Table 1.

Characteristics of the study patients between the 2 phases

Characteristic	Phase I (n=315) (1998–2007)	Phase II (n=426) (2008–2017)	P value
Gestational age	31+3 (23+0–42+1)	30+3 (22+3–40+0)
<26 weeks	40/315 (12.7)	89/426 (20.9)	0.004a)
26–35 weeks	153/315 (48.6)	197/426 (32.9)	<0.001a)
≥35 weeks	122/315 (38.7)	140/426 (32.9)	0.099a)
Male sex	173/315 (54.9)	229/426 (53.8)	0.753a)
Birth weight (g)	1,468 (469–4,900)	1,290 (282–4,125)
<1,500	160/315 (50.8)	246/426 (57.7)	0.060a)
1,500–2,500	58/315 (18.4)	73/426 (17.1)	0.652a)
≥2,500	97/315 (30.8)	107/426 (25.1)	0.087a)
Delivery mode (cesarean section)	191/315 (60.6)	294/426 (69.0)	0.018a)
Inborn	226/315 (71.7)	407/426 (85.4)	<0.001a)
Multiple gestation	30/315 (9.5)	174/426 (27.5)	<0.001a)

Values are presented as median (range) or number (%).

^a)Indicating chi-square test.

Boldface indicates a statistically significant difference with P<0.05.