Oostenbrink 2005.

Methods	Study design: cost‐utility analysis (CUA), 3‐state Markov model Time horizon: 1 year Currency used, year of study: Euro (EUR), 2004
Participants	Analytic perspective: healthcare system in Netherlands or Canada Setting, country of study: primary and secondary care, Netherlands and Canada Population: patients with COPD Effectiveness data: data from 6 RCTs (Brusasco 2003; Casaburi 2002; Vincken 2002) Utility scores: utility values per disease state were based on empiric data from an observational study in patients with COPD classified into the GOLD stages (Borg 2004) Resource use and costs: treatments costs, hospitalisations, healthcare visits, physician visits, etc. Resource utilisation captured from 2 ipratropium‐controlled RCTs in the Netherlands with list prices used for drug costs (Oostenbrink 2004; Oostenbrink 2004a). For Canada this was collected from a prospective multi‐centre observational study (no reference stated) with drug costs from the Ontario Drug Benefit Formulary (Canada)
Interventions	Intervention: tiotropium 18 μg once daily Control 1: salmeterol 50 μg twice daily Control 2: ipratropium 40 μg 4 times daily
Outcomes	Exacerbations, QALM
Notes	Sensitivity analysis: Monte Carlo simulation, probabilistic sensitivity analysis and one‐way sensitivity analysis based on either severity of COPD, exacerbation rate, utility values, oxygen therapy Funded by: Boehringer Ingelheim (manufacturer of tiotropium)