“…Federated learning models, such as decentralized independent component analysis ( Baker et al, 2015 ), sparse regression ( Plis et al, 2016 ), and distributed deep learning ( Kaissis et al, 2021 ; Stripelis et al, 2021 ; Warnat-Herresthal et al, 2021 ), have made solid progress with leveraging multivariate image features for statistical inferences, allowing iterative computation on remote datasets. Some other recent studies focus on multivariate linear modeling ( Silva et al, 2020 ), federated gradient averaging ( Remedios et al, 2020 ), and unbalanced data for multi-site ( Yeganeh et al, 2020 ). To our knowledge, these methods have not yet been applied to detect multimodal associations in AD research, such as finding anatomically abnormal regions on MRI that are associated with Aβ/tau pathology defined using PET.…”