Comprehensive Review. SAUCIS. 2026;9:995–1003.

MLA

Sazan, Saad Ahmed, et al. “Critical Challenges and Research Gaps in Blockchain-Based Federated Learning for Healthcare: A Comprehensive Review”. Sakarya University Journal of Computer and Information Sciences, vol. 9, no. 3, June 2026, pp. 995-1003, doi:10.35377/saucis. 1827765.

Vancouver

1.Saad Ahmed Sazan, Mahdi Miraz, Iftekhar Salam. Critical Challenges and Research Gaps in Blockchain-Based Federated Learning for Healthcare: A Comprehensive Review. SAUCIS. 2026 Jun. 1;9(3):995-1003. doi:10.35377/saucis. 1827765