Table 2 Univariate and multivariate analyses of factors potentially related to antibiotic prophylaxis-resistant surgical site infections (Logistic regression analysis; results expressed as odds ratios with 95% confidence intervals)

Female sex

1.0, 0.7–1.4

n.d.

Age

1.0, 1.0–1.0

1.0, 1.0–1.0

Past history of MRSA^b body carriage

1.3, 1.1–2.9

1.4, 1.1–3.3

Immune suppression^a

0.7, 0.5–1.1

n.d.

- Diabetes mellitus

0.7, 0.4–1.2

n.d.

Shoulder implants

0.5, 0.2–1.5

n.d.

Arthroplasties

1.1, 0.8–1.8

1.2, 0.8–1.9

Spondylodeses

1.4, 0.7–2.9

1.4, 0.6–3.1

Plates

1.0, 0.6–1.5

n.d.

Intramedullary nails

1.2, 0.6–2.3

1.3, 0.6–2.6

Foot osteosyntheses

0.7, 0.3–1.6

0.8, 0.3–1.9

Duration of prior hospital stay

1.0, 1.0–1.0

1.0, 1.0–1.0

- 10–20 days compared to ≤10 days

1.1, 0.5–2.4

1.2, 0.5–2.5

- ≥ 20 days compared to ≤10 days

1.0, 0.6–1.7

1.1, 0.4–3.3