Description of the Ability to Learn How to Handle Inhaler Devices in COPD

The correct use of inhaler devices is an inclusion criterion in COPD clinical trials. In real life, patients may make many errors using their own inhaler device, which may alter the positive effects observed in clinical trials. The main objective of this study is to describe the handling of inhaler devices (indacaterol-glycopyrronium Breezhaler®, tiotropium Respimat® and salmeterol-fluticasone Diskus®) in patients with COPD. All participants will receive each of the three treatments (Seretide® Diskus® 500/550 μg, Ultibro® Breezhaler® 110/50 μg and Spiriva® Respimat® 2,5 μg). Each treatment will be given daily for one week, followed by a 7-day washout period. On day 1 of each treatment period, the patient will have clinical examination, lung function testing (FEV1) and 2 video recordings: * Video recording #1: inhalation (one puff) without any instruction of use, * Video recording #2: inhalation (one puff) after reading the patient information leaflet. At the end of the visit, the patient will watch a standardized video demonstrating correct inhaler technique. On day 7 of each treatment period, the patient will have clinical examination, lung function testing (FEV1) and 1 video recording of inhaler device use (one puff). 30 days after the last visit, the patient will have a phone contact to collect the adverse events.