| Hospitalization duration per day | Occurrence of SSI | TOTAL | p-value | |
| YES | NO | |||
| ≤10 | 2.0% (1) | 85.1% (86) | 57.2% (87) | p = 0.0005 |
| ]10 - 20] | 43.1% (22) | 13.9% (14) | 23.7% (36) | |
| ]20 - 30] | 29.4% (15) | 1.0% (1) | 10.5% (16) | |
| >30 | 25.5% (13) | 0.0% (0) | 8.6% (13) | |
| TOTAL | 100% (51) | 100% (101) | 100% (152) | |