Killen 2006

Methods	Setting: clinic, USA Recruitment: community volunteers
Participants	362 smokers ≥ 10 cigs/day, no current major depression 46% female, average age 45, average cigs/day 20, 25% previous bupropion use
Interventions	All participants received open‐label combination pharmacotherapy of bupropion 300 mg for 11 weeks, nicotine patch for 10 weeks. TQD day 7, 30‐min individual relapse prevention skills training at 6 clinic visits 1. Bupropion 150 mg for 14 weeks 2. 2 weeks tapering bupropion, then placebo Both arms had 4 further clinic visits during extended therapy
Outcomes	Abstinence at 12 months (6 months post‐EOT) (continuous). PP and 7‐day relapse‐free outcomes also reported Validation: CO (10 people not required to provide samples)
Notes	New for 2009 update PP outcomes favoured placebo, but no outcomes showed significant effects Approximately 52% were quit at the end of baseline therapy
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Preassigned random sequence stratified by gender, before open‐label phase
Allocation concealment (selection bias)	Low risk	Not explicitly concealed but judged probable that it was
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Blinded drugs provided to investigator; " ... [the pharmaceutical company]... packaged the treatment and then shipped the blinded drug to the investigator"
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Treatment condition blinded, biochemical validation used
Incomplete outcome data (attrition bias) All outcomes	Low risk	10% lost to follow‐up, included in ITT analysis