Table 2.

Internal consistency of knowledge, attitude and harm scales

Scale	alpha	p	Component factors	% of variance
Knowledge scale	.859	< 0.001
Attitudes towards alcohol	.387	< 0.001	Knowledge and communication	30.6
			Harm	23.5
Alcohol harm scale	.949	< 0.001
Attitudes towards tobacco	.445	< 0.001	Harm	32.4
			Knowledge and communication	21.1
Tobacco harm scale	.802	< 0.001
Attitudes towards cannabis	.548	< 0.001
Cannabis harm scale	.891	< 0.001
Attitudes towards other drugs	.284	< 0.001	Knowledge and communication	32.7
			Harm	25.2
Other drugs harm scale	.609	< 0.001