Multiple logistic regression analysis of risk factors predicting radiological progression
| Risk factors |
Parameter estimate | SE | p Value | OR (95% CI) |
| Model 1 (saturated model with forced variables): | ||||
| Age at initial chestx ray film | −0.0202 | 0.028 | NS | 0.98 (0.93 to 1.03) |
| Interval between chest x ray films (y) | 0.2390 | 0.071 | p=0.001 | 1.27 (1.10 to 1.46) |
| Profusion category at initial chestx ray film: | ||||
| Category 1 | Reference | 1.00 | ||
| Category 2 | 0.7080 | 0.464 | NS | 2.03 (0.88 to 4.70) |
| Category 3 or complicated3-150 | 1.3987 | 0.569 | p=0.01 | 4.05 (1.34 to 12.23) |
| Duration of exposure (y) | −0.0100 | 0.026 | NS | 0.99 (0.95 to 1.05) |
| History of pulmonary tuberculosis | 0.6729 | 0.439 | NS | 1.96 (0.83 to 4.64) |
| Ever smoker | −0.4463 | 0.537 | NS | 0.64 (0.22 to 1.84) |
| Time since exposure ended to latest chest x ray film (y) | −0.0726 | 0.037 | NS | 0.93 (0.87 to 1.01) |
| Model 2 (stepwise selection model with significant factors only): | ||||
| Interval between chest x ray films (y) | 0.1772 | 0.0572 | p=0.02 | 1.19 (1.07 to 1.34) |
| Profusion category at initial chestx ray film: | ||||
| Category 1 | Reference | 1.00 | ||
| Category 2 | 0.6374 | 0.4398 | NS | 1.89 (0.80 to 4.48) |
| Category 3 or complicated3-150 | 1.608 | 0.566 | p=0.005 | 4.99 (1.65 to 15.14) |
↵3-150 All cases with category 3 profusion also had large opacitioes.