“The Real Cost” Smokeless campaign: changes in beliefs about smokeless tobacco among rural boys, a longitudinal randomized controlled field trial

Table 3 Multivariate Difference in Difference

Belief	DID All Waves (n = 8869)	DID All Waves (Ages 11–13) (n = 4442)	DID All Waves (Ages 14–16) (n = 4411)	DID Baseline to Follow-up 2 (n = 5753)
If I use smokeless tobacco, I will
Damage my body	2.7	0.5	4.8*	4.0*
Be controlled by SLT	3.8	0.8	6.8*	4.4
Develop cancer of the lip, mouth, tongue, or throat	1.0	0.7	1.1	2.1
Be unable to stop when I want to	7.1**	4.3	10.1**	8.1**
Lose my teeth	1.9	0.9	3.1	2.8
Shorten my life	2.2	−0.2	4.5	2.9
Miss out on things I enjoy doing	1.5	0.9	2.3	2.2
Develop gum disease	3.1	0.7	5.6*	3.8
Develop red or white patches in the mouth	0.6	−2.5	3.5	1.5
Consume harmful chemicals	0.9	0.7	1.1	1.4
Cause immediate damage to my body	−4.2	−5.2	−3.2	−2.6

^aAll variables are coded: 1 = Strongly Agree/Agree; 0 = Neutral/Disagree/Strongly Disagree
^bCells present adjusted percentage point changes (Δ Treatment – Δ Control)
^cBoldface indicates statistical significance (* p ≤ 0.05, ** p ≤ 0.01, *** p ≤ 0.001)
^dMultivariate models controlled for the youth’s age and race, parent’s education, household income, work status, and marital status, biological parent vs. not, youth’s use of TV, social media, streaming services, and video games, youth awareness of the truth campaign and a fake media campaign (for an additional control), youth sensation seeking, school performance and church attendance, youth willingness to do things they don’t want to do in order to keep friends or please friends, use of SLT or cigarettes by others in the household, rules about media use and watching R-rated movies, and whether the youth completed the survey in person or online

ISSN: 1471-2458