1. Section of Respiratory Medicine; Hvidovre University Hospital; Hvidovre Denmark
2. Longitudinal Studies Section; Translational Gerontology Branch; National Institute on Aging; Baltimore MD USA
3. Department of Research & Education; CIRO+; Centre of Expertise for Chronic Organ Failure; Horn The Netherlands
4. Faculty of Medicine and Life Sciences; REVAL - Rehabilitation Research Center; BIOMED - Biomedical Research Institute; Hasselt University; Diepenbeek Belgium