Tønnesen 2000.

Study characteristics
Methods	Study design: parallel RCT Country: Denmark Recruitment: referrals to lung clinic
Participants	446 smokers ≥ 10 cigarettes per day 48% men, average age 49, average cigarettes per day 18
Interventions	1) 5 mg nicotine patch (placebo) 2) 15 mg (16‐hour) nicotine patch for 12 weeks (up to 9 months on request) 3) Nicotine inhaler (4 to 12/day ad lib) 4) Combination, 15 mg patch and inhaler
Outcomes	Sustained abstinence at 12 months, (from week 2, paper also reports PPA and with slips rates) Validation: CO < 10 ppm at all visits Adverse events: measured at every follow‐up to 12 months (note: treatment could continue to 12 months)
Notes	This study was supported by a grant from Pharmacia & Upjohn, Helsingborg, Sweden and the Danish Lung Foundation. Conflicts of interest: not reported
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: "a computer‐generated list with random numbers"
Allocation concealment (selection bias)	Unclear risk	Not stated
Blinding (performance bias and detection bias) All outcomes	Unclear risk	Not used ‐ open‐label trial
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Non‐attenders or lost to follow‐up were included as smokers