Table 1. Sample collection and in-country laboratory analysis.

	Thailand	Tanzania	Zimbabwe	Soweto South Africa	Vulindlela South Africa	Africa (4 sites)
Eligible participantsa	8,041	9,974	12,666	14,682	12,139	49,461
Participants with blood samplesb	7,619	9,041	11,880	13,929	11,843	46,693
HIV NEG	7,502	8,312	10,313	11,922	8,148	38,695
HIV DISC	39	187	19	22	46	274
HIV POS	78	542	1,548	1,985	3,649	7,724
Initial estimate of HIV prevalencec	1.02%	5.99%	13.0%	14.3%	30.8%	16.5%

^aExcludes participants who were not contacted, declined participation, or did not meet enrollment criteria.

^bSamples were not obtained for 2,744 eligible participants (2,310 no consent, 439 blood draw failure, 19 excluded for other reasons). The HIV status of study participants was initially characterized based on the results of the two HIV rapid tests performed in-country (see Methods): HIV POS: two reactive HIV rapid tests. HIV DISC: one reactive and one non-reactive HIV rapid test. HIV NEG: two non-reactive HIV rapid tests.

^cAn initial estimate of HIV prevalence was based on in-country testing (calculated as # HIV POS samples/total # samples×100).