Prediction of noninvasive ventilation failure using the ROX index in patients with de novo acute respiratory failure

Annals of Intensive Care

Table 2 Predictive power of NIV failure tested by different ROX index

Cutoff value	Probability of NIV failure (%)	Sensitivity (%)	Specificity (%)
After 1–2 h NIV, N = 1286
2	75	100	2.1
4	65	95.0	24.3
6	50	75.9	56.7
8	37	45.7	79.6
10	25	22.8	91.4
After 12 h NIV, N = 1068
2	79	100	1.4
4	67	97.9	19.5
6	53	85.7	48.6
8	37	61.5	71.6
10	24	33.7	88.5
After 24 h NIV, N = 911
2	82	99.8	1.2
4	69	98.1	24.9
6	52	87.4	50.2
8	35	64.5	76.9
10	21	38.6	88.6