Ref (type)	Population	Outcome, Interventions	Results and statistical analysis	Effect size	Favours
All-cause mortality
[85] 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 Further report of reference [10]	All-cause mortality 5 years 44/1962 (2%) with smoking cessation intervention plus placebo 51/1964 (3%) with usual care	P = 0.47 (smoking cessation intervention plus placebo v usual care)		Not significant
[87] 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]	All-cause mortality 14.5 years 8.83/1000 person-years with smoking cessation intervention with or without ipratropium 10.83/1000 person-years with usual care	HR for mortality 1.18 95% CI 1.02 to 1.37 Combined analysis of smoking cessation programme with and without ipratropium (by intention-to-treat analysis) v usual care	Small effect size	smoking cessation intervention with or without ipratropium