Table 3.

Diagnostic characteristics of various alanine aminotransferase cut-off levels for detecting lamivudine resistance

ALT (U/L)	Sensitivity (%)	Specificity (%)	Positive predictive value (%)	Negative predictive value (%)	Positive likelihood ratio	Negative likelihood ratio
> 42.5	61	60	60	61	1.53	0.65
> 70	39	81	67	58	2.05	0.75
> 30 (males)	85	28	53	66	1.18	0.56
> 19 (females)	90	7	50	40	0.96	1.40

The alanine aminotransferase (ALT) value of 42.5 U/L was found to be the best curve to fit receiver operating characteristics, while the ALT value of 70 U/L was the upper cutoff limit of the normal range in our laboratory, and ALT 30 U/L and 19 U/L were the cutoff values for males and females, respectively, based on the new Association for Study of Liver Disease guidelines.