Distribution of patient characteristics between derivation and validation sets
| Variables | Derivation set (n=1,420) | Validation set (n=1,229) | P-value |
|
|---|---|---|---|---|
| Age, yr | 60.1±11.3 | 62.4±11.5 | <0.0001 | |
| Sex | Male | 878 (61.83) | 868 (70.63) | <0.0001 |
| Female | 542 (38.17) | 361 (29.37) | ||
| Preop BMI, kg/m2 | 24.0±3.2 | 23.9±3.4 | 0.4364 | |
| Preop malnutrition, BMI <18.5 kg/m2 | No | 1,376 (96.90) | 1,178 (95.85) | 0.1468 |
| Yes | 44 (3.10) | 51 (4.15) | ||
| Surgical approach | Open | 392 (27.61) | 335 (27.26) | <0.0001 |
| Laparoscopy | 914 (64.37) | 846 (68.84) | ||
| Robot | 114 (8.03) | 48 (3.91) | ||
| Operation type | TG | 308 (21.69) | 245 (19.93) | <0.0001 |
| PG | 17 (1.20) | 18 (1.46) | ||
| DG | 834 (58.73) | 952 (77.46) | ||
| PPG | 261 (18.38) | 14 (1.14) | ||
| Reconstruction | RY (E-J) | 308 (21.69) | 245 (19.93) | <0.0001 |
| E-G | 5 (0.35) | 2 (0.16) | ||
| DT | 12 (0.85) | 16 (1.30) | ||
| B I | 559 (39.37) | 198 (16.11) | ||
| B II | 180 (12.68) | 672 (54.68) | ||
| RY (G-J) | 95 (6.69) | 82 (6.67) | ||
| G-G | 261 (18.38) | 14 (1.14) | ||
| Gastric cancer stage | I | 1,022 (71.97) | 863 (70.22) | 0.0396 |
| II | 173 (12.18) | 190 (15.46) | ||
| III | 225 (15.85) | 176 (14.32) | ||
| Adjuvant chemotherapy | No | 1,058 (74.51) | 866 (70.46) | 0.0199 |
| Yes | 362 (25.49) | 363 (29.54) | ||
| Complication | No | 1,059 (74.58) | 1,079 (87.79) | <0.0001 |
| Yes | 361 (25.42) | 150 (12.21) | ||
| Surgical mortality (within 30 days) | No | 1,420 (100) | 1,229 (100) | |
| Yes | 0 | 0 | ||
| Preop hemoglobin (11.5~15.5 g/dL) | 13.5±1.8 | 13.4±2.1 | 0.0546 | |
| Preop protein (6.0~8.2 g/dL) | 7.1±0.6 | 7.0±0.7 | 0.0015 | |
| Preop albumin (3.5~5.2 g/dL) | 4.2±0.4 | 4.3±0.6 | 0.0011 | |
| Preop cholesterol (120~220 mg/dL) | 185.5±39.4 | 176.9±40.9 | <0.0001 | |
Values are presented as mean±standard deviation or number (%).
Preop = preoperative; BMI = body mass index; TG = total gastrectomy; PG = proximal gastrectomy; DG = distal gastrectomy; PPG = pylorus-preserving gastrectomy; RY (E-J) = Roux-en-Y (esophago-jejunostomy); E-G = esophago-gastrostomy; DT = double tract; B = Billroth; RY (G-J) = Roux-en-Y (gastro-jejunostomy); G-G = gastro-gastrostomy.
aP-value calculated by chi-squared test for categorical variables and independent t-test for continuous variables.