Table 3.

Study 1: Nested Model Comparisons of Autoregressive Latent Trajectory Model Successively Adding Each Direction of Effect Between Language Ability and Behavior Problems (Q2: What Is the Direction of Effect Between Language Ability and Behavior Problems?)

	Inattentive-Hyperactive				Externalizing
	Teacher		Mother		Teacher		Mother
Step	Δχ2	p	Δχ2	p	Δχ2	p	Δχ2	p
Testing language ability → Behavior problems
1. Adding Lang → BP	10.92	.001	37.89	<.001	7.87	.005	15.96	<.001
2. Adding BP → Lang	4.52	.034	0.18	.667	0.53	.465	2.11	.147
Testing behavior problems → Language ability
1. Adding BP → Lang	1.26	.096	1.10	.723	0.14	.710	1.24	.358
2. Adding Lang → BP	12.96	<.001	37.44	<.001	9.36	.002	17.58	<.001

Note. All chi-square tests had 1 df. Parameters where p< .05 in bold, p< .10 in italics. Teacher and mother refer to teacher and mother-reported behavior problems, respectively. BP = behavior problems; Lang = language ability.