Table 3.

Association between conditional variables and neurodevelopmental delay at six months old in girls

Conditional variables at birth and 4 months old	Total	Communication	Gross motor	Fine motor	Problem solving	Personal-Social
	2,432/30,358 (8.0 %)	584/30,504 (1.9 %)	468/30,505 (1.5 %)	743/30,436 (2.4 %)	1,113/30,510 (3.6 %)	290/30,476 (1.0 %)
Length at birth	0.99 (0.95–1.05)	1.04 (0.93–1.16)	1.12 (0.99–1.26)	0.98 (0.89–1.07)	0.96 (0.89–1.04)	0.90 (0.78–1.05)
Weight at birth	0.93 (0.88–0.98)	0.93 (0.84–1.04)	0.83 (0.73–0.94)	0.96 (0.87–1.06)	0.95 (0.88–1.02)	0.94 (0.81–1.10)
cLength at 4 months old	0.87 (0.83–0.91)	0.86 (0.78–0.94)	0.89 (0.81–0.99)	0.88 (0.81–0.96)	0.83 (0.78–0.89)	0.80 (0.72–0.91)
crWeight at 4 months old	1.05 (0.99–1.11)	0.92 (0.82–1.03)	1.44 (1.26–1.63)	0.99 (0.89–1.10)	0.99 (0.91–1.07)	1.14 (0.97–1.34)

Data represent the adjusted relative risk (95 % confidence interval). All of the conditional variables and the following covariates were included together in the model: maternal age and smoking, maternal and paternal education, family income, and home speech stimulation.

cLength conditional length; crWeight conditional relative weight