Evaluation of awake prone positioning effectiveness in moderate to severe COVID-19 by Truong, NT, Phong, NT, Nguyen, NT, Khanh, LTT, Tran, LHB, Linh, NTM, Thao, DP, Trinh, NTD, Kieu, PT, Thao, NTP, Hoang, VT, Ngoc, NT, Oanh, PKN, Vien, TTD, Tung, NLN, Ly, VT, Khoa, TD, Phu, NH, Van, CTC, Duc, TM, Beane, A, Khoa, LDV, Clifton, D, Kestelyn, E, Hai, HB, Yen, LM, Tan, LV, Glover, G, Thwaites, G, Geskus, R, Duc, DH, Dung, NT, Thwaites, L