Fig. 2.

Receiver operator characteristic curve (ROC) to assess the ability of the Diaphragm Thickening Fraction (DTF) to predict noninvasive ventilation (NIV) outcome for operator 1 (A) and 2 (B), respectively. Area under the ROC curve (AUC) 0.84 (95% CI 0.74 to 0.91) for operator 1 and 0.76 (95% CI 0.65 to 0.85) for operator 2