| Methods |
Setting: Group Health Co‐operative, USA
Recruitment: Volunteers for a trial of medication |
| Participants |
1524 smokers ≥ 10 cigs/day; 43% M, av. age 45, av. cigs/day 23, 44% history of depression |
| Interventions |
Proactive
Factorial design, 300 mg/day and 150 mg/day bupropion doses collapsed. Prescription was mailed. No face‐to‐face contact during enrolment or treatment
1. Free & Clear proactive TC (4 brief calls), access to quitline and S‐H materials
2. Zyban Advantage Program (ZAP) tailored S‐H materials, single telephone call after TQD, access to Zyban (bupropion) support line |
| Outcomes |
Abstinence at 12 m (7‐day PP)
Validation: none |
| Notes |
Compares different intensities of TC. No dose/behavioural treatment interaction at 12 m so bupropion arms collapsed |
| Risk of bias |
| Bias |
Authors' judgement |
Support for judgement |
| Random sequence generation (selection bias) |
Low risk |
Randomisation procedure built into study database |
| Allocation concealment (selection bias) |
Low risk |
Procedure ensured concealment |
| Blinding of outcome assessment (detection bias)
All outcomes |
High risk |
Self‐reported outcomes from participants not blinded to treatment condition. Level of personal contact differed between arms |
| Incomplete outcome data (attrition bias)
All outcomes |
Low risk |
Loss to follow‐up at 12 m 17% Intervention, 12% Control, treated as smokers |
