UNIFIED NEUROLOGICAL STROKE SCALE IS VALID IN ISCHEMIC AND HEMORRHAGIC STROKE

Background and Purpose The growing interest in testing new therapeutic agents for acute brain injury has lead to increased use of stroke sca les. The reliability and validity of these measures need to be examine d more completely. We used structural equation modeling, a technique t hat merges the analytic procedures of factor analysis and multiple reg ression, to examine the reliability and construct validity of the Midd le Cerebral Artery Neurological Scale and the Scandinavian Neurologica l Stroke Scale used together as the Unified Neurological Stroke Scale. We also analyzed the predictive validity, sensitivity, and specificit y of the scales in predicting mortality and functional outcome. Method s We prospectively studied 84 consecutive patients admitted to a neuro logy/neurosurgery intensive care unit with intracerebral hemorrhage (n =30), subarachnoid hemorrhage (n=15), ischemic stroke (n=15), and trau matic brain injury (n=24). Patients were evaluated within 24 hours of admission and at 48-hour intervals until intensive care unit discharge . A total of 386 assessments were obtained. The Functional Independenc e Measure was administered by telephone 3 months after hospital discha rge. Results High levels of reliability and construct validity were ob served for the majority of the Unified Stroke Scale items. Facial pals y and eye movement items had the lowest reliability and validity. Both the Middle Cerebral Artery and Scandinavian Scales were significant p redictors of outcome. Sensitivity and specificity varied by diagnosis. Predictive validity of functional outcome was best in groups with isc hemic and hemorrhagic stroke rather than traumatic brain injury and su barachnoid hemorrhage. Conclusions The Unified Stroke Scale demonstrat es reliability and construct and predictive validity, and its use is s upported in ischemic and hemorrhagic stroke. Structural equation model ing is an appropriate technique for use with scales of this type.