Table 1 Baseline demographic and clinical characteristics of study participants

Infant characteristics

- Gestational age (weeks)²

32.1 (1.5) [1]³

32.0 (1.6) [2]

0.06 (−0.19, 0.31)

0.71

Gestational age category, n (%)

0.02 (−0.18, 0.22)

0.70

- 28–31 weeks

40 (33.3)

42 (35.0)

- 32–34 weeks

80 (66.7)

78 (65.0)

- Birth weight (g)²

1450.2 (135.3) [1]

1448.3 (137.6) [1]

0.01 (−0.24, 0.26)

0.85

- Birth weight category, n (%)

0.03 (−0.17, 0.23)

0.82

- 1000–1499 g

72 (60.0)

70 (58.3)

- 1500–1999 g

48 (40.0)

50 (41.7)

Sex, n (%)

0.03 (−0.17, 0.23)

0.88

- Male

64 (53.3)

62 (51.7)

- Female

56 (46.7)

58 (48.3)

Maternal characteristics

- Maternal age (years)²

28.3 (4.1) [2]

28.5 (3.9) [3]

0.05 (−0.20, 0.30)

0.79

- Parity²

1.2 (1.0) [3]

1.3 (1.1) [2]

0.09 (−0.16, 0.34)

0.66

- Maternal hypertension, n (%)

25 (20.8) [1]

27 (22.5)

0.04 (−0.16, 0.24)

0.72

- Mode of delivery, n (%)

0.05 (−0.15, 0.25)

0.75

- Vaginal

82 (68.3)

80 (66.7)

- Cesarean section

38 (31.7)

40 (33.3)

Clinical parameters

- Baseline SAS score²

4.2 (1.0) [1]

4.3 (0.9) [1]

0.10 (−0.15, 0.35)

0.63

- Apgar score at 5 min²

7.5 (1.2) [2]

7.4 (1.3) [1]

0.08 (−0.17, 0.33)

0.68

Initial respiratory support, n (%)

- Room air only

18 (15.0)

20 (16.7)

0.04 (−0.16, 0.24)

0.84

- Low-flow oxygen

55 (45.8)

52 (43.3)

0.05 (−0.15, 0.25)

0.75

- CPAP

47 (39.2)

48 (40.0)

0.01 (−0.19, 0.21)

0.91

Vital signs at admission⁴

- Temperature (°C)²

36.8 (0.3) [1]

36.7 (0.4) [2]

0.28 (−0.03, 0.53)

0.12

- Heart rate (beats/min)²

142.5 (12.3) [1]

143.2 (11.8) [2]

0.06 (−0.19, 0.31)

0.77

- Respiratory rate (breaths/min)²

52.4 (8.2) [2]

51.8 (8.5) [1]

0.07 (−0.18, 0.32)

0.74

- SpO₂ (%)

92.5 (2.8) [1]

92.3 (2.9) [1]

0.07 (−0.18, 0.32)

0.75

Initial treatment

- IV antibiotics, n (%)

105 (87.5) [1]

106 (88.3) [2]

0.02 (−0.18, 0.22)

0.85

- IV fluids, n (%)

107 (89.2)

100 (83.3)

0.17 (−0.03, 0.37)

0.18

- Vitamin K administration, n (%)

120 (100.0)

120 (100.0)

NA

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