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arXiv · 2509.20867

Federated Markov Imputation: Privacy-Preserving Temporal Imputation in Multi-Centric ICU Environments

Christoph Düsing·Philipp Cimiano
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Abstract

Missing data is a persistent challenge in federated learning on electronic health records, particularly when institutions collect time-series data at varying temporal granularities. To address this, we propose Federated Markov Imputation (FMI), a privacy-preserving method that enables Intensive Care Units (ICUs) to collaboratively build global transition models for temporal imputation. We evaluate FMI on a real-world sepsis onset prediction task using the MIMIC-IV dataset and show that it outperforms local imputation baselines, especially in scenarios with irregular sampling intervals across ICUs.

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Christoph Düsing, Philipp Cimiano. 2025-09-25. Federated Markov Imputation: Privacy-Preserving Temporal Imputation in Multi-Centric ICU Environments. https://arxiv.org/abs/2509.20867

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