Boswell, Scott Angiogram-negative subarachnoid hemorrhage: outcomes data and review of the literature. [electronic resource] - Journal of stroke and cerebrovascular diseases : the official journal of National Stroke Association Aug 2013 - 750-7 p. digital Publication Type: Journal Article; Meta-Analysis; Review ISSN: 1532-8511 Standard No.: 10.1016/j.jstrokecerebrovasdis.2012.02.001 doi Subjects--Topical Terms: Brain Ischemia--etiologyCerebral AngiographyDisease ProgressionFemaleHeadache--etiologyHumansHydrocephalus--etiologyMaleMiddle AgedOdds RatioPredictive Value of TestsPrognosisRecurrenceRetrospective StudiesRisk FactorsSubarachnoid Hemorrhage--complicationsTime FactorsVasospasm, Intracranial--etiology