Table 1.

Description of the kit used in each site during the study period

CENTERID	Period	Screening Test Kit	Number of Screened Units	% of Screened Units	False Positive	% of False Positive
Hemope (Recife)	1. 01/01/2007 -- 21/07/2007	C: Bioschile	56132	9.2	10	0.02
	2. 22/07/2007 -- 31/12/2008	B: Elisa Cruzi - Biomerieux	145363	23.9	64	0.04
Hemominas (Belo Horizonte)	1. 01/01/2007 -- 11/02/2007	C: Bioschile	9056	1.5	0	0.00
	2. 12/02/2007 -- 26/09/2007	D: Gold Chagas REM	42589	7.0	221	0.52
	3. 27/09/2007 -- 16/01/2008	B: Elisa Cruzi - Biomerieux	20653	3.4	4	0.02
	4. 17/01/2008 -- 31/12/2008	D: Gold Chagas REM	64589	10.6	25	0.04
FPS/HSP (São Paulo)	1. 01/01/2007 -- 22/02/2007	B: Elisa Cruzi - Biomerieux	20352	3.3	7	0.03
	2. 23/02/2007 -- 27/02/2007	A:Chagateck - Biomerieux	1666	0.3	1	0.06
	3. 28/02/2007 -- 31/12/2008	B: Elisa Cruzi - Biomerieux	248190	40.8	157	0.06