Table 3.
Influence of variables in NRT trials on cessation rates with placebo. Intervention is as described in each review, and details of the reviews is in Table 1.
| Variable | Numbers of patients | Percent abstinent with | Relative benefit (95% CI) | NNT (95% CI) | |
|---|---|---|---|---|---|
| NRT | Placebo | ||||
| All trials six months or longer | 43,108 | 17 | 10 | 1.6 (1.5 to 1.7) | 16 (14 to 17) |
| Duration of follow up | |||||
| Six months | 4,480 | 20 | 9 | 1.9 (1.6 to 2.2) | 9.4 (7.9 to 12) |
| Twelve months | 24,520 | 15 | 10 | 1.5 (1.4 to 1.6) | 21 (18 to 25) |
| Trial setting | |||||
| Community volunteers | 18,823 | 20 | 14 | 1.5 (1.4 to 1.7) | 17 (14 to 20) |
| Smoking clinic | 1,283 | 30 | 19 | 1.6 (1.3 to 1.9) | 9 (7 to 17) |
| Primary care | 11,427 | 11 | 7 | 1.5 (1.3 to 1.7) | 25 (20 to 34) |
| Hospital recruitment | 3,236 | 14 | 10 | 1.3 (1.04 to 1.6) | 25 (16 to 62) |
| Level and type of support | |||||
| Low level of support | 12,348 | 13 | 8 | 1.6 (1.4 to 1.7) | 20 (16 to 25) |
| High level support for individual | 16,907 | 15 | 10 | 1.5 (1.4 to 1.6) | 21 (17 to 26) |
| High level support for group | 7,140 | 27 | 18 | 1.6 (1.4 to 1.7) | 11 (9 to 14) |
| Type of NRT | |||||
| Gum | 19,120 | 18 | 11 | 1.4 (1.3 to 1.5) | 15 (13 to 17) |
| Patch | 18,175 | 16 | 10 | 1.7 (1.5 to 1.8) | 17 (15 to 20) |
| Inhaler | 986 | 17 | 9 | 1.9 (1.3 to 2.6) | 13 (8 to 28) |
| Lozenge or tablet | 3,109 | 16 | 8 | 2.0 (1.6 to 2.5) | 12 (10 to 17) |
| Nasal spray | 887 | 24 | 12 | 2.0 (1.5 to 2.7) | 8 (6 to 14) |