Table 1.
Impact of demographic factors on buccal Ld
| Demographic information |
Testing set | Validation set | Nonsmoking controls (n = 22) |
Smoking controls (n = 12) |
||||||
|---|---|---|---|---|---|---|---|---|---|---|
| COPD (n = 18) |
Cancer (n = 36) |
COPD vs. cancer (P) |
Effect of Ld (P) |
COPD (n = 19) |
Cancer (n = 27) |
COPD vs. cancer (P) |
Effect of Ld (P) |
|||
| Age (mean ± SO), pack years |
72 ± 10 | 69 ± 12 | 0.38 | 0.73 | 71 ± 8 | 71 ± 13 | 0.96 | 0.55 | 64 ± 12 | 50 ± 14 |
| Smoking (mean ± SO), pack years |
63 ± 32 | 59 ±27 | 0.73 | 0.95 | 65 ± 34 | 51 ± 36 | 0.17 | 0.62 | N/A | 23 ± 24 |
| Race (% white) | 95 | 92 | 0.98 | 0.41 | 95 | 85 | 0.27 | 0.10 | 100 | 75 |
| Gender (% male) | 61 | 44 | 0.26 | 0.90 | 50 | 48 | 0.65 | 0.88 | 36 | 50 |
NOTE: Demographic characteristics such as age, smoking history, race, and gender is shown for different patient groups and their effect on Ld. The P value is calculated using the analysis of covariance analysis in STATA. The data indicate that the diagnostic information calculated in the testing and validation set is not confounded by the patient demographic factors. The data also indicate that the demographic factors are not significant between COPD and cancer patients in both the training and validation set.