Table 1. Factors associated with positive TST and /or QFT-GIT assays.
| Variables | TST | QFT-GIT | ||||
|---|---|---|---|---|---|---|
| Neg. (n = 391) |
Pos. (n = 478) |
Sig. | Neg. (n = 401) |
Pos. (n = 468) |
Sig. | |
| Age (years) | ||||||
| <6 years | 38 (61.3%) | 24 (38.7%) | <0.001 | 44 (71.0%) | 18 (29.0%) | <0.001 |
| 6–15 years | 94 (57.3%) | 70 (42.7%) | 99 (60.4%) | 65 (39.6%) | ||
| 15–45 | 216 (41.9%) | 299 (58.1%) | 216 (41.9%) | 299 (58.1%) | ||
| >45 | 43 (33.6%) | 85 (66.4%) | 42 (32.8%) | 86 (67.2%) | ||
| Gender | ||||||
| Male | 217 (45.2%) | 263 (54.8%) | >0.950 | 226 (47.1%) | 254 (52.9%) | 0.539 |
| Female | 174 (44.7%) | 215 (55.3%) | 175 (45.0%) | 214 (55.0%) | ||
| Employed (Housewife, Retired & Student included in No) | ||||||
| Yes | 207 (41.0%) | 298 (59.0%) | 0.006 | 207 (41.0%) | 298 (59.0%) | <0.001 |
| No | 184 (50.5%) | 180 (49.5%) | 194 (53.3%) | 170 (46.7%) | ||
| Body Mass Index (kg/m2) | ||||||
| <18.5 | 161 (53.1%) | 142 (46.9%) | 0.001 | 167 (55.1%) | 136 (44.9%) | <0.001 |
| 18.5–24.9 | 136 (41.5%) | 192 (58.5%) | 142 (43.3%) | 186 (56.7%) | ||
| >24.9 | 82 (38%) | 134 (62%) | 83 (38.4%) | 133 (61.6%) | ||
| BCG Scar | ||||||
| Present | 235 (48.7%) | 248 (51.3%) | 0.016 | 223 (46.2%) | 260 (53.8%) | >0.950 |
| Absent | 156 (40.4%) | 230 (59.6%) | 178 (46.1%) | 208 (53.9%) | ||
| Smoker | ||||||
| Current | 22 (45.8%) | 26 (54.2%) | <0.001 | 20 (41.7%) | 28 (58.3%) | <0.001 |
| Anytime | 5 (26.3%) | 14 (73.7%) | 3 (15.8%) | 16 (84.2%) | ||
| Non-smokers | 239 (40.5%) | 351 (59.5%) | 244 (41.4%) | 346 (58.6%) | ||
| NA | 125 (59.0%) | 87 (41.0%) | 134 (63.2%) | 78 (36.8%) | ||
| Alcohol Intake | ||||||
| Yes | 46 (42.2%) | 63 (57.8%) | <0.001 | 40 (36.7%) | 69 (63.3%) | <0.001 |
| No | 220 (40.1%) | 328 (59.9%) | 227 (41.4%) | 321 (58.6%) | ||
| NA | 125 (59.0%) | 87 (41.0%) | 134 (63.2%) | 78 (36.8%) | ||
| Diabetes (HbA1cEntry > 6.5 or Known DM or Glucose > = 200) | ||||||
| Yes | 22 (37.9%) | 36 (62.1%) | <0.001 | 25 (43.1%) | 33 (56.9%) | <0.001 |
| No | 244 (40.7%) | 355 (59.3%) | 242 (40.4%) | 357 (59.6%) | ||
| NA | 125 (59.0%) | 87 (41.0%) | 134 (63.2%) | 78 (36.8%) | ||
| HIV | ||||||
| Positive | 7 (43.8%) | 9 (56.3%) | >0.950 | 5 (31.3%) | 11 (68.8%) | 0.313 |
| Negative | 384 (45.0%) | 469 (55.0%) | 396 (46.4%) | 457 (53.6%) | ||
| TST Type | ||||||
| Span | 376 (50.5%) | 369 (49.5%) | <0.001 | 349 (46.8%) | 396 (53.2%) | NA |
| SSI | 15 (12.1%) | 109 (87.9%) | 52 (41.9%) | 72 (58.1%) | ||
| TB Contact (Outside Household) | ||||||
| Yes | 28 (38.4%) | 45 (61.6%) | 0.269 | 30 (41.1%) | 43 (58.9%) | 0.392 |
| No | 363 (45.6%) | 433 (54.4%) | 371 (46.6%) | 425 (53.4%) | ||
| Average Time Spent with Index per Day | ||||||
| <1 hr | 11 (45.8%) | 13 (54.2%) | 0.667 | 14 (58.3%) | 10 (41.7%) | 0.100 |
| 1 to 6 hrs | 43 (48.3%) | 46 (51.7%) | 37 (41.6%) | 52 (58.4%) | ||
| >6 to < 12 hrs | 148 (42.3%) | 202 (57.7%) | 171 (48.9%) | 179 (51.1%) | ||
| >12 but < 18 hrs | 129 (48.5%) | 137 (51.5%) | 107 (40.2%) | 159 (59.8%) | ||
| ≥18 hrs | 59 (42.8%) | 79 (57.2%) | 71 (51.4%) | 67 (48.6%) | ||
| Don't Know | 1 (50.0%) | 1 (50.0%) | 1 (50.0%) | 1 (50.0%) | ||
| Sleeping with Index (After Diagnosis) | ||||||
| Same room, same bed | 106 (42.2%) | 145 (57.8%) | 0.618 | 100 (39.8%) | 151 (60.2%) | 0.028 |
| Same room, diff. bed | 163 (44.9%) | 200 (55.1%) | 169 (46.6%) | 194 (53.4%) | ||
| Same house | 117 (48.1%) | 126 (51.9%) | 128 (52.7%) | 115 (47.3%) | ||
| Others | 5 (41.7%) | 7 (58.3%) | 4 (33.3%) | 8 (66.7%) | ||
| Sharing Meals | ||||||
| None | 14 (41.2%) | 20 (58.8%) | 0.195 | 14 (41.2%) | 20 (58.8%) | 0.531 |
| 1 | 105 (45.7%) | 125 (54.3%) | 100 (43.5%) | 130 (56.5%) | ||
| 2 | 215 (43.0%) | 285 (57.0%) | 233 (46.6%) | 267 (53.4%) | ||
| 3 or More | 57 (54.3%) | 48 (45.7%) | 54 (51.4%) | 51 (48.6%) | ||
| Primary Care provider | ||||||
| Yes | 97 (49.0%) | 101 (51.0%) | 0.223 | 107 (54.0%) | 91 (46.0%) | 0.012 |
| No | 294 (43.8%) | 377 (56.2%) | 294 (43.8%) | 377 (56.2%) | ||
| Index Case Details (Baseline, n = 399) | ||||||
| Cough Duration | n = 869 | n = 869 | ||||
| <2 weeks | 22 (37.9%) | 36 (62.1%) | 0.322 | 22 (37.9%) | 36 (62.1%) | 0.638 |
| 2–4 weeks | 78 (49.4%) | 80 (50.6%) | 74 (46.8%) | 84 (53.2%) | ||
| 4–8 weeks | 204 (43.3%) | 267 (56.7%) | 219 (46.5%) | 252 (53.5%) | ||
| >8 weeks | 87 (47.8%) | 95 (52.2%) | 86 (47.3%) | 96 (52.7%) | ||
| Cavity on CXR | n = 798 | n = 798 | ||||
| Present | 179 (46.0%) | 210 (54.0%) | 0.133 | 168 (43.2%) | 221 (56.8%) | 0.102 |
| Absent | 166 (40.6%) | 243 (59.4%) | 201 (49.1%) | 208 (50.9%) | ||
| Sputum Grading | n = 869 | n = 869 | ||||
| Negative | 168 (47.2%) | 188 (52.8%) | 0.556 | 177 (49.7%) | 179 (50.3%) | 0.181 |
| <2+ | 138 (43.7%) | 178 (56.3%) | 141 (44.6%) | 175 (55.4%) | ||
| 2+ & More | 85 (43.1%) | 112 (56.9%) | 83 (42.1%) | 114 (57.9%) | ||
| Smear & Culture | n = 869 | n = 869 | ||||
| C- S- | 65 (57.0%) | 49 (43.0%) | 0.045 | 64 (56.1%) | 50 (43.9%) | 0.102 |
| C- S+ | 3 (50.0%) | 3 (50.0%) | 2 (33.3%) | 4 (66.7%) | ||
| C+ S- | 103 (42.6%) | 139 (57.4%) | 113 (46.7%) | 129 (53.3%) | ||
| C+ S+ | 220 (43.4%) | 287 (56.6%) | 222 (43.8%) | 285 (56.2%) | ||
NA: not applicable. Questions about smoking and alcohol use were not asked and HbA1c for diabetes status was not done for participants <15 years of age. Employed: housewife, retired persons & student were included in the category ‘No’. HbA1c –Glycosylated Hemoglobin, Known DM–Self reported diabetes mellitus, CXR–Chest Xray, RBS–Random Blood Sugar