Private and interpretable clinical prediction with quantum-inspired tensor train models

TL;DR

This paper introduces a quantum-inspired tensor train approach to enhance privacy and interpretability in clinical prediction models, effectively reducing information leakage and maintaining accuracy.

Contribution

It proposes a novel tensorization method that obfuscates model parameters, improving privacy while preserving interpretability and predictive performance in clinical models.

Findings

Both logistic regression and neural networks leak training data information.

Tensor train models significantly reduce privacy vulnerabilities.

Tensorization maintains model accuracy and interpretability.

Abstract

Machine learning in clinical settings must balance predictive accuracy, interpretability, and privacy. Models such as logistic regression (LR) offer transparency, while neural networks (NNs) provide greater predictive power; yet both remain vulnerable to privacy attacks. We empirically assess these risks by designing attacks that identify which public datasets were used to train a model under varying levels of adversarial access, applying them to LORIS, a publicly available LR model for immunotherapy response prediction, as well as to additional shallow NN models trained for the same task. Our results show that both models leak significant training-set information, with LRs proving particularly vulnerable in white-box scenarios. Moreover, we observe that common practices such as cross-validation in LRs exacerbate these risks. To mitigate these vulnerabilities, we propose a quantum-inspired defense based on tensorizing discretized models into tensor trains (TTs), which fully obfuscates parameters while preserving accuracy, reducing white-box attacks to random guessing and degrading black-box attacks comparably to Differential Privacy. TT models retain LR interpretability and extend it through efficient computation of marginal and conditional distributions, while also enabling this higher level of interpretability for NNs. Our results demonstrate that tensorization is widely applicable and establishes a practical foundation for private, interpretable, and effective clinical prediction.