1 Norwegian Advisory Unit onHome Mechanical VentilationThoracic Department Haukeland University HospitalBergen, NorwayDepartment of PhysiotherapyHaukeland University HospitalBergen, NorwayThe Faculty of Health and Social SciencesWestern Norway University of Applied SciencesBergen, Norway tiina.andersen@helse-bergen.no.
2 Norwegian Advisory Unit onHome Mechanical VentilationThoracic DepartmentHaukeland University HospitalBergen, NorwayDepartment of PediatricsHaukeland University HospitalBergen, NorwayThe Faculty of MedicineDepartment of Clinical ScienceUniversity of BergenBergen, Norway.