Table 3. Logistic regression modeling for confirmed or probable TB disease in household contacts ≥15 years of age^*.

		n/N (%) 38/704 (5%)	Univariable		Multivariable
			Odds Ratio [95% CI]	P value	Odds Ratio [95% CI]	P value
HHC’s Age	15–24 years	7/189 (4%)	0.3 [0.1, 0.8]	0.020	0.5 [0.2, 1.1]	0.011
	25–49 years	14/341 (4%)	0.4 [0.2, 0.7]		0.3 [0.1, 0.6]
	≥50 years	17/174 (10%)	1.0 (ref)		1.0 (ref)
HHC’s Sex	Male	15/259 (6%)	1.1 [0.6, 2.2]	0.72
	Female	23/445 (5%)	1.0 (ref)
HHC’s HIV Status	HIV-positive	3/59 (5%)	0.9 [0.3, 2.7]	0.09	0.5 [0.1, 2.7]	0.07
	Unknown	3/130 (2%)	0.4 [0.1, 1.1]		0.3 [0.1, 1.0]
	HIV-negative	32/515 (6%)	1.0 (ref)		1.0 (ref)
HHC’s History of COPD/Asthma	Yes	3/29 (10%)	1.9 [0.6, 6.1]	0.41
	No	34/661 (5%)	1.0 (ref)
HHC’s History of Previous TB Treatment	Yes	21/77 (27%)	12.3 [6.3, 24.2]	<0.001	9.7 [4.5, 21.1]	<0.001
	No/Unknown	17/627 (3%)	1.0 (ref)		1.0 (ref)
HHC Incarcerated Past 12 Mos.	Yes	1/20 (5%)	0.7 (0.1, 8.4)	0.76
	No	37/683 (6%)	1.0 (ref)
HHC Used Alcohol Almost Every Day Sometime in Past 12 Mos.	Yes	11/56 (20%)	5.5 [2.6, 11.7]	0.008	3.1 [1.3, 7.5]	0.033
	No	27/640 (4%)	1.0 (ref)		1.0 (ref)
HHC Incarceration, Substance and/or Alcohol Use Composite in Past 12 Mos.a	Incarcerated	1/20 (5%)	1.2 [0.1, 10.0]	0.023
	Never Incarcerated, Used Substances and/or Alcohol	14/82 (17%)	4.8 [2.3, 9.9]
	Never Incarcerated, Did Not Use Substances or Alcohol	23/593 (4%)	1.0 (ref)
HHC’s Smoking History	Current	20/151 (13%)	6.2 [3.1, 12.4]	<0.001	2.9 [1.3, 6.4]	0.031
	Previous	7/54 (13%)	6.3 [2.5, 16.0]		4.2 [1.5, 11.7]
	Never	11/499 (2%)	1.0 (ref)		1.0 (ref)
Index Participant’s Sputum Smear	AFB-positive	24/325 (7%)	2.1 [1.0, 4.4]	0.06
	AFB-negative/Unknown	14/379 (4%)	1.0 (ref)
Relationship of IP to HHC	Spouse	2/60 (3%)	0.6 [0.2, 2.1]	0.47
	Mother	2/55 (4%)	0.5 [0.1, 2.6]
	Father	1/37 (3%)	0.5 [0.1, 2.4]
	Other	33/552 (6%)	1.0 (ref)
Sleeping Proximity of IP to HHC	Same Room	15/240 (6%)	1.2 [0.6, 2.3]	0.69
	Different Room	23/464 (5%)	1.0 (ref)
Evenings/Week with IP, Past 6 Months	6–7	28/533 (5%)	1.1 [0.3, 3.4]	0.85
	3–5	5/72 (7%)	1.5 [0.4, 6.4]
	≤2	5/98 (5%)	1.0 (ref)
Smokers in Householdb	Any	24/273 (9%)	2.7 [1.3, 5.6]	0.021
	None	14/422 (3%)	1.0 (ref)
Primary Exterior Wall Material	Brick, Cinderblock, Stone with Mortar	25/544 (5%)	1.0 (ref)	0.22
	Adobe, Rammed Earth, Sticks/Stones & Mud, Wood, Straw, Tin, Other	13/156 (8%)	1.8 [0.8, 4.2]

IP, index participant; HHC, household contact; n, number of HHCs with positive IGRA result; N, number of HHCs with determinate IGRA result (positive or negative); %, simple percentage calculated as n/N; CI, confidence interval; ref, reference; mos., months.

* Models use data on HHC ≥15 years of age diagnosed with TB based on study evaluations; eight HHCs with active TB documented before study entry did not have data collection on incarceration, TB symptoms, or HIV status; they also did not have chest x-ray, specimen collection for IGRA, TB diagnostics, or HIV testing. Models were fit using an exchangeable working correlation, unless working correlation was negative (which occurred when data were sparse) in which case an independent working correlation was used. Univariable models include the one characteristic only. Each multivariable model includes characteristics with odds ratios shown. The p values are from score tests.

^a All self-reported. Incarceration is defined as having spent a night in jail, prison, youth detention center, alcohol use as having a period of drinking alcoholic beverages almost every day, and substance use as any use of substances (marijuana, cocaine, etc.) all in the past 12 months.

^b Smoking was defined as smoking tobacco products, ongoing or having quit within the past 6 months.