Table 4.

Predictive values of the ROX, mROX, ROX-HR, and mROX-HR indices for HFNC success 

Indices	AUROC	95% CI	Cutoff	Sensitivity	Specificity	p value
Baseline mROX	0.661	0.540–0.782	7.1	0.431	1.00
Baseline ROX-HR	0.676	0.557–0.796	7.9	0.471	0.917
Baseline mROX-HR	0.722	0.610–0.835	6.7	0.510	0.958
2 h ROX	0.829	0.721–0.937	6.2	0.824	0.750	0.1997
2 h mROX	0.878	0.795–0.961	4.3	0.961	0.708
2 h ROX-HR	0.855	0.757–0.954	5.8	0.784	0.833	0.2141
2 h mROX-HR	0.891	0.812–0.969	4.1	0.902	0.792

Annotation: AUROC, area under the receiver operating characteristic curve; CI: confidence interval; ROX, SpO₂ /FiO₂ (%) to RR (breaths/min);mROX, PaO_2/FiO₂(%) to RR(breaths/min);ROX-HR,ROX /HR*100 ;mROX-HR,mROX /HR*100