Table 8 Multivariable regression analyses of survival and major clinical outcomes

Survival analysis (Cox proportional hazards model)¹

KMC implementation

0.42 (HR)

0.28–0.63

<0.001

–

Gestational age (per week)

0.76 (HR)

0.68–0.85

<0.001

–

Birth weight (per 100 g)

0.82 (HR)

0.75–0.90

<0.001

–

Initial SAS score

1.28 (HR)

1.14–1.44

<0.001

–

Maternal age

0.98 (HR)

0.94–1.02

0.324

–

28-Day survival (logistic regression model)²

KMC (vs. standard care)

2.84 (OR)

1.96–4.12

<0.001

AUC = 0.86 (95% CI 0.82–0.90)³

Gestational age ≥ 32 weeks

2.16 (OR)

1.58–2.95

<0.001

–

Birth weight ≥ 1500 g

1.92 (OR)

1.44–2.56

<0.001

–

Initial SAS score < 5

1.68 (OR)

1.26–2.24

<0.001

–

Exclusive breastfeeding

1.54 (OR)

1.18–2.01

0.002

–

Nosocomial infection-free survival (logistic regression model)

KMC > 6 h/day

2.46 (OR)

1.82–3.32

<0.001

AUC = 0.82 (95% CI 0.78–0.86)

Birth weight (per 100 g)

1.28 (OR)

1.16–1.41

<0.001

–

CPAP duration < 4 days

1.76 (OR)

1.32–2.34

<0.001

–

Early feeding initiation

1.62 (OR)

1.24–2.12

<0.001

–

Early discharge success⁴ (logistic regression model)

KMC adherence > 80%

2.32 (OR)

1.74–3.09

<0.001

AUC = 0.84 (95% CI 0.80–0.88)

Weight gain > 15 g/kg/day

1.94 (OR)

1.46–2.58

<0.001

–

Exclusive breastfeeding

1.86 (OR)

1.42–2.44

<0.001

–

No infections

1.72 (OR)

1.28–2.31

<0.001

–

Length of stay (linear regression)⁵

KMC implementation

−5.84 (β)

−7.12, − 4.56

<0.001

R² = 0.64; Adjusted R² = 0.62

Gestational age

−2.16 (β)

−2.84, − 1.48

<0.001

–

Birth weight

−0.94 (β)

−1.28, − 0.60

<0.001

–

Nosocomial infection

4.86 (β)

3.42, 6.30

<0.001

–