Table 2.
Univariate and Multivariate Analyses of Known Smear-Positive Associates and Derivation of a Clinical Prediction Score
| Univariate Analysis |
||||
| Odds Ratio (95% CI) | P Value | |||
| Demographic factors | ||||
| Age | 0.97 (.94–1.00) | .17 | ||
| Male sex | 2.67 (1.18–6.03) | .02 | ||
| HIV-infected | 0.39 (.16–.91) | .03 | ||
| Previous Tuberculosis | 0.51 (1.19–1.34) | .17 | ||
| Smoker (past or current) | 1.21 (.51–2.92) | .67 | ||
| Symptoms | ||||
| Hemoptysis | 0.53 (.19–1.51) | .23 | ||
| Weight loss | 10.88 (3.16–37.4) | <.01 | ||
| Appetite loss | 2.00 (.89–4.48) | .09 | ||
| Chest radiography | ||||
| Compatible with active Tuberculosis | 0.22 (.05–.01) | .05 | ||
| Presence of cavities | 13.42 (2.92–61.54) | <.01 | ||
| Xpert MTB/RIF–specific factors | ||||
| Average CT value | 0.75 (.68–.83) | <.01 | ||
| Sample volume used (mL) | 1.00 (.99–1.00) | .30 | ||
| Multivariate Analysis | ||||
| Odds Ratio (95% CI) | P Value | β-Coefficient (95% CI) | Scoreb | |
| Male sex | 2.16 (.43–10.74) | .35 | .77 (−.83 to 2.37) | N/Aa |
| HIV-infected | 0.85 (.24–2.92) | .79 | −.17 (−1.41 to 1.07) | N/Aa |
| Weight loss | 9.51 (1.05–90.07) | .05 | 2.25 (.00–4.5) | −3 |
| Presence of cavities | 4.07 (.70–23.53) | .12 | 1.4 (−0.35 to 3.16) | N/Aa |
| Average CT value | 0.72 (.60–.85) | <.001 | −.33 (−.51 to −.16) | .3 |
| Clinical prediction score formula | 0.3 × (average CT value) – 3 × (1 if self-reported weight loss occurred; 0 if no self-reported weight loss occurred) | |||
Abbreviations: CI, confidence interval; CT, cycle-threshold; HIV, human immunodeficiency virus.
a
Not included in final model as not significant (P ≥ .05).
b
Based on the β-coefficient in the final model.