Table 1 Demographic, smoking and vaping characteristics of experimental groups (n=936)
|
Experimental Groups n (%)^
|
Cigalike
(n=226)
|
Tank system (n=232)
|
Cigarette (n=242)
|
Neutral (n=236)
|
Age (M, SD, range)
|
40 (12)
19-75
|
39 (13)
19-72
|
38 (11)
19-70
|
38 (10)
20-67
|
Gender
|
|
|
|
|
Male
|
71 (31)
|
90 (39)
|
86 (36)
|
81 (34)
|
Female
|
155 (69)
|
142 (61)
|
156 (64)
|
155 (66)
|
Education
|
|
|
|
|
Higher Education or professional
|
102 (45)
|
112 (48)
|
117 (48)
|
116 (49)
|
A levels or equivalent
|
66 (29)
|
64 (28)
|
66 (27)
|
61 (26)
|
GCSE / O level grade A*-C, or equivalent
|
47 (21)
|
52 (22)
|
47 (19)
|
43 (18)
|
Qualifications at level 1 and below
|
3 (1)
|
1 (<1)
|
3 (1)
|
7 (3)
|
Other qualifications: level unknown
|
7 (3)
|
0
|
4 (2)
|
4 (2)
|
No qualifications
|
1 (<1)
|
3 (1)
|
5 (2)
|
5 (2)
|
Smoking and vaping status
|
|
|
|
|
Dual users
|
23 (10)
|
28 (12)
|
20 (8)
|
25 (11)
|
Smokers only
|
67 (30)
|
68 (29)
|
71 (29)
|
72 (31)
|
Vapers only
|
66 (29)
|
68 (29)
|
76 (31)
|
72 (31)
|
Non-users
|
70 (31)
|
68 (29)
|
75 (31)
|
67 (28)
|
^ Unless otherwise stated
A total of 1120 participants completed the study.184 (16%) failed attention checks and were excluded post-randomisation[1], meaning 936 participants were included in the final analysis (see Table 1 for demographic characteristics).
Smoking and vaping urges
There was no clear evidence of an interaction effect between video cue group and smoking and vaping status group for either ANCOVA models: smoking urge (F[9,919]=1.63, p=0.10) and vaping urge (F[9,919]=0.66, p=0.75). Therefore, the interaction was dropped from the model in favour of a single model to estimate main effects with greater precision.
There was no clear evidence of a main effect between the four video cue groups on smoking urge (F[3, 928]=1.33, p=0.26): there was no evidence of a difference in smoking urge between: i. vaping cues (combined) and neutral cue (mean difference [MD]=0.05, 95% CI -0.89 to 0.98, p=0.92), ii. vaping cues (combined) and smoking cue (MD=0.9, 95% CI -0.03 to 1.83, p=0.06), or iii. cigalike and tank system vaping cues (MD=0.1, 95% CI -0.99 to 1.20, p=0.85) (Table 2).
Table 2 Primary and secondary outcomes – adjusted
|
Experimental groups M (95% CIs)
|
Cue type
|
Cigalike
|
Tank system
|
Cigarette
|
Neutral
|
Urge to smoke*
|
25.7 (24.9, 26.5)
|
25.8 (25.0, 26.6)
|
26.6 (25.9, 27.4)
|
25.8 (25.0, 26.6)
|
Urge to vape*
|
25.2 (24.4, 25.9)
|
25.5 (24.7, 26.2)
|
24.1 (23.4, 24.9)
|
23.4 (22.6, 24.1)
|
Desire for a cigarette**
|
28.7 (26.6, 30.7)
|
28.9 (26.9, 30.9)
|
31.2 (29.2, 33.3)
|
28.7 (26.6, 30.7)
|
Desire for an e-cigarette**
|
26.6 (24.8, 28.4)
|
26.3 (24.6, 28.1)
|
25.1 (23.3, 26.8)
|
23.6 (21.9, 25.4)
|
Intention to quit smoking***
|
2.7 (2.4, 2.9)
|
2.9 (2.6, 3.1)
|
2.6 (2.3, 2.8)
|
2.7 (2.5, 3.0)
|
Likelihood remain abstinent ****
|
4.3 (4.2, 4.5)
|
4.2 (4.1, 4.4)
|
4.4 (4.3, 4.6)
|
4.1 (3.9, 4.2)
|
* QSU (Questionnaire of smoking or vaping urges): 10 (minimum) – 70 (maximum)
** Desire for a cigarette / e-cigarette: 0 (not at all) – 100 (most ever)
*** Intentions to quit smoking (current smokers): 1 (least) – 5 (most)
**** Likelihood to remain abstinent from smoking (ex-smokers): 1 (least) – 5 (most)
There was strong evidence of a main effect between the video cue groups on vaping urge (F[3,928]=6.66, p<0.001): urges were higher following exposure to both cigalike (MD=1.8, 95% CI 0.4 to 3.2, p=0.005) and tank system vaping (MD=2.1, 95% CI 0.7 to 3.5, p<0.001) cues compared to the neutral cue (Table 2).
Desire to smoke and vape
There was no clear evidence of a main effect between the four video cue groups on desire to smoke (F[3,928]=1.58, p=0.19) and weak evidence of a difference on desire to vape (F[3,928]=2.43, p=0.06), which was higher following exposure to cigalike (MD=3.0, 95% CI 0.6 to 5.4, p=0.02) and tank system (MD=2.7, 95% CI 0.3 to 5.1, p = 0.03) cues compared to the neutral cue (Table 2).
Intention to quit or remain abstinent
There was no evidence of a main effect of video cue groups on intention to quit smoking (F[3,369]=1.33, p=0.27). There was weak evidence of a main effect of video groups on intention to remain abstinent from smoking (F[3,557]=3.034, p=0.03), which was higher following exposure to the cigarette cue compared to the neutral cue (MD=0.3, 95% CI 0.03 to 0.6, p=0.02) (Table 2).
The results remained unchanged when sensitivity analyses were conducted to remove participants who did not correctly identify the video cue (n=88), or correctly identified the purpose of the study (n=421).
The smoking and vaping urge and desire scores were heavily skewed towards the minimum scores (being 10 and 0 respectively), demonstrating possible floor effects. A comparison amongst video cue groups between those participants at floor or above found that the proportions were similar across groups.