BACKGROUND: Inhaler usability and deposition differ between devices. Change of device may therefore have an impact on clinical and economic outcomes. OBJECTIVE: To characterize clinical and economic asthma outcomes surrounding the change from a dry powder inhaler (DPI) to a pressurized metered-dose inhaler (pMDI) for fixed-dose combination inhaled corticosteroid/long-acting β agonist (FDC ICS/LABA) treatment. METHODS: Three retrospective cohort substudies using 2010 to 2015 data from the Korean Health Insurance and Review Assessment Service database were performed. Patients with asthma who received an FDC ICS/LABA pMDI for the first time after initially being on FDC ICS/LABA DPI were included. The following outcomes were assessed: (1) persi...