Baseline characteristics of the patients
| Characteristic | With wound drain (group 1, n=99) | Without wound drain (group 2, n=213) | P value |
| Age at surgery (years) (mean±SD) | 58.5±9.7 | 55.4±11.5 | |
| BMI at surgery (kg/m2) (mean±SD) | 23.2±3.5 | 23.3±3.6 | |
| Comorbidities (n (%)) | |||
| Hypertension | 23 (23.2) | 52 (24.4) | 0.820 |
| Diabetes mellitus | 10 (10.1) | 14 (6.6) | 0.276 |
| Smoking | 2 (2.0) | 1 (0.5) | 0.191 |
| ASA score (n (%)) | 0.001 | ||
| 1 | 10 (10.1) | 51 (23.9) | |
| 2 | 45 (45.5) | 106 (49.8) | |
| 3 | 44 (44.4) | 55 (25.8) | |
| 4 | 0 (0) | 1 (0.5) | |
| Previous abdominal surgery (n (%)) | 66 (66.7) | 102 (47.9) | 0.002 |
| Previous radiation (n (%)) | 2 (2.0) | 2 (0.9) | 0.594 |
BMI, body mass index; ASA, American Society of Anesthesiologists.