Published on in Vol 22, No 3 (2020): March
Preprints (earlier versions) of this paper are
available at
https://preprints.jmir.org/preprint/15070, first published
.

1 Institute of Anesthesiology, University Hospital Zurich , Zurich , CH
2 Department of Biostatistics, Epidemiology, Biostatistics and Prevention Institute, University of Zurich, Zurich , CH