The authors did a good job in the back ground section describing the previous studies.  It would been nicer it they can mention any studies comparing Ipatropium and Titropium

Methods
Good study design. sample size calculated.Multi center.  did not mention the race percentage in the demographic section. Does it matter to the authors?  Coe n guys, wake up
Demographic table 45% on anticholinergics. But in page 2 people on other anitchlinergic  were excluded?

smokers changed their pattern during the study. So the result are screwed??

Over all head to head Tiotropium and Placebo - P value not significant

Where are the benefits.
significant decrease in exacerbations, hospital admissions.

Interesting findings
Decreased Mi in Tiotropium group

final advice to COPD patients

Take the drug