Risk factors and mortality rate in Covid-19 critically ill patients in Mexico. (December 2021) - Bejarano, M.; Ramos, C.O.; Rosas, E.A.; Madera, C.E.; Rascón, R.; Balderas, C.; Cabrera, Á.; Rocha, U.; Fuchs, V.; Sánchez, A.; Bermeo, E.; Guzmán, R.; et al.