Table 3.

Regression model of age of first use of alcohol, cannabis and tobacco on average daily minutes of MVPA (square root transformed).

Predictor	Levels	Beta estimate	SE	DF	t Value	p = Pr > |t|
Intercept		7.69	0.11	105	70.83	<0.0001
Data collection year	2012 (reference)
	2013	−0.11	0.08	34,000	−1.38	0.17
	2014	−0.16	0.08	34,000	−2.08	0.04
	2015	−0.16	0.08	34,000	−2.02	0.04
	2016	−0.26	0.08	34,000	−3.21	0.00
Sex	Female (reference)
	Male	1.26	0.04	34,000	28.32	<0.0001
Ethnicity	White (reference)
	Black	0.22	0.11	34,000	2.01	0.04
	Asian	−1.11	0.09	34,000	−11.88	<0.0001
	Off-reserve aboriginal	0.34	0.14	34,000	2.48	0.01
	Latin American/Hispanic	−0.13	0.14	34,000	−0.88	0.38
	Other/mixed	−0.10	0.11	34,000	−0.91	0.36
Spending money	Zero (reference)
	$1 to $20	0.70	0.08	34,000	8.28	<0.0001
	$21 to $100	1.22	0.08	34,000	15.73	<0.0001
	More than $100	1.64	0.08	34,000	21.06	<0.0001
	Don't know	0.96	0.10	34,000	10.02	<0.0001
Current drinker	Non-drinker (reference)
	Current drinker	0.53	0.06	34,000	9.22	<0.0001
Current cannabis user	Non-user (reference)
	Current user	0.10	0.07	34,000	1.38	0.17
Current smoker	Non-smoker (reference)
	Current smoker	−0.15	0.08	34,000	−1.91	0.06
Age of first use - alcohol	8	1.05	0.13	34,000	7.81	<0.0001
	9	1.43	0.26	34,000	5.49	<0.0001
	10	0.97	0.18	34,000	5.55	<0.0001
	11	0.78	0.20	34,000	3.81	0.00
	12	0.55	0.12	34,000	4.42	<0.0001
	13	0.57	0.11	34,000	5.41	<0.0001
	14	0.54	0.09	34,000	6.33	<0.0001
	15	0.51	0.08	34,000	6.32	<0.0001
	16	0.45	0.08	34,000	5.67	<0.0001
	17	0.15	0.11	34,000	1.33	0.18
	18	0.15	0.23	34,000	0.64	0.52
	Never used (reference)
Age of first use - cannabis	8	0.79	0.23	34,000	3.36	0.00
	9	−0.96	0.46	34,000	−2.10	0.04
	10	0.28	0.35	34,000	0.82	0.41
	11	0.81	0.33	34,000	2.47	0.01
	12	0.12	0.20	34,000	0.61	0.54
	13	−0.18	0.14	34,000	−1.26	0.21
	14	−0.26	0.11	34,000	−2.46	0.01
	15	−0.20	0.09	34,000	−2.23	0.03
	16	−0.17	0.08	34,000	−2.02	0.04
	17	−0.15	0.10	34,000	−1.54	0.12
	18	−0.46	0.25	34,000	−1.88	0.06
	Never used (reference)
Age of first use - cigarettes	8	0.49	0.19	34,000	2.54	0.01
	9	0.22	0.34	34,000	0.64	0.52
	10	0.19	0.28	34,000	0.67	0.50
	11	0.09	0.28	34,000	0.30	0.76
	12	−0.11	0.18	34,000	−0.65	0.52
	13	0.22	0.15	34,000	1.47	0.14
	14	0.16	0.11	34,000	1.41	0.16
	15	0.22	0.10	34,000	2.18	0.03
	16	0.05	0.09	34,000	0.59	0.56
	17	0.27	0.10	34,000	2.64	0.01
	18	1.00	0.25	34,000	3.97	<0.0001
	Never used (reference)