1 CTU Bern, University of Bern, Finkenhubelweg 11, 3012 Bern, Switzerland. Electronic address: strobe@ispm.unibe.ch.
2 Department of Epidemiology, UNC Gillings School of Global Public Health, University of North Carolina, 170 Rosenau Hall, CB #7400, 135 Dauer Drive, Chapel Hill, NC 27599-7400, USA.
3 Centre d'épidemiologie clinique, Codirector Cochrane, Switzerland; Centre Hospitalier Universitaire Vaudois (CHUV) and University of Lausanne, IUMSP - Institut universitaire de médecine sociale et préventive, Biopôle 2, Route de la Corniche 10, CH-1010 Lausanne, Switzerland.
4 Centre for Statistics in Medicine, University of Oxford, Botnar Research Centre, Windmill Road, OX3 7LD Oxford, UK.
5 Institute of Social and Preventive Medicine, University of Bern, Finkenhubelweg 11 3012 Bern, Switzerland.