1. From Department of Rehabilitation Sciences (H.F., W.D.W., C.C.), Faculty of Physical Education and Physiotherapy, University of Leuven, Belgium; Biostatistical Center (G.V.), Faculty of Medicine, University of Leuven, Belgium; Department of the Rehabilitation Center of the Medical Clinic (G.C.S.), Bürgerspital, Solothurn, Switzerland; Department of Physical Medicine and Rehabilitation (C.K.), University Hospital Pellenberg, University of Leuven, Belgium; Department of Geriatrics (E.D.), University...