Table 1.
Abstinence during a 4-week follow-up after immediate or gradual nicotine reduction or smoking normal nicotine cigarettes (control).
| Control group (n = 249) | Gradual reduction group (n = 498) | Immediate reduction group (n = 503) | |
|---|---|---|---|
| 7-day point-prevalence abstinence, n (%) | 15 (6.0) | 50 (10.0) | 46 (9.2) |
| Odds ratio (95% CI) | Reference | 1.7 (0.96, 3.2) | 1.6 (0.9, 2.9) |
| – | Reference | 0.9 (0.6, 1.4) | |
| Cigarette-free days, mean (SD) a | 3.2 (7.7) | 4.6 (9.3) | 4.7 (9.3) |
| Rate Ratio b (95% CI) | Reference | 1.4 (1.04, 1.9) | 1.5 (1.1, 2.0) |
| – | Reference | 1.0 (0.8, 1.3) |
Note:
a
Median days of abstinence = 0 for all three groups.
b
Rate ratio, and not mean difference, is reported because data were analyzed using a quasi-Poisson model. 7-day point-prevalence abstinence was CO-verified. Days of abstinence were self-reported. Significant (p < .05) findings are bolded. Missing data were treated as smoking. See Table S2 for findings when missing data are handled with multiple imputation.