TABLE 1.

Experiment A: variability of sensitivity depending on different pretreatments and blood components

Pretreatment	Blood component	No. of PCR replicates/ expta	Result for a mycobacterial concentrationb (CFU/ml) of:
			300			30			3			1
			No. of pos replicates/ expt	Proportion of pos replicates/ expt	Sensitivity/ replicate (%)	No. of pos, replicates/ expt	Proportion of pos replicates expt	Sensitivity/ replicate (%)	No. of pos replicates/ expt	Proportion of pos replicates/ expt	Sensitivity/ replicate (%)	No. of pos replicates/ expt	Proportion of pos replicates/ expt	Sensitivity/ replicate (%)
SDS 1%	Lysate pellet	8	8	1.00	87	4	0.50	50	5	0.62	50	2	0.25	20
		8	6	0.75		4	0.50		4	0.50		2	0.25
		8	7	0.87		4	0.50		3	0.37		1	0.12
M-PRM	PMNC	8	6	0.75	62	4	0.50	45	1	0.12	8	0	0.00	0
		8	4	0.50		4	0.50		1	0.12		0	0.00
		8	5	0.62		3	0.37		0	0.00		0	0.00
M-PRM	PBMC	8	4	0.50	41	2	0.25	20	1	0.12	8	0	0.00	0
		8	3	0.37		2	0.25		1	0.12		0	0.00
		8	3	0.37		1	0.12		0	0.00		0	0.00

^aTotal of three experiments. 

^bPos, positive.