Development and effectiveness evaluation of an interactive e-learning environment to enhance digital health literacy in cancer patients: study protocol for a randomized controlled trial - Lange-Drenth, Lukas; Willemer, Hellena; Banse, Mirjam; Ernst, Anke; Daubmann, Anne; Holz, Anja; Bleich, Christiane; Weg-Remers, Susanne; Schulz, Holger (Frontiers in Digital Health, 2025)