1. Department of Clinical Epidemiology and Biostatistics (G.L., L.M., S.Z., J.C., L.T.), Hamilton, Ontario, Canada L8S 4L8
2. Department of Psychiatry and Behavioural Neurosciences (Z.S.), Hamilton, Ontario, Canada L8S 4L8
3. Post Graduate Program in Epidemiology (M.F.), Universidade Federal do Rio Grande do Sul, Porto Alegre 90040-060, Brazil
4. St Joseph's Hospital (J.D.A., J.C., L.T.), McMaster University, Hamilton, Ontario, Canada L8N 4A6
5. Division of Geriatric Medicine, Department of Medicine (A.P.), McMaster University, Hamilton, Ontario, Canada L8S 4L8