1 Department of Medical Information Processing, Biometry and Epidemiology (IBE), Ludwig-Maximilians-University of Munich, Marchioninistr. 15, 81377, Munich, Germany. boulesteix@ibe.med.uni-muenchen.de.
2 Department of Biometry and Data Management, Leibniz Institute for Prevention Research and Epidemiology - BIPS, Achterstraße 30, 28359, Bremen, Germany.