1. D. Moher, PhD, Ottawa Methods Centre, Ottawa Hospital Research Institute, The Ottawa Hospital, General Campus, Critical Care Wing (Eye Institute), 6th Floor, 501 Smyth Road, Ottawa, Ontario K1H 8L6, Canada. dmoher@ohri.ca
2. A. Liberati, MD, DrPH, Università di Modena e Reggio Emilia and Centro Cochrane Italiano, Istituto Ricerche Farmacologiche Mario Negri, Via La Masa 19, 20156 Milan, Italy.
3. J. Tetzlaff, BSc, Ottawa Methods Centre, Ottawa Hospital Research Institute, The Ottawa Hospital, General Campus, Critical Care Wing (Eye Institute), 6th Floor, 501 Smyth Road, Ottawa, Ontario K1H 8L6, Canada.
4. D.G. Altman, DSc, Centre for Statistics in Medicine, University of Oxford, Wolfson College Annexe, Linton Road, Oxford OX2 6UD, United Kingdom.