| Methods |
Country: USA (12 sites), Australia (1 site)
Recruitment: community volunteers and referrals |
| Participants |
1039 smokers (≥ 30 cpd) who had made a prior quit attempt, motivated to try again
50% male, average age 43, average cpd 38 |
| Interventions |
1. 42 mg nicotine patch (24 h, 6 weeks + 10 weeks tapering)
2. 35 mg nicotine patch
3. 21 mg nicotine patch
4. Placebo patch
Level of support: high (group behaviour therapy for 7 weeks, brief individual counselling at 5 dose‐tapering meetings. Self‐help booklet) |
| Outcomes |
Prolonged abstinence at 6 months (from 2 weeks post‐quit) verified at each follow‐up visit
(12‐month follow‐up only completed for 11/13 sites)
Validation: CO ≤ 10 ppm |
| Notes |
All doses pooled in Analysis 1.1 against placebo
6‐month abstinence rates used in analyses since not all centres completed 12‐month follow‐up due to sponsor termination of study. Denominators confirmed by author
Study was funded by National Institute on Drug Abuse, ALZA and Hoechst Marion Roussel |
| Risk of bias |
| Bias |
Authors' judgement |
Support for judgement |
| Random sequence generation (selection bias) |
Unclear risk |
Not stated |
| Allocation concealment (selection bias) |
Unclear risk |
Quote: "Subjects were randomly assigned in a double‐blind manner" |
| Blinding (performance bias and detection bias)
All outcomes |
Unclear risk |
Described as "double‐blind" but no further detail |
| Incomplete outcome data (attrition bias)
All outcomes |
High risk |
Early termination by sponsor, resulting in incomplete long‐term follow‐up data collection. Losses were included as failures |
