Dataset from A Randomized, Double-blind, Parallel Group Trial Comparing 12 Weeks Treatment With Tiotropium 18 mcg Daily to Combivent MDI 2 Actuations Qid in COPD Patients Previously Prescribed Combivent MDI

The objective of this study is to evaluate the efficacy and safety of 12 weeks treatment with tiotropium HandiHaler 18 micrograms (mcg) daily compared to Combivent Metered Dose Inhaler (MDI) Chlorofluorocarbon Inhalation Aerosol 2 actuations four times a day in Chronic Obstructive Pulmonary Disease (COPD) patients currently prescribed Combivent® MDI.