Table 3.
Bivariate logistic regression models for smoking rates at 12 weeks*
| Variable | Odds ratio (smoking) | 95% confidence intervals for the odds ratio | p-value |
|---|---|---|---|
| Age† | 0.976 | 0.967 to 0.986 | <0.0001 |
| Age started smoking† | 0.976 | 0.960 to 0.993 | 0.0070 |
| Marital status | <0.0001 | ||
| Not married | 1.000 | ||
| Married | 0.623 | 0.494 to 0.784 | |
| Fagerström score† | 1.197 | 1.134 to 1.263 | <0.0001 |
| Prior quit attempt | 0.0011 | ||
| No | 1.000 | ||
| Yes | 1.853 | 1.279 to 2.684 | |
| Quit before for at least 1 day | 0.0083 | ||
| No | 1.000 | ||
| Yes | 0.601 | 0.412 to 0.877 | |
| 40 or more cigarettes per day at study entry | 0.0396 | ||
| No | 1.000 | ||
| Yes | 1.498 | 1.019 to 2.202 | |
| Major depression | 0.0408 | ||
| No | 1.000 | ||
| Yes | 1.357 | 1.013 to 1.819 | |
| Treatment | <0.0001 | ||
| Nicotine inhaler | 1.000 | ||
| Bupropion | 0.489 | 0.361 to 0.661 | |
| Combination treatment | 0.323 | 0.241 to 0.433 | |
| Gender | 0.0681 | ||
| Female | 1.000 | ||
| Male | 0.812 | 0.649 to 1.016 | |
| Education beyond high school | 0.8938 | ||
| No | 1.000 | ||
| Yes | 0.984 | 0.771 to 1.255 | |
| BMI† | 0.990 | 0.973 to 1.008 | 0.2858 |
| Tried prior nicotine | 0.8026 | ||
| No | 1.000 | ||
| Yes | 0.972 | 0.778 to 1.214 | |
| Number of years smoked | 0.4885 | ||
| Less than 5 Years | 1.047 | 0.600 to 1.827 | |
| At least 5 years but less than 10 years | 1.000 | ||
| 10 years or more | 0.825 | 0.581 to 1.172 | |
| Race | 0.0072 | ||
| White | 1.000 | ||
| Minority | 1.781 | 1.169 to 2.714 |
†Age, age started smoking, BMI, and Fagerstrom score were treated as continuous variables. For these variables the odds ratio presented is for a one-unit increase (i.e., per 1-year increase in age). All other characteristics were treated as categorical variables. For these characteristics an odds ratio of 1.000 is used to indicate the reference group. Odds ratios >1.000 indicate an increased likelihood of smoking at 12 weeks