Privacy-Preserving Vertical Split Learning for Healthcare AI with Prototype-Based Anomaly Detection Against Data Poisoning

Authors

  • Dan Xue Department of Computer Science, University of Alabama at Birmingham, Birmingham, AL, USA.
  • Niklas Barnett Department of Computer Science and Engineering, University at Buffalo, Buffalo, NY, USA.

Keywords:

vertical split learning, privacy-preserving machine learning, healthcare AI, anomaly detection, data poisoning, prototype learning, federated learning, security, governance

Abstract

The integration of artificial intelligence into healthcare systems promises transformative improvements in diagnostics, treatment personalization, and operational efficiency, yet it simultaneously amplifies concerns regarding patient data privacy and the integrity of learning pipelines. Vertical split learning has emerged as a compelling paradigm that enables multiple healthcare institutions to collaboratively train deep neural networks without sharing raw feature-level data, thereby preserving confidentiality while leveraging complementary data modalities. However, the distributed nature of vertical split learning introduces new attack surfaces, particularly data poisoning and backdoor attacks that can compromise model behavior without violating privacy boundaries. This paper presents a comprehensive system-level analysis of a privacy-preserving vertical split learning framework augmented with prototype-based anomaly detection to counter data poisoning. We examine architectural trade-offs between privacy guarantees, communication overhead, and model accuracy, and we discuss how prototype-based mechanisms, which rely on learning compact class representations, can detect anomalous updates or poisoned samples at the cut layer during split learning. The proposed framework integrates differential privacy mechanisms, secure aggregation protocols, and a prototype consistency verification module that identifies deviations from expected latent distributions. Beyond technical design, we explore governance implications, deployment challenges in heterogeneous hospital networks, regulatory compliance with HIPAA and GDPR, and sustainability considerations regarding computational and energy costs. System-level robustness is evaluated through cross-domain comparisons with horizontal federated learning and fully centralized approaches, highlighting the nuanced benefits and limitations of vertical split learning in sensitive healthcare environments. We conclude with forward-looking perspectives on adaptive defense strategies, standardization of privacy-preserving benchmarks, and the role of policy in fostering trustworthy AI infrastructure.

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Published

2026-05-05

How to Cite

Dan Xue, & Niklas Barnett. (2026). Privacy-Preserving Vertical Split Learning for Healthcare AI with Prototype-Based Anomaly Detection Against Data Poisoning. Computational Intelligence Systems, 4(1). Retrieved from https://scivexus.org/index.php/CIS/article/view/355