title: External Validation of a Case-Mix Adjustment Model for the Standardized Reporting of 30-Day Stroke Mortality Rates in China.
abstract: OBJECTIVE
  A case-mix adjustment model has been developed and externally validated, demonstrating promise. However, the model has not been thoroughly tested among populations in China. In our study, we evaluated the performance of the model in Chinese patients with acute stroke.
  
  
  METHODS
  The case-mix adjustment model A includes items on age, presence of atrial fibrillation on admission, National Institutes of Health Stroke Severity Scale (NIHSS) score on admission, and stroke type. Model B is similar to Model A but includes only the consciousness component of the NIHSS score. Both model A and B were evaluated to predict 30-day mortality rates in 13,948 patients with acute stroke from the China National Stroke Registry. The discrimination of the models was quantified by c-statistic. Calibration was assessed using Pearson's correlation coefficient.
  
  
  RESULTS
  The c-statistic of model A in our external validation cohort was 0.80 (95% confidence interval, 0.79-0.82), and the c-statistic of model B was 0.82 (95% confidence interval, 0.81-0.84). Excellent calibration was reported in the two models with Pearson's correlation coefficient (0.892 for model A, p<0.001; 0.927 for model B, p = 0.008).
  
  
  CONCLUSIONS
  The case-mix adjustment model could be used to effectively predict 30-day mortality rates in Chinese patients with acute stroke.
authors.affiliation: Department of Neurology, The Second Hospital, Hebei Medical University, Shijiazhuang, China.
authors.forename: Ping
authors.initials: P
authors.lastname: Yu
authors.affiliation: Tiantan Clinical Trial and Research Center for Stroke, Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.|Beijing Key Laboratory of Translational Medicine for Cerebrovascular Disease, Beijing, China.
authors.forename: Yuesong
authors.initials: Y
authors.lastname: Pan
authors.affiliation: Tiantan Clinical Trial and Research Center for Stroke, Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.|China National Clinical Research Center for Neurological Diseases, Beijing, China.|Vascular Neurology, Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.
authors.forename: Yongjun
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Tiantan Clinical Trial and Research Center for Stroke, Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.
authors.forename: Xianwei
authors.initials: X
authors.lastname: Wang
authors.affiliation: China National Clinical Research Center for Neurological Diseases, Beijing, China.|Neuro-intensive Care Unit, Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.
authors.forename: Liping
authors.initials: L
authors.lastname: Liu
authors.affiliation: China National Clinical Research Center for Neurological Diseases, Beijing, China.|Vascular Neurology, Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.
authors.forename: Ruijun
authors.initials: R
authors.lastname: Ji
authors.affiliation: Tiantan Clinical Trial and Research Center for Stroke, Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.
authors.forename: Xia
authors.initials: X
authors.lastname: Meng
authors.affiliation: Tiantan Clinical Trial and Research Center for Stroke, Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Jing
authors.affiliation: Department of Neurology, Tangshan Gongren Hospital, Hebei Medical University, Tangshan, Hebei, China.
authors.forename: Xu
authors.initials: X
authors.lastname: Tong
authors.affiliation: Department of Neurology, The Second Hospital, Hebei Medical University, Shijiazhuang, China.
authors.forename: Li
authors.initials: L
authors.lastname: Guo
authors.affiliation: Tiantan Clinical Trial and Research Center for Stroke, Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.|China National Clinical Research Center for Neurological Diseases, Beijing, China.|Vascular Neurology, Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.
authors.forename: Yilong
authors.initials: Y
authors.lastname: Wang
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001281:Atrial Fibrillation / Q000453:epidemiology / Q000401:mortality / Q000503:physiopathology; D002545:Brain Ischemia / Q000453:epidemiology / Q000401:mortality* / Q000503:physiopathology; D002681:China; D050171:Dyslipidemias / Q000503:physiopathology; D005260:Female; D006760:Hospitalization; D006801:Humans; D008297:Male; D008875:Middle Aged; D009026:Mortality; D011379:Prognosis; D012015:Reference Standards; D012720:Severity of Illness Index; D020521:Stroke / Q000453:epidemiology / Q000401:mortality* / Q000503:physiopathology