Table 1 Patient characteristics.
Variable | Derivation cohort n = 480 (%) | Validation cohort n = 240 (%) | p value |
|---|---|---|---|
Age, years (mean ± SD) | 23–86 (66 ± 10) | 38–87 (67 ± 10) | 0.245 |
Sex, male | 236 (49) | 122 (51) | 0.673 |
Any smoking history | 271 (57) | 146 (61) | 0.262 |
Comorbidities, present | 227 (47) | 132 (55) | 0.051 |
FEV1.0, L (mean ± SD) | 0.98–4.93 (2.36 ± 0.67) | 0.89–4.93 (2.28 ± 0.64) | 0.125 |
FEV1.0% (mean ± SD) | 39–96 (73 ± 9) | 35–93 (73 ± 10) | 0.795 |
Clinical stage | (0-IA2 vs. IA3) 0.163 | ||
0 | 32 (7) | 13 (6) | |
IA1 | 94 (20) | 43 (18) | |
IA2 | 201 (42) | 95 (40) | |
IA3 | 153 (32) | 89 (37) | |
Pathological stage | (I vs. II-III) 0.234 | ||
IA | 312 (65) | 164 (68) | |
IB | 92 (19) | 46 (19) | |
II | 40 (8) | 16 (7) | |
III | 36 (8) | 14 (6) | |
Histology | 0.274 | ||
Adenocarcinoma | 422 (88) | 204 (85) | |
Others | 58 (12) | 36 (15) | |
Pathological lymph-node status | (N0 vs. N1-3) 0.869 | ||
N0 | 420 (88) | 213 (89) | |
N1 | 25 (5) | 13 (5) | |
N2 | 31 (7) | 14 (6) | |
N3 | 4 (1) | 0 | |
Surgical procedure | 0.008 | ||
Lobectomy | 430 (90) | 229 (95) | |
Segmentectomy | 50 (10) | 11 (5) | |
