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Table 3 Associations between Tuberculosis Contact Score, the Infectivity Score and other risk factors for tuberculosis (TB) and the dependant variables TST1 and QFT1 in 525 household contacts of 161 adults with pulmonary TB

From: Identification of subclinical tuberculosis in household contacts using exposure scores and contact investigations

 TST- vs TST + 1QFT- vs QFT + 1
univariatemultivariate2multivariate3univariatemultivariate2multivariate3
OR (95%CI)OR (95%CI)OR (95%CI)OR (95%CI)OR (95%CI)OR (95%CI)
Tuberculosis Contact Score1.15 (1.05, 1.26)1.16 (1.01, 1.33) 1.22 (1.12, 1.32)1.33 (1.16, 1.51) 
InfectivityScore1.28 (1.11, 1.48) 1.39 (1.10, 1.76)1.25 (1.11, 1.42) 1.41 (1.16, 1.71)
Gender1.44 (0.97, 2.13)1.35 (0.85, 2.15)1.37 (0.87, 2.18)1.38 (0.95, 1.99)1.38 (0.88, 2.16)1.47 (0.94, 2.28)
Age (years)4
  < 50.44 (0.19, 1.02)0.71 (0.27, 1.87)0.72 (0.28, 1.88)0.46 (0.23, 0.91)0.87 (0.36, 2.11)0.81 (0.34, 1.92)
 5–141.07 (0.70, 1.62)1.05 (0.61, 1.82)1.05 (0.61, 1.82)1.20 (0.79, 1.81)1.27 (0.74, 2.17)1.32 (0.77, 2.24)
  > 14refrefrefrefrefref
 BCG scar present0.93 (0.62, 1.38)1.04 (0.65, 1.65)1.02 (0.64, 1.63)0.66 (0.45, 0.97)0.64 (0.40, 1.01)0.63 (0.40, 1,00)
Individual risk factors
 Diabetes mellitus0.26 (0.03, 2.09)0.22 (0.03, 1.83)0.22 (0.03, 1.84)2.80 (0.58, 13.61)3.41 (0.62, 18.69)3.26 (0.60, 17.79)
 Smoking1.21 (0.78, 1.86)1.64 (0.93, 2.89)1.67 (0.94, 2.96)1.18 (0.77, 1,79)1.15 (0.65, 2.04)1.15 (0.65, 2.03)
  ≥ 1 individual risk factors1.19 (0.77, 1.82)  1.21 (0.80, 1.84)  
 BMI5a0.98 (0.90, 1.05)0.96 (0.86, 1.06)0.96 (0.88, 1.06)1.03 (0.96, 1.11)0.97 (0.88, 1.06)0.99 (0.90, 1.08)
 BMIZ5b1.03 (0.86, 1.24)nana1.16 (0.97, 1.38)nana
Environmental risk factors
 Crowding61.01 (0.91, 1.11)1.09 (0.97, 1.22)1.09 (0.97, 1.22)0.92 (0.84, 1.01)0.99 (0.88, 1.11)0.97 (0.87, 1.08)
In-door pollution7
 LPG1.78 (1.01, 3.15)2.05 (1.07, 3.93)1.96 (1.02, 3.76)1.48 (0.81, 2.68)1.28 (0.65, 2.54)1.25 (0.63, 2.47)
 Kerosene1.89 (0.62, 5.76)2.17 (0.67, 7.08)2.34 (0.72, 7.59)1.80 (0.55, 5.96)1.15 (0.33, 4.09)1.37 (0.39, 4.83)
 Wood + agri residuerefrefrefrefrefref
  1. 1Tuberculin Skin Test (TST) was dichotomized around the cutoff 10 mm; ≥10 mm corresponding to TST+ and < 10 mm corresponding to TST-. Quantiferon (QFT) was dichotomized around the cutoff 0.35 IU/mL; ≥0.35 IU/mL corresponding to QFT+ and < 0.35 IU/mL corresponding to QFT- (Subjects with indeterminate QFT is excluded from analysis). 2Analysis including the TCS; 3Analysis including the Infectivity Score. 4WHO based age categories. 5Since assessments of body weight is different in 5asubjects aged ≥15 years (Body Mass Index, BMI) and 5b < 15 years (Body Mass Index Z-score, BMIZ), BMI and BMIZ were only entered in the models evaluating this variable, which were then done stratified for age. 6Number of household members divided on rooms in the house. 7Grading based on type of fuel, (Wood + agricultural residue) = 3, Kerosene = 2, LPG = 1
  2. ORs in bold are significantly different from 1 (p<0.05)