TABLE 1.

LODs (95% CI) using PROBIT analysis

Virus	Titera	Positivity rate (no. positive/total)		% Positive	LOD (95% CI)	Avg recovery rate (%)b
		Run no. 1	Run no. 2
HBV type A adw	0	0/24	0/24	0	30 copies/ml (22–60)	54
	12	19/24	19/24	79.1
	25	22/24	21/23	89.6
	50c	24/24	24/24	100.0
	100	24/24	24/24	100.0
	200	24/24	24/24	100.0
HCV type 1b	0	0/24	0/23	0.0	77 IU/ml (61–112)	21
	20	13/24	12/18	59.5
	30	11/24	23/23	72.3
	50	20/24	21/22	89.1
	70	22/24	22/23	93.6
	100	23/24	24/24	97.9
	140	23/24	24/24	97.9
	200	24/24	24/24	100.0
HIV-1 type B	0	0/24	0/24	0	42 copies/ml (33–66)	33
	16	16/23	15/24	66.0
	32	21/24	22/24	89.6
	64	24/24	23/24	97.9
	80	24/24	23/23	100.0
	190	24/24	24/24	100.0
	260	24/24	24/24	100.0

^aUnits: HBV and HIV-1, copies/milliliter; HCV, international units/milliliter. 

^bAverage recovery rate was calculated as follows: calculated copy number/input copy number × 100%, where input copy number was adjusted (titer × 0.2 ml) since the equivalent of 0.2 ml of sample was added to each reaction mixture. 

^cBold numbers indicate the lowest titers that yielded 100% positivity.