1. V Pfaffenrath, Leopoldstr. 59/11, 8000 Munich, FRG; R Dandekar, W Pöllmann, Neurologic Clinic, Ludwig-Maximilian University of Munich, Klinikum Grosshadern, Munich, FRG; ETh Mayer, Betriebsärztlicher Dienst, Goethestr. 26, 8000 Munich, FRG; G Hermann, GSF, Institute for Medical Informatics and Health Services Research, Munich-Neuherberg, FRG;