Lung Diseases, Obstructive

• Holbæk Sygehus — Holbæk, Denmark
• Læge Poul Erik Holst — Holbæk, Denmark
• Lægehuset Tolskovvej — Kirke Hvalsø, Denmark
• Department of Orthopedics, Zealand University Hospital — Køge, Denmark

• Research Site — Berlin, Germany
• Research Site — Wellington, New Zealand
• Research Site — Harrow, United Kingdom
• Research Site — Manchester, United Kingdom

• Peking University People's Hospital — Beijing, China

• The University of Alabama at Birmingham Lung Health Center — Birmingham, Alabama, United States
• UCLA — Los Angeles, California, United States
• National Jewish Health — Denver, Colorado, United States
• Columbia University — New York, United States

• University of Alabama at Birmingham — Birmingham, Alabama, United States
• University of California San Diego — San Diego, California, United States
• The Lundquist Institute for Biomedical Innovation at Harbor-UCLA Medical Center — Torrance, California, United States
• National Jewish Health — Denver, Colorado, United States

• Children's Hospital of Philadelphia — Philadelphia, Pennsylvania, United States

• Can Tho Children's Hospital — Can Tho, Vietnam

• University of Physical Education in Krakow — Krakow, Poland

Not specified

Not specified