Validation of the verbal autopsy questionnaire for adult deaths in Iran

Background: Verbal Autopsy Questionnaire (VA) is an important tool to estimate the cause of death among those populations lacking an appropriate death registration system. In this study, the validity and reliability of verbal autopsy were assessed. Methods: The Persian version of the questionnaire was prepared using the translation and back- translation method. In the first and second phases of the study, 213 and 198 families of deceased persons accepted an invitation to complete the questionnaire. A physician determined the cause of death. These causes were compared with the registered cause of death on the death certificate. Sensitivity, specificity, positive predictive value (PPV), as well as the kappa statistic (between the first verbal autopsy questioning and death registry) were calculated to determine the validity of the questionnaire. Kappa statistic was also used to determine the reliability between the first and second questioning. Results: The sensitivity of the questionnaire varied from 75% among deaths due to diabetes to 100% Due to breast cancer. The specificity of the questionnaire for all causes of death was higher than 97%. PPV varied from 62.5% to 100% for all causes of death. The kappa statistic between causes of death derived from death certificate, and the first VA questioning for all causes of death was above 0.7 (p<0.001), and it was above 0.78 for the first and second verbal autopsy questioning (p<0.001). Conclusion: Although the Verbal Autopsy Questionnaire does not fully identify all causes of death, it can be a useful tool for diagnosing causes of death for those deceased persons who have no death certificate.