University of Potsdam, Center of Rehabilitation Research, Am Neuen Palais 10, 14469, Potsdam, Germany. heidler@brandenburgklinik.de. Brandenburg Klinik Bernau, Bernau bei Berlin, Germany. heidler@brandenburgklinik.de. University of Potsdam, Center of Rehabilitation Research, Am Neuen Palais 10, 14469, Potsdam, Germany. Brandenburg Klinik Bernau, Bernau bei Berlin, Germany. Kliniken Beelitz, Beelitz, Germany. MEDIAN Klinik Berlin-Kladow, Berlin, Germany. MEDIAN Klinik Grünheide, Grünheide (Mark), Germany. Vivantes Klinikum Spandau, Berlin, Germany.