Ref (type)	Population	Outcome, Interventions	Results and statistical analysis	Effect size	Favours
Adverse effects
[10] [90] RCT 3-armed trial	5887 smokers, aged 35 to 60 years, with spirometric signs of early COPD; mean pre-bronchodilator FEV1 2640 mL, mean of 30 cigarettes smoked/day In review [83]	Adverse effects (any) with smoking cessation intervention plus ipratropium with smoking cessation alone
[92] RCT	404 people with mild or moderate COPD, smoking an average of 28 cigarettes a day, mean age 54 years In review [83]	Proportion of people discontinuing treatment because of adverse effects 6 months 7% with bupropion (slow-release 150 mg twice daily) plus counselling 6% with placebo plus counselling Absolute numbers not reported	Significance not assessed
[92] RCT	404 people with mild or moderate COPD, smoking an average of 28 cigarettes a day, mean age 54 years In review [83]	Proportion of people with a serious adverse event 6 months 0.5% with bupropion (slow-release 150 mg twice daily) plus counselling 2.5% with placebo plus counselling Absolute numbers not reported	Significance not assessed