Table 4. Primary and Secondary Outcomes of Patients in the MOABP and MBP Plus Placebo Groups.
| Outcome | No. (%) | Effect size | P valuea | ||
|---|---|---|---|---|---|
| MBP plus placebo (n = 288) | MOABP (n = 277) | OR (95% CI) | Wilcoxon effect size | ||
| Comprehensive Complication Indexb | |||||
| Mean (SD) | 12.3 (15.3) | 8.3 (13.9) | |||
| Median (IQR) | 8.66 (0-20.92) | 0 (0-8.66) | NA | 0.146 | <.001 |
| Surgical site infection | 48 (16.7) | 23 (8.3) | 0.45 (0.27-0.77) | NA | .003 |
| Superficial incisional | 5 (1.7) | 6 (2.2) | NA | NA | |
| Deep incisional | 0 | 0 | NA | NA | |
| Organ or space | 43 (14.9) | 17 (6.1) | NA | NA | |
| Anastomotic dehiscencec | 39 (13.5) | 16 (5.8) | 0.39 (0.21-0.72) | NA | .002 |
| Grade A | 22 (7.6) | 5 (1.8) | NA | NA | |
| Grade B | 5 (1.7) | 3 (1.1) | NA | NA | |
| Grade C | 12 (4.2) | 8 (2.9) | NA | NA | |
| Length of hospital stay, median (IQR), db | 6 (5-8)d | 6 (5-7)e | NA | 0.050 | .23 |
| Mortality within 90 d after surgery | 2 (0.7) | 3 (1.1) | 1.57 (0.26-9.44) | NA | .68f |
| No. of patients receiving adjuvant treatment/total No. of patients requiring adjuvant treatmentg | 94/108 (87) | 96/110 (87) | 0.98 (0.44-2.17) | NA | .96 |
Abbreviations: MBP, mechanical bowel preparation; MOABP, mechanical and oral antibiotics bowel preparation; NA, not applicable; OR, odds ratio.
With Bonferroni correction, P < .01 is considered statistically significant for secondary outcomes.
Comprehensive Complications Index and length of hospital stay were not normally distributed, and hence effect size is given as Wilcoxon effect size (r = Z / [square root of N]) without 95% CIs and the P value is calculated using Mann-Whitney U test. Wilcoxon effect size of 0.1 is considered as a small effect, 0.3 as a moderate effect, and 0.5 and above as a large effect. The mean (SD) Comprehensive Complication Index is shown, but no statistical testing for mean difference was performed as it was not normally distributed.
Grade A: anastomotic dehiscence resulting in no change in patient’s management; grade B: dehiscence requiring active therapeutic intervention but no repeat laparotomy; grade C: anastomotic dehiscence requiring repeat laparotomy or laparoscopy.
Data for 1 patient were excluded (died during hospital stay).
Data for 2 patients were excluded (died during hospital stay).
Fisher exact test.
The criteria for adjuvant treatment were pathologic nodal positivity, lymphovascular invasion, high tumor budding, or high-grade adenocarcinoma.