[1] Univ Groningen, Univ Med Ctr Groningen, Dept Pulm Dis, Dept Home Mech Ventilat, NL-9700 RB Groningen, Netherlands
[2] Univ Groningen, Univ Med Ctr Groningen, Ctr Rehabil, NL-9700 RB Groningen, Netherlands
[3] Univ Groningen, Univ Med Ctr Groningen, Dept Epidemiol, NL-9700 RB Groningen, Netherlands
[4] Univ Groningen, Univ Med Ctr Groningen, Dept Crit Care, NL-9700 RB Groningen, Netherlands