title: External Validation of the Cincinnati Prehospital Stroke Severity Scale.
abstract: BACKGROUND
  The Cincinnati Prehospital Stroke Severity Scale (CPSSS) was recently developed to predict large-vessel occlusions (LVOs) in patients with acute ischemic stroke (AIS). In its derivation study, which consisted of patients enrolled in thrombolysis and endovascular therapy trials, the CPSSS had excellent discriminatory performance. We sought to externally validate the CPSSS in an independent cohort.
  
  
  METHODS
  Using our institution's prospective stroke registry, we calculated CPSSS scores for all patients diagnosed with AIS at Weill Cornell Medical Center in 2013 and 2014. The primary outcome was presence of LVO and the secondary outcome was a National Institutes of Health Stroke Scale (NIHSS) score of 15 or higher. Harrell's c-statistic was calculated to determine the CPSSS score's discriminatory performance. Using the previously defined cut-point of 2 or higher (range 0-4), we evaluated the test properties of the CPSSS for predicting study outcomes.
  
  
  RESULTS
  Among 751 patients with AIS, 664 had vessel imaging and were included in the final analysis. Of these patients, 80 (14.2%) had LVOs and 117 (17.6%) had an NIHSS score of 15 or higher. The median CPSSS score was 0 (interquartile range 0-1) and 133 patients (20%) had scores of 2 or higher. c-statistic was .85 (95% confidence interval [CI] .81-.90) for predicting LVO and .94 (95% CI .92-.97) for predicting an NIHSS score of 15 or higher. Using a cut-point of 2 or higher, the CPSSS was 70.0% sensitive and 86.8% specific for predicting LVO, and 87.2% sensitive and 94.3% specific for predicting an NIHSS score of 15 or higher.
  
  
  CONCLUSIONS
  In a cohort of patients with AIS treated at a tertiary-care stroke center, the CPSSS had reasonable sensitivity and specificity for predicting LVO and severe stroke. Future studies should aim to prospectively validate the score in emergency responders.
authors.affiliation: Department of Neurology, Weill Cornell Medical College, New York, New York. Electronic address: brk9023@nyp.org.
authors.forename: Benjamin R
authors.initials: BR
authors.lastname: Kummer
authors.affiliation: Feil Family Brain and Mind Research Institute, Weill Cornell Medical College, New York, New York.
authors.forename: Gino
authors.initials: G
authors.lastname: Gialdini
authors.affiliation: Department of Neurology, Weill Cornell Medical College, New York, New York.
authors.forename: Jennifer L
authors.initials: JL
authors.lastname: Sevush
authors.affiliation: Department of Neurology, Weill Cornell Medical College, New York, New York; Feil Family Brain and Mind Research Institute, Weill Cornell Medical College, New York, New York.
authors.forename: Hooman
authors.initials: H
authors.lastname: Kamel
authors.affiliation: Department of Neurosurgery, Weill Cornell Medical College, New York, New York.
authors.forename: Athos
authors.initials: A
authors.lastname: Patsalides
authors.affiliation: Department of Neurology, Weill Cornell Medical College, New York, New York; Feil Family Brain and Mind Research Institute, Weill Cornell Medical College, New York, New York.
authors.forename: Babak B
authors.initials: BB
authors.lastname: Navi
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002545:Brain Ischemia / Q000175:diagnosis* / Q000503:physiopathology / Q000628:therapy; D003243:Consciousness; D003661:Decision Support Techniques; D004185:Disability Evaluation; D004632:Emergency Medical Services; D005133:Eye Movements; D005260:Female; D006304:Health Status; D006801:Humans; D008297:Male; D008875:Middle Aged; D053580:Muscle Strength; D018482:Muscle, Skeletal / Q000503:physiopathology; D011237:Predictive Value of Tests; D011379:Prognosis; D012042:Registries; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012720:Severity of Illness Index; D020521:Stroke / Q000175:diagnosis* / Q000503:physiopathology / Q000628:therapy; D062606:Tertiary Care Centers; D034941:Upper Extremity
keywords: Stroke; acute stroke therapy; cerebral infarction; clinical prediction score; ischemic stroke; large-vessel occlusion