[1] Ludwig Boltzmann Inst Lung Hlth, Vienna, Austria
[2] Sigmund Freud Univ, Fac Med, Vienna, Austria
[3] Maastricht Univ, Dept Resp Med, MUMC, Maastricht, Netherlands
[4] Politecn Milano Univ, Dept Elect Informat & Bioingn, Milan, Italy
[5] Restech Srl, Milan, Italy
[6] Vienna Healthcare Grp, Dept Resp & Pulm Dis, Clin Penzing, Vienna, Austria
[7] Sigmund Freud Univ, Fac Med, Vienna, Austria
[8] Univ Vermont, Dept Pulm & Crit Care Med, Burlington, VT USA