title: Validation of Stroke Diagnosis in the National Registry of Hospitalized Patients in the Czech Republic.
abstract: BACKGROUND
  Stroke is a common cause of mortality and morbidity in Eastern Europe. However, detailed epidemiological data are not available. The National Registry of Hospitalized Patients (NRHOSP) is a nationwide registry of prospectively collected data regarding each hospitalization in the Czech Republic since 1998. As a first step in the evaluation of stroke epidemiology in the Czech Republic, we validated stroke cases in NRHOSP.
  
  
  METHODS
  Any hospital in the Czech Republic with a sufficient number of cases was included. We randomly selected 10 of all 72 hospitals and then 50 patients from each hospital in 2011 stratified according to stroke diagnosis (International Classification of Diseases Tenth Revision [ICD-10] cerebrovascular codes I60, I61, I63, I64, and G45). Discharge summaries from hospitalization were reviewed independently by 2 reviewers and compared with NRHOSP for accuracy of discharge diagnosis. Any disagreements were adjudicated by a third reviewer.
  
  
  RESULTS
  Of 500 requested discharge summaries, 484 (97%) were available. Validators confirmed diagnosis in NRHOSP as follows: transient ischemic attack (TIA) or any stroke type in 82% (95% confidence interval [CI], 79-86), any stroke type in 85% (95% CI, 81-88), I63/cerebral infarction in 82% (95% CI, 74-89), I60/subarachnoid hemorrhage in 91% (95% CI, 85-97), I61/intracerebral hemorrhage in 91% (95% CI, 85-96), and G45/TIA in 49% (95% CI, 39-58). The most important reason for disagreement was use of I64/stroke, not specified for patients with I63.
  
  
  CONCLUSIONS
  The accuracy of coding of the stroke ICD-10 codes for subarachnoid hemorrhage (I60) and intracerebral hemorrhage (I61) included in a Czech Republic national registry was high. The accuracy of coding for I63/cerebral infarction was somewhat lower than for ICH and SAH.
authors.affiliation: Department of Neurology, St. Anne's University Hospital and Faculty of Medicine, Masaryk University, Brno, Czech Republic; International Clinical Research Center, St Anne's University Hospital, Brno, Czech Republic; Department of Neurology, Mayo Clinic, Rochester, MN.
authors.forename: Petra
authors.initials: P
authors.lastname: Sedova
authors.affiliation: Department of Neurology, Mayo Clinic, Rochester, MN. Electronic address: brown@mayo.edu.
authors.forename: Robert D
authors.initials: RD
authors.lastname: Brown
authors.affiliation: Institute for Health Information and Statistics of the Czech Republic, Prague, Czech Republic.
authors.forename: Miroslav
authors.initials: M
authors.lastname: Zvolsky
authors.affiliation: International Clinical Research Center, St Anne's University Hospital, Brno, Czech Republic.
authors.forename: Pavla
authors.initials: P
authors.lastname: Kadlecova
authors.affiliation: Department of Neurology, St. Anne's University Hospital and Faculty of Medicine, Masaryk University, Brno, Czech Republic; International Clinical Research Center, St Anne's University Hospital, Brno, Czech Republic.
authors.forename: Tomas
authors.initials: T
authors.lastname: Bryndziar
authors.affiliation: Department of Neurology, St. Anne's University Hospital and Faculty of Medicine, Masaryk University, Brno, Czech Republic; International Clinical Research Center, St Anne's University Hospital, Brno, Czech Republic.
authors.forename: Ondrej
authors.initials: O
authors.lastname: Volny
authors.affiliation: Department of Neurology, St. Anne's University Hospital and Faculty of Medicine, Masaryk University, Brno, Czech Republic; International Clinical Research Center, St Anne's University Hospital, Brno, Czech Republic.
authors.forename: Viktor
authors.initials: V
authors.lastname: Weiss
authors.affiliation: Department of Neurology, University Hospital Brno and Faculty of Medicine, Masaryk University, Brno, Czech Republic.
authors.forename: Josef
authors.initials: J
authors.lastname: Bednarik
authors.affiliation: Department of Neurology, St. Anne's University Hospital and Faculty of Medicine, Masaryk University, Brno, Czech Republic; International Clinical Research Center, St Anne's University Hospital, Brno, Czech Republic.
authors.forename: Robert
authors.initials: R
authors.lastname: Mikulik
mesh_terms: D002544:Cerebral Infarction; D018153:Czech Republic / Q000453:epidemiology; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data*; D006801:Humans; D038801:International Classification of Diseases; D002546:Ischemic Attack, Transient / Q000150:complications / Q000453:epidemiology; D008297:Male; D011446:Prospective Studies; D012042:Registries; D015203:Reproducibility of Results; D020521:Stroke / Q000175:diagnosis* / Q000453:epidemiology* / Q000209:etiology; D013345:Subarachnoid Hemorrhage
keywords: Czech Republic; Stroke; epidemiology; registry; validation