Interrater reliability of an etiologic classification of ischemic stroke

• Published in: Stroke (1970) Vol. 26; no. 1; pp. 46 - 51
• Main Authors: JOHNSON, C. J, KITTNER, S. J, MCCARTER, R. J, SLOAN, M. A, STERN, B. J, BUCHHOLZ, D, PRICE, T. R
• Format: Journal Article
• Language: English
• Published: Hagerstown, MD Lippincott Williams & Wilkins 1995; American Heart Association, Inc
• Subjects: Adolescent; Adult; Arteriosclerosis - complications; Arteriosclerosis - epidemiology; Baltimore - epidemiology; Biological and medical sciences; Brain Ischemia - classification; Brain Ischemia - epidemiology; Brain Ischemia - etiology; Cardiovascular Diseases - epidemiology; Cardiovascular Diseases - etiology; Cerebral Hemorrhage - epidemiology; Cerebral Hemorrhage - etiology; Contraceptives, Oral, Hormonal; District of Columbia - epidemiology; Female; Humans; Incidence; Male; Medical sciences; Migraine Disorders - complications; Migraine Disorders - epidemiology; Neurology; Observer Variation; Registries; Vascular diseases and vascular malformations of the nervous system; District of Columbia; Baltimore; Performance evaluation; Human; Nervous system diseases; Stroke; Cardiovascular disease; Cerebral disorder; Vascular disease; Ischemia; Etiology; Central nervous system disease; Classification; Cerebrovascular disease; Brain (vertebrata)
• ISSN: 0039-2499; 1524-4628
• DOI: 10.1161/01.STR.26.1.46

Precise identification of the cause of stroke is critical to research and clinical practice. Published series of ischemic stroke show considerable variation in the proportion of cases classified as atherosclerotic large-vessel disease, lacunar infarct, cardioembolic stroke, stroke of other known cause, and stroke of undetermined etiology. We describe the development and use of an etiology-specific classification of ischemic stroke. The interrater reliability of the classification is then evaluated. A total of 160 cases of ischemic strokes in young adults were reviewed by paired neurologists who assigned cases to prioritized categories. The results of paired ratings were evaluated for each of the potential causes. Interrater agreement was assessed by means of kappa, which is the chance-adjusted percent agreement. For standard pairs, kappa was fair to good for all causes except lacunar stroke (kappa = 0.31); however, pair-to-pair variation was greatest for lacunar strokes. Strokes of undetermined cause and hematologic/other cause were of borderline fair reliability. The utility of a stroke classification system is dependent on its intended use. An etiologic classification is useful in studies of the epidemiology and pathophysiological basis of stroke. Fair to good reliability for an etiologic classification of stroke can be obtained when criteria are explicit.