Table 3.
Association of clinical variables with invasive procedures
| Multivariate Model | ||
|---|---|---|
| Predictor Variable | Minor or Major Procedure | |
| Risk Ratio | 95% CI | |
| Age, yr | ||
| 44 | 0.97 | 0.94, 0.99 |
| 53 | 0.99 | 0.96, 1.02 |
| 62 | Ref. | — |
| 71 | 0.98 | 0.95, 1.00 |
| 80 | 0.91 | 0.88, 0.94 |
| Smoking history, pack-years | ||
| 0 | Ref. | — |
| 12 | 1.13 | 1.10, 1.16 |
| 24 | 1.14 | 1.11, 1.17 |
| 36 | 1.17 | 1.14, 1.20 |
| Nodule size, mm | ||
| 6 | 0.79 | 0.77, 0.82 |
| 10 | Ref. | — |
| 14 | 1.07 | 1.04, 1.10 |
| 18 | 1.16 | 1.12, 1.19 |
| 22 | 1.20 | 1.16, 1.23 |
| Hypothetical test | ||
| No test | Ref. | — |
| Low risk | 0.91 | 0.89, 0.94 |
| Indeterminate | 1.07 | 1.04, 1.10 |
| High risk | 1.21 | 1.18, 1.25 |
Definition of abbreviation: CI = confidence interval; Ref = reference.