Table 2.

Parameter estimates from hierarchical longitudinal multilevel models for each substance.

	Alc Use	Heavy Drinking	Smoking	Marijuana Use
Model 1
Intercept	−.003	−.005	−.016^**	.005
ICC	.28	.30	.49	.32
Goodness-of-fit
χ²	174005.86	175674.90	157881.63	163577.03

Model 2
Intercept	−1.009^***	−.806^***	−.638^***	−.387^***
Linear Change (Age)	.211^***	.177^***	.139^***	.085^***
Quadratic Change (Age²)	−.008^***	−.007^***	−.006^***	−.003^***
Goodness-of-fit
χ²	163782.95	169011.33	150474.89	159600.69
Comparison Model	1	1	1	1
Δ-2LL (Δdf)	10222.91(4)^***	6663.57(4)^***	7406.74(4)^***	3976.34(4)^***

Model 3
Intercept	−.921^***	−.760^***	−.525^***	−.362^***
Male	−.216^***	−.224^***	−.187^***	−.144^***
Hispanic	.140^***	.244^***	.041	.184^***
African American	.019	.108^***	−.102^***	.036
Asian American	−.277^***	−.109^*	−.112^*	.050
Linear Change (Age)	.220^***	.189^***	.164^***	.079^***
Male* Age	.081^***	.097^***	.052^***	.061^***
Hispanic* Age	−.089^***	−.114^***	−.106^***	−.061^***
AA* Age	−.125^***	−.145^***	−.115^***	−.039^***
Asian* Age	−.045^***	−.083^***	−.080^***	−.063^***
Quadratic Change (Age²)	−.009^***	−.008^***	−.007^***	−.003^***
Male* Age²	−.003^***	−.003^***	−.002^***	−.002^***
Hispanic* Age²	.004^***	.005^***	.005^***	.002^***
AA* Age²	.006^***	.007^***	.006^***	.002^***
Asian* Age²	.003^***	.004^***	.004^***	.003^***
Goodness-of-fit
χ²	160591.98	165618.98	147882.42	158937.83
Comparison model	2	2	2	2
Δ-2LL (Δdf)	3190.97(12)^***	3392.35(12)^***	2592.47(12)^***	662.86(12)^***
Pseudo R²
R_ε² (within-person)	30.0%	25.4%	31.8%	17.0%
R₀² (level 2 initial status)	7.8%	6.4%	13.0%	0.2%
R₁² (level 2 age)	9.9%	7.4%	4.1%	4.9%

Note. ICC = Intraclass correlation.

p < .05,

^**

p < .01,

^***

p < .001