Table 1.
Patient characteristics and operative outcomes before and after propensity score matching with multiple imputation and complete cases.
| Before PSM | PSM with MI | PSM with CC | |||||||
|---|---|---|---|---|---|---|---|---|---|
| OPG | ORG | P value | OPG | ORG | P value | OPG | ORG | P value | |
| N | 94 | 144 | 73 | 73 | 70 | 70 | |||
| Sex, malea | 61 (64.9) | 105 (72.9) | 0.24 | 50 (68.5) | 48 (65.8) | 0.86 | 48 (68.6) | 46 (65.7) | 0.86 |
| Agea | 67.0 (38–94) | 67.0 (37–90) | 0.73 | 67.0 (41–94) | 69.0 (37–90) | 0.66 | 66.5 (42–94) | 65.0 (37–90) | 0.76 |
| NACa | 7 (7.4) | 19 (13.2) | 0.24 | 5 (6.8) | 8 (11.0) | 0.56 | 5 (7.1) | 7 (10.0) | 0.76 |
| Conversion surgerya | 0 (0.0) | 3 (2.1) | 0.42 | 0 (0.0) | 0 (0.0) | 1.00 | 0 (0.0) | 0 (0.0) | 1.00 |
| Alba | 4.1 (2.4–5.2) | 4.1 (2.1–5.2) | 0.69 | 4.0 (2.4–5.2) | 4.0 (2.1–4.9) | 0.96 | 4.0 (2.4–5.2) | 4.12 (2.1–4.9) | 0.27 |
| Hba | 12.8 (5.0–17.1) | 13.0 (5.3–18.0) | 0.54 | 12.7 (5.8–17.1) | 12.5 (5.3–17.7) | 0.71 | 12.7 (5.8–17.1) | 12.5 (5.0–17.7) | 0.83 |
| BMIa | 22.4 (16.4–32.6) | 22.2 (14.1–34.3) | 0.69 | 22.4 (16.4–32.6) | 22.2 (15.5–30.0) | 0.93 | 22.4 (16.4–32.6) | 22.2 (15.8–30.3) | 0.84 |
| ASA-PSa | |||||||||
| 1 | 11 (11.7) | 10 (6.9) | 0.43 | 6 (8.2) | 7 (9.6) | 0.92 | 6 (8.6) | 6 (8.6) | 1.00 |
| 2 | 70 (74.5) | 115 (79.9) | 56 (76.7) | 57 (78.1) | 53 (75.7) | 54 (77.1) | |||
| 3 | 13 (13.8) | 19 (13.2) | 11 (5.1) | 9 (12.3) | 11 (15.7) | 10 (14.3) | |||
| CCIa | |||||||||
| 0 | 68 (72.3) | 107 (74.3) | 0.56 | 54 (74.0) | 58 (79.5) | 0.95 | 51 (72.9) | 54 (77.1) | 1.00 |
| 1 | 18 (19.1) | 20 (13.9) | 12 (16.4) | 10 (13.7) | 12 (17.1) | 9 (12.9) | |||
| 2 | 2 (2.1) | 7 (4.9) | 2 (2.7) | 2 (2.7) | 2 (2.9) | 2 (2.9) | |||
| 3 | 4 (4.3) | 4 (2.8) | 3 (4.1) | 2 (2.7) | 3 (4.3) | 3 (4.3) | |||
| 4 | 1 (1.1) | 5 (3.5) | 1 (1.4) | 0 (0.0) | 1 (1.4) | 1 (1.4) | |||
| 5 | 1 (1.1) | 1 (0.7) | 1 (1.4) | 1 (1.4) | 1 (1.4) | 1 (1.4) | |||
| cTa | |||||||||
| 3 | 47 (50.0) | 51 (35.4) | < 0.05 | 32 (43.8) | 35 (47.9) | 0.74 | 30 (42.9) | 30 (42.9) | 1.00 |
| 4 | 47 (50.0) | 93 (64.6) | 41 (56.2) | 38 (52.1) | 40 (57.1) | 40 (57.1) | |||
| cNa | |||||||||
| 0 | 26 (27.7) | 14 (9.7) | < 0.05 | 13 (17.8) | 13 (17.8) | 0.93 | 13 (18.6) | 11 (15.7) | 0.89 |
| 1 | 21 (22.3) | 29 (20.1) | 17 (23.3) | 17 (23.3) | 16 (22.9) | 16 (22.9) | |||
| 2 | 23 (24.5) | 46 (31.9) | 22 (30.1) | 19 (26.0) | 20 (28.6) | 15 (40.0) | |||
| 3 | 24 (25.5) | 55 (38.2) | 21 (28.8) | 24 (32.9) | 21 (30.0) | 28 (20.0) | |||
| Tumour locationa | |||||||||
| Lower | 30 (31.9) | 39 (27.1) | 0.17 | 24 (32.9) | 24 (32.9) | 0.60 | 25 (35.7) | 25 (35.7) | 1.00 |
| Middle | 31 (33.0) | 66 (45.8) | 28 (38.4) | 33 (45.2) | 25 (35.7) | 26 (37.1) | |||
| Upper | 33 (35.1) | 39 (27.1) | 21 (28.8) | 16 (21.9) | 20 (28.6) | 19 (27.1) | |||
| Circumferencea | |||||||||
| Ant | 17 (18.1) | 29 (20.1) | 0.32 | 15 (20.5) | 14 (19.2) | 0.944 | 15 (21.4) | 12 (17.1) | 0.98 |
| Circ | 8 (8.5) | 25 (17.4) | 8 (11.0) | 11 (15.1) | 7 (10.0) | 8 (11.4) | |||
| Gre | 9 (9.6) | 14 (9.7) | 8 (11.0) | 6 (8.2) | 8 (11.4) | 7 (10.0) | |||
| Less | 43 (45.7) | 52 (36.1) | 31 (42.5) | 31 (42.5) | 30 (42.9) | 32 (45.7) | |||
| Post | 17 (18.1) | 24 (16.7) | 11 (15.1) | 11 (15.1) | 10 (14.3) | 11 (15.7) | |||
| Tumour typea | |||||||||
| 0 | 11 (11.7) | 11 (7.6) | 0.12 | 6 (8.2) | 7 (9.6) | 0.991 | 5 (7.1) | 6 (8.6) | 0.95 |
| 1 | 8 (8.5) | 8 (5.6) | 5 (6.8) | 5 (6.8) | 5 (7.1) | 3 (4.3) | |||
| 2 | 21 (22.3) | 30 (20.8) | 18 (24.7) | 16 (21.9) | 17 (24.3) | 15 (21.4) | |||
| 3 | 50 (53.2) | 74 (51.4) | 40 (54.8) | 40 (54.8) | 40 (57.1) | 43 (61.4) | |||
| 4 | 4 (4.3) | 14 (9.7) | 4 (5.5) | 5 (6.8) | 3 (4.3) | 3 (4.3) | |||
| 5 | 0 (0.0) | 7 (4.9) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | |||
| Operationa | |||||||||
| Total gastrectomy | 42 (44.7) | 60 (41.7) | 0.75 | 29 (39.7) | 26 (35.6) | 0.73 | 26 (37.1) | 25 (35.7) | 1.00 |
| Lymphadenectomya | |||||||||
| D2 or more | 70 (74.5) | 127 (88.2) | < 0.05 | 58 (79.5) | 64 (87.7) | 0.26 | 56 (80.0) | 61 (87.1) | 0.36 |
| Other organ resectiona | |||||||||
| Total | 10 (10.6) | 44 (30.6) | < 0.05 | 10 (13.7) | 8 (11.0) | 0.80 | 10 (14.3) | 10 (14.3) | 1.00 |
| Liver | 0 (0.0) | 1 (0.7) | 1.00 | 0 (0.0) | 0 (0.0) | 1.00 | 0 (0.0) | 0 (0.0) | 1.00 |
| Pancreas | 7 (7.4) | 9 (6.2) | 0.92 | 7 (9.6) | 3 (4.1) | 0.33 | 7 (10.0) | 1 (1.4) | 0.06 |
| Spleen | 9 (9.6) | 34 (23.6) | < 0.05 | 9 (12.3) | 7 (9.6) | 0.79 | 9 (12.9) | 9 (12.9) | 1.00 |
| Transverse colon | 1 (1.1) | 5 (3.5) | 0.46 | 0 (0.0) | 0 (0.0) | 1.00 | 0 (0.0) | 1 (1.4) | 1.00 |
| Transverse mesocolon | 0 (0.0) | 3 (2.1) | 0.42 | 1 (1.4) | 1 (1.4) | 1.00 | 1 (1.4) | 0 (0.0) | 1.00 |
| Laparoscopic resection | 63 (67.0) | 46 (31.9) | < 0.05 | 47 (64.4) | 30 (41.1) | < 0.05 | 45 (64.3) | 29 (41.4) | < 0.05 |
Data are expressed as the median (range) for continuous variables and the number of cases (%) for categorical variables.
PSM propensity score matching, MI multiple imputation, CC Complete cases, NAC neoadjuvant chemotherapy, Alb serum albumin level, Hb serum haemoglobin level, BMI body mass index, ASA-PS American Society of Anesthesiologists Physical Status, CCI Charlson Comorbidity Index, Ant anterior, Circ circular, Gre greater curvature, Less lesser curvature, Post posterior.
aIndicates covariates to calculate the propensity score.