Characteristics of nontraumatic subarachnoid hemorrhage in the United States in 2003. Neurosurgery. 2007;61:1131 1137. 33. Ingall TJ, Whisnant JP, Wiebers DO, O Fallon WM. Has there been a decline in subarachnoid hemorrhage mortality? Stroke. 1989;20:718 724. 34. Koz k N, Hayashi M. Trends in the incidence of subarachnoid hemor- rhage in Akita Prefecture, Japan. J Neurosurg. 2007;106:234 238. 35. Sacco S, Totaro R, Toni D, Marini C, Cerone D, Carolei A. Incidence, case-fatalities and 10-year survival of subarachnoid hemorrhage in a population-based registry. Eur Neurol. 2009;62:155 160. 36. van Munster CE, von und zu Fraunberg M, Rinkel GJ, Rinne J, Koivisto T, Ronkainen A. Differences in aneurysm and patient characteristics between cohorts of Finnish and Dutch patients with subarachnoid hemor- rhage: time trends between 1986 and 2005. Stroke. 2008;39:3166 3171. 37. Koffijberg H, Buskens E, Granath F, Adami J, Ekbom A, Rinkel GJ, Blomqvist P. Subarachnoid haemorrhage in Sweden 1987 2002: regional incidence and case fatality rates. J Neurol Neurosurg Psychiatry. 2008;79:294 299. 38. Ostbye T, Levy AR, Mayo NE. Hospitalization and case-fatality rates for subarachnoid hemorrhage in Canada from 1982 through 1991: the Canadian Collaborative Study Group of Stroke Hospitalizations. Stroke. 1997;28:793 798. 39. Haberman S, Capildeo R, Rose FC. Sex differences in the incidence of cerebrovascular disease. J Epidemiol Community Health. 1981;35:45 50. 40. Nilsson OG, Lindgren A, St hl N, Brandt L, S veland H. Incidence of intracerebral and subarachnoid haemorrhage in southern Sweden. J Neurol Neurosurg Psychiatry. 2000;69:601 607. 41. Jacobs BS, Boden-Albala B, Lin IF, Sacco RL. Stroke in the young in the Northern Manhattan Stroke Study. Stroke. 2002;33:2789 2793. 42. 