Reliability and validity of uterine cancer death certificates in the municipality of Belém, Pará, Brazil

Abstract

Belém, Pará State, Brazil, presents high mortality rates for uterine cervical cancer, thus justifying an analysis of the reliability and validity of data on this underlying cause of death. Death certificates for Belém residents who died in 1998-1999 from neoplasms of the uterine cervix, uterine body, or unspecified uterine site, or with mention of such a neoplasm on any line in the death certificate, were selected, amounting to 188 death certificates (DCs). All DCs were submitted to new coding, and reliability analysis was performed by simple agreement and Cohen's kappa. The underlying cause of death, established after review of medical records and/or histopathological findings, was considered the gold standard for analysis of criteria validity, based on the positive predictive value. We observed a simple agreement of 94.0% and kappa of 0.87, suggesting high reliability of the official system's coding of uterine cancer as the underlying cause of death. In the validity analysis, 120 of the 127 deaths originally considered as caused by cancer of the uterine cervix and 3 of the 4 coded as cancer of the uterine body were confirmed. An 11.2% increase in uterine cervical tumors and a reduction of 62.5% in unspecified uterine tumors were observed.