Table 1.

Parental monitoring at age 11 and initiation of cannabis use up to age 17, unadjusted and adjusted models. Data are from 638 children sampled from 1983 to 1985 newborn discharge lists from two hospitals in southeast Michigan with complete information on all variables.

Variable	n	Estimated percentage of cannabis initiation 11–17 years	ERR	[95% CI]	p	AERR	[95% CI]	p
Parental monitoring Birth weight	638	34.8%	0.94	[0.93, 0.97]	<.001	0.96	[0.93, 0.98]	<.001
Low	361	34.1%	0.95	[0.77, 1.18]	.661	0.86	[0.70, 1.05]	.132
Normal	277	35.7%	ref.			ref.
Community
Urban	331	34.4%	0.98	[0.79, 1.21]	.845	1.01	[0.75, 1.37]	.925
Suburban	307	35.2%	ref.			ref.
Race
Black	291	32.3%	0.88	[0.71, 1.09]	.229	0.64	[0.47, 0.86]	.003
White	347	36.9%	ref.			ref.
Sex
Male	296	41.6%	1.44	[1.16, 1.78]	.001	1.24	[0.99, 1.54]	.056
Female	342	29.0%	ref.			ref.
Externalizing at age 11	638	34.8%	1.02	[1.01, 1.03]	.001	1.01	[1.00, 1.02]	.160
Smoked tobacco by age 11
Yes	63	63.5%	2.01	[1.61,2.51]	<.001	1.31	[1.02, 1.69]	.037
No	575	31.6%	ref.			ref.
Drank alcohol by age 11
Yes	63	54.0%	1.65	[1.28,2.13]	.001	0.96	[0.71, 1.30]	.784
No	575	32.7%	ref.			ref.
Had a friend who smoked tobacco at age 11
Yes	180	52.8%	1.90	[1.55,2.33]	<.001	1.59	[1.28, 1.98]	<.001
No	458	27.7%	ref.			ref.
Had a friend who drank alcohol at age 11
Yes	124	50.0%	1.61	[1.29,2.00]	<.001	1.25	[0.99, 1.57]	.061
No	514	31.1%	ref.			ref.
Maternal education
<High school	99	37.4%	ref.			ref.
High school	169	37.3%	1.00	[0.72, 1.38]	.988	1.18	[0.86, 1.61]	.309
Some college	246	33.7%	0.90	[0.66, 1.23]	.517	1.07	[0.79, 1.44]	.673
College	124	31.4%	0.84	[0.58, 1.21]	.353	1.38	[0.94,2.01]	.100
Maternal marital status
Single	208	42.3%	1.36	[1.10, 1.68]	.005	1.60	[1.25,2.05]	<.001
Married	430	31.2%	ref.			ref.
Maternal tobacco smoking at baseline
Smoker	233	45.9%	1.62	[1.31, 1.99]	<.001	1.52	[1.23, 1.88]	<.001
Nonsmoker	405	28.4%	ref.			ref.

Notes: ERR = estimated relative risk; CI = confidence interval; AERR = adjusted ERR; ref. = reference.