TABLE 1.

Interassay and intra-assay variability

Type of comparison	No. of input copies	No. of HIV DNA copies/reaction in calculated standard replicate				Mean no. of HIV DNA copies/reaction	CV (%)	Maximum Z score
		1	2	3	4
Intra-assay	5	5	6	5	5	5	6	0.23
	25	10	19	17	18	16	26	1.34
	100	97	122	44	89	88	37	2.07
	1,000	2,579	2,670	1,619	1,475	2,085	30	1.21
	10,000	10,000	7,782	4,943	7,661	7,596	27	1.44
Interassay	5	3	2	7	7	5	53	2.56
	25	61	46	34	41	46	25	1.20
	100	118	71	80	70	85	27	1.07
	1,000	1,344	1,773	2,136	849	1,525	36	1.89
	10,000	7,112	6,878	10,000	7,507	7,874	18	0.77