[1] Med Spectrum Twente, Dept Pulm Med, POB 50 000, NL-7500 KA Enschede, Netherlands
[2] Univ Twente, Fac Behav Management & Social Sci, Tech Med Ctr, Dept Hlth Technol & Serv Res, Enschede, Netherlands
[3] Univ Twente, Fac Behav Management & Social Sci, Dept Res Methodol Measurement & Data Anal, Enschede, Netherlands
[4] Flinders Univ S Australia, Sch Med, Adelaide, SA, Australia
[5] Southern Adelaide Local Hlth Network, Dept Resp Med, Adelaide, SA, Australia