. 2013 Dec 2;8(12):e82005. doi: 10.1371/journal.pone.0082005

Table 4. Predictors of QFT and T-SPOT positivity (n = 115)^a.

Variables		Unadjusted OR (95% CI)	P value	Adjusted OR (95% CI)	P value
Positive QFT result
Age ≥80 years^b
	No	1	-	1	-
	Yes	4.0 (1.52–10.48)	0.005	5.8 (2.04–16.26)	<0.001
Reason for expert opinion
	COPD	1	-	1	-
	Silicosis	2.1 (0.97–4.50)	0.059	1.8 (0.75–4.28)	0.19
Foreign country of birth^b
	No	1	-	1	-
	Yes	4.3 (1.32–14.24)	0.016	6.8 (1.91–24.0)	0.003
Current smoking
	No	1	-	1	-
	Yes	3.5 (1.04–11.74)	0.043	3.5 (0.92–13.60)	0.066
Radiological evidence of prior healed TB^b
	No	1	-	1	-
	Yes	4.4 (1.59–12.07)	0.004	5.0 (1.69–14.98)	0.004
Positive T-SPOT result
Age ≥80 years^b
	No	1	-	1	-
	Yes	6.4 (1.83–23.40)	0.004	8.1 (2.22–29.21)	0.001
Reason for expert opinion
	COPD	1	-	1
	Silicosis	1.85 (0.83–4.11)	0.13	1.5 (0.63–3.55)	0.36
Foreign country of birth^b
	No	1	-	1	-
	Yes	3.4 (0.91–12.44)	0.070	4.8 (1.26–18.07)	0.022
Current smoking
	No	1	-	1
	Yes	2.8 (0.74–10.47)	0.13	2.6 (0.65–10.65)	0.18
Radiological evidence of prior healed TB
	No	1	-	1	-
	Yes	2.9 (0.98–8.30)	0.055	3.0 (0.96–9.15)	0.059

^aThree subjects with indeterminate test results were excluded from logistic regression analysis.

^bVariable included in final logistic regression model building.

Table 4. Predictors of QFT and T-SPOT positivity (n = 115)a.