Table 2. Adjusted odds ratios (95% CI) measuring the associations between Western blot reactivity and ELISA values (25–75 percentile increase) among 189 study participants^a,b.

ELISA	Blood donor, n = 95 (95% CI)	PCP+, n = 33 (95% CI)	PCP–, n = 61 (95% CI)	HIV, n = 94 (95% CI)
1	1.1 (0.9 to 1.4)	5.1 (2.2 to 11.8)	1.4 (0.8 to 2.6)	2.7 (1.2 to 5.8)
2	1.1 (0.9 to 1.4)	20.4 (6.4 to 65.1)	3.6 (2.0 to 6.6)	8.6 (4.4 to 16.9)
3	1.0 (0.9 to 1.1)	11.6 (3.6 to 37.9)	7.4 (3.6 to 15.1)	9.3 (4.7 to 18.5)

^aCI, confidence interval; ELISA, enzyme-linked immunosorbent assay; PCP, Pneumocystis pneumonia.
^bOdds ratios were obtained by using logistic regression. Positive associations were found between Western blot reactivity and increasing ELISA. Based on 95% confidence intervals, the odds of Western blot reactivity were significantly related (p < 0.05) to increasing ELISA 1, 2, and 3 among PCP+ patients and HIV patients across all antigens. For PCP– patients this result was true for ELISA 2 and 3 only. No significant results were found for the blood donor group.