“…T he epidemiology of ESRD has been studied extensively using large databases such as the United States Renal Data System and similar registries in Canada, Europe, Australia, and New Zealand (1)(2)(3)(4). In contrast, the epidemiology of acute renal failure (ARF) in hospitalized patients is less well understood, having been derived largely from single-center retrospective studies that used detailed review of medical records (5)(6)(7).…”