Table 4.
Wave 1 to Wave 2 transition subgroup comparisons: progression towards discontinuing smoking among daily and non-daily smokers and relapse among ex-smokers based on baseline frequency of smoking and vaping.
| Wave 1 to Wave 2 Transitions | Transition Code * | Comparisons between Wave 1 Subgroups | OR | 95% CI | |
|---|---|---|---|---|---|
| No change in smoking frequency (daily) | A (i) | 1 | Exclusive daily smokers | Reference | |
| 3 vs. 1 | Dual-daily users | 0.72 | 0.49–1.05 | ||
| 4 vs. 1 | Predominant smokers | 0.91 | 0.67–1.24 | ||
| No change in smoking frequency (non-daily) | A (ii) | 2 | Exclusive non-daily smokers | Reference | |
| 5 vs. 2 | Predominant vapers | 0.99 | 0.51–1.90 | ||
| 6 vs. 2 | Concurrent non-daily users | 2.60 | 1.45–4.67 | ||
| Decreased smoking from daily to non-daily | B | 1 | Exclusive daily smokers | Reference | |
| 3 vs. 1 | Dual-daily users | 2.41 | 1.42–4.10 | ||
| 4 vs. 1 | Predominant smokers | 1.90 | 1.23–2.95 | ||
| Increased smoking from non-daily to daily | C | 2 | Exclusive non-daily smokers | Reference | |
| 5 vs. 2 | Predominant vapers | 1.12 | 0.58–2.15 | ||
| 6 vs. 2 | Concurrent non-daily users | 0.54 | 0.28–1.04 | ||
| Discontinued smoking | D (i) | 1 + 3 + 4 | Daily smokers | Reference | |
| 2 + 5 + 6 vs. 1 + 3 + 4 | Non-daily smokers | 2.48 | 1.80–3.43 | ||
| D (ii) | 1 | Exclusive daily smokers | Reference | ||
| 3 vs. 1 | Dual-daily users | 0.87 | 0.53–1.41 | ||
| 4 vs. 1 | Predominant smokers | 0.75 | 0.50–1.12 | ||
| D (iii) | 2 | Exclusive non-daily smokers | Reference | ||
| 5 vs. 2 | Predominant vapers | 0.89 | 0.43–1.83 | ||
| 6 vs. 2 | Concurrent non-daily users | 0.55 | 0.29–1.06 | ||
| D (iv) | 3 | Dual-daily users | Reference | ||
| 4 vs. 3 | Predominant smokers | 0.83 | 0.48–1.45 | ||
| 5 vs. 3 | Predominant vapers | 2.40 | 1.07–5.35 | ||
| 6 vs. 3 | Concurrent non-daily users | 1.86 | 0.92–3.75 | ||
| Relapsed back to smoking | E | 7 | Ex-smokers who vape | Reference | |
| 8 vs. 7 | Ex-smokers who don’t vape | 1.04 | 0.36–3.03 | ||
| Initiated Vaping | F | 1 | Exclusive daily smokers | Reference | |
| 2 vs. 1 | Exclusive non-daily smokers | 1.52 | 1.02–2.25 | ||
| Discontinued smoking and switched to vaping | G (i) | 1 + 3 + 4 | Daily smokers | Reference | |
| 2 + 5 + 6 vs. 1 + 3 + 4 | Non-daily smokers | 2.21 | 1.25–3.91 | ||
| G (ii) | 1 | Exclusive daily smokers | Reference | ||
| 3 vs. 1 | Dual-daily users | 3.55 | 1.90–6.64 | ||
| 4 vs. 1 | Predominant smokers | 1.88 | 1.09–3.23 | ||
| G (iii) | 2 | Exclusive non-daily smokers | Reference | ||
| 5 vs. 2 | Predominant vapers | 4.99 | 1.82–13.72 | ||
| 6 vs. 2 | Concurrent non-daily users | 1.81 | 0.61–5.35 | ||
| G (iv) | 3 | Dual-daily users | Reference | ||
| 4 vs. 3 | Predominant smokers | 0.52 | 0.27–1.01 | ||
| 5 vs. 3 | Predominant vapers | 2.25 | 0.89–5.70 | ||
| 6 vs. 3 | Concurrent non-daily users | 1.09 | 0.44–2.72 | ||
Data are weighted and adjusted with covariates. The “group comparison” numbering system refers to Table 1. * Transition codes refer to the group comparisons as described for the second analyses in the Statistical Analyses Section 2.3. Control groups were exclusive smokers (compared to concurrent users). Among concurrent users, dual-daily users were used as the control group (the group with the most frequent smoking and vaping); vs: versus. Bold odds ratios indicate significance. OR: Odds ratio; CI: Confidence interval.