Table 3.

Unconditional Linear and Quadratic Models of Growth

	Linear		Linear and quadratic
Effect	Coefficient	SE	Coefficient	SE
Fixed effects
Intercept	2.78***	.02	2.73***	.036
Linear slope	.09***	.005	.13***	.018
Quadratic slope			−.005*	.002
Random effects
Intercept	.274***	.025	.192***	.03
Linear slope	.01***	.001	.016	.01
Quadratic slope			−.00	.00
Level-1 error	.158***	.003	.155***	.003
Model fit
−2 log likelihood	11,810.70		11,757.80
AIC	11,822.70		11,777.80
BIC	11,853.90		11,839.90

Note. AIC = Akaike information criterion. BIC = Bayesian information criterion.

^*p < .05.

^***p < .001.