Table 8.

Backward selection regression model: birthweight^a (n = 176)

Variables	Estimate (β)	Standard error	95% confidence limits		p-Value
Gestational age at birth (weeks)	33.80	7.90	18.29	49.31	<.001
Gestational age at birth * gestational age at birth (weeks)	−4.39	1.12	−6.58	−2.20	<.001
Infant sex (male = 0, female = 1)	−0.04	0.02	−0.08	−0	.037
Ethnicity (non-Hispanic = 0, Hispanic = 1)	−0.05	0.03	−0.11	0.01	.134
Cortisol (μg/dl)b	−0.02	0.01	−0.04	0.01	.185

Bold indicates significant effects.

^aLog-transformed variable.

^bArea under the curve with respect to ground.