Effectiveness of a train-the-trainer workshop series on teaching methods among nurse educators: an exemplar from Vietnam - Hoang, Van Lan; Bui, Hien Thi; Le, Thuy Thi; Tran, Duong Thuy; Hoang, Hue Thi; Huynh, Hong Thuy Phuong; Nguyen, Thi Hoa Huyen (Frontiers in Education, 2025)