Pulmonary Disease, Chronic Obstructive

• Des Moines VA — Des Moines, Iowa, United States
• IA City VA — Iowa City, Iowa, United States
• Minneapolis VAMC — Minneapolis, Minnesota, United States
• Omaha VAMC — Omaha, Nebraska, United States

• Radboud University Nijmegen Medical Centre, Department of Primary and Community Care — Nijmegen, Netherlands

Not specified

• Rady Children's Hospital — San Diego, California, United States

• Brigham and Women's Hospital — Boston, Massachusetts, United States

• Faculdade Evangelica do Paraná — Curitiba, Paraná, Brazil

• University Hospital Dominique Larrey — Limoges, France
• Rehabilitation Department of Cyr Voisin — Loos, France
• University Hospital Arnaud de Villeneuve — Montpellier, France
• Hospital la Pitiè-Salpétrière — Paris, France

• Research Site — Birmingham, Alabama, United States
• Research Site — Jasper, Alabama, United States
• Research Site — Phoenix, Arizona, United States
• Research Site — Buena Park, California, United States

• West China Hospital — Chengdu, Sichuan, China

• Baylor College of Medicine — Houston, Texas, United States