Table 3.

ROC analysis of the online social networking addiction scale using the high-risk class derived from latent profile model as gold standard

Cut-off point	True positive	False negative	True negative	False positive	Sensitivity (%)	Specificity (%)	PPV (%)	NPV (%)	Accuracy (%)	Youden index
19	653	0	3,125	1,173	100.0	72.7	35.8	100.0	76.3	72.7
20	653	0	3,449	849	100.0	80.2	43.5	100.0	82.9	80.2
21	652	1	3,714	584	99.8	86.4	52.8	100.0	88.2	86.3
22	649	4	3,937	361	99.4	91.6	64.3	99.9	92.6	91.0
23	635	18	4,092	206	97.2	95.2	75.5	99.6	95.5	92.5
24	590	63	4,193	105	90.4	97.6	84.9	98.5	96.6	87.9
25	409	244	4,248	50	62.6	98.8	89.1	94.6	94.1	61.5
26	331	322	4,283	15	50.7	99.7	95.7	93.0	93.2	50.3
27	257	396	4,296	2	39.4	100.0	99.2	91.6	92.0	39.3
28	196	457	4,297	1	30.0	100.0	99.5	90.4	90.7	30.0

PPV: Positive predictive value; NPV: Negative predictive value.