Table 1. Sample characteristics at baseline.

			Overall					6th Graders (n=3035)						7th Graders (n=3062)
Variable	N	%	Mean	SD	Min	Max	N	%	Mean	SD	Min	Max	N	%	Mean	SD	Min	Max	P-value
AGE_YR1			11.6	0.7	9	16			11.1	0.5	9	16			12.1	0.5	10	15	<.0001
Gender																			0.2388
Male	3044	49.9					1538	50.7					1506	49.2
Female	3052	50.1					14.96	49.3					1556	50.8
Race																			<.0001
Hispanic/Latino(a)	3261	53.5					1615	53.3					1646	53.8
Non-Hispanic   White	953	15.6					434	14.3					519	17.0
Non-Hispanic Black	192	3.2					96	3.2					96	3.1
Non-Hispanic   Asian	1010	16.6					498	16.4					512	16.7
Other ethnicity	677	11.1					390	12.9					287	9.4
Alcohol
Drinker in past 30   days	292	5.3					108	3.9					184	6.6					<.0001
Perceived norms			10.0	18.3	0	100			5.4	13.4	0	100			14.2	20.9	0	100	<.0001
Peer use			0.3	0.8	0	3			0.2	0.6	0	3			0.5	0.9	0	3	<.0001
Offers			0.3	1.0	0	6			0.2	0.8	0	6			0.5	1.2	0	6	<.0001
Marijuana
User in past 30   days	154	2.8					46	1.7					108	3.9					<.0001
Perceived norms			9.0	17.8	0	100			3.9	11.6	0	100			13.6	21.0	0	100	<.0001
Peer use			0.3	0.8	0	3			0.2	0.6	0	3			0.5	0.9	0	3	<.0001
Offers			0.3	1.0	0	6			0.1	0.7	0	6			0.4	1.2	0	6	<.0001
Cigarettes
Smoker in past 30   days	109	2.0					44	1.6					65	2.3
Perceived norms			7.0	14.5	0	100			3.7	10.9	0	100			10.0	16.6	0	100	<.0001
Peer use			0.3	0.7	0	3			0.2	0.5	0	3			0.4	0.8	0	3	<.0001
Offers			0.2	0.8	0	6			0.1	0.7	0	6			0.3	1.0	0	6	<.0001