Oba 2007.

Methods	Study design: cost‐utility analysis (CUA) Time horizon: 1 year Currency used, year of study: US dollar (USD), 2005
Participants	Analytic perspective: third‐party payer’s Setting, country of study: primary and secondary care, USA Population: patients with moderate to severe COPD Effectiveness data and utility scores: data from 4 tiotropium versus placebo RCTs (Brusasco 2003; Casaburi 2002; Dusser 2006; Niewoehner 2005), 1 tiotropium versus salmeterol (Brusasco 2003) and 4 salmeterol versus placebo trials (Brusasco 2003; Chapman 2002; Jones 1997; Stockley 2006) Resource use and costs: treatment costs, hospital admission costs, ED visits, physician visits and unscheduled office visits. Costs for medications were based on the average wholesale price. Cost of hospitalisations from Solucient’s Medicare Database. Costs for inpatient physician visits and emergency department visits for COPD exacerbations were based on data from a study by Wilson 2000. The cost of antibiotic treatment was based on data from a study by Sin 2004.
Interventions	Intervention: tiotropium 18 μg once daily Control 1: salmeterol 50 μg twice daily Control 2: placebo
Outcomes	HRQL and hospitalisation rates, incremental QALY
Notes	Sensitivity analysis: worst case and best case using 95% CIs (for costs and benefits) were used as sensitivity analyses compared to placebo Funded by: not stated