Table 4.

Mean CVs for all targets passing presence / absence filter in analysis of U133A and U133B arrays

	Mean CV with signal method (%)	Mean CV with ratio method (%)	Reduction in mean CV with ratio method (%)
U133A, initial scan, 9276 targets
8 samples from young men	26.5	21.2	20
8 samples from old men	26.5	19.2	28
U133A, antibody-enhanced scan, 10665 targets
8 samples from young men	25.8	20.2	22
8 samples from old men	23.5	18.4	22
U133B, initial scan, 5766 targets
8 samples from young men	29.8	23.9	20
8 samples from old men	27.5	22.1	20
U133B, antibody-enhanced scan, 7571 targets
8 samples from young men	28.1	22.2	21
8 samples from old men	26.1	20.4	22