Table 4

Multilevel models predicting perceived message effectiveness (PME) for other message features

	k	Overall		Vaped in past 30 days		Susceptible to vaping		Non-susceptible to vaping
		N=1501		n=464		n=649		n=388
		b	95% CI	b	95% CI	b	95% CI	b	95% CI
*Other message features*
Text features
Includes ‘fact’ or ‘factoid’	48	0.008	−0.04 to 0.05	−0.03	−0.11 to 0.05	0.04	−0.03 to 0.12	0.01	−0.08 to 0.09
Uses a hashtag (#)	27	−0.20 **	−0.25 to −0.14	−0.17**	−0.27 to −0.07	−0.26**	−0.36 to −0.17	−0.11	−0.22 to 0.01
Poses a question	23	0.09*	0.03 to 0.15	0.08	−0.03 to 0.19	0.09	−0.01 to 0.19	0.1	−0.02 to 0.22
Uses a statistic	22	−0.38**	−0.44 to −0.32	−0.31**	−0.42 to −0.20	−0.39**	−0.50 to −0.29	−0.43**	−0.56 to −0.31
Cites specific study	4	0.46**	0.32 to 0.60	0.33*	0.09 to 0.57	0.53**	0.32 to 0.75	0.5*	0.18 to 0.81
Message perspective
Uses word ‘you’	79	0.2**	0.16 to 0.24	0.18**	0.12 to 0.25	0.25**	0.18 to 0.31	0.14**	0.07 to 0.21
Uses words ‘I’ or ‘we’	16	−0.33**	−0.41 to −0.26	−0.23**	−0.35 to −0.10	−0.43**	−0.55 to −0.31	−0.31**	−0.46 to −0.17
Uses word ‘teen’	10	−0.21**	−0.31 to −0.12	−0.26**	−0.41 to −0.12	−0.2*	−0.36 to −0.05	−0.11	−0.31 to 0.09
Other
Source included	122	0.09**	0.05 to 0.13	0.02	−0.04 to 0.09	0.14**	0.08 to 0.20	0.07	−0.003 to 0.14
Bright/vivid colours	89	−0.12**	−0.16 to −0.08	−0.14**	−0.21 to −0.08	−0.12**	−0.18 to −0.06	−0.09*	−0.17 to −0.02
Internet meme	6	−0.34**	−0.46 to −0.22	−0.16	−0.36 to 0.04	−0.38**	−0.57 to −0.20	−0.49**	−0.71 to −0.26

Outcome is composite score for three-item PME scale: 1=not at all, 2=very little, 3=somewhat, 4=quite a bit, 5=very much (ɑ=0.93); *p<0.05, **p<0.001. Models adjusted for gender, age, race, ethnicity, maternal education, cigarette use and use of one or more other tobacco products.