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September 25, 2013

High-Stakes Diagnostic Decision Rules for Serious Disorders: The Ottawa Subarachnoid Hemorrhage Rule

Author Affiliations
  • 1Department of Neurology, The Johns Hopkins University School of Medicine, Baltimore, Maryland
  • 2Harvard Medical School, Boston, Massachusetts
  • 3Department of Emergency Medicine, Beth Israel Deaconess Medical Center, Boston
JAMA. 2013;310(12):1237-1239. doi:10.1001/jama.2013.278019

Diagnostic errors lead to death or disability for an estimated 150 000 patients in the United States each year.1 The emergency department is a known high-risk location for misdiagnosis.2 Missed ischemic stroke and brain hemorrhage are recognized sources of diagnostic error, with approximately 9% of cerebrovascular events missed at first emergency department contact,3 including an estimated 20% of subarachnoid hemorrhages in patients presenting with normal mental status.4 Because effective treatments are available, diagnostic delays increase morbidity and mortality 3- to 8-fold,4,5 so accurate early diagnosis is important.