Table 6.

Summary of within-run CV(%) for spiked samples (n = 20), between-run CV(%) for spiked samples (n = 20 over 5 consecutive days), and QCM (n = 17 for urine and n = 22 for serum, over 1 mo).

	Within-run spiked sample	Between-run spiked sample	QCM sample
Serum low	1.4 μg/dL	1.4 μg/dL	K9CON QCM1: 7 μg/dL
CV	7.5%	9.5%	4.1%
Serum high	20 μg/dL	20 μg/dL	K9CON QCM2: 14 μg/dL
CV	4.7%	7.4%	7%
Urine low	1.4 μg/dL	1.4 μg/dL	Liquicheck QCM1: 6.7 μg/dL
CV	6.4%	9.6%	5.4%
Urine high	20 μg/dL	20 μg/dL	Liquicheck QCM2: 23.5 μg/dL
CV	2.5%	4.6%	4.5%

K9CON (Immulite Systems Control; Siemens); Liquicheck (Bio-Rad).