1 Division of Infection, Immunity, and Respiratory Medicine, University of Manchester, Manchester University National Health Service Hospital Trust, Manchester, United Kingdom.
2 Respiratory Medicine Unit, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom.
3 Institute for Lung Health, National Institute for Health Research Leicester Biomedical Research Centre, Department of Respiratory and Infection Sciences, University of Leicester, Leicester, United Kingdom.
4 Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania.
5 Pulmonary and Critical Care Medicine, VA Ann Arbor Healthcare System, Ann Arbor, Michigan.
6 Division of Pulmonary and Critical Care Medicine, University of Michigan, Ann Arbor, Michigan.
7 Pulmonary and Critical Care Medicine, Weill Cornell Medical College, New York, New York.
8 COPD Patient-Powered Research Network, COPD Foundation, Washington, DC.