Table 2 Univariate analysis of risk factors for organ-space surgical site infection in colon and rectal surgery

Age, median (IQR) years

70 (61–79)

73 (63–79)

0.3

68 (60–76)

66.5 (58–74)

0.07

Age ≥ 65 years, (%)

67.6

72

0.2

61.5

58.8

0.5

Male sex, (%)

58.4

70

0.001

65.4

80.9

<0.001

ASA ≥ III, (%)

41.9

45.5

0.3

36.1

41.2

0.25

Correct IV antibiotic prophylaxis, (%)

84.3

81.5

0.3

81.4

83.8

0.5

Duration of operation ≥ p75th^a, (%)

37.5

39

0.7

41.2

54.4

0.003

Laparoscopy, (%)

61.6

44

<0.001

66.3

64.7

0.7

NNIS ≥ 1, (%)

35.5

43

0.03

32.7

41.2

0.05

Neoplasia, (%)

93.6

93

0.7

97.2

94.9

0.13

Inflammatory bowel disease, (%)

2.9

4

0.38

1.1

2.9

0.1

Chemotherapy, (%)

3.1

3.5

0.7

45.1

45.2

1

Radiotherapy, (%)

1.2

2.5

0.18

46

47.4

0.7

Oral antibiotic prophylaxis, (%)

43.7

33

0.004

43.3

26.5

<0.001

Mechanical bowel preparation, (%)

71.4

67.2

0.2

89.1

90.4

0.6

Ostomy, (%)

7.3

20

<0.001

63.8

65.2

0.7