[1] Univ Copenhagen, Ctr Clin Educ, Copenhagen, Denmark
[2] Capital Reg Denmark, Copenhagen, Denmark
[3] Copenhagen Univ Hosp, Dept Surg Gastroenterol, Herlev, Denmark
[4] Univ Copenhagen, Gentofte Hosp, Dept Pulmonol, Hellerup, Denmark
[5] Leiden Univ, Med Ctr, Dept Pulmonol, Leiden, Netherlands
[6] Univ Amsterdam, Acad Med Ctr, Dept Pulmonol, NL-1105 AZ Amsterdam, Netherlands