1. PHARMO Institute UtrechtThe Netherlands
2. Department of Pulmonary DiseasesMartini Hospital GroningenThe Netherlands
3. Department of Pulmonary DiseasesRijnstate Hospital ArnhemThe Netherlands
4. Department of Pulmonary DiseasesUniversity Medical Center Utrecht UtrechtThe Netherlands
5. Department of Policy & Health ManagementPharmacoepidemiology Erasmus MC, PO Box 2040, 3000 CA RotterdamThe Netherlands