Pancreatic cancer mortality and misclassification--bayesian analysis.

BACKGROUND Pancreatic cancer is a fatal cancer with a 5-year survival of only about 4% for all tumors. Mortality is a familiar projection to address the burden of cancers, but according to the Iranian death registry, about 20% of death statistics are still recorded in misclassified categories. The aim of this study was to estimate pancreatic cancer mortality for Iranian population, using a bayesian approach in order to revise this misclassification. METHODS National Death Statistics reported by the Ministry of Health from 1999 to 2004, stratified by age group, sex and cause of death, were the basis for this analysis. Pancreas cancer [ICD-10; 25] were expressed as the annual mortality rates/100,000, overall, by sex and by age group (<50 and ≥50 years of age) and age standardized rate (ASR). The bayesian approach to correct and account for misclassification effects in Poisson count regression was employed with a beta prior to estimate the mortality rate by age and sex group. RESULTS According to the bayesian analysis, there were between 20 to 30 percent underreported mortality records in deaths due to pancreatic cancer and the rate decreased slightly during the years of the study. CONCLUSION Our findings suggest a substantial undercount of pancreatic cancer mortality in the Iranian population. Therefore policy makers who determine research and treatment priorities should note these underreported data for death rates.