Table 3.
Proportions of patients with SSI according to different factors
| Surgical site infection | |||
|---|---|---|---|
| Rates | Group differences | ||
| % | χ2 | P | |
| Age band (years) | |||
| 18.3–29.9 | 7.7 | 1.1 | 0.571 |
| 30–39.9 | 6.4 | ||
| 40–54.6 | 8.0 | ||
| Ethnicity | |||
| White British | 6.8 | 1.1 | 0.573 |
| Ethic minority groupsa | 6.8 | ||
| Not recorded | 10.3 | ||
| Smoking history | |||
| Never smokers | 6.2 | 6.6 | 0.010 |
| Former/current smokers | 10.6 | ||
| BMI (kg/m2) | |||
| < 30 | 0.9 | 8.9 | 0.003 |
| 30–34.9 | 2.5 | ||
| ≥ 35 | 3.2 | ||
| Diabetes status | |||
| No history of diabetes | 6.7 | 0.6 | 0.425 |
| Diabetes mellitusb | 8.0 | ||
| Previous C-section | |||
| None | 6.3 | 2.7 | 0.062 |
| Yes | 8.5 | ||
| Admission type | |||
| Elective | 6.5 | 0.5 | 0.279 |
| Emergency C-section | 7.4 | ||
| Pre-operative antimicrobial prophylaxis | |||
| Yes | 6.2 | 0.3 | 0.352 |
| No | 7.0 | ||
| Post-operative antimicrobial prophylaxis or treatment | |||
| Yes | 7.7 | 0.6 | 0.257 |
| No | 6.6 | ||
| Vaginal cleansing | |||
| Yes | 5.7 | 3.3 | 0.043 |
| No | 7.9 | ||
aAfro-Caribbeans or Africans, South Asians, mixed race, and other ethnicities. bGestational diabetes controlled by diet or drugs, and Type 1 or type 2 diabetes