Machine-Learning Approaches for Predicting the Need of Oxygen Therapy in Early-Stage COVID-19 in Japan: Multicenter Retrospective Observational Study oleh Syunsuke Yamanaka, Koji Morikawa, Hiroyuki Azuma, Maki Yamanaka, Yoshimitsu Shimada, Toru Wada, Hideyuki Matano, Naoki Yamada, Osamu Yamamura, Hiroyuki Hayashi