Department of Surgery, University Hospital Basel, Basel, Switzerland
Basel Institute for Clinical Epidemiology and Biostatistics, University Hospital Basel, Basel, Switzerland
Department of Biostatistics, The University of Liverpool, Liverpool, United Kingdom.
Disclosure: There is no funding related to this investigation. There are no conflicts of interest to declare. Rachel Rosenthal is an employee of F. Hoffmann-La Roche Ltd since May 1, 2014. This study was conducted before Rachel Rosenthal joined F. Hoffmann-La Roche Ltd and has no connection to her employment by the company. Heiner C. Bucher is supported by funds from Santésuisse and the Gottfried and Julia Bangerter-Rhyner Foundation.