Logistic regression of 3-month outcome
| 95% CI for OR | ||||
| P values | OR | Lower | Upper | |
| AC (vs Quit.ie) | 0.01 | 2.26 | 1.22 | 4.21 |
| Female (vs male) | 0.94 | 1.03 | 0.55 | 1.92 |
| Higher (vs lower) education | 0.002 | 3.62 | 1.58 | 8.28 |
| Age | 0.89 | 1.00 | 0.97 | 1.04 |
| Prior use of e-cigarette (vs non-use) | 0.93 | 0.97 | 0.52 | 1.82 |
| Baseline CO reading | 0.005 | 0.96 | 0.92 | 0.99 |
| Time to first cigarette (vs ≤5 min) | 0.42 | |||
| 6–30 min | 0.19 | 0.61 | 0.29 | 1.28 |
| >31 min | 0.61 | 0.80 | 0.35 | 1.86 |
| Readiness to quit score | 0.95 | 1.00 | 0.91 | 1.09 |
| Previous attempts to quit (vs none) | 0.10 | |||
| 1–3 | 0.51 | 2.11 | 0.23 | 19.01 |
| 4–9 | 0.33 | 2.90 | 0.32 | 26.33 |
| 10+ | 0.11 | 6.72 | 0.66 | 68.22 |
| Constant | 0.16 | 0.07 | ||
AC, Allen Carr’s Easyway to Stop Smoking; CO, carbon monoxide.