Table 3.

Bivariate independent contrast analysis of sleep (TST is total sleep time) and relative neonatal brain mass, relative gestation length, and relative neonatal body mass. Neonatal brain mass was corrected for allometry using neonatal body mass.

Predictor	Dependent variable	Linear regression
Relative neonatal brain mass	REM	t24=0.01 R2< 0.01 P=0.920
	NREM	t24=0.67 R2=0.02 P=0.508
	TST	t24=0.28 R2=0.01 P=0.782
Relative gestation length	REM	t56=−4.02 R2=0.22 P<0.001
	NREM	t56=−3.20 R2=0.15 P=0.002
	TST	t56=−3.92 R2=0.22 P<0.001
Relative neonatal body mass	REM	t52=−3.58 R2=0.20 P=0.001
	NREM	t52=−1.67 R2=0.05 P=0.102
	TST	t52=−2.78 R2=0.13 P=0.008