Federated Tensor Factorization for Computational Phenotyping
This addresses the challenge of population bias in computational phenotyping for healthcare data analysis, enabling collaborative research across institutions with strict privacy policies, though it is incremental as it adapts existing methods to a federated setting.
The paper tackled the problem of deriving clinical phenotypes from electronic health records across multiple hospitals without sharing patient-level data, by developing a federated tensor factorization method that achieves accuracy and phenotype discovery comparable to centralized training while preserving privacy.
Tensor factorization models offer an effective approach to convert massive electronic health records into meaningful clinical concepts (phenotypes) for data analysis. These models need a large amount of diverse samples to avoid population bias. An open challenge is how to derive phenotypes jointly across multiple hospitals, in which direct patient-level data sharing is not possible (e.g., due to institutional policies). In this paper, we developed a novel solution to enable federated tensor factorization for computational phenotyping without sharing patient-level data. We developed secure data harmonization and federated computation procedures based on alternating direction method of multipliers (ADMM). Using this method, the multiple hospitals iteratively update tensors and transfer secure summarized information to a central server, and the server aggregates the information to generate phenotypes. We demonstrated with real medical datasets that our method resembles the centralized training model (based on combined datasets) in terms of accuracy and phenotypes discovery while respecting privacy.