Table 4.

Prevalence of regular substance use across the 2003, 2009 and 2015 YPICHS samples.

	Year (n)	Prevalence (%)	OR [95% CI]	p	aOR [95% CI]	p
Smoked cigarettes (past 12 months)	2003 (225)	186 (82.7)	1.00 [ref]
	2009 (317)	252 (79.5)	0.81 [0.52, 1.26]	.36
	2015 (226)	186 (82.3)	0.98 [0.60, 1.59]	.92
Smoke cigarettes (currently)	2003 (217)	127 (58.0)	1.00 [ref]
	2009 (317)	67 (21.1)	0.19[0.13, 0.28]	< .001	0.19[0.12, 0.28]	< .001
Drunk	2003 (217)	72 (33.2)	1.00 [ref]
	2009 (315)	189 (60.0)	3.02[2.10, 4.34]	< .001	2.68[1.83, 3.92]	< .001
	2015 (225)	79 (35.1)	1.09 [0.74, 1.62]	.67
Cannabis	2003 (224)	158 (70.5)	1.00 [ref]
	2009 (299)	190 (63.5)	0.73 [0.50, 1.06]	.09
	2015 (224)	171 (76.3)	1.35 [0.88, 2.05]	.17
Heroin	2003 (223)	22 (9.9)	1.00 [ref]
	2009 (317)	4 (1.3)	0.12[0.04, 0.34]	< .001	0.14[0.05, 0.42]	< .001
	2015 (225)	5 (2.2)	0.21[0.08, 0.56]	< .01	0.18[0.07, 0.51]	< .01
Cocaine	2003 (224)	14 (6.3)	1.00 [ref]
	2009 (313)	13 (4.2)	0.64 [0.30, 1.40]	.27
	2015 (225)	13 (5.8)	0.91 [0.42, 1.99]	.82
Amphetamines	2003 (223)	47 (21.1)	1.00 [ref]
	2009 (312)	32 (10.3)	0.43[0.26, 0.70]	< .01	0.41[0.24, 0.69]	< .01
	2015 (225)	4 (1.8)	0.07[0.02, 0.19]	< .001	0.05[0.02, 0.16]	< .001
Methamphetamines	2003	–
	2009 (314)	16 (5.1)	1.00 [ref]
	2015 (225)	67 (29.8)	7.90[4.43, 14.08]	< .001	6.74[2.67, 12.35]	< .001
Steroids	2003 (224)	2 (0.9)	1.00 [ref]
	2009(316)	1 (0.3)	0.35 [0.03, 3.91]	.40
	2015 (225)	3 (1.3)	1.50 [0.25, 9.06]	.66

Note: YPICHS = Young People in Custody Health Survey; OR = odds ratio; aOR = adjusted odds ratio; CI = confidence interval. Regular use: used at least once per week (within past 12 months). Multivariate analyses include the following additional covariates: Indigenous status, language spoken at home, school attendance prior to incarceration, parental incarceration, previous incarceration and offence type.

Bolded = p significant at the < .05 level.