Table 4:
Sensitivity and subgroup analyses to assess the role of negative TST on all-cause mortality during TB treatment among adult patients with culture-confirmed TB, Georgia, 2009 – 2014
| No | Various Sensitivity Analyses | Measure of Association | TST Results | Crude Estimates | Adjusted Estimates* |
|---|---|---|---|---|---|
| 1 | TST Misclassification (N=1186) | ||||
| Including patients with invalid TST results | Risk ratio (95% CI) | TST Not Done TST Negative TST Positive |
3.94 (2.32 –
6.68) 3.21 (1.80 – 5.74) Reference |
2.64 (1.51 –
4.63) 2.21 (1.19 – 4.09) Reference |
|
| Patients with TST missing/not done classified as TST negative | Risk ratio (95% CI) | TST Negative TST Positive |
3.64 (2.20 –
6.02) Reference |
2.47 (1.45 –
4.20) Reference |
|
| Patients with TST missing/not done classified as TST positive | Risk ratio (95% CI) | TST Negative TST Positive |
1.49 (0.97 –
2.30) Reference |
1.28 (0.81 –
2.03) Reference |
|
| TST induration classification | Risk Ratio (95% CI) | 0 mm 1 – 10 mm > 10 mm |
2.73 (1.49 – 5.01) 0.85 (0.20 – 3.57) Reference |
1.95 (1.01 –
3.79) 0.88 (0.20 – 3.91) Reference |
|
| 2 | Unmeasured confounding† (N=780) | ||||
| Externally adjusted for smoking | Risk ratio range | TST Negative TST Positive |
3.27 – 5.38 Reference |
||
| Externally adjusted for treatment adherence | Risk ratio range | TST Negative TST Positive |
2.84 – 7.05 Reference |
||
| Externally adjusted for CD4 count suppression (among n=86 patients with HIV) | Risk Ratio Range | TST Negative TST Positive |
0.49 – 1.50 Reference |
||
| 3 | Model Specification (N=773) | ||||
| Cox proportional hazard model | Hazard rate ratio (95% CI) | TST Negative TST Positive |
2.65 (1.39 –
5.04) Reference |
2.08 (1.05 –
4.12) Reference |
|
| 4 | Covariate misspecification | ||||
| Multiple log-binomial logistic regression models1 (N=780) | Risk ratio range | TST Negative TST Positive |
2.10 – 2.37 Reference |
||
| Multiple Cox proportional hazard regression models2 (N=773) | Hazard rate ratio range | TST Negative TST Positive |
1.72 – 2.15 Reference |
*
Adjusted for age, gender, HIV, diabetes, ESRD, cavitary disease, miliary disease, alcohol abuse, and foreign-born status
†
Range of risk ratio was calculated using 2×2 table according to Lash et al. [23]
1
Results were available in Supplemental Table 3
2
Results were available in Supplemental Table 4