Table 2. Demographic characters of study after 1:1 PSM.
| Chest tube (days) | Drainage time ≤2 days (N=429) | SD/% | Drainage time >2 days (N=429) | SD/% | P |
|---|---|---|---|---|---|
| Age (year) | 0.740 | ||||
| Mean | 59.61 | 10.2 | 60.88 | 10.5 | |
| Gender | 0.166 | ||||
| Male | 240 | 55.9 | 260 | 60.6 | |
| Female | 189 | 44.1 | 169 | 39.4 | |
| FVC (L) | 0.642 | ||||
| Mean | 2.98 | 1.0 | 2.95 | 1.0 | |
| FEV1 (L) | 0.073 | ||||
| Mean | 2.27 | 0.8 | 2.17 | 0.8 | |
| CT-diameter (cm) | 0.032 | ||||
| Mean | 2.97 | 1.5 | 3.12 | 1.6 | |
| Smoking | 0.148 | ||||
| Yes | 134 | 31.2 | 154 | 35.9 | |
| No | 295 | 68.8 | 275 | 64.1 | |
| Family history | 0.738 | ||||
| Yes | 4 | 0.9 | 5 | 1.2 | |
| No | 425 | 99.1 | 424 | 98.8 | |
| Basic disease | 1.000 | ||||
| Yes | 136 | 31.7 | 136 | 31.7 | |
| No | 293 | 68.3 | 293 | 68.3 | |
| Comorbidity | 0.873 | ||||
| Yes | 20 | 4.7 | 21 | 4.9 | |
| No | 409 | 95.3 | 408 | 95.1 | |
| Surgical approach | 0.208 | ||||
| Lobectomy | 400 | 93.2 | 408 | 95.1 | |
| Wedge resection | 29 | 6.8 | 21 | 4.9 | |
| Blood | 0.160 | ||||
| A | 104 | 24.2 | 132 | 30.8 | |
| B | 122 | 28.4 | 112 | 26.1 | |
| O | 167 | 38.9 | 147 | 34.3 | |
| AB | 36 | 8.4 | 38 | 8.9 | |
| Tumor position | 0.638 | ||||
| Right upper | 134 | 31.2 | 137 | 31.9 | |
| Right middle | 36 | 8.4 | 41 | 9.6 | |
| Right lower | 71 | 16.6 | 83 | 19.3 | |
| Left upper | 121 | 28.2 | 107 | 24.9 | |
| Left lower | 67 | 15.6 | 60 | 14.0 | |
| Pathology | 0.014 | ||||
| Squamous cell carcinoma | 35 | 8.2 | 57 | 13.3 | |
| Adenocarcinoma | 365 | 85.1 | 332 | 77.4 | |
| Others | 29 | 6.8 | 40 | 9.3 | |
| Pathological staging | 0.003 | ||||
| I | 300 | 69.9 | 260 | 60.6 | |
| II | 44 | 10.3 | 50 | 11.7 | |
| III | 78 | 18.2 | 96 | 22.4 | |
| IV | 7 | 1.6 | 23 | 5.4 |
PSM, propensity score matching; SD, standard deviation; FVC, forced vital capacity; FEV1, forced expiratory volume in 1 second; CT, computed tomography.