“…All, except four (20.0%), of these publications were from China [ 35 , 42 , 49 , 58 ]. Severe COVID-19 was defined based on World Health Organization guidance in three (15.0%) studies [ 35 , 49 , 58 ], recommendations from international professional bodies in two (10.0%) studies [ 44 , 70 ], national guidelines in 11 (55.0%) studies [ 38 , 42 , 46 , 47 , 51 , 53 , 56 , 57 , 73 , 74 , 76 ], and institutional policy in four (20.0%) studies [ 54 , 55 , 75 , 77 ]. Only three (15.0%) studies were considered high quality [ 42 , 54 , 58 ].…”