Table 1.
Demographic, Clinical, and Biomarker Characteristics Stratified by Cancer Status or membership in the training and test sets. Data are means ± standard deviations for continuous variables and proportions with percentages for dichotomous variables.
| Factor | Overall (n = 163) | Cancer (n = 78) | No Cancer (n = 85) | p† | Train (n=76) | Test (n=62) | p† |
|---|---|---|---|---|---|---|---|
| Age | 58.1 ± 14.3 | 64.5 ± 9.6 | 52.3 ± 15.4 | < 0.001 | 57.3 ± 14.0 | 57.5 ± 15.3 | 0.91 |
| Male | 122/163 (74.8) | 60/78 (76.9) | 62/85 (72.9) | 0.59 | 59/76 (77.6) | 42/62 (67.7) | 0.25 |
| Caucasian | 110/163 (67.5) | 67/78 (85.9) | 43/85 (50.6) | < 0.001 | 52/76 (68.4) | 36/62 (58.1) | 0.22 |
| Smoked Within 10 Years | 130/163 (79.8) | 60/78 (76.9) | 70/85 (82.4) | 0.44 | 62/76 (81.6) | 47/62 (75.8) | 0.53 |
| Pack Years | 44.9 ± 32.0 | 54.9 ± 26.8 | 35.7 ± 33.7 | < 0.001 | 45.8 ± 30.2 | 39.9 ± 35.4 | 0.3 |
| Diagnostic Bronchoscopy | 45/163 (27.6) | 40/78 (51.3) | 5/85 (5.9) | < 0.001 | 20/76 (26.3) | 0/62 (0) | <0.001 |
| Cancer | 78/163 (47.9) | 78/78 (100.0) | 0/85 (0.0) | < 0.001 | 40/76 (52.6) | 17/62 (27.4) | 0.003 |
| Lymphadenopathy | 43/163 (26.4) | 36/78 (46.2) | 7/85 (8.2) | < 0.001 | 17/76 (22.4) | 10/62 (16.1) | 0.4 |
| Hemoptysis | 15/163 (9.2) | 6/78 (7.7) | 9/85 (10.6) | 0.6 | 10/76 (13.2) | 2/62 (3.2) | 0.07 |
| Mass Size > 3 cm | 48/163 (29.4) | 43/78 (55.1) | 5/85 (5.9) | < 0.001 | 24/76 (31.6) | 10/62 (16.1) | 0.047 |
| Biomarker | −0.35 ± 8.93 | 4.65 ± 7.04 | −4.94 ± 7.98 | < 0.001 | 0.34 ± 8.97 | −2.72 ± 9.12 | 0.05 |
†
p-values are for the comparison of patients with cancer and patients without cancer. Two-sample t-tests with unequal variances were used for continuous variables; Fisher’s exact test was used for dichotomous variables.