Fig. 3From: Use of high-flow nasal cannula oxygen and risk factors for high-flow nasal cannula oxygen failure in critically-ill patients with COVID-19Receiver operating characteristics curve for the ability of the ROX index calculated six hours after high-flow nasal cannula oxygen therapy (HFNC) initiation (6-h ROX index) to predict HFNC failure (n = 114). AUC area under the curve, expressed as mean [95% confidence interval]Back to article page