Table 2.

Mental Health and Substance Use Problems by Sex/Gender and Grade.

Mental Health Scale	Girls						Boys						Total
	Grade 7			Grade 8			Grade 7			Grade 8
	%	SE	n	%	SE	n	%	SE	n	%	SE	n	%	SE	n
GAIN-SS Internalising (3+)a	27.15	2.68	89	33.79	3.04	119	19.48	2.52	64	18.48	2.32	59	24.80	1.49	332
GAIN-SS Externalising (3+)	16.66	2.10	53	24.06	3.54	86	18.51	2.57	60	22.77	2.34	68	20.42	1.67	268
GAIN-SS Substance use problem (1+)b	5.89	1.79	21	9.69	1.49	34	4.52	1.35	15	10.30	1.64	32	7.47	0.70	102
GAIN-SS Concurrent mental health and substance use problem	5.59	1.85	19	8.58	1.52	29	2.33	0.92	9	6.85	1.04	21	5.73	0.82	78
Self-rated mental health fair/poor	9.88	2.07	32	11.50	1.69	42	5.26	1.19	22	6.96	1.27	22	8.35	0.78	118

Note. GAIN-SS, Global Assessment of Individual Needs – Short Screener. Self-reported mental health: poor/ fair vs. good/very good/ excellent). Estimated percentages are adjusted for design characteristics. Unadjusted n’s are also shown. All models controlled for region. To control for multiple comparisons, Bonferroni-adjusted test-wise α = 0.01.

^a Girls > boys, OR = 1.88, SE = 0.29, 99%CI [1.21 to 2.91].

^b Grade 8 > Grade 7, OR = 2.00, SE = 0.49, 99%CI [1.01 to 3.95].