Using cancer registry data: agreement in cause-of-death data between the Ontario Cancer Registry and a longitudinal study of breast cancer patients

Chronic Dis Can. 2009;30(1):16-9.


Data from the Ontario Cancer Registry (OCR) were compared with data from a multi-centred prospective cohort of 1655 node-negative breast cancer patients with intensive clinical follow-up. Agreement in cause of death was evaluated using kappa statistics. The accuracy of OCR classification was evaluated against the Mount Sinai Hospital (MSH) study oncologist's interpretation of intensely followed, cohort-collected data as the reference standard. The two sources showed a high level of agreement (kappa statistic [kappa] = 0.88; 95% confidence interval [CI]: 0.86, 0.90) in vital status and cause of death. Among those cases where both sources reported a death, the OCR had a sensitivity of 95% (95% CI: 90.5, 98.8) and a specificity of 88% (95% CI: 79.6, 92.4). The OCR is a valuable tool for epidemiologic studies of breast cancer to acquire adequate and easily attainable cause-of-death information.

Publication types

  • Comparative Study
  • Multicenter Study

MeSH terms

  • Breast Neoplasms / mortality
  • Cause of Death*
  • Female
  • Humans
  • Neoplasms / mortality*
  • Ontario / epidemiology
  • Prospective Studies
  • Registries / statistics & numerical data*
  • Reproducibility of Results
  • Sensitivity and Specificity