The aim of the study is to develop a new patient-reported outcome (PRO) questionnaire measuring the impact of an acute exacerbation on daily lives of patients with chronic obstructive pulmonary disease (COPD). This questionnaire will aim to detect an acute exacerbation and resolution of exacerbation from the patient's perspective. At a later stage of development, this questionnaire will be able to measure the effect of anti bacterials in the treatment of acute exacerbations of COPD (AECOPD). This study will evaluate the factor structure, validity, reliability, and responsiveness of the GSK questionnaire in subjects who experience acute exacerbations of their COPD.