title: Accuracy of Death Certificates and Assessment of Factors for Misclassification of Underlying Cause of Death.
abstract: BACKGROUND
  Cause of death (COD) information taken from death certificates is often inaccurate and incomplete. However, the accuracy of Underlying CODs (UCODs) recorded on death certificates has not been comprehensively described when multiple diseases are present.
  
  
  METHODS
  A total of 450 consecutive autopsies performed at a geriatric hospital in Japan between February 2000 and August 2002 were studied. We evaluated the concordance rate, sensitivity, and specificity of major UCODs (cancer, heart disease, and pneumonia) reported on death certificates compared with a reference standard of pathologist assessment based on autopsy data and clinical records. Logistic regression analysis was performed to assess the effect of sex, age, comorbidity, and UCODs on misclassification.
  
  
  RESULTS
  The concordance rate was relatively high for cancer (81%) but low for heart disease (55%) and pneumonia (9%). The overall concordance rate was 48%. Sex and comorbidity did not affect UCOD misclassification rates, which tended to increase with patient age, although the association with age was also not significant. The strongest factor for misclassification was UCODs (P < 0.0001). Sensitivity and specificity for cancer were very high (80% and 96%, respectively), but sensitivity for heart disease and pneumonia was 60% and 46%, respectively. Specificity for each UCOD was more than 85%.
  
  
  CONCLUSIONS
  Researchers should be aware of the accuracy of COD data from death certificates used as research resources, especially for cases of elderly patients with pneumonia.
authors.affiliation: Department of Medical Informatics, Center for Information, Jichi Medical University.
authors.forename: Makiko Naka
authors.initials: MN
authors.lastname: Mieno
authors.forename: Noriko
authors.initials: N
authors.lastname: Tanaka
authors.forename: Tomio
authors.initials: T
authors.lastname: Arai
authors.forename: Takuya
authors.initials: T
authors.lastname: Kawahara
authors.forename: Aya
authors.initials: A
authors.lastname: Kuchiba
authors.forename: Shizukiyo
authors.initials: S
authors.lastname: Ishikawa
authors.forename: Motoji
authors.initials: M
authors.lastname: Sawabe
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002423:Cause of Death; D003644:Death Certificates; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D014041:Tokyo / Q000453:epidemiology