Table 3.

ROC curves of hepatitis B surface antigen levels and hepatitis B surface antigen changes on the prediction of hepatitis B surface antigen clearance

Factors	Area	SD	95%CI	Cut-off point	Sensitivity and specificity	HBsAg clearance rate
Age in yr	0.699	0.056	(0.589-0.809)	33	55.9%, 77.2%	58.1% (18/31)
Baseline HBsAg as log10 IU/mL	0.689	0.059	(0.573-0.806)	2.25	52.9%, 80.7%	62.1% (18/29)
Week 12 HBsAg as log10 IU/mL	0.877	0.04	(0.803-0.951)	1.89	85.3%, 82.5%	73.7% (28/38)
Week 24 HBsAg as log10 IU/mL	0.921	0.03	(0.861-0.980)	1.46	94.1%, 78.9%	72.7% (32/44)
HBsAg decline as log10 IU/mL
From baseline to week 12	0.901	0.032	(0.839-0.963)	0.5	85.3%, 88.7%	80.0% (28/35)
From baseline to week 24	0.924	0.031	(0.864-0.985)	1.0	91.2%, 86.0%	77.5% (31/40)

ROC: Receiver operator characteristic; SD: Standard deviation; CI: Confidence interval; HBsAg: Hepatitis B surface antigen; UI: International unit.