Pooling cohorts for deep learning analysis: a potential source of bias for electrocardiogram analysis. - Marie Mørch-Pedersen; Malene Nørregaard; Claus Graff; Oliver B. Vad; Pia R. Lundegaard; Jesper Hastrup Svendsen; Torben Hansen; Allan Linneberg; Peter G. Jørgensen; Magnus T. Jensen; Peter Rossing; Christina Ellervik; et al. (Biomed. Signal Process. Control., 2026)