Table 3

Comprehension and credibility of warnings, and warning persuasiveness among adolescents (11–16 years), Youth Tobacco Policy Survey (YTPS) Wave 5 (2008) and Wave 6 (2011)

	Total sample				Never smokers				Experimental smokers				Regular smokers
	Percentages		Test of difference by year*		Percentages		Test of difference by year†		Percentages		Test of diff by year†		Percentages		Test of diff by year†
	2008	2011	AOR	p Value	2008	2011	AOR	p Value	2008	2011	AOR	p Value	2008	2011	AOR	p Value
Comprehension and credibility
Easy to understand	91	90	0.825	0.154	92	89	0.695	0.024	91	93	1.041	0.905	88	91	1.455	0.415
Believable	87	90	1.207	0.142	91	92	1.126	0.489	84	93	2.523	0.002	66	63	0.78	0.377
Truthful in respect to the health risks associated with smoking	86	90	1.430	0.005	90	92	1.24	0.179	85	94	2.969	0.001	67	73	1.115	0.717
Persuasiveness
Puts me off smoking	81	85	1.380	0.014	91	93	1.354	0.084	79	86	1.647	0.041	13	14	0.897	0.782
Makes me less likely to smoke	81	87	1.527	0.001	91	95	1.728	0.004	78	86	1.808	0.015	21	20	0.782	0.471
Base: all respondents (number varies due to missing values)	1357–1372	1321–1348			914–927	975–1001			305–306	228–229			131–135	113–115

*p Values are based on logistic regressions, testing differences 2011 vs 2008 after controlling for peer and family smoking, age, gender, social grade and smoking status.
†p Values are based on logistic regressions, testing differences 2011 vs 2008 after controlling for peer and family smoking, age, gender and social grade.
AOR, adjusted ORs.