1. Institute for Medical Information Processing; Biometry and Epidemiology (IBE); LMU Munich; Marchioninistr. 15 81377 Munich Germany
2. Institute for Medical Biometry and Statistics; Faculty of Medicine and Medical Center; University of Freiburg; Stefan-Meier-Str. 26 79104 Freiburg Germany
3. Department of Epidemiology; Biostatistics and Occupational Health; McGill University; 1020 Pine Avenue West Montreal, QC H3A 1A2 Canada