Table 4. Associations between use of smoking cessation aids and abstinence.
Unadjusted abstinence (%) |
Model 1 OR [95% CI] |
Model 2 OR [95% CI] |
Model 3 OR [95% CI] |
|
---|---|---|---|---|
No aid | 16.8 | - | 0.75 [0.69-0.83]*** | - |
Prescription NRT1 | 14.1 | 0.88 [0.76-1.02] | 1.28 [1.08-1.52]** | 1.34 [1.12-1.59]** |
Age 16-44 years | 11.9 | 0.69 [0.55-0.87]*** | 1.05 [0.821.36] | 1.09 [0.85-1.42] |
Age ≥45 years | 16.5 | 1.04 [0.85-1.28] | 1.50 [1.19-1.88]** | 1.58 [1.25-2.00]*** |
NRT bought over the counter | 11.6 | 0.68 [0.61-0.75]*** | 0.88 [0.79-0.99]* | 0.98 [0.87-1.09] |
Varenicline | 20.4 | 1.31 [1.11-1.54]** | 1.67 [1.38-2.01]*** | 1.82 [1.51-2.21]*** |
Bupropion | 11.7 | 0.74 [0.52-1.05] | 1.23 [0.83-1.81] | 1.27 [0.86-1.89] |
E-cigarettes2 | 21.2 | 1.49 [1.34-1.67]*** | 1.86 [1.62-2.13]*** | 1.95 [1.69-2.24]*** |
Men | 24.3 | 1.76 [1.51-2.04]*** | 2.15 [1.78-2.60]*** | 2.26 [1.87-2.74]*** |
Women | 18.1 | 1.25 [1.06-1.47]** | 1.58 [1.29-1.94]*** | 1.66 [1.35-2.04]*** |
Face-to-face behavioural support | 15.4 | 1.02 [0.84-1.24] | 1.24 [1.00-1.55] | 1.20 [0.95-1.50] |
Telephone support3,4 | 11.1 | 0.66 [0.39-1.12] | 0.83 [0.47-1.47] | 0.75 [0.42-1.35] |
Low cigarette addiction | 10.3 | 0.57 [0.30-1.07] | 0.60 [0.29-1.21] | 0.51 [0.25-1.06] |
High cigarette addiction | 12.3 | 1.48 [0.58-3.77] | 1.62 [0.63-4.14] | 1.67 [0.64-4.37] |
Social grade ABC1 | 17.7 | 1.01 [0.51-2.00] | 1.52 [0.70-3.32] | 1.57 [0.70-3.49] |
Social grade C2DE | 7.0 | 0.44 [0.19-1.00] | 1.07 [0.89-1.28] | 0.40 [0.16-0.99]* |
Written self-help materials3 | 16.8 | 0.91 [0.66-1.26] | 0.92 [0.64-1.32] | 0.91 [0.63-1.32] |
Low cigarette addiction | 22.5 | 1.05 [0.74-1.47] | 1.06 [0.71-1.57] | 1.07 [0.71-1.60] |
High cigarette addiction | 3.3 | 0.15 [0.02-1.11] | 0.17 [0.02-1.22] | 0.16 [0.02-1.15] |
Websites3,4,5 | 18.6 | 1.07 [0.73-1.57] | 1.19 [0.78-1.83] | 1.25 [0.81-1.92] |
Age 16-44 years | 18.5 | 1.23 [0.80-1.88] | 1.42 [0.88-2.28] | 1.54 [0.95-2.49] |
Age ≥45 years | 19.1 | 0.74 [0.31-1.76] | 0.62 [0.24-1.62] | 0.56 [0.21-1.49] |
Low cigarette addiction | 21.6 | 0.94 [0.62-1.43] | 1.08 [0.66-1.77] | 1.15 [0.70-1.87] |
High cigarette addiction | 9.8 | 1.97 [0.76-5.09] | 2.15 [0.82-5.60] | 2.51 [0.93-6.75] |
Social grade ABC1 | 20.0 | 0.73 [0.40-1.38] | 0.73 [0.40-1.35] | 0.74 [0.40-1.38] |
Social grade C2DE | 17.0 | 1.46 [0.86-2.49] | 2.14 [1.18-3.87]* | 2.20 [1.22-3.98]** |
Hypnotherapy6 | 17.3 | 0.92 [0.58-1.44] | 0.81 [0.48-1.35] | 0.84 [0.50-1.40] |
Low cigarette addiction | 24.3 | 1.06 [0.66-1.72] | 0.85 [0.48-1.51] | 0.92 [0.52-1.63] |
High cigarette addiction | 2.0 | 0.34 [0.05-2.49] | 0.30 [0.04-2.22] | 0.31 [0.04-2.31] |
OR = odds ratio; CI = confidence interval; NRT = nicotine replacement therapy. Low cigarette addiction = score of 0-2 on strength of urges to stop scale; high cigarette addiction = score of 3-5 on strength of urges to stop scale.
Model 1 = multivariable model including all smoking cessation aid variables, but no covariates.
Model 2 = multivariable model including all covariates (age, sex, social grade, strength of urges to smoke, time since the quit attempt started, number of prior quit attempts in the past year, whether the quit attempt was planned, whether the respondent quit abruptly versus gradually, and month and year of the survey), but no other smoking cessation aid variables.
Model 3 = fully adjusted multivariable model including all covariates and all smoking cessation aid variables.
Each OR and 95% CI is for using the smoking cessation aid in question relative to not using that smoking cessation aid.
*p < 0.05; **p < 0.01; ***p < 0.001.
Interactions showed effectiveness differed significantly by age (Table 4).
Bayes factor indicated that the data provided moderate evidence of differing effectiveness by sex (Supplementary Table 1) despite the interaction not reaching statistical significance (Table 4).
Effectiveness differed significantly by level of cigarette addiction (Table 4).
Effectiveness differed significantly by social grade (Table 4).
Bayes factor indicated that the data provided strong evidence of differing effectiveness by sex (Supplementary Table 1) despite the interaction not reaching statistical significance (Table 4).
Bayes factor indicated that the data provided moderate evidence of differing effectiveness by level of cigarette addiction (Supplementary Table 1) despite the interaction not reaching statistical significance (Table 4).