Both doses of tiotropium resulted in significant improvement compared with placebo in the co-primary efficacy end points at the end of week @ ( change from baseline in percent-predicted FEV@ AUC@-@h : @ g : @ % , @ % confidence interval @-@ @ , p = @ ; @ g : @ % , @ % confidence interval @-@ @ , p = @ ; in percent-predicted trough FEV@ @ g : @ % , p = @ ; @ g : @ % , p = @ ) .