1. Department of Mathematics and Statistics, Université de Montréal, Montreal, Canada
2. Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, Canada
3. Biostatistics Unit, Kaiser Permanente Washington Health Research Institute, Seattle, Washington, USA
4. Biostatistics Department, University of Washington, Seattle, Washington, USA
5. Lady Davis Institute for Medical Research, Jewish General Hospital, Montreal, Canada
6. Department of Neurology and Neurosurgery, McGill University, Montreal, Canada