Table 5.

Summary of the posterior probability estimates obtained for the parameters that measure the effect of the cth covariate on the sensitivity and specificity of kth test and on disease prevalence in vth stratum, using model ModII (L = 6, M = 3, V = 2).

Sensitivity (α ck)					Specificity (β ck)
Test	Parameter	Mean	P2.5%	P97.5%	Test	Parameter	Mean	P2.5%	P97.5%
ELISA	α 11	5.91	3.03	8.79	ELISA	α 01	3.47	1.80	5.10
	γ 111	0.50	0.02	0.96		γ 011	−1.92	−2.79	−0.94
	γ 112	0.51	0.03	1.00		γ 012	−2.10	−2.90	−1.14
	γ 113	0.50	−0.01	0.96		γ 013	−2.12	−2.89	−1.11
IIF	α 12	5.79	2.89	8.82	IIF	α 02	6.51	3.01	9.73
	γ 121	0.51	0.04	0.99		γ 021	−2.08	−2.89	−1.02
	γ 122	0.49	0.00	0.98		γ 022	−2.12	−2.89	−1.16
	γ 123	0.50	0.02	1.00		γ 023	−2.12	−2.89	−1.10
IHA	α 13	5.77	2.76	8.65	IHA	α 03	6.56	2.88	10.01
	γ 131	0.51	0.03	0.99		γ 031	−2.10	−2.86	−1.05
	γ 132	0.49	0.01	0.97		γ 032	−2.11	−2.91	−1.11
	γ 133	0.51	0.04	0.98		γ 033	−2.12	−2.85	−1.15
HEMO	α 14	−0.50	−0.78	−0.22	HEMO	α 04	100	100	100
	γ 141	0.38	−0.06	0.84		γ 041	0	0	0
	γ 142	0.45	0.02	0.89		γ 042	0	0	0
	γ 143	0.31	−0.12	0.74		γ 043	0	0	0
c-ELISA	α 15	5.76	2.87	8.75	c-ELISA	α 05	2.00	1.01	2.97
	γ 151	0.51	0.02	1.00		γ 051	−1.91	−2.77	−0.94
	γ 152	0.49	0.04	0.97		γ 052	−2.11	−2.90	−1.07
	γ 153	0.49	0.00	0.98		γ 053	−2.08	−2.85	−1.11
rec-ELISA	α 16	5.72	2.82	8.70	rec-ELISA	α 06	6.50	3.16	10.03
	γ 161	0.21	−0.18	0.74		γ 061	−2.08	−2.87	−1.05
	γ 162	0.54	0.07	1.00		γ 062	−2.09	−2.90	−1.03
	γ 163	0.46	−0.05	0.97		γ 063	−2.11	−2.88	−1.09
Prevalence (γ cv)
Stratum	Parameter	Mean	P2.5%	P97.5%	Stratum	Parameter	Mean	P2.5%	P97.5%
I	α 1	0.50	0.21	0.81	II	α 2	−2.01	−2.92	−1.03
	γ 11	0.51	0.11	0.91		γ 21	0.41	−0.04	0.84
	γ 12	0.43	0.00	0.85		γ 22	0.49	0.03	0.94
	γ 13	0.69	0.28	1.12		γ 23	0.43	−0.02	0.89

P2.5%: 2.5th percentile; P97.5%: 97.5th percentile; ELISA: enzyme-linked immunosorbent assay; IIF: indirect immunofluorescence; IHA: indirect hemagglutination; HEMO: blood culture; c-ELISA: conventional ELISA using the Biomanguinhos kit; rec-ELISA (recombinant ELISA using the Biomanguinhos kit and CRA and FRA antigens); c = 1: AGE-age (≤30, >30 years); c = 2: GEN-gender (male, female); c = 3: RFE-presence of at least two of three risk factors epidemiological (origin from an endemic region, contact with the vector transmitting the disease, and family history of Chagas' disease); Stratum I (v = 1) donors with negative or positive serology and Stratum II (v = 2) with inconclusive serology in the screening test; γ _1kc: effect of the cth covariate on the sensitivity of kth test; γ _0kc: effect of the cth covariate on the specificity of kth test; γ _vc: effect of the cth covariate on disease prevalence in vth stratum.