This research has emerged as a result of collaborations between Ontario and Saskatchewan-based researchers in the CCNA. The Saskatchewan Health Quality Council and the Rural Dementia Action Research (RaDAR) Team at the University of Saskatchewan have produced dementia prevalence and incidence estimates for Saskatchewan, with a focus on geographic variation and rural/urban differences. We propose to replicate the methodology that our Saskatchewan colleagues applied so that we can produce comparable estimates. For this research we will look at rural, urban and remote populations, estimating the 12-month prevalence and incidence of dementia in Ontario among those aged 45 or older for the years of 2002-03 through 2013-14.The analysis will require linkage between databases containing physician visits, hospitalizations, prescription drugs and long-term care.