Table 2.

Results of secondary analyses

		Group		Nonverbal IQ		Group x Nonverbal IQ
	df	F	p	F	p	F	p
Dependent variable
Gestational age (category)	555	4.12	0.04	1.67	0.20	2.43	0.12
Birthweight (square-root)	561	10.37	0.00	14.24	0.00	1.55	0.21
APGAR score (1 min)	551	0.55	0.46	3.61	0.06	0.1	0.75
APGAR score (5 min)	553	0.34	0.56	3.64	0.06	0.1	0.75
First words by 24 months	465	17.41	<.0001	31.81	<.0001	2.48	0.12
First phrase by 36 months	507	1.81	0.18	86.36	<.0001	0.42	0.52

Note: Some missing data; see Table 1.