Table 1.

Sample size calculations.

Primary confirmatory variable	Estimated value of outcome variable in exposure group	Estimated value of outcome variable in control group	Sample size exposed/ nonexposed	Adjusting sample size for anticipated dropouts
Symptomatic smokers defined by CAT ≥10	17%	42.8%	23/46	31/62
6MWT <450 m	11%	16.7%	260/520	347/694
Annual exacerbation rate	0.05	0.1	255/510	340/680