Table 3.

Different cut-off values selected by the highest Youden index. The sensitivity (%), specificity (%), positive likelihood ratio (LR+), negative likelihood ratio (LR−), and calculated Youden index for specific cut-off values are shown. Values were selected by the highest Youden index (9, 10, 11, 12, and 13) and compared with a value (5) recommended in the original work by Buysse et al. [11]. The total area under curve (AUC) was 0.80.

Cut-off point	Sensitivity (%)	Specificity (%)	LR+	LR−	Youden index
5	97.24%	30.81%	1.41	0.09	0.28
9	68.71%	69.19%	2.23	0.45	0.38
10	63.5%	79.29%	3.07	0.46	0.43
11	56.75%	87.37%	4.49	0.50	0.44
12	50.31%	94.95%	9.96	0.52	0.45
13	45.71%	95.96%	11.31	0.57	0.42