1. Department of Medical Bioinformatics, University Medical Center Göttingen , 37077 Niedersachsen, Germany
2. Peter L. Reichertz Institute for Medical Informatics of TU Braunschweig and Hannover Medical School, Hannover Medical School , 30625 Hannover, Germany
3. Department of Medical Informatics, University Medical Center Göttingen , 37075 Niedersachsen, Germany